A novel fenchone-based natural deep eutectic solvent for dispersive liquid-liquid microextraction of bisphenol A and bisphenol F from plastic baby products: Synthesis, characterization, method development, and greenness assessment

The application of green analytical chemistry (GAC) principles in method development is receiving growing attention, with an emphasis on using sustainable solvents and decreasing waste production. Consequently, researchers and professionals worldwide are increasingly focused on developing safer and more sustainable alternatives to conventional methods. In the present work, a novel natural deep eutectic solvent (NADES), composed of fenchone and octanoic acid, was synthesized and applied for the first time as a green extractant in dispersive liquid-liquid microextraction (DLLME). This represents a new class of NADES based on monoterpenoid components, expanding the scope of bio-derived solvents in analytical sample preparation The newly prepared NADES (in a 1:1 M ratio) was employed to extract bisphenol A and bisphenol F from commercially available plastic baby products, including toys, pacifiers, and baby bottles. The analytes were quantified using ultra-high performance liquid chromatography coupled with tandem mass spectrometry (UHPLC-MS/MS). Following optimization of the extraction and determination conditions, the method was validated and demonstrated excellent linearity with (r² ≥ 0.9994), recovery rates between 92.5 % and 98.9 %, and limits of detection ranging from 0.004 to 0.01 μg L⁻¹. The greenness profile of the method was evaluated using six assessment tools, providing a comprehensive assessment of its environmental sustainability. A comparison showed that the proposed method outperformed other published methods in terms of sustainability. To the best of our knowledge, this is the first report of a fenchone-based NADES applied to DLLME, marking a significant contribution to the development of green and efficient sample preparation techniques for plastic-associated contaminants.