Simultaneous analysis of chloramphenicol, amoxicillin, and enrofloxacin using electrochemical sensors with multilayer graphene electrodes fabricated by electrochemical methods in an organic solvent

Abstract

In this study, three antibiotics, chloramphenicol (CAP), amoxicillin (AMX), and enrofloxacin (ENR), were simultaneously analysed for the first time using electrochemical sensors. The multilayer graphene electrode used in the sensor was directly and rapidly fabricated from graphite through a onestep chronoamperometry method. Scanning electron microscopy and cyclic voltammetry techniques revealed the multilayer-graphene nanostructure of the prepared electrode with a large electrochemically active surface area and good electrochemical activity. The electrode exhibited the best electrochemical oxidation signals corresponding to the three antibiotics when fabricated at a potential of 5 V for 20 s. Under optimised conditions, the sensor demonstrated excellent multi-analyte analysis capability, with clear separation and good linearity of the signals of the three antibiotics (R²>0.99) in relation to their concentrations. The sensor exhibited high accuracy and sensitivity with detection limits of 0.060, 0.381, and 0.109 μM for CAP, AMX, and ENR, respectively. The applicability of the sensor was demonstrated through acceptable recoveries of all three antibiotics when simultaneously analysed in a lake water sample.