In-situ growth of cobalt nanoparticles for naked-eye determination of tetracyclines in water, milk, and honey

This study describes the in-situ growth of cobalt nanoparticles (Co NPs) to a naked-eye determination of tetracycline antibiotics in the water, honey, and milk samples as a colorimetric method. Tetracycline antibiotics bonded cobalt NPs (CoNPs-TCs) are performed light green to yellow color with high UV-vis absorbance at lambda maximum of 400 nm. Cobalt nanoparticles bonded tetracycline were characterized by using UV-vis spectroscopy, Fourier transforms infrared spectroscopy (FT-IR), transmission electron microscopy (TEM), and field-emission scanning electron microscopy (FE-SEM). Effective parameters of the method, such as solution pH (similar to 8.5), reaction time (3 min), temperature (25 degrees C), and cobalt concentration (20 mu gmL(-1)) were studied. Analytical validation is performed that the limit of determination 0.21-1.09 mu gmL(-1) and the limit of quantification was 0.73-3.88 mu gmL(-1) with a matrix match linear dynamic range from 1 to 100 mu gmL(-1) for tetracyclines in all water, milk, and honey samples. The accuracy and precision of the method were evaluated with real samples recovery (80-108%, +/- 5) and precision (intraday, 0.73-3.75 %, n = 3 and interday, 2.01-4.82%, n = 9), respectively. This method provides a rapid, simple, and inexpensive detection with acceptable sensitivity.