TY - CONF A1 - Resch-Genger, Ute A1 - Würth, Christian A1 - Pauli, Jutta A1 - Weigert, Florian T1 - Quantitative optical-spectroscopic characterization of luminescent nanomaterials - Photoluminescence Quantum Yields N2 - Accurate and quantitative photoluminescence measurements are mandatory for the comparison of different emitter classes and the rational design of the next generation of molecular and nanoscale reporters as well as for most applications relying on their luminescence features in the life and material sciences and nanobiophotonics. In the following, procedures for the determination of the spectroscopic key parameter photoluminescence quantum yield, i.e., the number of emitted per absorbed photons, in the UV/vis/NIR/SWIR are presented including pitfalls and achievable uncertainties and material-specific effects related to certain emitter classes are addressed. Special emphasis is dedicated to luminescent nanocrystals. T2 - International Workshop on "Emerging Nanomaterials for Displays and SSL" CY - Dresden, Germany DA - 11.11.2021 KW - Nano KW - Nanomaterial KW - Nanocrystal KW - Semiconductor quantum dot KW - Lanthanide KW - Photoluminescence KW - Quantum yield KW - Photophysics KW - Lifetime KW - Surface chemistry KW - Brightness KW - NIR KW - SWIR KW - Method KW - Uncertainty KW - Rreference material PY - 2021 AN - OPUS4-53783 LA - deu AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Reliable Photoluminescence Quantum Yields – New Reference Materials and Interlaboratory Comparisons N2 - The rational design and choice of molecular and nanoscale reporters, the comparison of different emitter classes, and photophysical and mechanistic studies require quantitative photoluminescence measurements and the reliable determination of the key performance parameter photoluminescence quantum yield (QY), i.e., the number of emitted per absorbed photons. This is of special importance for all photoluminescence applications in the life and material sciences in the UV/vis/NIR/SWIR. To improve the reliability and comparability of photoluminescence and QY measurements across laboratories, pitfalls, achievable uncertainties, and material-specific effects related to certain emitter classes must be explored. Also, suitable protocols and reference materials are needed which have been validated in interlaboratory comparisons for different wavelength regions and transparent and scattering luminophores.[1] Based on absolute and relative photoluminescence measurements of functional dyes and luminescent nanomaterials, reliable methods for determining QY of transparent and scattering luminophores, nonlinear emitters, and solid luminescent nanomaterials have been developed.[1-4] Thereby, material- and method-related uncertainties of relative and absolute QY measurements and achievable uncertainties could be quantified for linear and nonlinear UV/vis/NIR/SWIR emitters and lately for also luminescent and scattering materials and solid phoshors. In this context, we present the development and certification of a first set of UV/vis/NIR quantum yield standards with a complete uncertainty budget,[5] which present simple tools for a better comparability of QY measurements. In addition, a first interlaboratory comparison of absolute QY measurements of solid and scattering LED converter materials with integrating sphere spectroscopy has been performed.[5] The outcome of this study is presented, thereby addressing common pitfalls and measurement uncertainties and providing recommendations for the performance of reliable QY measurements of linear and non-linear emitters in transparent, scattering, and solid samples. T2 - Anakon 2025 CY - Leipzig, Germany DA - 10.03.2025 KW - Quality assurance KW - Reference material KW - Method KW - Fluorescence KW - Quantum yield KW - Absolute KW - Integrating sphere spectroscopy KW - Interlaboratory comparison KW - Dye KW - Film KW - Nano KW - Particle KW - Scattering KW - Uncertainty KW - LED converter PY - 2025 AN - OPUS4-62792 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Wang, Z. A1 - Wegner, Karl David A1 - Stiegler, L. M. S. A1 - Zhou, X. A1 - Rezvani, A. A1 - Odungat, A. S. A1 - Zubiri, B. A. A1 - Wu, M. A1 - Spiecker, E. A1 - Walter, J. A1 - Resch-Genger, Ute A1 - Segets, D. T1 - Optimizing the Shelling Process of InP/ZnS Quantum Dots Using a Single-Source Shell Precursor: Implications for Lighting and Display Applications N2 - InP/ZnS core/shell quantum dots (QDs), recognized as highly promising heavy-metal-free emitters, are increasingly being utilized in lighting and display applications. Their synthesis in a tubular flow reactor enables production in a highly efficient, scalable, and reproducible manner, particularly when combined with a single-source shell precursor, such as zinc diethyldithiocarbamate (Zn(S2CNEt2)2). However, the photoluminescence quantum yield (PLQY) of QDs synthesized with this route remains significantly lower compared with those synthesized in batch reactors involving multiple steps for the shell growth. Our study identifies the formation of absorbing, yet nonemissive ZnS nanoparticles during the ZnS shell formation process as a main contributing factor to this discrepancy. By varying the shelling conditions, especially the shelling reaction temperature and InP core concentration, we investigated the formation of pure ZnS nanoparticles and their impact on the optical properties, particularly PLQY, of the resultant InP/ZnS QDs through ultraviolet−visible (UV−vis) absorption, steady-state and time-resolved photoluminescence (PL) spectroscopy, scanning transmission electron microscopy (STEM), and analytical ultracentrifugation (AUC) measurements. Our results suggest that process conditions, such as lower shelling temperatures or reduced InP core concentrations (resulting in a lower external surface area), encourage homogeneous nucleation of ZnS. This reduces the availability of shell precursors necessary for effective passivation of the InP core surfaces, ultimately resulting in lower PLQYs. These findings explain the origin of persistently underperforming PLQY of InP/ZnS QDs synthesized from this synthesis route and suggest further optimization strategies to improve their emission for lighting and display applications. KW - Nano KW - Particle KW - Synthesis KW - InP KW - Shell KW - Fluorescence KW - Quantum yield KW - ZnS KW - Semiconductor KW - Quantum dot KW - Flow reactor KW - Method KW - AUC KW - Size KW - Automation KW - Sensor PY - 2024 DO - https://doi.org/10.1021/acsanm.4c05265 SN - 2574-0970 VL - 7 IS - 20 SP - 24262 EP - 24273 PB - ACS Publications AN - OPUS4-61518 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Amouroux, B. A1 - Würth, Christian A1 - Roux, C. A1 - Eftekhari, A. A1 - Sliwa, M. A1 - Bouchet, A. A1 - Micheau, J.-C. A1 - Resch-Genger, Ute A1 - Coudret, C. T1 - Time-Resolved Rate Equation Analysis Disclose Kinetics Controlling Luminescence of Nanometer Tm-Upconverting Nanoparticles N2 - Upconversion luminescence of lanthanide-based upconversion nanoparticles (UCNPs) is a nonlinear step-wise process in which the consecutive absorption of multiple, low-energy photons results in the subsequent emission of a high-energy photon. The primary upconversion mechanism is energy transfer upconversion (ETU) from a sensitizer (Yb3+) to an activator (Tm3+). It requires the absorption of several excitation lowenergy photons by Yb3+, followed by the sequential energy transfer to Tm3+ions. Excited states relax to their ground states either radiatively by emitting a high-energy photon or non-radiatively by multiphonon relaxation through the crystalline host matrix. The time-resolved rise and decay luminescence curves of a set of five ultrasmall have been recorded under varying power near-infrared μs pulses. Six wavelengths have been used to monitor the evolution of the main Yb and Tm excited states. We use an average rate equations model to decipher the relationships between the compositional constraints and size of these ultrasmall UCNPs and the luminescence kinetic parameters. Several rate constants of ETU and other depopulation processes involving the multiple states of the Tm3+ energy scaffold have been retrieved from the simultaneous fit of the recorded curves. Their values have been interpreted by considering bulk and surface quenching, radiative and multi-phonon relaxations, and ion-to-ion hopping. Energy transfer between Yb3+ and Tm3+ is mainly occurring within neighbor atoms. The importance of mismatches on multiphonon relaxations, ETUs, and back-transfers has also been highlighted. For these numerical modeling, it appears that changing the composition and synthesis conditions with the aim to improve a single-specific parameter could remain a major challenge as this modification would automatically impact other properties with immediate consequences on UCNP dynamics. KW - Nano KW - Particle KW - Synthesis KW - Shell KW - Fluorescence KW - Lifetime KW - Decay kinetics KW - Method KW - Modelling KW - Quality assurance KW - Energy transfer KW - Upconversation PY - 2024 DO - https://doi.org/10.1021/acs.jpcc.4c04969 VL - 128 IS - 44 SP - 18836 EP - 18848 PB - ACS Publications AN - OPUS4-61645 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Labrador-Paez, Lucia, L. A1 - Kankare, J. A1 - Hyppanen, I. A1 - Soukka, T. A1 - Andresen, Elina A1 - Resch-Genger, Ute A1 - Widengren, J A1 - Liu, H. T1 - Frequency-Domain Method for Characterization of Upconversion Luminescence Kinetics N2 - The frequency-domain (FD) method provides an alternative to the commonly used time-domain (TD) approach in characterizing the luminescence kinetics of luminophores, with its own strengths, e.g., the capability to decouple multiple lifetime components with higher reliability and accuracy. While extensively explored for characterizing luminophores with down-shifted emission, this method has not been investigated for studying nonlinear luminescent materials such as lanthanide-doped upconversion nanoparticles (UCNPs), featuring more complicated kinetics. In this work, employing a simplified rate-equation model representing a standard two-photon energy-transfer upconversion process, we thoroughly analyzed the response of the luminescence of UCNPs in the FD method. We found that the FD method can potentially obtain from a single experiment the effective decay rates of three critical energy states of the sensitizer/activator ions involved in the upconversion process. The validity of the FD method is demonstrated by experimental data, agreeing reasonably well with the results obtained by TD methods. KW - Quality assurance KW - Luminescence KW - Method KW - Quantitative spectroscopy KW - Nano KW - Particle KW - Lifetime KW - Method development PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-597435 DO - https://doi.org/10.1021/acs.jpclett.3c00269 SP - 3436 EP - 3444 AN - OPUS4-59743 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Introduction to Fluorescence Spectroscopy N2 - A brief introduction to fluorescence spectroscopy will be provided, ranging from typically measured fluorescence quantities over instrument-specific contributions to measured fluorescence signals to selected applications. In this context, an overview of the photoluminescence properties of molecular and nanoscale luminescence reporters will be given including a brief insight into their photophysics and fluorescence standards designed by division Biophotonics for the calibration and instrument performance validation of fluorescence measuring devices will be presented. T2 - Analytical Academy CY - Berlin, Germany DA - 13.01.2020 KW - Linearity KW - Fluorescence KW - Dye KW - Quality assurance KW - Nnano particle KW - Method KW - Measurement uncertainty KW - Quantification PY - 2020 AN - OPUS4-51618 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Scholtz, Lena A1 - Tavernaro, Isabella A1 - Eckert, J. G. A1 - Lutowski, Marc A1 - Geißler, Daniel A1 - Hertwig, Andreas A1 - Hidde, Gundula A1 - Bigall, N. C. A1 - Resch-Genger, Ute T1 - Influence of nanoparticle encapsulation and encoding on the surface chemistry of polymer carrier beads N2 - Surface-functionalized polymer beads encoded with molecular luminophores and nanocrystalline emitters such as semiconductor nanocrystals, often referred to as quantum dots (QDs), or magnetic nanoparticles are broadly used in the life sciences as reporters and carrier beads. Many of these applications require a profound knowledge of the chemical nature and total number of their surface functional groups (FGs), that control bead charge, colloidal stability, hydrophobicity, and the interaction with the environment and biological systems. For bioanalytical applications, also the number of groups accessible for the subsequent functionalization with, e.g., biomolecules or targeting ligands is relevant. In this study, we explore the influence of QD encoding on the amount of carboxylic acid (COOH) surface FGs of 2 μm polystyrene microparticles (PSMPs). This is done for frequently employed oleic acid and oleylamine stabilized, luminescent core/shell CdSe QDs and two commonly used encoding procedures. This included QD addition during bead formation by a thermally induced polymerization reaction and a post synthetic swelling procedure. The accessible number of COOH groups on the surface of QD-encoded and pristine beads was quantified by two colorimetric assays, utilizing differently sized reporters and electrostatic and covalent interactions. The results were compared to the total number of FGs obtained by a conductometric titration and Fourier transform infrared spectroscopy (FTIR). In addition, a comparison of the impact of QD and dye encoding on the bead surface chemistry was performed. Our results demonstrate the influence of QD encoding and the QD-encoding strategy on the number of surface FG that is ascribed to an interaction of the QDs with the carboxylic acid groups on the bead surface. These findings are of considerable relevance for applications of nanoparticle-encoded beads and safe-by-design concepts for nanomaterials. KW - Optical spectroscopy KW - Particle KW - Optical assay KW - IR spectroscopy KW - Fluorescence KW - Quantum yield KW - Quality assurance KW - Nano KW - Synthesis KW - Surface chemistry KW - Quantification KW - Method KW - Conductometry PY - 2023 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-581502 DO - https://doi.org/10.1038/s41598-023-38518-7 SN - 2045-2322 VL - 13 IS - 1 SP - 1 EP - 15 PB - Springer Nature CY - London AN - OPUS4-58150 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Fiedler, Saskia A1 - Frenzel, Florian A1 - Würth, Christian A1 - Tavernaro, Isabella A1 - Grüne, M. A1 - Schweizer, S. A1 - Engel, A. A1 - Resch-Genger, Ute T1 - Interlaboratory Comparison on Absolute Photoluminescence Quantum Yield Measurements of Solid Light Converting Phosphors with Three Commercial Integrating Sphere Setups N2 - Scattering luminescent materials dispersed in liquid and solid matrices and luminescent powders are increasingly relevant for fundamental research and industry. Examples are luminescent nano- and microparticles and phosphors of different compositions in various matrices or incorporated into ceramics with applications in energy conversion, solid-state lighting, medical diagnostics, and security barcoding. The key parameter to characterize the performance of these materials is the photoluminescence/fluorescence quantum yield (Φf), i.e., the number of emitted photons per number of absorbed photons. To identify and quantify the sources of uncertainty of absolute measurements of Φf of scattering samples, the first interlaboratory comparison (ILC) of three laboratories from academia and industry was performed by following identical measurement protocols. Thereby, two types ofcommercial stand-alone integrating sphere setups with different illumination and detection geometries were utilized for measuring the Φf of transparent and scattering dye solutions and solid phosphors, namely, YAG:Ce optoceramics of varying surface roughness, used as converter materials for blue light emitting diodes. Special emphasis was dedicated to the influence of the measurement geometry, the optical properties of the blank utilized to determine the number of photons of the incident excitation light absorbed by the sample, and the sample-specific surface roughness. While the Φf values of the liquid samples matched between instruments, Φf measurements of the optoceramics with different blanks revealed substantial differences. The ILC results underline the importance of the measurement geometry, sample position, and blank for reliable Φf data of scattering the YAG:Ce optoceramics, with the blank’s optical properties accounting for uncertainties exceeding 20%. KW - Nano KW - Fluorescence KW - Reference material KW - Luminescence KW - Quantitative spectroscopy KW - Particle KW - Quantum yield KW - Quality assurance KW - Phosphor KW - Converter material KW - Lifetime KW - Interlaboratory comparison KW - Method KW - Uncertainty PY - 2024 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-600945 DO - https://doi.org/10.1021/acs.analchem.4c00372 SN - 0003-2700 SP - 6730 EP - 6737 PB - ACS Publications AN - OPUS4-60094 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Tavernaro, Isabella A1 - Sander, P. C. A1 - Andresen, Elina A1 - Schedler, U. A1 - Resch-Genger, Ute T1 - Expanding the Toolbox of Simple, Cost-Efficient, and Automatable Methods for Quantifying Surface Functional Groups on Nanoparticles� Potentiometric Titration N2 - Measuring surface functional groups (FGs) on nanomaterials (NMs) is essential for designing dispersible and stable NMs with tailored and predictable functionality. FG screening and quantification also plays a critical role for subsequent processing steps, NM long-term stability, quality control of NM production, and risk assessment studies and enables the implementation of sustainable and safe(r)-by-design concepts. This calls for simple and cost-efficient methods for broadly utilized FGs that can be ideally automated to speed up FG screening, monitoring, and quantification. To expand our NM surface analysis toolbox, focusing on simple methods and broadly available, cost-efficient instrumentation, we explored a NM-adapted pH titration method with potentiometric and optical readout for measuring the total number of (de)protonable FGs on representatively chosen commercial and custom-made aminated silica nanoparticles (SiO2 NPs). The accuracy and robustness of our stepwise optimized workflows was assessed by several operators in two laboratories and method validation was done by cross-comparison with two analytical methods relying on different signal generation principles. This included traceable, chemo-selective quantitative nuclear magnetic resonance spectroscopy (qNMR) and thermogravimetric analysis (TGA), providing the amounts of amino silanes released by particle dissolution and the total mass of the surface coatings. A comparison of the potentiometric titration results with the reporter-specific amounts of surface amino FGs determined with the previously automated fluorescamine (Fluram) assay highlights the importance of determining both quantities for surface-functionalized NMs. In the future, combined NM surface analysis with optical assays and pH titration will simplify quality control of NM production processes and stability studies and can yield large data sets for NM grouping that facilitates further developments in regulation and standardization. KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Characterization KW - Advanced material KW - Surface KW - Standardization KW - Reference material KW - Functional group KW - Quantification KW - Coating KW - Automation KW - Potentiometry KW - Method KW - Validation KW - Optical assay KW - Fluram KW - Fluorescamine KW - qNMR KW - Comparison KW - ILC PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-642371 DO - https://doi.org/10.1021/acsmeasuresciau.5c00062 SN - 2694-250X SP - 1 EP - 13 PB - American Chemical Society CY - Washington, DC AN - OPUS4-64237 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Ahiboz, D. A1 - Andresen, Elina A1 - Manley, P. A1 - Resch-Genger, Ute A1 - Würth, Christian A1 - Becker, C. T1 - Metasurface-Enhanced Photon Upconversion upon 1550 nm Excitation N2 - Photon upconversion upon 1550 nm excitation is of high relevance for applications in the third biological excitation window, for photovoltaics beyond current limitations, and enables appealing options in the field of glass Fiber telecommunications. Trivalent doped erbium ions (Er3+) are the material of choice for 1550 nm excited upconversion, however, they suffer from a low absorption cross-section and a low brightness. Therefore, the ability of Silicon metasurfaces to provide greatly enhanced electrical near-fields is employed to enable efficient photon upconversion even at low external Illumination conditions. Hexagonally shaped β-NaYF4:Er3+ nanoparticles are placed on large-area silicon metasurfaces designed to convert near-infrared (1550 nm) to visible light. More than 2400-fold enhanced photon upconversion luminescence is achieved by using this metasurface instead of a planar substrate. With the aid of optical simulations based on the finite-element method, this result is attributed to the coupling of the excitation source with metasurface resonances at appropriate incident angles. Analysis of the excitation power density dependence of upconversion luminescence and red-to-green-emission ratios enables the estimation of nanoscale near-field enhancement on the metasurface. The findings permit the significant reduction of required external excitation intensities for photon upconversion of 1550 nm light, opening perspectives in biophotonics, telecommunication, and photovoltaics. KW - Nano KW - Nanomaterial KW - Upconversion nanoparticle KW - Lanthanide KW - Photoluminescence KW - Quantum yield KW - Photophysics KW - Lifetime KW - Sensor KW - Excitation power density KW - Single particle KW - Brightness KW - NIR KW - Mechanism KW - Single enhancement KW - SWIR KW - Method PY - 2021 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-537193 DO - https://doi.org/10.1002/adom.202101285. SN - 2195-1071 VL - 9 IS - 24 SP - 2101285 PB - Wiley-VCH-GmbH AN - OPUS4-53719 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Molecular and nanoscale emitters photophysics , photoluminescence quantum yields, and surface chemistry N2 - Inorganic nanocrystals such as spectrally shifting lanthanide-based nanoparticles (LnNCs) like NaYF4: Yb, Er and semiconductor quantum dots, organic and inorganic particles stained with sensor molecules, and organic dyes showing aggregation-induced emission are meanwhile broadly applied in the life and material sciences. The identification of optimum particle architectures and molecular structures for photonic applications requires quantitative spectroscopic studies and methods to control and analyse particle surface chemistry. In the following, photoluminescence studies of different emitter classes are presented, thereby addressing the measurement of particle brightness and photoluminescence quantum yields in different spectral windows parameters required for an in-depth mechanistic understanding. In addition, examples for the quantification of surface functional groups on nanomaterials with optical spectroscopy are given. T2 - GdCH Kolloquium CY - Düsseldorf, Germany DA - 11.11.2025 KW - Dye KW - Fluorescence KW - Quantum yield KW - Lifetime KW - Sensor materials KW - Temperature KW - Cr(III) complex KW - Nano KW - Particle KW - Silica KW - Polymer KW - Metrology KW - Quality assurance KW - Reference material KW - Surface chemistry KW - Size KW - Shape KW - Particle number concentration KW - Method KW - Optical assay KW - qNMR KW - Validation KW - Potentiometry KW - XPS PY - 2025 AN - OPUS4-64728 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Wegner, Karl David A1 - Kalot, G. A1 - Busser, B. A1 - Pliquett, J. A1 - Köster, U. A1 - Koll, J. C. A1 - Denat, F. A1 - Bodio, E. A1 - Goze, C. A1 - Sacey, L. T1 - NIR aza-BODIPY: a new vector for boron neutron capture therapy (BNCT) N2 - Boron neutron capture therapy (BNCT) relies on the activation of 10B by thermal neutrons, which results in small highly energetic particle emission inducing cancer cells damage. However, in order to overcome the limits of the currently used BNCT agents, it is necessary to design new systems, which can specifically accumulate and deliver a sufficient amount of 10B in tumors. In this study, we designed a 10B-BSH-containing aza-BODIPY (aza-SWIR-BSH). It enabled the efficient vectorization of clinically used 10B-BSH to the tumor, resulting in higher therapeutic activity than the 10B-BSH alone. T2 - EMIM 2021 CY - Göttingen, Germany DA - 24.08.2021 KW - Flourescence KW - Optical probe KW - Dye KW - Photophysics KW - Quantum yield KW - Mechanism KW - NIR KW - SWIR KW - Imaging KW - Method KW - Quality assurance KW - BODIPY KW - Boron Neutron Capture Therapy (BNCT) KW - Medicine KW - Life sciences PY - 2021 AN - OPUS4-53731 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Rezvani, A. A1 - Wang, Z. A1 - Wegner, Karl David A1 - Soltanmoradi, H. A1 - Kichigin, A. A1 - Zhou, X. A1 - Gantenberg, T. A1 - Schram, J. A1 - Zubiri, B. A. A1 - Spiecker, E. A1 - Walter, J. A1 - Resch-Genger, Ute A1 - Segets, D. T1 - Separation of Indium Phosphide/Zinc Sulfide Core−Shell Quantum Dots from Shelling Byproducts through Multistep Agglomeration N2 - Semiconductor quantum dots (QDs) possess unique electronic and optical properties, making them promising candidates for applications in lightemitting diodes, solar cells, bioimaging, and photocatalysis. Precise control over their size, shape, and chemical and electronic structure is crucial to ensure the desired functional properties and optimize device performance. However, challenges in QD synthesis and post-synthesis modification persist, especially in large-scale production. This study addresses the classification of QDs synthesized in a tubular flow reactor consisting of a mixture of the desired InP/ZnS core−shell QDs and QDs made from the shell material, i.e., here ZnS QDs formed as a byproduct during the formation step of the ZnS shell. The homogeneous nucleation of ZnS nanoparticles from the shelling material introduces a heterogeneity in size and composition and affects the optical properties of the resulting QDs. To address this issue, we developed a size-selective agglomeration (SSA) technique by incrementally introducing ethanol as a poor solvent and classified the synthesized QDs into 13 distinct fractions. These 13 fractions are sorted into three distinct groups: (i) larger InP/ZnS QDs, (ii) a combination of smaller InP/ZnS QDs and larger ZnS QDs, and (iii) predominant ZnS QDs with some very tiny InP/ZnS QDs. The comprehensive characterization of the fractions was conducted using UV−visible absorption spectroscopy, photoluminescence spectroscopy, high-resolution scanning transmission electron microscopy, energy-dispersive X-ray spectroscopy, total reflection X-ray fluorescence, and analytical ultracentrifugation. We could demonstrate that our method effectively separated unwanted ZnS QDs from the target InP/ZnS QDs. In addition, the fractions enriched in smaller InP/ZnS QDs exhibited a higher photoluminescence quantum yield compared to the fractions with larger QDs. This demonstrates the efficacy of SSA in finetuning the composition of QD mixtures produced on a larger scale to improve their functional properties. This approach provides fundamental understanding toward the development of a scalable two-dimensional classification process for such ultrasmall nanoparticles by particle size and composition. KW - Quality assurance KW - Reference material KW - Nano KW - Particle KW - Quantum dot KW - Synthesis KW - Flow reactor KW - InP KW - Shell KW - ZnS KW - Surface chemistry KW - Method KW - Fluorescence KW - Quantum yield KW - TEM PY - 2025 DO - https://doi.org/10.1021/acsnano.4c18530 SN - 1936-086X VL - 19 IS - 20 SP - 19080 EP - 19094 PB - ACS Publications AN - OPUS4-63215 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kage, Daniel A1 - Hoffmann, Katrin A1 - Borcherding, H. A1 - Schedler, U. A1 - Resch-Genger, Ute T1 - Lifetime encoding in flow cytometry for bead‑based sensing of biomolecular interaction N2 - To demonstrate the potential of time-resolved flow cytometry (FCM) for bioanalysis, clinical diagnostics, and optically encoded bead-based assays, we performed a proof-of-principle study to detect biomolecular interactions utilizing fluorescence lifetime (LT)-encoded micron-sized polymer beads bearing target-specific bioligands and a recently developed prototype lifetime flow cytometer (LT-FCM setup). This instrument is equipped with a single excitation light source and different fluorescence detectors, one operated in the photon-counting mode for time-resolved measurements of fluorescence decays and three detectors for conventional intensity measurements in different spectral windows. First, discrimination of bead-bound biomolecules was demonstrated in the time domain exemplarily for two targets, Streptavidin (SAv) and the tumor marker human chorionic gonadotropin (HCG). In a second step, the determination of biomolecule concentration levels was addressed representatively for the inflammation-related biomarker tumor necrosis factor (TNF-α) utilizing fluorescence intensity measurements in a second channel of the LT-FCM instrument. Our results underline the applicability of LT-FCM in the time domain for measurements of biomolecular interactions in suspension assays. In the future, the combination of spectral and LT encoding and multiplexing and the expansion of the time scale from the lower nanosecond range to the longer nanosecond and the microsecond region is expected to provide many distinguishable codes. This enables an increasing degree of multiplexing which could be attractive for high throughput screening applications. KW - Fluorescence KW - Sensor KW - Assay KW - Protein KW - Multiplexing KW - Flow cytometry KW - Barcoding KW - Lifetime KW - Dye KW - Bead KW - Bead-based assay KW - Method KW - Quantification PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-516007 DO - https://doi.org/10.1038/s41598-020-76150-x VL - 10 IS - 1 SP - 19477 PB - Nature AN - OPUS4-51600 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Daly, H.C A1 - Matikonda, S.S A1 - Steffens, H.C A1 - Rühle, Bastian A1 - Resch-Genger, Ute A1 - Ivanic, J. A1 - Schermann, M.J T1 - Daly_Photochem Photobiol 2021_Ketone Incorporation Extends the Emission Properties of the Xanthene Scaffold N2 - Imaging in the shortwave-infrared region (SWIR, λ = 1000–2500 nm) has the potential to enable deep tissue imaging with high resolution. Critical to the development of these Methods is the identification of low molecular weight, biologically compatible fluorescent probes that emit beyond 1000 nm. Exchanging the bridging oxygen atom on the xanthene scaffold (C10’ position) with electron withdrawing groups has been shown to lead to significant redshifts in absorbance and emission. Guided by quantum chemistry computational modeling studies, we investigated the installation of a Ketone bridge at the C10’ position. This simple modification extends the absorbance maxima to 860 nm and the emission beyond 1000 nm, albeit with reduced photon output. Overall, These studies demonstrate that broadly applied xanthene dyes can be extended into the SWIR range. KW - Flourescence KW - Optical probe KW - Dye KW - Photophysics KW - Quantum yield KW - Mechanism KW - NIR KW - SWIR KW - Imaging KW - Reliability KW - Method KW - Quality assurance PY - 2021 DO - https://doi.org/10.1111/php.13544 SN - 1751-1097 VL - 98 IS - 2 SP - 325 EP - 333 PB - Wiley Online Library AN - OPUS4-54080 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Pauli, Jutta A1 - Würth, Christian A1 - Güttler, Arne A1 - Resch-Genger, Ute T1 - Reliable Determination of the Signal-Relevant Spectroscopic Key Characteristics of Luminescent Reporters and Optical Probes for Imaging in the vis/NIR/SWIR N2 - Introduction. Comparing different emitter classes and rationally designing the next generation of molecular and nanoscale probes for bioimaging applications require accurate and quantitative methods for the measurement of the key parameter photoluminescence quantum yield f.1 f equals the number of emitted per number of absorbed photons. This is particularly relevant for increasingly used fluorescence imaging in the short wave-infrared region (SWIR) ≥ 900 nm providing deeper penetration depths, a better image resolution, and an improved signal-to-noise or tumor-to-background ratio.2, 3 However, spectroscopic measurements in the SWIR are more challenging and require specific calibrations and standards. T2 - EMIM 2021 CY - Göttingen, Germany DA - 24.08.2021 KW - Fluorescence KW - Optical probe KW - Dye KW - Photophysics KW - Quantum yield KW - Mechanism KW - NIR KW - SWIR KW - Imaging KW - Reference material KW - Reliability KW - Nano KW - Particle KW - Method KW - Quality assurance PY - 2021 AN - OPUS4-53233 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Measuring the Upconversion Luminescence of Ensemble and Single Particle Lanthanide-Based Upconversion Nanocrystals N2 - Lanthanide-based upconversion nanoparticles (UCNPs) like hexagonal 𝛽-NaYF4 UCNPs doped with Yb3+ and Er3+, which efficiently convert 976 nm light to ultraviolet, visible, and near infrared photons, offer new strategies for luminescence-based sensing, barcoding, and Imaging. Their upconversion (UC) luminescence (UCL) features like UCL intensity, quantum yield, relative spectral distribution / UCL luminescence color, and luminescence decay kinetics are, however, strongly influenced by particle size, dopant ion concentration, particle architecture, surface chemistry including presence and thickness of surface passivation and shielding shells, microenvironment/presence of quenchers with high energy vibrations, and excitation power density (P). We present here a comprehensive study of the influence of excitation power density on the UCL features of different types of UCNPs, focusing on Yb3+ and Er3+ co-doped NaYF4 core-only and core-shell nanostructures with different sizes and doping ion concentration, which underlines the importance of P-dependent optimum dopant concentrations for UCNP performance and the potential of P-tuning of UCL. T2 - Materials Challenges in Alternative & Renewable Energy 2021 (MCARE 2021) CY - Online meeting DA - 19.07.2021 KW - Fluorescence KW - Lifetime KW - Method KW - Stability KW - Coating KW - Surface chemistry KW - Lanthanide KW - Upconversion KW - Nano KW - Particle KW - Single particle spectroscopy KW - Quantum yield KW - Microscopy KW - Photophysics PY - 2021 AN - OPUS4-53111 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Absolute spectroscopic characterization of the optical properties of semiconductor and upconversion nanocrystals in the vis and IR N2 - Nanocrystalline fluorophores like semiconductor quantum dots and rods and recently also lanthanide-based upconversion phosphors with emission in the visible (vis), near-infrared (NIR), and IR (infrared) region are increasingly being used in bioimaging studies and fluorescence assays as well as in photovoltaics and solid state lighting. The assessment and comparison of material performance as well as the development of rational design strategies for improved systems require spectroscopic tools, which enable the determination of the signal-relevant optical properties like photoluminescence quantum yields and brightness values. In the case of nonlinear fluorescence as shown by upconversion materials, such measurements must be also performed as function of excitation power density. In this work, we report on methods for the absolute determination of the photoluminescence quantum yield and brightness of fluorescent particles in dispersion and as powders based on integrating sphere spectroscopy and underline the importance of such measurements for the understanding of the photophysics of such nanocrystals. T2 - International Conference on Fundamental Processes in Semiconductor Nanocrystals (FQDots16) CY - Berlin, Germany DA - 05.09.2016 KW - Fluorescence KW - Nanoparticle KW - Semiconductor quantum dot KW - Upconversion nanocrystal KW - NIR KW - Integrating sphere spectroscopy KW - Fluorescence quantum yield KW - Method PY - 2016 AN - OPUS4-38695 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Typical Measurements in Optical Spectroscopy – Absorption Spectroscopy or Photometry N2 - The basics of absorption spectroscopy (termed also photometry) will be presented with focus on transparent solutions of different molecular and nanocrystalline absorbers and the ultraviolet (UV), visible (vis), and near-infrared (NIR) spectral region. Thereby, also typical sources of uncertainty will be addressed. Subsequently, several examples for typical applications of absorption measurements in the life and material sciences will be briefly shown ranging from aggregation studies and dye labeling densities of biomolecules (dye-to-biomolecule ratios) over optical assays for thiol and protein quantification to the optical determination of the size of semiconductor nanocrystals using size curves. T2 - pHD Seminar CY - Online meeting DA - 03.11.2020 KW - Quantification KW - Absorption KW - Dye KW - Nano particle KW - Method KW - Measurement uncertainty KW - Linearity PY - 2020 AN - OPUS4-51621 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Introduction to Fluorescence Spectroscopy N2 - A brief introduction to fluorescence spectroscopy will be provided, ranging from typically measured fluorescence quantities over instrument-specific contributions to measured fluorescence signals to selected applications. In this context, an overview of the photoluminescence properties of molecular and nanoscale luminescence reporters will be given including a brief insight into their photophysics and fluorescence standards designed by division Biophotonics for the calibration and instrument performance validation of fluorescence measuring devices will be presented. T2 - Analytical Academy BAM CY - Online meeting DA - 17.11.2020 KW - Fluorescence KW - Quality assurance KW - Quantification KW - Linearity KW - Measurement uncertainty KW - Method KW - Nano particle KW - Dye PY - 2020 AN - OPUS4-51619 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Suitable geometries for the measurement of photoluminescence quantum yields of luminescent and scattering samples – The DIN TNS project N2 - The characterization of the optical properties of photoluminescent systems, that scatter, like dispersions of nanoparticles with sizes exceeding about 25 nm or solid nanophosphors is of increasing importance for many applications in the life and material sciences. Examples present nanoscale optical reporters and dye-doped microparticles for bioimaging, fluorescence assays or DNA sequencing as well as nanocrystalline emitters like semiconductor quantum dots and rods or lanthanide-based nanophosphors embedded into solid matrices for solid state lighting, display technologies, or barcoding/security applications. The assessment and comparison of material performance as well as the development of rational design strategies for improved systems require spectroscopic tools, which enable the determination of the signal-relevant optical properties like photoluminescence quantum yields and brightness values. This encouraged us to built up an integrating sphere setup enabling absolute measurements of photoluminescence spectra and quantum yields of transparent and scattering photoluminescent dispersions and solid samples in different measurement geometries, i.e., direct and indirect illumination and the combination of both geometries and perform first measurements with selected emitters. Here, the design of this setup is presented and first recommendations concerning suitable measurement geometries are given. T2 - DKE-Sitzung CY - Frankfurt am Main, Germany DA - 31.08.2016 KW - Nanoparticle KW - Integrating sphere KW - Fluorescence KW - Quantum yield KW - Method KW - Standardization KW - Calibration KW - Reference material PY - 2016 AN - OPUS4-38643 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Resch-Genger, Ute ED - Mousavi, M. ED - Thomasson, B. ED - Li, M. ED - Kraft, Marco ED - Würth, Christian ED - Andersson-Engels, S. T1 - Beam-profile-compensated quantum yield measurements of upconverting nanoparticles N2 - The quantum yield is a critically important parameter in the development of lanthanide-based upconverting nanoparticles (UCNPs) for use as novel contrast agents in biological imaging and optical reporters in assays. The present work focuses on the influence of the beam Profile in measuring the quantum yield (f) of nonscattering dispersions of nonlinear upconverting probes, by establishing a relation between f and excitation light power density from a rate equation analysis. A resulting 60% correction in the measured f due to the beam profile utilized for excitation underlines the significance of the beam profile in such measurements, and its impact when comparing results from different Setups and groups across the world. KW - Fluorescence KW - Lanthanide KW - Upconversion KW - Brithtness KW - Quantification KW - Nanoparticle KW - Absolute fluoreometry KW - NIR KW - IR KW - Quantum yield KW - Integrating sphere spectroscopy KW - Method PY - 2017 DO - https://doi.org/10.1039/c7cp03785f SN - 1463-9076 SN - 1463-9084 VL - 19 IS - 33 SP - 22016 EP - 22022 PB - Royal Society of Chemistry AN - OPUS4-42583 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Huang, K. A1 - Liu, H. A1 - Kraft, Marco A1 - Shikha, S. A1 - Zheng, X. A1 - Agren, H. A1 - Würth, Christian A1 - Resch-Genger, Ute A1 - Zhang, Y. T1 - A protected excitation-energy reservoir for efficient upconversion luminescence N2 - Lanthanide-doped upconversion nanoparticles (UCNPs) are of great interest for biomedical applications. Currently, the applicability of UCNP bionanotechnology is hampered by the generally low luminescence intensity of UCNPs and inefficient energy Transfer from UCNPs to surface-bound chromophores used e.g. for photodynamic therapy or analyte sensing. In this work, we address the low-Efficiency issue by developing versatile core-Shell nanostructures, where high-concentration sensitizers and activators are confined in the core and Shell Region of representative hexagonal NaYF2:Yb,Er UCNPs. After Doping concentration optimization, the sensitizer-rich core is able to harvest/accumulate more excitation energy and generate almost one order of Magnitude higher luminescence intesity than conventional homogeneously doped nanostructures. At the same time, the activator Ions located in the Shell enable a ~6 times more efficient resonant energy Transfer from UCNPs to surface-bound acceptor dye molecules due to the short distance between donor-acceptor pairs. Our work provides new insights into the rational design of UCNPs and will greatly encrease the General applicability of upconversion nanotechnologies. KW - Fluorescence KW - Lanthanide KW - Upconversion KW - Brightness KW - Quantification KW - Nanoparticle KW - Absolute fluorometry KW - NIR KW - IR KW - Quantum yield KW - Integrating sphere spectroscopy KW - Method KW - Energy transfer KW - Shell KW - Particle architecture PY - 2017 DO - https://doi.org/10.1039/c7nr06900f SN - 2040-3372 SN - 2040-3364 VL - 10 IS - 1 SP - 250 EP - 259 PB - The Royal Society of Chemistry AN - OPUS4-43893 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Absolute Determination of Photoluminescence Quantum Yields of Scattering LED Converter Materials – How to Get it Right N2 - Optical measurements of scattering luminescent materials dispersed in liquid and solid matrices and luminescent powders play an important role in fundamental research and industry. Typical examples are luminescent nano- and microparticles and phosphors of different composition in different matrices or incorporated into ceramics with applications in energy conversion, solid-state lighting, medical diagnostics, and security barcoding. The key parameter for the performance of these materials is the photoluminescence quantum yield QY, i.e., the number of emitted photons per number of absorbed photons. QY of transparent luminophore solutions can be determined relatively to a fluorescence quantum yield standard of known QY. Such standards are meanwhile available as certified reference materials.[1] The determination of QY of scattering liquid and solid samples like dispersions of luminescent nanoparticles, solid phosphors, and optoceramics requires, however, absolute measurements with an integrating sphere setup. Although the importance of reliable absolute QY measurements has been recognized, no interlaboratory comparisons (ILCs) on measurement uncertainties and the identification of typical sources of uncertainty have been yet reported. Also, no scattering reference materials with known QY are available. We present here the results of a first ILC of 3 laboratories from academia and industry performed to identify and quantify sources of uncertainty of absolute QY measurements of scattering samples. Thereby, two types of commercial stand-alone integrating sphere setups with different illumination and detection geometries were utilized for measuring QY of transparent and scattering dye solutions and solid phosphors. As representative and industrially relevant solid and scattering samples, YAG:Ce optoceramics of varying surface roughness were chosen, applied, e.g., as converter materials for blue light emitting diodes. Special emphasis was dedicated to the influence of the measurement geometry, the optical properties of the blank, utilized to determine the number of photons of the incident excitation light absorbed by the sample, and the sample-specific surface roughness. While matching QY values could be obtained for transparent dye solutions and scattering dispersions, here using a blank with scattering properties closely matching those of the sample, QY measurements of optoceramic samples with different blanks revealed substantial differences, with the blank's optical properties accounting for measurement uncertainties of more than 20 %. Based upon the ILC results, we recommend non-absorbing blank materials with a high reflectivity (>95 %) such as a 2 mm-thick PTFE target placed on the sample holder which reveals a near-Lambertian light scattering behavior, yielding a homogeneous light distribution within the integrating sphere. T2 - e-MRS 2024 CY - Strasbourg, France DA - 27.05.2024 KW - Luminescence KW - Quantitative spectroscopy KW - Nano KW - Particle KW - Quantum yield KW - Lifetime KW - Quality assurance KW - Phosphor KW - Converter marterial KW - Fluorescence KW - Interlaboratory KW - Comparison KW - Method KW - Uncertainty KW - Reference material PY - 2024 AN - OPUS4-60490 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kunc, F. A1 - Nirmalananthan-Budau, Nithiya A1 - Rühle, Bastian A1 - Sung, Y. A1 - Johnston, L.J. A1 - Resch-Genger, Ute T1 - Interlaboratory Comparison on the Quantification of Total and Accessible Amine Groups on Silica Nanoparticles with qNMR and Optical Assays N2 - Risk assessment of nanomaterials requires not only standardized toxicity studies but also validated methods for nanomaterial surface characterization with known uncertainties. In this context, a first bilateral interlaboratory comparison on Surface group quantification of nanomaterials is presented that assesses different reporter-free and labeling methods for the quantification of the total and accessible number of amine functionalities on commercially available silica nanoparticles that are widely used in the life sciences. The overall goal of this comparison is the identification of optimum methods as well as achievable measurement uncertainties and the comparability of the results across laboratories. We also examined the robustness and ease of implementation of the applied analytical methods and discussed method-inherent limitations. In summary, this comparison presents a first step toward the eventually required standardization of methods for surface group quantification. KW - Nano KW - Nanomaterial KW - Surface KW - Method KW - QNMR KW - Quantification KW - Comparison KW - Quality assurance KW - Optical probe KW - Sensor KW - Interlabority comparison KW - Standardization KW - Optical assay KW - Functional group analysis KW - Silica KW - Particle KW - Safety KW - Environment PY - 2021 DO - https://doi.org/10.1021/acs.analchem.1c02162 SN - 1520-6882 VL - 93 IS - 46 SP - 15271 EP - 15278 PB - ASC Publications AN - OPUS4-53818 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Andresen, Elina A1 - Resch-Genger, Ute A1 - Michaelis, Matthias A1 - Prinz, Carsten A1 - Würth, Christian T1 - Time-resolved luminescence spectroscopy for monitoring the stability and dissolution behaviour of upconverting nanocrystals with different surface coatings† N2 - We demonstrate the potential of time-resolved luminescence spectroscopy for the straightforward assessment and in situ monitoring of the stability of upconversion nanocrystals (UCNPs). Therefore, we prepared hexagonal NaYF4:Yb3+,Er3+ UCNPs with various coatings with a focus on phosphonate ligands of different valency, using different ligand exchange procedures, and studied their dissolution behaviour in phosphate-buffered saline (PBS) dispersions at 20 °C and 37 °C with various analytical methods. The amount of the released UCNPs constituting fluoride ions was quantified by potentiometry using a Fluoride ion-sensitive electrode and particle disintegration was confirmed by transmission electron microscopy studies of the differently aged UCNPs. In parallel, the luminescence features of the UCNPs were measured with special emphasis on the lifetime of the sensitizer emission to demonstrate its suitability as Screening parameter for UCNP stability and changes in particle composition. The excellent correlation between the changes in luminescence lifetime and fluoride concentration highlights the potential of our luminescence lifetime method for UCNP stability screening and thereby indirect monitoring of the release of potentially hazardous fluoride ions during uptake and dissolution in biological systems. Additionally, the developed in situ optical method was used to distinguish the dissolution dynamics of differently sized and differently coated UCNPs. KW - Fluorescence KW - Lifetime KW - Method KW - Quantification KW - Stability KW - Coating KW - Surface chemistry KW - Lanthanide KW - Fluoride KW - Electrochemistry KW - ICP-OES KW - Upconversion KW - Nano KW - Particle KW - Aging KW - Quality assurance KW - TEM PY - 2020 DO - https://doi.org/10.1039/d0nr02931a VL - 12 IS - 23 SP - 12589 EP - 12601 PB - Royal Society od Chemistry AN - OPUS4-52088 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Influence of Surface Chemistry and Size on the Stability of β-NaYF4:Yb,Er Nanocrystals in Various Environments N2 - The use of inorganic lanthanide-doped upconversion nanoparticles (UCNP) in bioimaging and cellular studies requires biocompatible particles. One possible cause of UCNP toxicity is the release of potentially harmful fluoride and lanthanide ions as revealed by dilution studies in aqueous environments, particularly under high dilution conditions. To address this issue, suitable surface coatings preventing such effects in combination with fast screening methods suited for online monitoring and in situ analyses are desired. Here we present systematic studies of differently sized β-NaYF4:Yb,Er UCNP stabilized with different surface coatings and hydrophilic ligands varying in binding strength to the particle surface in various aqueous environments at different temperatures and UCNP concentrations. The concentration of the fluoride and lanthanide ions released upon particle dissolution was quantified electrochemically with a fluoride ion-sensitive electrode and inductively coupled plasma optical emission spectrometry (ICP-OES) and monitored fluorometrically, thereby exploiting the sensitivity of the upconversion luminescence to changes in size and surface chemistry. Moreover, changes in surface chemistry were determined with X-Ray photoelectron spectroscopy (XPS). Based upon our results, we could derive optimum screening parameters for UCNP stability studies and determine conditions and coating procedures and ligands for enhancing UCNP stability in aqueous environments. T2 - UPCON2021 CY - Online meeting DA - 06.04.2021 KW - Fluorescence KW - Lifetime KW - Method KW - Quantification KW - Stability KW - Coating KW - Surface chemistry KW - Lanthanide KW - Fluoride KW - Electrochemistry KW - ICP-OES KW - Upconversion KW - Nano KW - Particle KW - Aging KW - Quality assurance KW - Mass spectrometry KW - XPS PY - 2021 AN - OPUS4-52411 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Kossatz, Philipp A1 - Mezhov, Alexander A1 - Andresen, Elina A1 - Prinz, Carsten A1 - Schmidt, Wolfram A1 - Resch-Genger, Ute T1 - Assessing the Applicability of Lanthanide-Based Upconverting Nanoparticles for Optically Monitoring Cement Hydration and Tagging Building Materials N2 - Chemically stable, lanthanide-based photon upconversion micro- and nanoparticles (UCNPs) with their characteristic multicolor emission bands in the ultraviolet (UV), visible (vis), near-infrared (NIR), and short-wave infrared (SWIR) arepromising optical reporters and barcoding tags. To assess the applicability of UCNPs for the monitoring of early stage cement hydration processes and as authentication tags for cementitious materials, we screened the evolution of the luminescence of Selfmade core-only NaYF4:Yb,Er UCNPs and commercial μm-sized Y2O2S:Yb,Er particles during the first stages of cement hydration, which largely determines the future properties of the hardened material. Parameters explored from the UCNP side included particle size, morphology, surface chemistry or coating, luminescence properties, and concentration in different cement mixtures. From the cement side, the influence of the mineral composition of the cement matrix was representatively examined for ordinary Portland cement (OPC) and its constituents tricalcium aluminate (C3A), tricalcium silicate (C3S), and gypsum at different water to cement ratios. Based on reflection and luminescence measurements, enabling online monitoring, which were complemented by XRD and isothermal heat-flow calorimetric measurements to determine whether the incorporation of these particles could impair cement hydration processes, well suited lanthanide particle reporters could be identified as well as application conditions. In addition, thereby the reporter influence on cement hydration kinetics could be minimized while still preserving a high level of information content. The best performance for the luminescence probing of changes during early stage cement hydration processes was observed for 25 nm-sized oleate (OA)-coated UCNPs added in a concentration of 0.1 wt %. Higher UCNP amounts of 1.0 wt % delayed cement hydration processes size- and surface coatingspecifically in the first 24 h. Subsequent luminescence stability screening studies performed over a period of about one year support the applicability of UCNPs as optical authentication tags for construction materials. KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Quantum yield KW - NIR KW - Mechanism KW - Characterization KW - XRD KW - Calorimetry KW - Advanced material KW - Cement KW - Monitoring KW - Surface KW - Size KW - Lifetime KW - Barcode KW - Lanthanide KW - Upconversion KW - Encoding KW - Method PY - 2025 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-638318 DO - https://doi.org/10.1021/acsomega.5c02236 SN - 2470-1343 VL - 10 IS - 29 SP - 31587 EP - 31599 PB - ACS Publications CY - Washington, DC AN - OPUS4-63831 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - The emp project smurfnano – Standardizing the quantification of surface functionalities, ligands, and coatings on nanomaterials N2 - For industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, opto-electronics, and information storage, meanwhile engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely fabricated. NP function, interaction with biological species, and environmental fate are largely determined by surface functionalities. Reliable, reproducible, and standardized surface characterization methods are therefore vital for quality control of NPs, and mandatory to meet increasing concerns regarding their safety. Also, industry, international standardization organizations, regulatory agencies, and policymakers need validated and standardized measurement methods and reference materials. These needs are addressed by the recently started European metrology project SMURFnano involving 12 partners from different National Metrology Institutes, designated institutes, and research institutes, two university groups as well as one large company and one SME producing NPs. This project as well as first results derived from the development of test and reference materials with a well characterized surface chemistry and ongoing interlaboratory comparisons will be presented. T2 - LNE Workshop CY - Paris, France DA - 04.11.2025 KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Characterization KW - Advanced material KW - Surface KW - Standardization KW - Reference material KW - Functional group KW - Quantification KW - Coating KW - Automation KW - Potentiometry KW - Method KW - Validation KW - Optical assay KW - Fluram KW - qNMR KW - Comparison KW - ILC PY - 2025 AN - OPUS4-64725 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Characterization and quantification of functional groups and coatings on nanoobjects an overview N2 - Characterization of Nanoparticles – Questions to Ask, Functional Nanoparticles (NPs) – Organic, Inorganic, and Hybrid Nanoparticles Nanomaterial Characterization Standardization – Addressing Remaining Gaps Surface FGs Particle Surface Chemistry - Why is it Important? Particle Surface Chemistry - A Key Driver for Performance, Applications, and Safety Aspects Method Development for Quantifying FGs and Ligands on Particle Surfaces FG Quantification – Method Choice & Criteria Relevant for Data Interpretation Quantifying the Amount of Total and Accessible FGs on Aminated Silica Nanoparticles (SiO2-NH2) Comparing the Total and Accessible –NH2 Content on Aminated Silica NPs of Different Size Characterization of Nanoparticles Standardization Standardized Measurements of Surface FGs on Nanoparticles EMP Project SMURFnano EMP Project SMURFnano Work Packages & Goals Certified Reference Materials from BAM T2 - e-MRS 2024 (Spring Meeting of the European Materials Research Society, Altech Symposium) CY - Strasbourg, France DA - 27.05.2024 KW - Luminescence KW - Nano KW - Particle KW - Quantum yield KW - Quality assurance KW - Interlaboratory comparison KW - Method KW - Uncertainty KW - Reference material KW - Surface analysis KW - Optical assay KW - NMR KW - Silica KW - Ligand PY - 2024 AN - OPUS4-60495 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute A1 - Tavernaro, Isabella A1 - Abram, Sarah-Luise A1 - Homann, Christian A1 - Scholtz, Lena A1 - Radnik, Jörg T1 - Validated and standardized measurements and quantification of surface functionalities on nanoparticles N2 - Engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely fabricated for industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, opto-electronics, and information storage which improve the quality of life and European prosperity. Nanoparticle function, interaction with biological species, and environmental fate are largely determined by surface functionalities. Reliable, reproducible, and standardized surface characterization methods are therefore vital for quality control of NPs, and mandatory to meet increasing concerns regarding their safety. Also, industry, regulatory agencies, and policymakers need validated traceable measurement methods and reference materials. Industry, e.g., must comply with various regulations, including the chemicals´ regulation REACH (2006/1907) and cosmetic products regulation (2009/1223), depending on the use. Therefore, standardization organizations such as the European Committee for Standardization (CEN), the International Organization for Standardization (ISO), and the International Electrotechnical Commission (IEC) as well as industrial stakeholders, European Medicine Agency (EMA), and the nanosafety community responsible for guidelines for nanomaterial (NM) regulation like the Organisation for Economic Co-operation and Development (OECD) have expressed needs for standardized methodologies to measure NP surface chemical properties. Despite these needs, methodologies for determining NP surface properties, including the amount, chemical composition, and homogeneity of surface functionalities and coatings are largely non-standardized. Specifically, validated quantitative procedures for the measurement of thickness and composition of nanoparticle coatings and other surface functionalities are needed. Suitable methods for determining surface functionalities on ligand-stabilized core and core/shell NPs include advanced techniques such as traceable quantitative nuclear magnetic resonance (qNMR) as well as X-ray electron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS), and simpler optical and electrochemical methods. The latter less costly methods are often used by SMEs, e.g., for quality control. To validate methods, establish measurement uncertainties, test reference materials, and produce reference data, international interlaboratory comparisons (ILC) on NP surface functionalization measurements are required. These needs have been addressed by us in two interlaboratory comparisons, that will be presented. In addition, the European metrology project SMURFnano will be briefly presented involving 12 partners from different National Metrology Institutes, designated institutes, and research institutes, two university groups as well as one large company and one SME producing NPs. T2 - NanoCarbon Annual Conference 2025 CY - Würzburg, Germany DA - 18.03.2025 KW - Nano KW - Particle KW - Silica KW - Quality assurance KW - Reference material KW - Surface chemistry KW - Size KW - Shape KW - Particle number concentration KW - Method KW - Optical assay KW - QNMR KW - Validation KW - Potentiometry KW - XPS PY - 2025 AN - OPUS4-62790 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Quantifying the total and accessible amount of surface functionalities and ligands on nano-materials: Overview and recommended methods N2 - Engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely fabricated for industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, opto-electronics, and information storage. NP function, interaction with biological species, and environmental fate are largely determined by surface functionalities. This calls for reliable, reproducible, and standardized surface characterization methods, which are vital for quality control of NPs, and mandatory to meet increasing concerns regarding their safety. Validated and standardized workflows for surface analysis are also increasingly requested by industry, international standardization organizations, regulatory agencies, and policymakers. To establish comparable measurements of surface functionalities across different labs and ease instrument performance validation, reference test materials and reference materials of known surface chemistry as well as reference data are needed. In the following, different methods for determining surface functionalities on ligand-stabilized core and core/shell NPs include advanced techniques are presented and discussed regarding method-inherent advantages and limitations. Special emphasis is dedicated to traceable quantitative nuclear magnetic resonance (qNMR), X-ray electron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS), and simpler optical and electrochemical methods. T2 - LNE Workshop CY - Paris, France DA - 04.11.2025 KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Characterization KW - Advanced material KW - Surface KW - Standardization KW - Reference material KW - Functional group KW - Quantification KW - Coating KW - Automation KW - Potentiometry KW - Method KW - Validation KW - Optical assay KW - Fluram KW - Fluorescamine KW - qNMR KW - Comparison KW - ILC PY - 2025 AN - OPUS4-64726 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Standardized Measurements of Surface - Functionalities on Nanoparticles N2 - Engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely fabricated for industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, optoelectronics, and information storage. NP function, interaction with biological species, and environmental fate are largely determined by surface functionalities. Reliable, reproducible, and standardized surface characterization methods are therefore vital for quality control of NPs, and mandatory to meet increasing concerns regarding their safety. Also, industry, international standardization organizations, regulatory agencies, and policymakers need validated and standardized measurement methods and reference materials. However, methodologies for determining NP surface properties, including the amount, chemical composition, and homogeneity of surface functionalities and coatings are largely non-standardized. Suitable methods for determining surface functionalities on ligand-stabilized core and core/shell NPs include advanced techniques such as traceable quantitative nuclear magnetic resonance (qNMR) as well as X-ray electron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS), and simpler optical and electrochemical methods. The latter less costly methods are often used by SMEs, e.g., for quality control. To validate methods, establish measurement uncertainties, test reference materials, and produce reference data, international interlaboratory comparisons (ILC) on NP surface functionalization measurements are required and well characterized test and reference nanomaterials providing benchmark values.[1] These needs are addressed by the recently started European metrology project SMURFnano involving 12 partners from different National Metrology Institutes, designated institutes, and research institutes, two university groups as well as one large company and one SME producing NPs. This project as well as first results derived from the development of test and reference materials with a well characterized surface chemistry and ongoing interlaboratory comparisons will be presented. T2 - eMRS CY - Strasbourg, France DA - 27.05.2025 KW - Quality assurance KW - Fluorescence KW - Nano KW - Particle KW - Synthesis KW - Silica KW - Upconversion nanoparticles KW - Optical assay KW - qNMR KW - Surface analysis KW - Ligand KW - Quantification KW - Functional group KW - XPS KW - ToF-SIMS KW - Polymer particle KW - Surface modification KW - Potentiometry KW - Metrology KW - Method KW - Validation KW - ILC PY - 2025 AN - OPUS4-63339 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Standardized Measurements of Surface Functionalities on Nanoparticles - F. Synthesis and characterization of functional nanocomposite materials N2 - Engineered nanoparticles (NPs) with various chemical compositions and surface functionalities are routinely and commonly fabricated for industrial applications such as medical diagnostics, drug delivery, sensing, catalysis, energy conversion and storage, opto-electronics, and information storage. NP function, their interaction with biological species, and also their environmental fate are largely determined by the surface functionalities of the particles. Reliable, reproducible, and standardized surface characterization methods are therefore vital for quality control of NPs, determination of their applicability, and mandatory to meet increasing concerns regarding their safety. In addition, industry as well as international standardization organizations, regulatory agencies, and policymakers need validated and standardized measurement methods and reference materials. However, methodologies for determining NP surface properties, including the amount, chemical composition, and homogeneity of surface functionalities and coatings are largely non-standardized up until now. Suitable methods for determining surface functionalities on ligand-stabilized core and core/shell NPs include advanced techniques such as traceable quantitative nuclear magnetic resonance (qNMR), as well as X-ray electron spectroscopy (XPS) and time of flight secondary ion mass spectrometry (ToF-SIMS), and simpler optical and electrochemical methods. The latter, typically less costly methods are often used by SMEs, e.g., for quality control. To validate methods, establish measurement uncertainties, test reference materials, and produce reference data, international interlaboratory comparisons (ILC) on NP surface functionalization measurements are required to provide well characterized test and reference nanomaterials including benchmark values.[1] These needs are addressed by the current European metrology project SMURFnano, involving 12 partners from different National Metrology Institutes, designated and research institutes, two university groups as well as one large company and one SME producing NPs. This project, as well as first results derived from the development of test and reference materials with a well characterized surface chemistry, and ongoing interlaboratory comparisons, will be presented. T2 - Shift 2025 CY - La Laguna, Tenerife DA - 13.10.2025 KW - Nano KW - Particle KW - Silica KW - Iron oxide KW - Lanthanide KW - Metrology KW - Quality assurance KW - Reference material KW - Surface chemistry KW - Size KW - Shape KW - Particle number concentration KW - Method KW - Optical assay KW - qNMR KW - Validation KW - Potentiometry KW - XPS KW - ILC KW - Standardization PY - 2025 AN - OPUS4-64370 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Gharaati, S. A1 - Wang, Cui A1 - Förster, C. A1 - Weigert, Florian A1 - Resch-Genger, Ute A1 - Heinze, K. T1 - Triplet–Triplet Annihilation Upconversion in a MOF with AcceptorFilled Channels N2 - In summary, we report a highly modular solid TTA-UC system comprising of a crystalline, thermally stable PCN222(Pd) MOF with CA-coated MOF channels and with a DPA annihilator embedded in a solution-like environment in the MOF channels. This solid material displays blue upconverted delayed emission with a luminescence lifetime of 373 us, a threshold value of 329 mW*cm-2 and a triplet–triplet energy transfer efficiency of 82%. This optical application adds another facet to the versatile chemistry of PCN-222 MOFs. The design concept is also applicable to other TTA-UC pairs and enables tuning of the UCL color, for example, by replacing DPA with other dyes as exemplarily shown for 2,5,8,11-tetra-tert-butyl-perylene, that yields UCL at 450 nm. Current work aims to reduce the oxygen sensitivity and to increase the retention of the trapped annihilators in organic environments, for example, by tuning the chain length of the carboxylic acid and by coating the MOF surface. In addition, the TTA-UC efficiency will be further enhanced by reducing the reabsorption of the UC emission caused by Pd(TCPP) and by optimizing the sensitizer/annihilator interface. KW - Porphyrin KW - Method KW - MOF KW - Fluorescence KW - Dye KW - Sensor KW - Oxygen sensitive KW - Single molecule KW - DPA KW - Lifetime KW - Upconverstion KW - Quantum yield KW - Triplet-triplet annihilation KW - Sensitization KW - Energy transfer KW - NMR PY - 2019 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-500580 DO - https://doi.org/10.1002/chem.201904945 VL - 26 IS - 5 SP - 1003 EP - 1007 PB - Wiley-VCH Verlag CY - Weinheim AN - OPUS4-50058 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Luminescent nanocrystals – Photophysics and applications for lifetime multiplexing N2 - Bioanalytical, diagnostic, and security applications require the fast and sensitive determination of a steadily increasing number of analytes or events in parallel in a broad variety of detection formats.[1,2] Ideal candidates for spectral encoding and multiplexing schemes are luminescent nanocrystals like semiconductor quantum dots (QDs), particularly Cd-containing II/VI QDs with their narrow and symmetric emission bands. With the availability of relatively simple and inexpensive instrumentation for time-resolved fluorescence measurements, similar strategies utilizing the compound-specific parameter fluorescence lifetime or fluorescence decay kinetics become increasingly attractive.[3-5] The potential of different types of QDs like II/VI, III/V and Cd-free ternary QDs such as AgInS (AIS) QDs for lifetime-based encoding and multiplexing has been, however, barely utilized, although the lifetimes of these nanocrystals cover a time windows which is barely accessible with other fluorophores. Here we present a brief insight into the photophysics of AIS QDs and show the potential of dye- and QD-encoded beads for lifetime-based encoding and detection schemes in conjunction with flow cytometry and fluorescence lifetime imaging microscopy T2 - Nanax 2019 CY - Hamburg, Germany DA - 16.09.2019 KW - Nano KW - Microparticle KW - Bead KW - Encoding KW - Lifetime KW - Multiplexing KW - Flow cytometry KW - Bead-based assay KW - Fluorescence KW - Dye KW - LT-FCM KW - Time-resolved flow cytometry KW - Method PY - 2019 AN - OPUS4-49039 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Saleh, Maysoon I. A1 - Rühle, Bastian A1 - Wang, Shu A1 - Radnik, Jörg A1 - You, Yi A1 - Resch-Genger, Ute T1 - Assessing the protective effects of different surface coatings on NaYF4:YB3+, Er3+, upconverting nanoparticles in buffer and DMEM N2 - We studied the dissolution behavior of β NaYF4:Yb(20%), Er(2%) UCNP of two different sizes in biologically relevant media i.e., water (neutral pH), phosphate buffered saline (PBS), and Dulbecco’s modified Eagle medium (DMEM) at different temperatures and particle concentrations. Special emphasis was dedicated to assess the influence of different surface functionalizations, particularly the potential of mesoporous and microporous silica shells of different thicknesses for UCNP stabilization and protection. Dissolution was quantified electrochemically using a fluoride ion selective electrode (ISE) and by inductively coupled plasma optical emission spectrometry (ICP OES). In addition, dissolution was monitored fluorometrically. These experiments revealed that a thick microporous silica shell drastically decreased dissolution. Our results also underline the critical influence of the chemical composition of the aqueous environment on UCNP dissolution. In DMEM, we observed the formation of a layer of adsorbed molecules on the UCNP surface that protected the UCNP from dissolution and enhanced their fluorescence. Examination of this layer by X ray photoelectron spectroscopy (XPS) and mass spectrometry (MS) suggested that mainly phenylalanine, lysine, and glucose are adsorbed from DMEM. These findings should be considered in the future for cellular toxicity studies with UCNP and other nanoparticles and the design of new biocompatible surface coatings. KW - Fluorescence KW - Lifetime KW - Method KW - Quantification KW - Stability KW - Coating KW - Surface chemistry KW - Lanthanide KW - Fluoride KW - Electrochemistry KW - ICP-OES KW - Upconversion KW - Nano KW - Particle KW - Aging KW - Quality assurance KW - Mass spectrometry KW - XPS PY - 2020 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-515984 DO - https://doi.org/10.1038/s41598-020-76116-z SN - 2045-2322 VL - 10 IS - 1 SP - 19318-1 EP - 19318-11 PB - Springer Nature CY - London AN - OPUS4-51598 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - CONF A1 - Resch-Genger, Ute T1 - Perspective of BAM on Advanced Materials N2 - A brief perspective of BAM on advanced materials is presented including examples for nanomaterials and other systems presenting advanced materials with special emphasis on characterization methods used in different division of BAM for the determination of functional or safety parameters of such materials. In this respect, also ongoing activities of the capacity building project nanoplatform of BAM aiming at the development of nanometer-sized reference materials are briefly summarized. T2 - BfR Workshop zu Advanced Materials CY - Online meeting DA - 04.11.2020 KW - Quality assurance KW - Risk assessment KW - Safety KW - Core/shell particle KW - Characterization KW - Measurement uncertainty KW - Method KW - Nano particle PY - 2020 AN - OPUS4-51620 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Resch-Genger, Ute A1 - Meermann, Björn A1 - Koch, Matthias A1 - Weller, Michael G. T1 - Editorial: Analytical methods and applications in materials and life sciences N2 - Current trends in materials and life sciences are flanked by the need to push detection limits to single molecules or single cells, enable the characterization of increasingly complex matrices or sophisticated nanostructures, speed up the time of analysis, reduce instrument complexity and costs, and improve the reliability of data. This requires suitable analytical tools such as spectroscopic, separation and imaging techniques, mass spectrometry, and hyphenated techniques as well as sensors and their adaptation to application-specific challenges in the environmental, food, consumer product, health sector, nanotechnology, and bioanalysis. Increasing concerns about health threatening known or emerging pollutants in drinking water, consumer products, and food and about the safety of nanomaterials led to a new awareness of the importance of analytical sciences. Another important driver in this direction is the increasing demand by legislation, particularly in view of the 17 sustainable development goals by the United Nations addressing clean energy, industry, and innovation, sustainable cities, clean water, and responsible consumption and production. In this respect, also the development of analytical methods that enable the characterization of material flows in production processes and support recycling concepts of precious raw materials becomes more and more relevant. In the future, this will provide the basis for greener production in the chemical industry utilizing recycled or sustainable starting materials. This makes analytical chemistry an essential player in terms of the circular economy helping to increase the sustainability of production processes. In the life sciences sector, products based on proteins, such as therapeutic and diagnostic antibodies, increase in importance. These increasingly biotechnologically produced functional biomolecules pose a high level of complexity of matrix and structural features that can be met only by highly advanced methods for separation, characterization, and detection. In addition, metrological traceability and target definition are still significant challenges for the future, particularly in the life sciences. However, innovative reference materials as required for the health and food sector and the characterization of advanced materials can only be developed when suitable analytical protocols are available. The so-called reproducibility crisis in sciences underlines the importance of improved measures of quality control for all kinds of measurements and material characterization. This calls for thorough method validation concepts, suitable reference materials, and regular interlaboratory comparisons of measurements as well as better training of scientists in analytical sciences. The important contribution of analytical sciences to these developments is highlighted by a broad collection of research papers, trend articles, and critical reviews from these different application fields. Special emphasis is dedicated to often-overlooked quality assurance and reference materials. T2 - 150 years BAM: Science with impact CY - Berlin, Germany DA - 01.01.2021 KW - Analysis KW - Life sciences KW - Analytical sciences KW - Quality assurance KW - Reference material KW - Fluorescence KW - Nanoparticle KW - Sensor KW - Material sciences KW - Pollutant KW - Environment KW - Method KW - Limit of detection KW - 150th anniversary KW - ABC KW - BAM KW - Collection KW - Editorial KW - Special issue KW - Bundesanstalt für Materialforschung und -prüfung KW - Jahrestag PY - 2022 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-550720 DO - https://doi.org/10.1007/s00216-022-04082-8 SN - 1618-2642 SN - 1618-2650 VL - 414 IS - Topical collection: Analytical methods and applications in the materials and life sciences SP - 4267 EP - 4268 PB - Springer CY - Berlin AN - OPUS4-55072 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -