Sensitive determination of ciprofloxacin with a light-driven photoelectrochemical sensor based on Cu2O/g-C3N4 heterojunctions

Abstract

Ciprofloxacin (CFX) has excellent bactericidal and antimicrobial properties and is widely used in dairy cattle husbandry. Due to metabolic effects, there is often a certain residue in milk, even a trace amount will pose a threat to humans. Therefore, its facile and sensitive detection is of significant importance. Herein, Cu2O/g-C3N4 heterojunction has been synthesized and its photoelectrochemical (PEC) properties and electron transfer mechanism have been studied. The use of visible light can significantly improve the efficiency of electron migration and the separation of photogenerated electron hole pairs, thus showing higher photoelectric performance for the detection of CFX. In the range of 5.0 ~1000.0ng·L-1, the current of Cu2O/g-C3N4 is linearly related to the concentration of CFX and the detection limit is 1.5ng·L-1. PEC sensor has good long-term stability and selectivity. The practical application of this method is verified by testing commercial samples. Thus, this research provides a feasible PEC sensing platform for routine analysis of other antibiotics in practice.