Electrochemical Detection of Oxytetracycline employing Sugarcane Carbon modified Graphite Electrode

Oxytetracycline (OTC) is an antibiotic and belongs to contaminants of emerging concern seriously impacting human health, which makes necessary to develop a simple, fast, sensitive, and low-cost detection technology to detect OTC in the environment, and electrochemical sensors have these advantages. This study used CeO 2 -Co 3 O 4 quantum dots@porous carbon/multi-walled carbon nanotube (CeO 2 -Co 3 O 4 QDs@PC/MWCNT/GE) composites to modify graphite electrodes to fabricate high-sensitivity electrochemical sensors. The quantum dots were made from waste sugarcane-bagasse. In order to evaluate its performance, scanning electron microscopy, energy-dispersive X-ray spectroscopy, Fourier-transform infrared spectroscopy, X-ray diffractometer, Raman spectroscopy, cyclic & differential pulse voltammograms, electrochemical impedance spectroscopy, and other instrumental analysis were performed. The results showed that the CeO 2 -Co 3 O 4 QDs@PC/MWCNT/GE had excellent performance for OTC detection, and its linear calibration range was 1.007 × 10 -8 M to 2.04 × 10 -7 M (i.e., 0.005 – 0.1 ppm) and 1.007 × 10 -6 M to 1.209 × 10 -4 M (i.e., 0.5 – 60 ppm). The limit of detection and limit of quantification were 1.23 nM (0.61 ppb) and 4.09 nM (2.03 ppb) (S/N = 3), respectively. This method provides a new way to prepare electrochemical sensors for OTC detection.