TY - GEN A1 - Laurinavichyute, Veronika K. A1 - Nizamov, Shavkat A1 - Mirsky, Vladimir M. T1 - The Role of Anion Adsorption in the Effect of Electrode Potential on Surface Plasmon Resonance Response T2 - ChemPhysChem : a European journal of physical chemistry and chemical physics N2 - Surface plasmon resonance, being widely used in bioanalytics and biotechnology, is influenced by the electrical potential of the resonant gold layer. To evaluate the mechanism of this effect, we have studied it in solutions of various inorganic electrolytes. The magnitude of the effect decreases according to the series: KBr>KCl>KF>NaClO4. The data were treated by using different models of the interface. A quantitative description was obtained for the model, which takes into account the local dielectric function of gold being affected by the free electron charge, diffuse ionic layer near the gold/water interface, and specific adsorption of halides to the gold surface with partial charge transfer. Taking into account that most biological experiments are performed in chloride-containing solutions, detailed analysis of the model at these conditions was performed. The results indicate that the chloride adsorption is the main mechanism for the influence of potential on the surface plasmon resonance. The dependencies of surface concentration and residual charge of chloride on the applied potential were determined. Y1 - 2017 U6 - https://doi.org/10.1002/cphc.201601288 SN - 1439-7641 SN - 1439-4235 VL - 18 IS - 12 SP - 1552 EP - 1560 ER - TY - CHAP A1 - Scherbahn, Vitali A1 - Nizamov, Shavkat A1 - Mirsky, Vladimir M. ED - Schöning, Michael J. ED - Poghossian, Arshak T1 - Toward ultrasensitive surface plasmon resonance sensors T2 - Label-free biosensing : advanced materials, devices and applications N2 - Despite the history of application of surface plasmon resonance (SPR) for chemo- and biosensing being over 30 years long, the development of this technique is still in progress. This review is focused on the technological aspects of further improvement of analytical performance of SPR transducers based on Kretschmann configuration. We describe basic measurement configurations, their improvements and optimizations, and their drawbacks and limitations. An importance of referencing in SPR sensors is highlighted. The referencing approaches are classified into the following domains: (1) macroscopic spatially separated referencing, (2) self-referencing based on micro-patterning, (3) in-place referencing, (4) spatiotemporal referencing, and (5) electrochemically assisted referencing. The underlying principles of these approaches, examples of their implementation, and resulting improvements of sensor performance are described. Finally, an analysis of SPR data and an extraction of affinity properties are discussed. KW - Self-referencing KW - Surface plasmon resonance KW - Surface plasmon resonance microscopy Y1 - 2018 SN - 978-3-319-75220-4 SN - 978-3-319-75219-8 U6 - https://doi.org/https://doi.org/10.1007/5346_2017_21 SP - 409 EP - 448 PB - Springer CY - Cham ER - TY - GEN A1 - Tonder, Karin A1 - Nizamov, Shavkat A1 - Scherbahn, Vitali A1 - Mirsky, Vladimir M. T1 - Das Unsichtbare im Blick Ultrasensitive Detektion, Quantifizierung und Identifizierung industriell erzeugter und biologischer Nanopartikel T2 - Laborpraxis Y1 - 2018 UR - https://files.vogel.de/vogelonline/vogelonline/issues/lp/8263.pdf SN - 0344-1733 VL - 42 IS - 1 SP - 24 EP - 26 ER - TY - CHAP A1 - Nizamov, Shavkat A1 - Mirsky, Vladimir M. ED - Kumar, Challa S. S. R. T1 - Wide-field Surface Plasmon Resonance Microscopy for in-situ Characterization of Nanoparticle Suspensions T2 - In-situ characterization techniques for nanomaterials Y1 - 2018 SN - 978-3-662-56322-9 SN - 978-3-662-56321-2 U6 - https://doi.org/10.1007/978-3-662-56322-9 SP - 61 EP - 106 PB - Springer Verlag CY - Heidelberg ER - TY - GEN A1 - Laurinavichyute, Veronika K. A1 - Nizamov, Shavkat A1 - Mirsky, Vladimir M. T1 - Real time tracking of the early stage of electrochemical nucleation T2 - Electrochimica Acta N2 - An analysis of early stage of electrochemical nucleation is crucial in order to understand the mechanism of this process and for electrochemical synthesis of new materials. We show here an application of the wide field surface plasmon microscopy (WF-SPRM) for this purpose. It allows us in-situ monitoring of the growth of nuclei in the range from ~20 till over 1000 nm. The system registers the moment and the place of the formation of each individual nucleus for the total number of the tracked nuclei up to ~10,000 per 1 mm2. The results demonstrate that the integral information obtained from electrochemical measurements can be extracted quantitatively from optical measurements while optical data provide also information on the size of each individual nucleus, individual nucleation time, localization and growth kinetics, and allows one to distinguish the rate limiting stage for each individual nucleus. In this work WF-SPRM was applied for investigation of electrochemical deposition of copper on gold, but this technique can be extended easily to other materials or other nucleation types. KW - Surface plasmon resonance microscopy KW - Nucleation and growth KW - Copper deposition KW - Growth kinetics KW - Diffusion zones Y1 - 2021 U6 - https://doi.org/10.1016/j.electacta.2021.138278 SN - 0013-4686 VL - 382 ER - TY - GEN A1 - Nizamov, Shavkat A1 - Dimchevska Sazdovska, Simona A1 - Mirsky, Vladimir M. T1 - A review of optical methods for ultrasensitive detection and characterization of nanoparticles in liquid media with a focus on the wide field surface plasmon microscopy T2 - Analytica Chimica Acta N2 - Development of nanotechnology and corresponding industries during the last decade resulted in a new challenge for analytical science. This includes an ultrasensitive detection and characterization of nanoparticles of different origin and other nanomaterials in various media, including so complex ones as food, biological or environmental samples. The goal of this review is a systematic analysis of possible approaches and description of physical principles behind these methods. The main attention is paid to optical methods which are considered by authors to be mostly effective for the formulated task. Different approaches for detection and analysis of nanoparticles in a volume as well as of those adsorbed on a surface are discussed. While the technologies based on direct analysis of nanoparticle suspensions belong to the established approaches whose development potential has been in large extent exhausted, the novel technologies based on the surface sensing of adsorbed nanoparticles demonstrate intensive development. Therefore, the final part of the review is focused on the wide-field surface plasmon resonance microscopy. It allows one an ultrasensitive detection and characterization of individual nanoparticles of different origin in complex media and provides numerous possibilities for subsequent chemical identification of the detected particles using a hyphenation with other analytical technologies. KW - Nanoparticles KW - Detection of nanoparticles KW - Characterization of nanoparticles KW - Optical techniques KW - Surface plasmon resonance microscopy KW - Nanoparticle tracking analysis Y1 - 2022 U6 - https://doi.org/10.1016/j.aca.2022.339633 SN - 1873-4324 VL - 1204 ER - TY - GEN A1 - Nizamov, Shavkat A1 - Scherbahn, Vitali A1 - Mirsky, Vladimir M. T1 - Detection of Single Sub-Micrometer Objects of Biological or Technical Origin Using Wide Field Surface Plasmon Microscopy T2 - MDPI Proceedings (Journal), Proceedings of the 5th International Symposium on Sensor Science (I3S 2017)) N2 - Detection of nano- and microparticles is an important task for chemical analytics, medical diagnostics, food industry, biotechnology, environmental monitoring and many other fields of science and industry. For this purpose, a method based on the detection and analysis of minute signals of surface plasmon resonance images due to adsorption of single particles was developed. The new technology allows one a real-time detection of interaction of single nano- and microparticles of different origin with sensor surface. Adsorption of each nanoparticle leads to a characteristic diffraction image whose intensity depends on the size and chemical composition of the particle. The number of the nanoparticle - surface binding events per time and surface area characterizes volume concentration. A large monitored surface area of the sensor surface allows one to detect many hundreds events in each frame or totally up to a million particles on the sensor surface, this leads to a very high dynamic range of counting and to a correspondingly high dynamic range in the concentration scale. Depending on the type of particles and experimental conditions, the detection limit for aqueous samples can be below 1000 nanoparticles per microliter. Stable analysis of nanoparticles in very complex environment (fruit juices, wines, cosmetic formulations) was demonstrated. For determination of chemical composition of single nanoparticles separately, the wide field surface plasmon microscopy can be used as a tandem technique. For example, for analysis of technical nanoparticles it can be assisted by electrochemical analysis. In this case, the gold sensor surface is used both for plasmon microscopy and as a working electrode of electrochemical cell. Applying a linear potential sweep to this electrode, adsorbed nanoparticles can be subjected to an electrochemical conversion leading to the change of their refractive index; the value of electrical potential of this conversion characterizes material of the particular nanoparticle. Notably, such analysis is performed simultaneously but independently for each adsorbed particle. The method of wide filed surface plasmon microscopy can be applied for ultrasensitive detection and analysis of nano- and microparticles of biological (bacteria, viruses, exosomes), biotechnological, (liposomes, protein nanoparticles for drug delivery) or technical (metallic, oxides, plastic, etc.) origin. Y1 - 2017 UR - https://www.mdpi.com/2504-3900/1/8/788 U6 - https://doi.org/10.3390/proceedings1080788 VL - 1 IS - 8 PB - MDPI CY - Basel, Switzerland ER - TY - GEN A1 - Kolosova, Olga S. A1 - Efremenko, Yulia A1 - Laurinavichyute, Veronika K. A1 - Nizamov, Shavkat A1 - Petrushenko, Serhii I. A1 - Mirsky, Vladimir M. T1 - Poly-3-thienylboronic Acid Nanoparticles: Synthesis, Characterization, and Interaction with Saccharides Studied at the Level of Individual Nanoparticles T2 - ACS Applied Nano Materials N2 - Polythiophenboronic acid (PThBA) combines an affinity for saccharides with the unique properties of conducting polymers. This polymer was synthesized by enzymatic catalyzed oxidative polymerization, characterized by UV–vis spectroscopy in solvents of different polarity and by 1H NMR. A suspension of PThBA nanoparticles (PThBA NPs) was prepared by injecting a methanol solution of PThBA into an aqueous electrolyte. PThBA NPs were characterized by scanning electron microscopy. Nanoparticle tracking analysis and dynamic light scattering were used to study the concentration of the particles and the particle size distribution. The effect of pH on these properties was analyzed and an increase in nanoparticle size was observed at alkaline pH. This effect was explained by electrostatic swelling of the nanoparticles. Measurements of ζ-potentials in the wide pH range showed the presence of acidic groups with a pKa of 8.6; the value of the surface charge at the conditions of maximal deprotonation of these groups was estimated to be ∼70 mC/m2. Changes in the optical spectra of PThBA NPs due to variations in pH and additions of organic solvents indicate transformations between twisted and planar conformations of the polymer backbone. The binding of saccharides by PThBA NPs resulted in a decrease in the size and charge of the nanoparticles. Recently developed wide-field surface plasmon resonance microscopy (WF-SPRM) can simultaneously monitor every single nanoparticle among many thousands adsorbed on a surface. It was used for the first time to study chemosensitive nanoparticles. The described above effects of pH change and saccharide binding described above, monitor were confirmed by using integral techniques in monitoring individual nanoparticles, by WF-SPRM. The pH effects were shown to be reversible. An increase in the affinity of PThBA NPs for saccharides at a more alkaline pH was also observed. A fast recovery of polymer binding sites by a pH decrease was demonstrated. The synthesized and characterized PThBA NPs can be further used for various purposes including analytical assays, chemical sensors, or chemosensitive nanotechnological devices. KW - - KW - conducting polymers KW - chemosensitive nanoparticles KW - saccharides binding KW - affinity control KW - polythienylboronic acid KW - surface plasmon resonance microscopy Y1 - 2024 U6 - https://doi.org/10.1021/acsanm.4c00216 SN - 2574-0970 VL - 7 IS - 10 SP - 11120 EP - 11135 PB - American Chemical Society ER - TY - GEN A1 - Snopok, Borys A. A1 - Nizamov, Shavkat A1 - Snopok, Tetiana V. A1 - Mirsky, Vladimir M. T1 - Agglomeration compaction promotes corrosion of gold nanoparticles T2 - Nanoscale Advances N2 - Engineered nanoparticles are increasingly being used in various areas of human activity. However, the degradation mechanism of nanobodies in harsh environments is still a puzzle for theory and experiment. We report here the results of optical spectroscopy and nanoparticle tracking analysis, quantifying agglomeration and sizing of 50 nm citrate stabilized gold nanoparticles (GNPs) in HCl solutions containing H2O2. The mechanism of a consecutive corrosion reaction of GNPs is discussed within the framework of the near-field approach. We found that the disappearance of single nanoparticles from a suspension does not occur due to their dissolution per se, but is a consequence of the formation of aggregates. The neutralization of electrostatic shielding at high ionic strength allows gold nanoparticles to approach the subnanometer distance within the region of capping defects, at which the Casimir and van der Waals attractive forces dominate. It is suggested that electric field fluctuations in the confined space between highly conductive gold nanoparticles cause complexant-stimulated loss of metal from the core in the contact area. Going beyond the charge screening limitations by constraining the reaction space and reducing the double electrical layer thickness allows for chemical processes flow along otherwise not accessible reaction pathways. Y1 - 2024 U6 - https://doi.org/10.1039/D4NA00109E SN - 2516-0230 VL - 6 IS - 15 SP - 3865 EP - 3877 PB - Royal Society of Chemistry (RSC) ER - TY - GEN A1 - Laurinavichyute, Veronika K. A1 - Nizamov, Shavkat A1 - Mirsky, Vladimir M. T1 - Cyclic voltarefractometry of single TiO₂ nanoparticles in large ensembles in nonaqueous electrolyte T2 - Analytical chemistry N2 - Single nanoparticle (NP) cyclic voltarefractometry (CVR), realized as wide-field surface plasmon resonance microscopy (SPRM) in combination with potential cycling, has been proposed and applied to the in situ study of TiO₂ NPs. Electrochemical activity of TiO₂ is mainly observed outside the electrochemical stability window of water. Therefore, the response of individual anatase (a-TiO₂) and rutile (r-TiO₂) NPs adsorbed on a gold layer was studied in 0.25 M LiClO4 acetonitrile solutions. The use of acetonitrile allows us to exploit a much wider potential window compared to water, while due to the almost identical refractive index (nD = 1.344 and 1.333 for acetonitrile and water, respectively), the conditions of the SPR are not changed. This greatly expands the variety of electrochemical reactions that can be studied by SPR techniques. Cyclic polarization of a-TiO₂ and r-TiO₂ NPs results in pronounced electrochemical and optical responses around −1.55 V and around −1.8 V vs Fc+/Fc, respectively. This specific optoelectrochemical response allows them to be distinguished from other NPs. Based on this difference in characteristic potentials, a mixture of a-TiO₂ and r-TiO₂ NPs can be analyzed by CVR as well. The proposed correction algorithm compensates for the drift in the SPRM background caused by the accompanying formation of insoluble compounds and separates the optical response of the NPs out of the background. The results obtained in the study of this complex system demonstrate the capabilities of the developed analytical method. The CVR can be applied to the quantitative analysis of many other types of NPs in nonaqueous solutions, providing information on the electrochemical properties of each individual particle on the electrode surface. Y1 - 2025 U6 - https://doi.org/10.1021/acs.analchem.4c04181 SN - 0003-2700 SN - 1520-6882 VL - 97 IS - 2 SP - 1160 EP - 1169 PB - American Chemical Society CY - Washington, D.C. ER -