In Situ Study of the Drug–Target Protein Interaction in Single Living Cells by Combining Fluorescence Correlation Spectroscopy with Affinity Probes

) values in living cells and in solutions, suggesting it is quite necessary to evaluate the drug-target interactions in living cells. Compared with current methods, our approach can be used to in situ and real-time study the drug-target interaction in living cells, and it may become a promising and universal tool for in situ drug research at molecular level.