摘要
A method for the two-step synthesis of magnetic composites with a γ-Fe 2 O 3 core, silica inner layer and numerous gold nanoparticles supported on the surface of the silica (γ-Fe 2 O 3 /SiO 2 /Au) is described. First, thiol-functionalized γ-Fe 2 O 3 /SiO 2 composites and gold colloids are prepared by modifying γ-Fe 2 O 3 /SiO 2 composites with mercaptosilane and reduction of Au 3+ to Au 0 with citrate, respectively. Gold nanoparticles are then assembled on the surface of the thiol-functionalized γ-Fe 2 O 3 /SiO 2 composites to form γ-Fe 2 O 3 /SiO 2 /Au composites. The structure of the composite particles is confirmed by transmission electronic microscopy and powder X-ray diffraction. Immobilization studies with bovine serum albumin (BSA) demonstrate that the γ-Fe 2 O 3 /SiO 2 /Au composites can be used to immobilize BSA, making them useful for biomedical and biological applications.
A method for the two-step synthesis of magnetic composites with a γ-Fe 2 O 3 core, silica inner layer and numerous gold nanoparticles supported on the surface of the silica （γ-Fe 2 O 3 /SiO 2 /Au） is described. First, thiol-functionalized γ-Fe 2 O 3 /SiO 2 composites and gold colloids are prepared by modifying γ-Fe 2 O 3 /SiO 2 composites with mercaptosilane and reduction of Au 3＋ to Au 0 with citrate, respectively. Gold nanoparticles are then assembled on the surface of the thiol-functionalized γ-Fe 2 O 3 /SiO 2 composites to form γ-Fe 2 O 3 /SiO 2 /Au composites. The structure of the composite particles is confirmed by transmission electronic microscopy and powder X-ray diffraction. Immobilization studies with bovine serum albumin （BSA） demonstrate that the γ-Fe 2 O 3 /SiO 2 /Au composites can be used to immobilize BSA, making them useful for biomedical and biological applications.
基金
supported by the Research Program of the Education Department of Shaanxi Province (09JK765)
