Nitrogen-rich quantum dots-based fluorescence molecularly imprinted paper strip for p-nitroaniline detection

摘要

In this work, a paper strip-based sensor was produced to detect p-nitroaniline with nitrogen-rich quantum dots (N-dots) and polydopamine molecularly imprinted polymer (MIP). In this sensing system, we used p-nitroaniline as a template to prepare the polydopamine/N-dots imprinted material by self-polymerization of dopamine. As a result, the captured p-nitroaniline quenched the fluorescence intensity of N-dots on the paper strip. The fluorescence intensity ratio of the sensor before and after the adsorption of p-nitroaniline was linearly related with the logarithmic concentration of p-nitroaniline within a certain range from 5 nmol L-1 to 1 mol L-1 with a quite low detection limit of 1.65 nmol L-1. It is the first time to detect p-nitroaniline reported with polydopamine/N-dots imprinted material with high selectivity.