Fabrication of Three-Dimensional Composite for Fabric-Phase Sorptive Extraction of Aflatoxin M1 From Milk-Based Sport and Bodybuilding Supplements Followed by HPLC With Fluorescence Detection

This study presents the first fabric-phase sorptive extraction (FPSE) approach based on three-dimensional carbonized bio-aerogel/ZnO composite for separation and preconcentration of aflatoxin M1 (AFLM1) from milk-based sport and bodybuilding supplements. The developed extraction method was combined with high-performance liquid chromatography with fluorescence detection (HPLC-FL). The synthesized composite was anchored to a cotton substrate and placed at the end of a burette to be used as a sorbent. By passing the sample solution through the fabric-phase sorbent with the appropriate flow rate, the analytes were trapped by the sorbent. After that, a suitable organic elution solvent was passed through the sorbent at a constant flow rate to elute the analytes. After collecting the elution solvent and evaporating it, the residue was dissolved in the mobile phase and injected into HPLC-FL. Under optimized conditions, the limit of detection (LOD) and limit of quantification (LOQ) for the proposed procedure were 0.003 and 0.010 µg kg⁻¹, respectively. The linear range of the calibration curve was in the range of 0.010–80 µg kg⁻¹ with a correlation coefficient of 0.995. The method's precision was evaluated through intra- and interday relative standard deviations (RSDs) by analyzing seven replicates of target samples containing 10.0 µg kg⁻¹ AFLM1. Results showed intraday precision of 2.1% and interday precision of 4.8%. It was successfully applied to real sport and bodybuilding supplements, showing no significant matrix interference.