In vitro stability of free prostate-specific antigen (PSA) and prostate- specific antigen (PSA) complexed to α1-antichymotrypsin in blood samples
Objectives. To study the in vitro stability of free and complexed forms of prostate specific antigen (PSA) in blood samples in order to establish guidelines for specimen handling, in particular for the clinical utility of the analysis of percentage free PSA. Methods. Blood samples were collected and processed to generate serum, heparin plasma, and EDTA plasma. Three different two-site immunoassays