Application of thermal ultrasound‐assisted liquid–liquid micro‐extraction coupled with HPLC‐UV for rapid determination of synthetic phenolic antioxidants in edible oils

Abstract

AbstractA simple, fast, and reliable liquid–liquid micro‐extraction (LLME) method assisted by thermal ultrasound approach was developed for simultaneous determination of synthetic phenolic antioxidants (SPAs) in edible oils by high‐performance liquid chromatography equipped with ultraviolet detector (HPLC‐UV). The synthetic antioxidants were propyl gallate (PG), butylated hydroxyanisole (BHA), tert‐butylhydroquinone (TBHQ), and butylated hydroxyltoluene (BHT). The best extraction conditions were observed were methanol/acetonitrile (1:1, v/v) as the solvent, ultrasound at 4 min, and a temperature of 40°C. The linearity of the calibration curves for the optimum conditions were R2 > 0.989 for all of the SPAs in a range from 1–200 μg ml−1. Relative standard deviation (RSD %) for five analysis was in range of 2.83% to 4.21%. Limit of detection (LOD) and limit of quantification (LOQ) were obtained in range of 0.012–0.06 and 0.04–0.2 μg g−1, respectively. With regard to recovery, a range of 91%–116% was calculated for the spiked edible oils.