Hydrogen-bonded Organic Frameworks Decorated Polymeric High Internal Phase Emulsions as Adsorbents for Solid-Phase...

Due to lipid-rich and severe matrix interference, the accurate determination of trace estrogens in cosmetics is highly challenging. Although solid-phase extraction (SPE) is widely used to mitigate the matrix interference, conventional adsorbents are often limited to cosmetic matrices. To this end, polymeric high internal phase emulsions modified with a hydrogen-bonded organic framework (polyHIPEs@HOF) were used as an adsorbent for the SPE of five estrogenic compounds. Benefiting from the hypercrosslinked architecture with interconnected macroporosity of polyHIPEs and hydrophilicity of HOF, the synthesized composites were suitable for SPE of estrogen in a cosmetic sample. Under optimized conditions, polyHIPEs@HOF enabled the rapid extraction of five estrogens from complex cosmetic samples, achieving adsorption equilibrium within 4 min, and the extraction recoveries exceeded 78.28%. The adsorption capacities for estrogens ranged from 8.44 to 15.39 mg g^-1, and the adsorption involved multiple interactions (hydrogen bonding, π-π stacking, and hydrophobic effects). Furthermore, the polyHIPEs@HOF composite was able to eliminate the interference of the complex cosmetic matrix, and the extraction efficiency remained stable over 10 consecutive reuse cycles. These results confirm that the polyHIPEs@HOF composite is a highly efficient and reusable adsorbent for the extraction of estrogens in complex sample matrices.