A sensitive electrochemical sensing platform for the detection of Marbofloxacin using ZrMo2O8/MWCNT-COOH composites

Marbofloxacin (MAR) has been extensively used in both clinical and agricultural sectors to combat bacterial infections. Despite its therapeutic uses, MAR residues persist in the environment, causing serious adverse effects on human health and ecosystems. Therefore, developing a facile but reliable approach for the determination of MAR is of paramount importance. Herein, a sensitive electrochemical sensing platform was established for the determination of trace amounts of MAR using ZrMo 2 O 8 /carboxylated multiwalled carbon nanotubes (MWCNT-COOH). The synergistic effect between the catalytic ZrMo 2 O 8 and the conductive MWCNT-COOH generate numerous active sites and enhanced electron transfer, significantly boosting peak current response of MAR. As consequence, the ZrMo 2 O 8 /MWCNT-COOH exhibited remarkably catalytic activity toward MAR oxidation over a wide concentration range (0.01−10 μM), with an ultrahigh sensitivity (7.640 μA μM −1 ) and a low detection limit (0.002 μM). The ZrMo 2 O 8 /MWCNT-COOH showcased the strong anti-interfering ability against the excess of potential interfering substances, and could record stable response peak current for at least 15 days. MAR concentrations in veterinary drug tablets and livestock effluent were accurately quantified by using the ZrMo 2 O 8 /MWCNT-COOH/GCE with good recovery. Considering its attractive merits including low cost, ultrahigh sensitivity, and strong anti-interfering ability, the ZrMo 2 O 8 /MWCNT-COOH/GCE demonstrates promising prospects on the trace determination of MAR residues in various complicated matrices.