Dispersive solid phase extraction of Irganox 1010, Irgafos 168, and Irganox 1076 from milk samples using carbon derived metal-organic framework

A dispersive solid-phase extraction method has been developed for the extraction of Irganox 1010, Irgafos 168, and Irganox 1076 from milk samples using carbon-derived MIL-88(Fe) as an efficient sorbent. To achieve this, 5 mL of milk sample was mixed with 100 mg trichloroacetic acid under vortexing for 3 min. After deprotonating of the sample, the analytes were extracted using 10 mg of carbon-derived MIL-88(Fe). The extraction procedure was accelerated by vortexing (for an addition 3 min). After centrifugation, the adsorbed analytes onto the sorbent were eluted with 125 µL of ChCl: 1,4-butanediol deep eutectic solvent and then analyzed using HPLC-DAD. The influences of different factors affecting the extraction efficiency of the studied antioxidants were evaluated. Under the optimized conditions, the proposed method demonstrated low limits of detection (0.19–0.63 ng mL⁻¹) and quantification (0.63–1.1 ng mL⁻¹), as well as acceptable extraction recoveries above 73 % for migration compounds. Ultimately, this approach was competently applied to evaluate the presence of studied additives in twenty-five milk samples packaged in polyethylene. Notable features of this procedure include minimal usage of sorbent, absence of toxic organic solvent, and negligible matrix effect. Subsequently, the validated analytical method was applied to several cow milk samples, revealing contamination in some of the investigated samples. The effect of storage temperature and time was also investigated.