Potential of cobalt ferrite-graphitic carbon nitride nanocomposite in trace determination of pyrene as one of the priority pollutants in water and food samples

Abstract

In this research, cobalt ferrite-graphitic carbon nitride (CoFe₂O₄/GC₃N₄) nanocomposite with high extraction ability, high sensitivity, and strong magnetic properties was successfully synthesized and evaluated as a sorbent for ultrasound-assisted dispersive magnetic micro-solid phase extraction (UA-DM-μ-SPE) of pyrene (Py) in food and water samples. A successful synthesis of CoFe₂O₄/GC₃N₄ was inspected by Fourier transform infrared spectroscopy (FT-IR), X-ray diffraction (XRD), field emission scanning electron microscope (FE-SEM), energy-dispersive X-ray spectrometry (EDXS), and vibrating sample magnetometer (VSM) techniques. The experimental parameters affecting the UA-DM-μ-SPE efficiency, such as the amount of sorbent, pH, adsorption time, desorption time, and temperature, were effectively investigated according to a multivariate optimization approach. Under the optimal conditions, the detection limit, quantification limit, and relative standard deviation (RSD) for the target analyte were achieved at 2.33 ng mL^-1, 7.70 ng mL^-1, and 3.12%, respectively. The CoFe₂O₄/GC₃N₄ based UA-DM-μ-SPE followed by spectrofluorometry confirmed favorable results for the convenient and efficient determination of Py in the samples of vegetable, fruit, tea, and water.

Keywords: Cobalt ferrite; Food and water samples; Graphitic carbon nitride; Multivariate optimization; Nanocomposite; Pyrene.