Detection, identification and characterization of single nanoparticles based on plamonic visualization of their electrochemical dissolution
Final Report Abstract
Wide-field surface plasmon resonance microscopy (WF-SPRM) is an ultrasensitive technique for the detection, quantification and monitoring of individual nanoparticles (NPs) on its sensor surface. By using its sensor surface as working electrode in electrochemical setup (further we name this approach as [cyclic] voltarefractometry), it is possible to perform optical monitoring on individual NPs and their electrochemical conversions. Electrochemical potential window was extended by using non-aqueous electrolyte (acetonitrile). NPs of anatase (a-TiO2), rutile (r-TiO2), LiFePO4-NPs and few others were studied. The in situ cyclic polarization of a- TiO2 and r-TiO2 NPs adsorbed on gold-coated prism results in pronounced optical responses in the adsorption spots around -1.55 V and around -1.8 V vs Fc+/Fc, respectively which correspond to the redox potential obtained by electrochemical measurements. Voltarefractometric response of mixtures of a-TiO₂ and r-TiO₂ NPs can be separated into a weighted sum of their mean responses. Potential cycling in the wide potential range in LiClO4 solutions in ACN leads to irreversible passivation of the sensor. This phenomenon is attributed to the formation and deposition of various Li/H2O/O2 products which are insoluble in ACN. An algorithm of optical background correction under the conditions of a passive layer formation permitted the compensation of severe signal distortion and drifts was developed. The approach can be extended to other nanoscale processes like a formation of a new thin solid-electrolyte interface. The developed approach of optical analysis of electrochemical reactions opens the way for chemical identification of large populations of individual NPs by their electrochemical redox reaction within a broad potential range. It was applied for monitoring of Li ions intercalation into LiFePO4 NPs. The linear dependence of peak current/image intensity on square root of scan rate indicates diffusion-controlled process of Li intercalation into NPs. Thus, the charging/discharging of individual LiFePO4 “nanobatteries” was observed. Characteristic potential values provide an identification of the nanomaterial. Other nanoscale reactions, like NP response to their chemical environment, can be used for analytical purposes by the same way. Monitoring of the response of chemosensitive NPs to the changes of pH and binding of saccharides were studied. pH-titration at the level of individual NPs was performed. Reversible and pH-dependent binding of saccharides to these NPs was demonstrated. Exploiting of WF-SPRM in ultrasensitive ELISA was shown. The results demonstrate, that the monitoring of chemically and electrochemically induced transitions using WF-SPRM is a promising approach for physicochemical analysis at the level of individual NPs for various analytical applications. The project results were presented in four papers, and others were submitted.
Publications
-
Real time tracking of the early stage of electrochemical nucleation. Electrochimica Acta, 382, 138278.
Laurinavichyute, Veronika K.; Nizamov, Shavkat & Mirsky, Vladimir M.
-
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. Analytica Chimica Acta, 1204, 339633.
Nizamov, Shavkat; Sazdovska, Simona Dimchevska & Mirsky, Vladimir M.
-
Agglomeration compaction promotes corrosion of gold nanoparticles. Nanoscale Advances, 6(15), 3865-3877.
Snopok, Borys A.; Nizamov, Shavkat N.; Snopok, Tetiana V. & Mirsky, Vladimir M.
-
Poly-3-thienylboronic Acid Nanoparticles: Synthesis, Characterization, and Interaction with Saccharides Studied at the Level of Individual Nanoparticles. ACS Applied Nano Materials, 7(10), 11120-11135.
Kolosova, Olga S.; Efremenko, Yulia; Laurinavichyute, Veronika K.; Nizamov, Shavkat; Petrushenko, Serhii I. & Mirsky, Vladimir M.
