Magnetic chitosan/ZIF-L/KCDs granular-leaf hybrid nanocomposite for magnetic dispersive µsolid phase extraction of mycotoxins from ziziphus jujuba, nuts and grains

Abstract

In this study, a novel magnetic chitosan/zeolitic imidazolate frameworks-L/kiwi peel-derived carbon dots (MCS/ZIF-L/KCDs) granular-leaf hybrid nanocomposite was synthesized and used for magnetic dispersive & micro;solid-phase extraction (MD-& micro;SPE) of aflatoxins B1, B2, G1, and G2, and the extracts were analyzed by high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The sorbent was characterized using Fourier-transform infrared spectroscopy, X-ray diffraction, scanning electron microscopy, and energy-dispersive X-ray spectroscopy. The influential parameters were optimized, and under optimum conditions, the developed method showed excellent analytical performance with limits of detection (LOD) of 0.002-0.003 & micro;g kg-1, limits of quantification (LOQ) of 0.007-0.009 & micro;g kg-1, and linear dynamic ranges (LDR) of 0.01-750 and 0.01-1000 & micro;g kg-1, depending on the analyte and matrix. The relative recoveries () of 91.0-99.4, and the intra-day (n = 6) and inter-day (5 days, n = 3) precisions at <= 3.5 and <= 3.0, were acquired, respectively, which confirmed satisfactory capability, reproducibility, and repeatability. The proposed method presented good compliance with green analytical chemistry rules.