Quinoxaline-based conjugated microporous polymer-grafted graphene sensors for the sensitive detection of rifampicin

The sensitive and accurate detection of rifampicin (RIF), a common antibiotic, is of primary importance for infection control. This paper reports the novel application of a synthesized quinoxaline-based conjugated microporous polymer-grafted graphene (CMP-rGO) in a photoelectrochemical (PEC) sensor for RIF detection. The results revealed that CMP-rGO had a large surface area (620.506 m2·g−1) and good PEC performance. Moreover, CMP-rGO has good photocurrent when the working voltage was −0.2 V (vs Ag/AgCl). The effects of the pH, light source, and coating amount on the response of PEC to RIF were investigated. Furthermore, the CMP-rGO-based PEC sensor revealed a satisfactory response to RIF in the 0.25 ∼ 500 μM range with a detection limit of 0.067 μM, and exhibited good repeatability, stability, and selectivity. This established method was applied for the quantitative analysis of RIF in rifampicin capsules, human serum, and urine samples, and satisfactory results were obtained. Consequently, this novel PEC sensor enables the sensitive detection of RIF and offers perspectives for novel applications of conjugated microporous polymers.