Molecularly imprinted photoelectrochemical sensing platform based on g-C3N4/MOFs photoresponsive oxidase mimic for norfloxacin detection

Abstract

A molecularly imprinted photoelectrochemical sensor was successfully designed for sensitive detection of norfloxacin (NOR) based on poly (o-phenylenediamine) (PoPD) sensitized g-C3N4/Zr-MOFs(Fe) composite. Herein g-C3N4/Zr-MOFs(Fe) heterojunction composite was explored as photoresponsive oxidase mimic and photoactive material for the purpose of enhancing photoelectrochemical performances. In addition, PoPD molecularly imprinted polymers (MIPs) were introduced not only to act as the recognition element for selective performance, but also to possess photosensitive effect, which enhanced the photocurrent of sensor. SEM, element mapping method, XRD, UV–Vis and electrochemical impedance spectroscopy were employed for the characterization of the structural, chemical composition, optical and electrical properties of g-C3N4/Zr-MOFs(Fe) composite. Thanks to the photoresponsive oxidase mimic property and the selectivity of MIPs, the as-prepared sensor presented a good linear range of from 1.0 × 10−8 mol/L to 2.0 × 10−6 mol/L with NOR and a limit of detection of 5.7 × 10−9 mol/L. Moreover, the sensor platform has been proved to have excellent selectivity and real sample application.