School of Pharmacy, Nanjing Medical University, Nanjing, Jiangsu 211126, China.
State Key Laboratory of Analytical Chemistry for Life Science, School of Chemistry and Chemical Engineering, Nanjing University, Nanjing 210023, China.
Anal Chem. 2023 Jul 11;95(27):10172-10177. doi: 10.1021/acs.analchem.3c00114. Epub 2023 Jun 26.
The electrochemical visualization of proteins in the plasma membrane of single fixed cells was achieved with a spatial resolution of 160 nm using scanning electrochemical cell microscopy. The model protein, the carcinoembryonic antigen (CEA), is linked with a ruthenium complex (Ru(bpy))-tagged antibody, which exhibits redox peaks in its cyclic voltammetry curves after a nanopipette tip contacts the cellular membrane. Based on the potential-resolved oxidation or reduction currents, an uneven distribution of membrane CEAs on the cells is electrochemically visualized, which could only be achieved previously using super-resolution optical microscopy. Compared with current electrochemical microscopy, the single-cell scanning electrochemical cell microscopy (SECCM) strategy not only improves the spatial resolution but also utilizes the potential-resolved current from the antibody-antigen complex to increase electrochemical imaging accuracy. Eventually, the electrochemical visualization of cellular proteins at the nanoscale enables the super-resolution study of cells to provide more biological information.
利用扫描电化学池显微镜，实现了对单个固定细胞的质膜中蛋白质的电化学可视化，空间分辨率为 160nm。模型蛋白癌胚抗原（CEA）与钌配合物（Ru（bpy））标记的抗体相连，当纳米管尖端接触细胞膜后，其循环伏安曲线中出现氧化还原峰。基于电位分辨的氧化或还原电流，可以电化学可视化细胞上膜 CEA 的不均匀分布，这在以前只能通过超分辨率光学显微镜来实现。与当前的电化学显微镜相比，单细胞扫描电化学池显微镜（SECCM）策略不仅提高了空间分辨率，而且还利用抗体-抗原复合物的电位分辨电流来提高电化学成像的准确性。最终，在纳米尺度上对细胞蛋白质进行电化学可视化，使超分辨率研究细胞能够提供更多的生物学信息。
