Comparison of Headspace-Single Drop Microextraction and Dispersive Liquid-Liquid Microextraction for Determination of Benzene in Juice Drinks Containing Vitamin C

In this paper, a fast and effective headspace-single drop microextraction (HS-SDME) method was applied for the determination of traces of benzene in juice drinks containing vitamin C. Benzene is produced in drinks as a result of interaction of sodium benzoate (as food preservative) and ascorbic acid (vitamin C). A mixture of n-hexadecane and n-dodecane was used as extractant in the form of organic drop. Other parameters affecting the extraction of benzene, including volume of organic drop, time of extraction, volume, pH and ionic strength of sample solution, were studied and optimized. The obtained dynamic range under optimised conditions was from 2 to 350 mu g L-1 with the limit of detection of 1.49 mu g L-1. The obtained data for HS-SDME of benzene were compared with the data obtained for the determination of benzene with dispersive liquid-liquid microextraction (DLLME). It was observed that though DLLME is simpler and faster, the limit of detection and the repeatability of HS-SDME were better.