Optimization of an analytical methodology for the simultaneous determination of different classes of ultraviolet filters in cosmetics by pressurized liquid extraction-gas chromatography tandem mass spectrometry

A methodology based on pressurized liquid extraction (PLE) followed by gas chromatography-tandem mass spectrometry (GC-MS/MS) has been developed for the simultaneous analysis of different classes of UV filters including methoxycinnamates, benzophenones, salicylates, p-aminobenzoic acid derivatives, and others in cosmetic products. The extractions were carried out in 1 mL extraction cells and the amount of sample extracted was only 100 mg. The experimental conditions, including the acetylation of the PLE extracts to improve GC performance, were optimized by means of experimental design tools. The two main factors affecting the PLE procedure such as solvent type and extraction temperature were assessed. The use of a matrix matched approach consisting of the addition of 10 μL of diluted commercial cosmetic oil avoided matrix effects. Good linearity (R2 > 0.9970), quantitative recoveries (>80% for most of compounds, excluding three banned benzophenones) and satisfactory precision (RSD < 10% in most cases) were achieved under the optimal conditions. The validated methodology was successfully applied to the analysis of different types of cosmetic formulations including sunscreens, hair products, nail polish, and lipsticks, amongst others.