Effective magnetic nanoadsorbent based on natural carboxymethyl cellulose/polyaniline nanotube/graphene oxide for...

A magnetic nanoadsorbent was prepared via a novel one-pot magnetization method by employing natural carboxymethyl cellulose (CMC), polyaniline (PANI) nanotube, and graphene oxide (GO) for the effective adsorption of aflatoxins B1 (AFB1) and B2 (AFB2) from rice samples. This synthesized adsorbent combines the multifunction of CMC, PANI, and GO and shows improved extraction performance. FT-IR, XRD, FE-SEM, VSM, and TGA analyses were used to investigate the successful synthesis of the nanocomposite. The adsorption mechanism was ascribed to π-π interactions, hydrogen bonding, and hydrophobic interactions. Under optimized conditions, the method achieved extraction recoveries ranging from 78 % to 89 %. Low limits of detection (LODs) and quantification (LOQs) were obtained in the ranges of 0.07 and 0.01 ng g^-1, and 0.20 and 0.04 ng g^-1 for AFB1 and B2, respectively. This method showed an acceptable precision with intra- and inter-day relative standard deviations (RSDs) of less than 15 %. Comparative studies with other adsorbents used in extraction methods such as solid phase extraction (SPE), magnetic dispersive solid phase extraction (MDSPE), and matrix solid-phase dispersion (MSPD) demonstrated that the proposed method outperforms the existing procedures; it is promising in efficient AFs monitoring in rice.