title: Stability of total and free prostate specific antigen in serum submitted to intermittent cold storage conditions.
abstract: The goal of this study was to determine the stability of Total Prostrate Specific antigen (PSA-T) and Free Prostrate Specific Antigen (PSA-F) in archival serum stored at 4°C and -20°C and subjected to temperature shift due to interruption in power supply. Our study showed that PSA-T was stable up to 285 days and PSA-F was stable for 158 days under these conditions. Since power supply interruption is an unavoidable problem in developing nations, our study has implication on the validity of measurement of PSA-T and PSA-F in serum that was not properly stored due to emergency situations and for certain types of retrospective studies.
authors.affiliation: Laboratory of Radioimmunoassay, Lebanese Atomic Energy Commission (LAEC), National Council for Scientific Research (NCSR), Airport Avenue, B.P. 11-8281, Beirut, Lebanon  ; Rafik Hariri Campus, Lebanese University, College of Science, Biochemistry department, Hadath, Lebanon  ; Laboratory of Radioimmunoassay, Lebanese Atomic Energy Commission, NCSR, Airport Avenue, B.P. 11-8281, Beirut, Lebanon.
authors.forename: Asmahan A
authors.initials: AA
authors.lastname: El Ezzi
authors.forename: Mohammed A
authors.initials: MA
authors.lastname: El-Saidi
keywords: Immunoradiometric Assay; Interrupted power supply; PSA Free; PSA Total; Prostate SpecificAntigen; Stability