Supramolecular solvent-based microextraction probe for fast detection of bisphenols by ambient mass spectrometry

In this study, we investigated for the first time the suitability of supramolecular solvent (SUPRAS)-based microextraction probe for the development of generic and fast sample treatment prior to qualitative analysis by ambient mass spectrometry (AMS) based on ASAP (atmospheric solids analysis probe). SUPRAS are nanostructured liquids formed by the self-assembly of amphiphilic aggregates with multiple binding sites and microenvironments of different polarity for the efficient extraction of multiple compounds. Different types of SUPRAS were evaluated as a simple and single step sample treatment for ASAP. The method was applied to the screening of bisphenol A and structural analogues in thermal paper. Optimal results were achieved with SUPRAS synthesized with 1-decanol in mixtures of ethanol:water. SUPRAS (1.1-2 μL) were loaded onto glass probes and placed in contact with samples for 10 s before ASAP analysis. AMS signal peaks (width: 0.2-0.5 min) were easily integrated and normalized with internal standards (RSD: 2-25%). The method was applied to 62 samples of thermal paper. BPA and BPS were the most widely used, this highlighting the progressive industrial replacement of BPA by BPS.