A β-cyclodextrin sorbent based on hierarchical mesoporous silica for the determination of endocrine-disrupting...

In the present work, a method for the determination of parabens and bisphenol A in urine samples has been developed. For this purpose, a novel hierarchical mesoporous silica doped with β-cyclodextrin was developed and used as a sorbent for preconcentration and clean-up step, before analyte determination by liquid chromatography coupled to mass spectrometry detector. Disordered silica materials were also synthesized for comparison purposes. All materials were characterized by electron microscopy, X-ray diffraction, porosimetry, nuclear magnetic resonance, thermogravimetric analysis, elemental CNH analysis, and confocal microscopy, and the attachment of cyclodextrins has been proved as well as their uniform distribution in the resulting material. After the optimization of several protocol parameters, good analytical features were achieved, including recoveries in the range of 96-109% for all analytes, as well as relative standard deviations between 8 and 24%. Also, limits of quantification in the range of 0.003-0.19 µg L^-1 were obtained in all cases. The developed method was applied to the determination of parabens and bisphenol A in real urine samples in comparison with a reference method using C18 cartridges, including the correction with creatinine content. Target analytes were detected in all analysed samples, with being BPA the most detected compound.