Manual ELISA assays on tPA and PAI-1 automated on Novapath I.S. preliminary report

Tissue plasminogen activator (tPA) and plasminogen activator inhibitor 1 (PAI-1) have been pointed out as markers for deep venal thrombosis, acute myocardial infarction and several thrombotic disorders. This paper reports automation on Novapath I.S. analyzer (BioRad, Segrate Milano) of two manual Elisa procedures on microtritation plates for tPA and PAI-1; Tint Elize tPA and Tint Elize PAI-1 respectively (Biopool Atlanta, Georgia--for Italy Menarini diagnostics, Florence). Automation vs manual procedure allows: 1) higher safety for the operator, 2) better linearity of the standard curve, 3) better analytical precision: 6.8% and 5.3% CV on automation vs 19.8% and 15.7% CV for tPA and PAI-1 respectively, 4) simultaneous assays of tPA and PAI-1, which save time up to 10 hours (6 vs 16 hours), 5) a steady interval between every analytical step, particularly between the interchange of substrate and blocking solution. Accuracy of these procedures must of course be further evaluated.