title: Biofunctionalization of silica microspheres for protein separation.
abstract: Mercapto-silica (SiO2-SH) microspheres were prepared via direct hydrolysis of 3-mercaptopropyltrimethoxysilane (MPS) in a basic aqueous solution. The content of surface thiol group (SH) of SiO2-SH microspheres was measured by Ellman's reagent method and X-ray photoelectron spectroscopy (XPS) and the content of surface thiol group of SiO2-SH microspheres is strongly dependent on the reaction conditions. The thermal stability of SiO2-SH microspheres was evaluated by thermogravimetric (TG) analysis, which tended to reduce with the increase of content of surface thiol groups. SiO2-SH microspheres can be easily modified with reduced glutathione (GSH) to generate SiO2-GSH microspheres for the affinity separation of Glutathione S-transferase (GST). Sodium dodecyl sulfate-polyacrylamide gel electrophoresis (SDS-PAGE) was performed to examine the validity of the separation procedure. The results showed that SiO2-GSH microspheres were efficient in GST affinity separation from mixed proteins.
authors.affiliation: Institute of Immunology, Henan University, Kaifeng 475004, PR China.
authors.forename: Binjie
authors.initials: B
authors.lastname: Li
authors.forename: Xueyan
authors.initials: X
authors.lastname: Zou
authors.forename: Yanbao
authors.initials: Y
authors.lastname: Zhao
authors.forename: Lei
authors.initials: L
authors.lastname: Sun
authors.forename: Shulian
authors.initials: S
authors.lastname: Li
mesh_terms: D004591:Electrophoresis, Polyacrylamide Gel; D005978:Glutathione / Q000737:chemistry; D046529:Microscopy, Electron, Transmission; D008863:Microspheres; D056951:Photoelectron Spectroscopy; D011506:Proteins / Q000302:isolation & purification*; D012822:Silicon Dioxide / Q000737:chemistry*; D017550:Spectroscopy, Fourier Transform Infrared; D013818:Thermogravimetry; D014961:X-Ray Diffraction
chemical_list: D011506:Proteins; D012822:Silicon Dioxide; D005978:Glutathione