... Do not interchange reagents from different lots or use test kit beyond expiration date.4. Icteric, lipemic, hemolysed, heat treated ... heparin, respectively) by veinpuncture.Carefully withdraw the blood for testing, or label and store it at 2-8°C for ... the plasma by centrifugation.Carefully withdraw the plasma for testing, or label and store it at 2-8°C ... the result in 10 –20 minutes. PSA Elisa Test Kit