Silica sol-gel amperometric immunosensor for Schistosoma japonicum antibody assay.
An amperometric immunosensor was constructed by dispersing graphite, schistosoma-japonicum antigen (SjAg) and silica sol-gel at low temperature. The performance characteristics of the prepared immunosensor were examined in the buffered solution of o-aminophenol (o-AP) used as a substrate. It exhibited excellent physical and electrochemical stability with a renewable external surface. A competitive binding assay was employed to determine schistosoma-japonicum antibody (SjAb) with the aid of horseradish peroxidase labeled SjAb (HRP-SjAb). The experimental parameters for SjAb assay were optimized, including the amount of labeled SjAb in incubation solution, incubation time, temperature and the pH of solution. The use of o-AP substrate and amperometric detection at -250 mV (vs. SCE) results in a determination limit of 0.32 microg/ml and a linear range extending up to 0.18 microg/ml. The results of SjAb assay in serum samples demonstrate the feasibility of using the proposed immunosensor for clinical analysis.
Zhong
Tong-Sheng
TS
Department of Chemistry and Environmental Engineering, Hunan City College, Yiyang 413049, P R China.
Liu
Guodong
G
D000818:Animals; D000909:Antibodies, Helminth / Q000032:analysis*; D001667:Binding, Competitive; D006735:Horseradish Peroxidase / Q000737:chemistry; D007120:Immunochemistry; D007202:Indicators and Reagents; D012549:Schistosoma japonicum / Q000276:immunology*; D058428:Silica Gel; D012822:Silicon Dioxide
D000909:Antibodies, Helminth; D007202:Indicators and Reagents; D058428:Silica Gel; D012822:Silicon Dioxide; D006735:Horseradish Peroxidase