A magnetic microparticle-based immunoassay for hepatitis C virus NS3 antigen

In order to detect Hepatitis C virus NS3 antigen (HCAg-NS3) in human serum, we developed a magnetic microparticle (MMP) based immunoassay by using biotin-streptavidin amplification, MMP in combination with immunoassay. Results showed that the HCV NS3 monoclonal antibody had a high immobility rate (87.1%) on the surface of MMPs; the assay procedure required smaller volumes of reagents (only 20 mu l of immune magnetic bead); the detection could be completed within 30 min; this method could detect 10 pg/ml HCAg-NS3 (sensitivity: 5.2 pg/ml) and had favorable stability; the mean coefficient of variances (CVs) of intra-assay and inter-assay were 5.35 and 7.15%, respectively. The results of this method were also related to those in HCV RNA detection with a linear correlation coefficient of 0.570 (P < 0.01). These findings demonstrate this assay which has high specificity, sensitivity, precision and stability may be promising in clinical application.