Miniaturized Sample Preparation Methods to Simultaneously Determine the Levels of Glycols, Glycol Ethers and Their Acetates in Cosmetics

Abstract

Two environmentally friendly methodologies based on ultrasound-assisted extraction (UAE) and micro-matrix solid-phase dispersion (µMSPD) followed by gas chromatography-mass spectrometry (GC-MS) analysis are proposed for the first time for the simultaneous analysis of 17 glycols, glycol ethers, and their acetates in cosmetics. These sample preparation approaches result in efficient and low-cost extraction while employing small amounts of sample, with a low consumption of reagents and organic solvents. The use of a highly polar column allows for the direct analysis of the obtained extracts by GC-MS without a previous derivatization step, drastically reducing the sample preparation time and residues and thus complying with green analytical chemistry (GAC) principles. Both the UAE and µMSPD methodologies were validated in terms of linearity, accuracy, and precision, providing satisfactory results. LODs were found to be lower than 0.75 µg g−1, allowing the determination of trace levels of the forbidden target compounds. Finally, the validated methodologies were applied to real cosmetics and personal care products, showing suitability, and providing a reliable and useful tool for cosmetics control laboratories.