Preparation And Investigation On Performance Of Temperature-responsive Chromatographic Materials Containing Characteristic Groups

In the separation and analysis of proteomics,chromatographic media with special selectivity play a key role in the pretreatment of protein samples.But these chromatographic materials usually need to change the mobile phase to achieve capture and release of the target molecule when they are used to remove high abundance proteins or enrich low abundance proteins,sometimes even with high concentration of salt,organic solvents and extreme pH,it is not conducive to the analysis of biological samples.Temperature-sensitive chromatography using pure water as the mobile phase,capture and release of the target molecule can be achieved only by changing the temperature,so it is very suitable for the analysis of biological sample.The target molecules can be specifically captured by ligands which are introduced into the temperature-sensitive chromatographic materials,then changing the temperature brought the release of target molecules,so the research of temperature-sensitive specific functional chromatography materials is a very meaningful work.In this research,three kinds of chromatographic materials with high selectivity and high release ability were prepared by using the temperature-sensitive properties of poly(N-isopropylacrylamide)and the choice of the ligands of diethylaminoethyl methacrylate(DEAEMA),acrylic acid(AAc)and 4-vinylbenzeneboronic acid(VPBA),and these three chromatographic materials can achieve the capture and release of the target molecules only by temperature control.Finally,three kinds of chromatography materials were used in the pretreatment of mice serum,which resulted the identifiable proteins in mice serum increased.The temperature-sensitive chromatographic materials which conclude alkaline,acid and boric acid groups were prepared by SI-RAFT.The results of IR and X-ray photoelectron spectroscopy showed that the polymer were grafted onto the surface of the silica gel.The graft ratio was measured by thermogravimetric analysis(TGA),which were respectively 14.16%,14.45% and 10.25%.The results of differential scanning calorimetry(DSC)and chromatographic separation of steroids indicated that all of the three grafted silica gels had a very good temperature-sensitive properties.The capture and rapid release of acidic protein(BSA)was achieved by temperature control by Poly(NIPAAm-co-DEAEMA-co-tBAAm)grafted silica gel.The capture and rapid release of basic protein(protamine)was achieved by temperature control by Poly(NIPAAm-co-AAc-co-tBAAm)grafted silica gel.The capture and rapid release of adenosine and glycoprotein(horseradish peroxidase)were achieved by temperature control by Poly(NIPAAm-co-DMAEMA-co-VPBA)grafted silica gel in Hepes buffer at pH=7.Finally,three kinds of polymer grafted silica gel were used in the pretreatment of mice serum,which resulted the identifiable proteins in mice serum increased.The experimental results show that this type of temperature-sensitive chromatography material are expected to be applied to removal of high abundance proteins and enrichment of low abundance proteins in biological samples,which are helpful for the analysis and identification of proteins in biological samples.