An Ion-pair Dispersive Liquid-Liquid Microextraction for Simultaneous Determination of Synthetic Dyes in Ice Cream Samples by HPLC

An efficient, sensitive and fast method was developed based on an ultrasound-assisted extraction followed by an ion-pair dispersive liquid-liquid microextraction (USAE-IP-DLLME) for the simultaneous determination of five commonly used synthetic sulfonate dyes (tartarazine, quinoline yellow, sunset yellow, azorubine, and brilliant blue) in ice cream samples using high performance liquid chromatography. First, important parameters on USAE and samples clean-up were investigated and optimized. Then, some effective parameters on DLLME were studied and optimized. Under the optimum conditions, good linearity (0.5–1000 µg L-1, > r2=0.99) were obtained for the dyes. Limits of detection and limits of quantization were in the range of 0.01–0.05 µg L-1 and 0.03–0.15 µg L-1, respectively. The recoveries of the five synthetic colorants ranged from 90.3 to 109.7%. Intra (1.4–6.4%) and inter-day precision (3.9–9.7%) expressed as relative standard deviation (RSD) at 10 and 100 µg L-1 levels less than 10% were also achieved. Finally, this method has been applied successfully in the determination of the colorants in the ice cream samples.