Hydrophobic Natural Eutectic Solvents for the Gas Chromatographic Determination of Suspected Allergens in Fragrances by Dispersive Liquid-Liquid Microextraction

Abstract

The fragrance industry plays a key role in the global economy, producing a wide range of personal care and household products. However, some fragrance ingredients have been linked to allergic reactions in sensitive people, and their concentrations are regulated at the European level. For this reason, reliable, rapid, and sustainable analytical methods are needed to rapidly detect and quantify these compounds. Recently, a new class of hydrophobic eutectic solvents (HES) has been introduced; they consist of natural terpenoids or phenolic compounds that can be used as hydrogen bond donors (HBD) and acceptors (HBA), and they are more suitable for GC applications due to their higher volatility. In this study, a dispersive liquid–liquid microextraction (DLLME) approach is proposed for the analysis and quantification of a range of allergens in hydroalcoholic perfumes. The optimized method requires only 50 µL of a natural HES (thymol–eugenol), which is readily dispersed by vortexing in 2 mL of sample. After centrifugation, the HES rich phase is diluted in 400 µL EtOH and directly injected into the GC-FID system. The proposed method has been successfully applied in the analysis and quantification of commercial fragrances, demonstrating good enrichment of target allergens and suitability for aqueous matrices analysis.

Keywords

• natural eutectic solvents
• dispersive liquid–liquid microextraction
• cosmetic allergens
• fragrances
• gas chromatography
• green sample preparation