Chemiluminescence Immunoassay for Free Prostate-Specific Antigen

A sandwich chemiluminescence immunoassay (CLIA) for serum free prostate-specific antigen (F-PSA) was developed. One antibody against total PSA was coated on the micro-plate, the other antibody against F-PSA was labeled with horseradish peroxidase. The detection limit is established as 0.01 ng/mL (n＝10, mean of zero standard+2SD) and the intra- and inter-assay coefficients of variation (CV) is in the range of 3.8%-5.4% and 10.8%-17.7%, respectively. Compared with Monobind F-PSA CLIA kits, the correlative equation is y＝0.72x-0.22, and r＝0.90. The standard range for the method is 0.2-10 ng/mL, and it presents good linearity.