Evaluation of the suitability of ionic liquid-based liquid-liquid microextractions for blood protein removal

Publication date: Available online 10 October 2018Source: Journal of Pharmaceutical and Biomedical AnalysisAuthor(s): Marieke De Boeck, Lien Moreels, Wim Dehaen, Jan Tytgat, Eva CuypersAbstractThe analysis of biological samples, such as whole blood, comes with several sample preparation challenges. Biological matrices often contain a variety of endogenous components that can interfere with the determination of xenobiotics. Especially blood plasma proteins (e.g. serum albumin) are known to interfere with electrospray ionization and result in analyte ion suppression. Sample preparation techniques should guarantee adequate removal of these biomolecules. The current study aims to determine to which extent proteins are removed from whole blood samples, using ionic liquid-based dispersive liquid-liquid microextraction (IL-DLLME). A qualitative comparison of the protein presence in extracts of IL-DLLME, solid-phase extraction (SPE) and protein precipitation (PP) was performed, using sodium dodecyl sulfate polyacrylamide gel electrophoresis (SDS-PAGE). Additionally, UV/VIS spectrophotometry was used to determine the protein content of a whole blood sample and IL-DLLME, SPE and PP extracts of the same sample. Finally, a quantitative comparison of matrix effects of benzodiazepines present in both whole blood and water samples. SDS-PAGE results showed that IL-DLLME extracts still contained proteins (i.e. albumin, hemoglobin); however, band intensities were comparable to SPE extracts. Sp...
Source: Journal of Pharmaceutical and Biomedical Analysis - Category: Drugs & Pharmacology Source Type: research