Free Prostate Specific Antigen (fPSA) ELISA
The Free Prostate Specific Antigen (fPSA) ELISA is For Research Use Only
Size: 1×96 wells
Sensitivity: 0.05 ng/mL
Dynamic Range: 0.1–15 ng/mL
Incubation Time: 75 minutes
Sample Type: Serum
Sample Size: 50 μL
The principle of the Free Prostate Specific Antigen (fPSA) ELISA Assay enzyme immunoassay test follows a typical one-step capture or ‘sandwich’ type assay. The assay makes use of two highly specific monoclonal antibodies: A monoclonal antibody specific for fPSA is immobilized onto the microplate and another monoclonal antibody specific for a different region of fPSA is conjugated to horse radish peroxidase (HRP). fPSA from the sample and standards are allowed to bind simultaneously to the plate and to the HRP conjugate. The washing and decanting steps remove any unbound HRP conjugate. After the washing step, the enzyme substrate is added. The enzymatic reaction is terminated by addition of the stopping solution. The absorbance is measured on a microtiter plate reader. The intensity of the colour formed by the enzymatic reaction is directly proportional to the concentration of fPSA in the sample. A set of standards is used to plot a standard curve from which the amount of fPSA in patient samples and controls can be directly read.
SPECIMEN COLLECTION AND STORAGE
Approximately 0.2 mL of serum is required per duplicate determination. Collect 4–5 mL of blood into an appropriately labelled tube and allow it to clot. Centrifuge and carefully remove the serum layer. Store at 4°C for up to 24 hours or at -10°C or lower if the analyses are to be done at a later date. Consider all human specimens as possible biohazardous materials and take appropriate precautions when handling.