| 초록 |
This study will present the effective and self-oriented immobilization of antibodies using multimeric protein Gs. Cysteine-tagged recombinant dimer and trimer of protein G were produced in E. coli BL21 by repeated linking of protein G monomers with a flexible (GGGGS)3 linker. Amino-functionalized silica coated magnetic nanoparticles were prepared and coupled to the protein G multimers, giving the final magnetic immunosensor. The optimal conditions for the reaction between the protein Gs and the particles were a time of 60 min and a concentration of 100 mg/ml, resulting in coupling efficiencies of 77%, 67% and 55% for the monomeric, dimeric and trimeric protein Gs, respectively. Subsequently, anti-hepatitis B surface antigen (HBsAg) was immobilized onto protein G coupled nanoparticles. The lowest detectable concentrations were 500, 250 and 50 ng/ml for the monomeric. dimeric and trimeric protein G coupled nanoparticles, respectively. |
