A novel cloud point extraction based on fatty acid deep eutectic solvent combined with high-performance liquid chromatography for determination of ultraviolet absorbent in food packaging bags

A fatty acid deep eutectic solvent (DES) based cloud point extraction (DES-CPE) coupled with high-performance liquid chromatography (HPLC) to determine ultraviolet absorbent (UV) in food packaging bags was presented. In this DES-CPE method, DESs prepared from medium-chain saturated fatty acids (C 8 -C 12 ) and menthol are pH-dependent phase, and acid-base reactions can be carried out solely by adjusting the pH of the solution. The reaction conditions and extraction conditions, such as pH value, speed and time of vortex, selection and dosage of the extraction solvent, reaction time and temperature, effects of salt addition and centrifugation time were investigated in detail. Under optimal condition, the proposed method showed good linear range from 1 to 100μgmL −1 , with good assuming regression coefficients ( R 2 ) ≥ 0.997. The limit of detection (LODs), the quantitation (LOQs), the repeatability (RSDs%) were in the range of 0.05–0.17 μgmL −1 , 0.18–0.52 μgmL −1 , 0.93–2.65%, respectively. The enrichment factor was 10 and the recoveries of three Ultraviolet absorbents were between 82.2% and 103.4%.