Development of a multi-preservative method based on solid-phasemicroextraction–gas chromatography–tandem mass spectrometry forcosmetic analysis

摘要

A simple methodology based on solid-phase microextraction (SPME) followed by gas chromatography–tandem mass spectrometry (GC–MS/MS) has been developed for the simultaneous analysis of differ-ent classes of preservatives including benzoates, bronidox, 2-phenoxyethanol, parabens, BHA, BHT andtriclosan in cosmetic products. In situ acetylation and subsequent organic modifier addition have beensuccessfully implemented in the SPME process as an effective extractive strategy for matrix effect com-pensation and chromatographic performance improvement. Main factors affecting SPME procedure suchas fiber coating, sampling mode, extraction temperature and salt addition (NaCl) were evaluated bymeans of a 3 × 2~(3–1) factorial experimental design. The optimal experimental conditions were establishedas follows: direct solid-phase microextraction (SPME) at 40?C and addition of NaCl (20%, w/v), using aDVB/CAR/PDMS fiber coating. Due to the complexity of the studied matrices, method performance wasevaluated in a representative variety of both rinse-off and leave-on samples, demonstrating to have abroad linear range (R~2> 0.9964). In general, quantitative recoveries (>85% in most cases) and satisfactoryprecision (RSD< 13% for most of compounds) were obtained, with limits of detection (LODs) well belowthe maximum authorized concentrations established by the European legislation. One of the most impor-tant achievements of this work was the use of external calibration with cosmetic-matched standards toaccurately quantify the target analytes. The validated methodology was successfully applied to the anal-ysis of different types of cosmetic formulations including body milks, moisturizing creams, deodorants,sunscreen, bath gel, dental cream and make-up products amongst others, demonstrating to be a reliablemulti-preservative methododology for routine control.