Visualization of Mycotoxins in Living Cells Using Conformation-Resolved Aptamer Nanoprobes

Mycotoxins are the most toxic component and pose a major threat to human health. Monitoring mycotoxins in living cells is essential for their toxicology research; however, tools for the live-cell imaging of mycotoxins remain unexplored. Herein, we proposed a conformation-resolved aptamer nanoprobe (cresAptamer), allowing us to image mycotoxins in living cells. cresAptamer endows a dual recognition mechanism: binding-induced detachment from nanocarriers and response of intrinsic G-quadruplex of aptamers. The dual recognition mechanism allows us to resolve conformations of aptamer probes corresponding to nonspecific binding and target binding, thus sufficiently supporting the specific identification of target molecules in a complex matrix. cresAptamer significantly improved the signal-to-background ratio for detecting ochratoxin A (OTA), thus allowing us to sensitively and robustly image ochratoxin A in living cells. cresAptamer would be a facile tool for dynamically investigating the toxicology of mycotoxins at the single-cell level.