Selective Extraction of Low Molecular Weight Proteins by Mesoporous Silica Particles with Phenyl Modified Internal and Alkyl-diol Modified External Surfaces

Selective extraction of low molecular weight (LMW) proteins and peptides from complex biological samples plays an important role in the discovery of useful biomarkers and signaling molecules. It was demonstrated that the unique pore structure of mesoporous material made it efficient to enrich LMW proteins and peptides from complex matrixes. In this study, a mesoporous material with modified external (alkyl-diol group) and internal (phenyl group) surfaces (alkyl-diol@phenyl-SiO2) was prepared by co-condensation and post-grafting, and its characteristic was evaluated by Fourier transform-infrared spectra (FT-IR) and mass spectrometry (MS). The LMW proteins and peptides enriched by the alkyl-diol@phenyl-SiO2 mesoporous material could be easily eluted by organic solvents, which was compatible with the following detection by MS. This new mesoporous material exhibited good selectivity for the extraction of LMW proteins and peptides (less than 10 kDa) from complex biological samples.

The alkyl diol-phenyl-SiO2 mesoporous material was applied to selectively extract low molecular weight proteins and peptides in plasma. MALDI MS spectra of human plasma (a) and its extracts (b) by alkyl-diol@phenyl-SiO2 were shown in the Figure. The material had good selectivity for the extraction of LMW proteins from biofluids.Figure optionsDownload as PowerPoint slide