TY - JOUR A1 - Büchner, T. A1 - Drescher, D. A1 - Merk, V. A1 - Traub, Heike A1 - Guttmann, P. A1 - Werner, St. A1 - Jakubowski, Norbert A1 - Schneider, G. A1 - Kneipp, J. T1 - Biomolecular environment, quantification, and intracellular interaction of multifunctional magnetic SERS nanoprobes JF - Analyst N2 - Multifunctional composite nanoprobes consisting of iron oxide nanoparticles linked to silver and gold nanoparticles, Ag–Magnetite and Au–Magnetite, respectively, were introduced by endocytic uptake into cultured fibroblast cells. The cells containing the non-toxic nanoprobes were shown to be displaceable in an external magnetic field and can be manipulated in microfluidic channels. The distribution of the composite nanostructures that are contained in the endosomal system is discussed on the basis of surfaceenhanced Raman scattering (SERS) mapping, quantitative laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) micromapping, and cryo soft X-ray tomography (cryo soft-XRT). Cryo soft-XRT of intact, vitrified cells reveals that the composite nanoprobes form intra-endosomal aggregates. The nanoprobes provide SERS signals from the biomolecular composition of their surface in the endosomal environment. The SERS data indicate the high stability of the nanoprobes and of their plasmonic properties in the harsh environment of endosomes and lysosomes. The spectra point at the molecular composition at the surface of the Ag–Magnetite and Au–Magnetite nanostructures that is very similar to that of other Composite structures, but different from the composition of pure silver and gold SERS nanoprobes used for intracellular investigations. As shown by the LA-ICP-MS data, the uptake efficiency of the magnetite composites is approximately two to three times higher than that of the pure gold and silver nanoparticles. KW - Nanoparticles KW - SERS KW - Cell KW - LA-ICP-MS KW - X-ray tomography PY - 2016 UR - https://nbn-resolving.org/urn:nbn:de:kobv:b43-371811 DO - https://doi.org/10.1039/c6an00890a SN - 0003-2654 VL - 141 IS - 17 SP - 5096 EP - 5106 PB - Royal Society of Chemistry CY - Cambridge, UK AN - OPUS4-37181 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Büchner, Tina A1 - Drescher, Daniela A1 - Traub, Heike A1 - Schrade, P. A1 - Bachmann, S. A1 - Jakubowski, Norbert A1 - Kneipp, Janina T1 - Relating surface-enhanced Raman scattering signals of cells to gold nanoparticle aggregation as determined by LA-ICP-MS micromapping JF - Analytical and bioanalytical chemistry N2 - The cellular response to nanoparticle exposure is essential in various contexts, especially in nanotoxicity and nanomedicine. Here, 14-nm gold nanoparticles in 3T3 fibroblast cells are investigated in a series of pulse-chase experiments with a 30-min incubation pulse and chase times ranging from 15 min to 48 h. The gold nanoparticles and their aggregates are quantified inside the cellular ultrastructure by laser ablation inductively coupled plasma mass spectrometry micromapping and evaluated regarding the surface-enhanced Raman scattering (SERS) signals. In this way, both information about their localization at the micrometre scale and their molecular nanoenvironment, respectively, is obtained and can be related. Thus, the nanoparticle pathway from endocytotic uptake, intracellular processing, to cell division can be followed. It is shown that the ability of the intracellular nanoparticles and their accumulations and aggregates to support high SERS signals is neither directly related to nanoparticle amount nor to high local nanoparticle densities. The SERS data indicate that aggregate geometry and interparticle distances in the cell must change in the course of endosomal maturation and play a critical role for a specific gold nanoparticle type in order to act as efficient SERS nanoprobe. This finding is supported by TEM images, showing only a minor portion of aggregates that present small interparticle spacing. The SERS spectra obtained after different chase times show a changing composition and/or structure of the biomolecule corona of the gold nanoparticles as a consequence of endosomal processing. KW - Gold nanoparticles KW - Surface-enhanced Raman scattering KW - LA-ICP-MS KW - Fibroblast KW - Cell KW - Particle aggregation KW - Endosome PY - 2014 DO - https://doi.org/10.1007/s00216-014-8069-0 SN - 1618-2642 SN - 1618-2650 VL - 406 IS - 27 SP - 7003 EP - 7014 PB - Springer CY - Berlin AN - OPUS4-31718 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Pisonero, J. A1 - Bouzas-Ramos, D. A1 - Traub, Heike A1 - Cappella, Brunero A1 - Alvarez-Llamas, C. A1 - Richter, Silke A1 - Mayo, J. C. A1 - Costa-Fernandez, J. M. A1 - Bordel, N. A1 - Jakubowski, Norbert T1 - Critical evaluation of fast and highly resolved elemental distribution in single cells using LA-ICP-SFMS JF - Journal of Analytical Atomic Spectrometry N2 - The analytical potential of a nanosecond laser ablation inductively coupled plasma mass spectrometer (ns-LA-ICP-SFMS) system, equipped with an ultra-fast wash-out ablation chamber, is critically investigated for fast and highly spatially resolved (∼μm) qualitative elemental distribution within single cells. Initially, a low surface roughness (< 10 nm) thin In–SnO2 layer (total coating thickness ∼200 nm) deposited on glass is employed to investigate the size, morphology and overlapping of laser-induced craters obtained at different laser repetition rates, making use of Atomic Force Microscopy (AFM). Conical craters with a surface diameter of about 2 µm and depths of about 100 nm were measured after a single laser shot. Furthermore, the influence of the sampling distance (i.e. distance between the sample surface and the inner sniffer of the ablation chamber) on the LA-ICP-MS ion signal wash-out time is evaluated. A significant decrease of the transient 120Sn+ ion signal is noticed after slight variations (±200 μm) around the optimum sampling position. Ultra-fast wash-outs (< 10 ms) are achieved reducing the aerosol mixing from consecutive laser shots even when operating the laser at high repetition rates (25 – 100 Hz). Fast and highly spatially resolved images of elemental distribution within mouse embryonic fibroblast cells (NIH/3T3 fibroblast cells) and human cervical carcinoma cells (HeLa cells), incubated with gold nanoparticles (Au NPs) and Cd-based quantum dots (QDs), respectively, are determined at the optimized operating conditions. Elemental distribution of Au and Cd in single cells is achieved using a high scanning speed (50 µm/s) and high repetition rate (100 Hz). The results obtained for the distribution of fluorescent Cd-based QDs within the HeLa cells are in good agreement with those obtained by confocal microscopy. The size, morphology and overlapping of laser-induced craters in the fixed cells are also investigated using AFM, observing conical craters with a surface diameter of about 2.5 µm and depths of about 800 nm after a single laser shot. KW - Laser ablation KW - ICP-MS KW - Nanoparticle KW - Atomic Force Microscopy KW - Cell PY - 2018 DO - https://doi.org/10.1039/c8ja00096d SP - 1 EP - 9 PB - Royal Society of Chemistry CY - Cambridge AN - OPUS4-45564 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Arakawa, Akihiro A1 - Jakubowski, Norbert A1 - Koellensperger, G. A1 - Theiner, S. A1 - Schweikert, A. A1 - Flemig, Sabine A1 - Iwahata, D. A1 - Traub, Heike A1 - Hirata, T. T1 - Quantitative Imaging of Silver Nanoparticles and Essential Elements in Thin Sections of Fibroblast Multicellular Spheroids by High Resolution Laser Ablation Inductively Coupled Plasma Time-of-Flight Mass Spectrometry JF - Analytical Chemistry N2 - We applied high resolution laser ablation inductively coupled plasma time-of-flight mass spectrometry (LA-ICP-TOF-MS) with cellular spatial resolution for bioimaging of nanoparticles uptaken by fibroblast multicellular spheroids (MCS). This was used to quantitatively investigate interactions of silver nanoparticles (Ag NPs) and the distributions of intrinsic minerals and biologically relevant elements within thin sections of a fibroblast MCS as a three-dimensional in vitro tissue model. We designed matrix-matched calibration standards for this purpose and printed them using a noncontact piezo-driven array spotter with a Ag NP suspension and multielement standards. The limits of detection for Ag, Mg, P, K, Mn, Fe, Co, Cu, and Zn were at the femtogram (fg) level, which is sufficient to investigate intrinsic minerals in thin MCS sections (20 μm thick). After incubation for 48 h, Ag NPs were enriched in the outer rim of the MCS but not detected in the core. The localization of Ag NPs was inhomogeneous in the outer rim, and they were colocalized with a single-cell-like structure visualized by Fe distribution (pixel size of elemental images: 5 × 0.5 μm). The quantitative value for the total mass of Ag NPs in a thin section by the present method agreed with that obtained by ICP-sector field (SF)-MS with a liquid mode after acid digestion. KW - Laser ablation KW - ICP-MS KW - Imaging KW - Nanoparticle KW - Cell KW - Spheroid PY - 2019 UR - https://pubs.acs.org/doi/10.1021/acs.analchem.9b02239 DO - https://doi.org/10.1021/acs.analchem.9b02239 SN - 0003-2700 VL - 91 IS - 15 SP - 10197 EP - 10203 PB - American Chemical Society, ACS Publications CY - Washington D.C. AN - OPUS4-48719 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Arakawa, Akihiro A1 - Jakubowski, Norbert A1 - Koellensperger, G. A1 - Theiner, S. A1 - Schweikert, A. A1 - Flemig, Sabine A1 - Iwahata, D. A1 - Traub, Heike A1 - Hirata, T. T1 - Imaging of Ag NP transport through collagen-rich microstructures in fibroblast multicellular spheroids by high-resolution laser ablation inductively coupled plasma time-of-flight mass spectrometry JF - Analyst N2 - We investigated the penetration of silver nanoparticles (Ag NPs) into a three-dimensional in vitro tissue analog using NPs with various sizes and surface coatings, and with different incubation times. A high-Resolution laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) time-of-flight (TOF) instrument was applied for imaging the distributions of elements in thin sample sections (20 μm thick). A fibroblast multicellular spheroid (MCS) was selected as the model system and cultured for more than 8 days to produce a natural barrier formed by the extracellular matrix containing collagen. The MCS was then exposed for up to 48 h to one of four types of Ag NPs (∅ 5 nm citrate coated, ∅ 20 nm citrate coated, ∅ 20 nm polyvinylpyrrolidone coated, and ∅ 50 nm citrate coated). Imaging showed that the penetration pathway was strongly related to steric networks formed by collagen fibrils, and Ag NPs with a hydrodynamic diameter of more than 41 nm were completely trapped in an outer rim of the MCSs even after incubation for 48 h. In addition, we examined the impact of these NPs on essential elements (P, Fe, Cu, and Zn) in areas of Ag NP accumulation. We observed a linear increase at the sub-femtogram level in the total concentration of Cu (fg per pixel) in samples treated with small or large Ag NPs (∅ 5 nm or ∅ 50 nm) for 48 h. KW - Nanoparticle KW - Laser ablation KW - ICP-MS KW - Imaging KW - Cell PY - 2019 DO - https://doi.org/10.1039/c9an00856j SN - 0003-2654 VL - 144 IS - 16 SP - 4935 EP - 4942 PB - Royal Society of Chemistry RSC CY - Cambridge AN - OPUS4-48531 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drescher, D. A1 - Traub, Heike A1 - Büchner, T. A1 - Jakubowski, Norbert A1 - Kneipp, J. T1 - Properties of in situ generated gold nanoparticles in the cellular context JF - Nanoscale N2 - Gold nanostructures that serve as probes for nanospectroscopic analysis of eukaryotic cell cultures can be obtained by the in situ reduction of tetrachloroauric acid (HAuCl4). To understand the formation process of such intracellularly grown particles depending on the incubation medium, the reaction was carried out with 3T3 fibroblast cells in three different incubation media, phosphate buffer, Dulbecco's Modified Eagle Medium (DMEM), and standard cell culture medium (DMEM with fetal calf serum). The size, the optical properties, the biomolecular corona, and the localization of the gold nanoparticles formed in situ vary for the different conditions. The combination of surface-enhanced Raman scattering (SERS) and laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) microscopic mapping and transmission electron microscopy (TEM) provides complementary perspectives on plasmonic nanoparticles and non-plasmonic gold compounds inside the cells. While for the incubation with HAuCl4 in PBS, gold particles provide optical signals from the nucleus, the incubation in standard cell culture medium leads to scavenging of the toxic molecules and the formation of spots of high gold concentration in the cytoplasm without formation of SERS-active particles inside the cells. The biomolecular corona of nanoparticles formed in situ after incubation in buffer and DMEM differs, suggesting that different intracellular molecular species serve for reduction and stabilization. Comparison with data obtained from ready-made gold nanoparticles suggests complementary application of in situ and ex situ generated nanostructures for optical probing. KW - Nanoparticles KW - Laser ablation KW - ICP-MS KW - SERS KW - Cell PY - 2017 DO - https://doi.org/10.1039/C7NR04620K SN - 2040-3372 VL - 9 IS - 32 SP - 11647 EP - 11656 PB - The Royal Society of Chemistry RSC CY - Cambridge, UK AN - OPUS4-41871 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Arakawa, Akihiro A1 - Jakubowski, Norbert A1 - Flemig, Sabine A1 - Koellensperger, G. A1 - Rusz, M. A1 - Iwahata, D. A1 - Traub, Heike A1 - Hirata, T. T1 - High-resolution laser ablation inductively coupled plasma mass spectrometry used to study transport of metallic nanoparticles through collagen-rich microstructures in fibroblast multicellular spheroids JF - Analytical and Bioanalytical Chemistry N2 - We have efficiently produced collagen-rich microstructures in fibroblast multicellular spheroids (MCSs) as a three-dimensional in vitro tissue analog to investigate silver (Ag) nanoparticle (NP) penetration. The MCS production was examined by changing the seeding cell number (500 to 40,000 cells) and the growth period (1 to 10 days). MCSs were incubated with Ag NP suspensions with a concentration of 5 μg/mL for 24 h. For this study, laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was used to visualize Ag NP localization quantitatively. Thin sections of MCSs were analyzed by LA-ICP-MS with a laser spot size of 8 μm to image distributions of 109Ag, 31P, 63Cu, 66Zn, and 79Br. A calibration using a NP suspension was applied to convert the measured Ag intensity into the number of NPs present. The determined numbers of NPs ranged from 30 to 7200 particles in an outer rim of MCS. The particle distribution was clearly correlated with the presence of 31P and 66Zn and was localized in the outer rim of proliferating cells with a width that was equal to about twice the diameter of single cells. Moreover, abundant collagens were found in the outer rim of MCSs. For only the highest seeding cell number, NPs were completely captured at the outer rim, in a natural barrier reducing particle transport, whereas Eosin (79Br) used as a probe of small molecules penetrated into the core of MCSs already after 1 min of exposure. KW - Laser ablation KW - ICP-MS KW - Nanoparticle KW - Cell KW - Speroid PY - 2019 DO - https://doi.org/10.1007/s00216-019-01827-w SN - 1618-2642 SN - 1618-2650 VL - 411 IS - 16 SP - 3497 EP - 3506 PB - Springer CY - Berlin, Heidelberg AN - OPUS4-47900 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER - TY - JOUR A1 - Drescher, Daniela A1 - Giesen, Charlotte A1 - Traub, Heike A1 - Panne, Ulrich A1 - Kneipp, Janina A1 - Jakubowski, Norbert T1 - Quantitative imaging of gold and silver nanoparticles in single eukaryotic cells by laser ablation ICP-MS JF - Analytical chemistry N2 - Laser ablation inductively coupled plasma mass spectrometry (LA-ICP-MS) was utilized for spatially resolved bioimaging of the distribution of silver and gold nanoparticles in individual fibroblast cells upon different incubation experiments. High spatial resolution was achieved by optimization of scan speed, ablation frequency, and laser energy. Nanoparticles are visualized with respect to cellular substructures and are found to accumulate in the perinuclear region with increasing incubation time. On the basis of matrix-matched calibration, we developed a method for quantification of the number of metal nanoparticles at the single-cell level. The results provide insight into nanoparticle/cell interactions and have implications for the development of analytical methods in tissue diagnostics and therapeutics. KW - Imaging KW - Cell KW - Nanoparticles KW - Laser ablation KW - ICP-MS PY - 2012 DO - https://doi.org/10.1021/ac302639c SN - 0003-2700 SN - 1520-6882 VL - 84 IS - 22 SP - 9684 EP - 9688 PB - American Chemical Society CY - Washington, DC AN - OPUS4-27440 LA - eng AD - Bundesanstalt fuer Materialforschung und -pruefung (BAM), Berlin, Germany ER -