Electrochemical sensor based on Pd@Nb₂C nanocomposites for rapid and sensitive detection of ciprofloxacin

This study introduced an electrochemical sensor for the rapid, sensitive, and accurate detection of ciprofloxacin (CIP). The sensor utilized a screen-printed carbon electrode (SPCE) modified with Pd@Nb₂C nanocomposites, which were prepared through the in-situ reduction of palladium nitrate on Nb₂C nanosheets, resulting in a uniform distribution of Pd nanoparticles. Subsequently, they were drop-coated onto the SPCE surface, forming a Pd@Nb₂C/SPCE electrochemical sensing platform. The electrochemical analysis demonstrated the excellent electrochemical performance of the sensor. Pd@Nb₂C/SPCE showed a consistent linear correlation between redox peak current (I_P) and CIP concentration (c_CIP) in the range of 10–150 μmol/L, boasting a detection limit of 3 μmol/L. Notably, this technique tracked CIP in both whole and skimmed milk, achieving a high recoveries of 96.36%–105.40% (n = 3). Moreover, the sensor exhibited exceptional selectivity towards CIP, remaining unaffected by various interferences such as sulphonamide, amoxicillin, tetracycline, and chloramphenicol. These findings hold enormous promise for enabling real-time and rapid monitoring of CIP in milk.