A novel fluorescent sensor for rifampicin based on the bio-inspired molecularly imprinted polymer-AgInS 2 /ZnS quantum dots

Abstract

Abstract A fluorescent sensing material based on the ternary core-shell quantum dots with outstanding optical properties and a bio-inspired molecularly imprinted polymer (MIP) as a recognition element has been prepared for selective detection of rifampicin (RFP). Firstly, AgInS2/ZnS core/shell quantum dots (ZAIS QDs) were synthesized by a hydrothermal process. Then, the fluorescent sensor was prepared by coating these QDs by a dopamine-based MIP layer. The fluorescence of MIP@ZAIS QDs was quenched by RFP as a result of the photoinduced electron transfer process. The quenching constant was much higher for MIP@ZAIS QDs than the non-imprinted polymer@QDs, indicating that MIP@ZAIS QDs could selectively recognize RFP. Under the optimized conditions, the sensor had a good linear relationship at the RFP concentration range of 5.0 to 300 nM and the limit of detection was 1.25 nM. It also showed good recoveries ranging from 98–101%, for analysis of human plasma samples. The method is simple and effective for the detection of RFP and offers a practical application for the rapid investigation of human plasma samples.