Abstract:

Phthalate esters (PAEs) are a group of serious environmental pollutants that are carcinogenic or tumorigenic to humans. In this work, a green, rapid, and effective analytical method based on supercritical fluid chromatography (SFC) has been proposed for the simultaneous determination of the eight PAE plasticizers in sports beverage samples. They are dimethyl phthalate (DMP), diethyl phthalate (DEP), dipropyl phthalate (DPRP), dibutyl phthalate (DBP), dipentyl phthalate (DPP), benzyl butyl phthalate (BBP), di-2-ethylhexyl phthalate (DEHP), and di-n-octyl phthalate (DNOP). Liquid phase extraction (LPE) was employed to extract the PAE plasticizers before testing using SFC with ultraviolet (UV) detection. SFC parameters, including stationary phase screening, modifier composition and volume percentage, column temperature, flow rate, and backpressure, were optimized. Under the optimum conditions, all the eight PAE plasticizers could be determined simultaneously by SFC within 6 min at 225 nm. The optimized eluent was supercritical CO₂ with 3% (v/v) methanol. The performance of the developed method was also evaluated. The eight PAE plasticizers exhibited satisfactory linearities with correlation coefficients (r) of 0.9991-0.9997 in the range of 0.05-25 mg/L. The limits of detection ranged from 7.5 to 15 μg/L (S/N=3, n=3). Recoveries of all the PAE plasticizers for the spiked samples ranged from 91.7%-100.2% with relative standard deviations of no more than 6.5% (n=3). This method is green, time-saving, simple, selective, robust, and convenient for the analysis of the eight PAE plasticizers in real sports beverage samples.

Key words: liquid phase extraction(LPE), phthalate esters(PAEs), plasticizer, sports beverages, supercritical fluid chromatography(SFC)