Synthesis of Fe3O4@SiO2-creatine as a new nanosorbent for dispersive magnetic solid-phase microextraction of copper ions from water, food, and soil samples

Abstract

For the first time, Fe3O4@SiO2-creatine (Fe3O4@SiO2-CRT) was synthesized and exploited as a nanosorbent in the dispersive magnetic solid phase microextraction (D-MSPμE) of copper from water, food, and agricultural soil samples. Flame atomic absorption spectrometry was employed for the quantification of concentration of Cu(II) ions subsequent to the elution process. Different techniques, including X-ray diffraction, fourier transform infrared, field emission scanning electron microscopy, and vibrating sample magnetometer, were utilized to characterize the synthesized nanosorbent. The factors influencing the efficiency of the extraction process were investigated and optimized. Under the optimal conditions (solution pH, 7.0; nanosorbent quantity, 20 mg; adsorption time, 7.0 min; desorption time, 2.0 min; and desorption agent, HNO3 0.5 mol L−1), the proposed method provided a wide linear range (5.0–125 ng mL−1) with a determination coefficient (R2) of 0.9991. The limit of detection, extraction recovery, and relative recoveries were obtained to be 1.50 ng mL−1, 98.1%, and 90.6–103%, respectively. The intra-day relative standard deviation percentages (n = 5) for different concentrations were in the range of 2.33–3.11%. The proposed method offers merits such as swiftness, high sensitivity, rendering it applicable to detect trace levels of copper (5.19–14.2 ng mL−1 or ng g−1) in water, food, and agricultural soil samples.