Abstract
Oxytetracycline is a broad-spectrum antibiotic used in animal husbandry that may cause the occurrence of antibiotic residues in food-producing animals. A detailed study of the electrochemical properties of oxytetracycline was carried out at montmorillonite and acetylene black modified carbon paste microelectrode. The oxytetracycline underwent an irreversible oxidation at montmorillonite-acetylene black/carbon paste microelectrode, which was an adsorption-controlled process with one proton and one electron. Using differential normal pulse voltammetry with accumulation at a fixed potential of 0.3 V for 120 s, oxytetracycline yielded a well-defined voltammetric response at 0.6 V in pH 7.4 citric acid–Na2HPO4 buffer. Furthermore, the oxidation peak current of oxytetracycline at the montmorillonite–acetylene black/carbon paste microelectrode linearly increased with concentration in the range of 0.5–50 µM with a low detection limit of 87 nM (S/N = 3). This methodology was successfully applied to the determination of oxytetracycline from food samples, suggesting that it has practical applications in monitoring oxytetracycline.
ACKNOWLEDGMENT
The authors declare there are no conflicts of interest. This article does not contain any studies with human or animal subjects.
Notes
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