Biocompatible fluorescent nanocrystals for immunolabeling of membrane proteins and cells

摘要: A methodology for simple convenient preparation of bright, negatively or positively charged, water-soluble CdSe/ZnS core/shell nanocrystals (NCs) and their stabilization in aqueous solution is described. Single NCs can be detected using a standard epifluorescent microscope, ensuring detection limit one molecule coupled with an NC. solubilized water by DL-Cys were stabilized, to avoid aggregation, poly(allylamine) conjugated polyclonal anti-mouse antibodies (Abs). NC-Abs conjugates tested dot-blots exhibited retention binding capacity within several nanograms antigen detected. We further demonstrated the advantages immunofluorescent three-dimensional (3D) confocal analysis p-glycoprotein (p-gp), main mediators MDR phenotype, overexpressed membrane MCF7r breast adenocarcinoma cells. Immunolabeling p-gp was 4200-, 2600-, 420-fold more resistant photobleaching than its labeling fluorescein isothiocyanate-Abs, R-phycoerythrin-Abs, AlexaFluor488-Abs, respectively. The highly specific, data used reconstruction 3D images distribution cell membrane. Finally, we applicability obtained method described specific antigens paraffin-embedded formaldehyde-fixed cancer tissue specimens, immunostaining cytokeratin skin basal carcinoma as example. conclude that may serve easy-to-do, sensitive, photostable labels analysis, immunohistochemical detection, studies proteins