Single Molecular Functionalized Gold Nanoparticles for Hydrogen-Bonding Recognition and Colorimetric Detection of Dopamine with High Sensitivity and Selectivity

In this work, we developed a low-cost, facile, sensitive, and selective colorimetric method for the quantitative determination of dopamine, based on 4-amino-3-hydrazino-5-mercapto-1,2,4-triazol (AHMT) functionalized gold nanoparticles (AHMP-AuNPs) as a model probe. Dopamine could induce the aggregation of the AHMT-AuNPs through hydrogen-bonding interactions, which caused the colloidal solution changed from red to blue. And the color change was in situ monitored for the quantitative determination of dopamine in human serum and urine samples. The developed approach is simple, without using complex financial instruments and adding other metal salts or ions for improving sensitivity.