A double antibody sandwich microELISA for measuring human platelet factor 4

With the aim of investigating patients with a higher risk of thrombosis we developed a method for determining platelet factor 4 (PF4) in human plasma. Using the double antibody sandwich ELISA technique we set up a test system that allows the determination of PF4 concentrations in plasma samples from 1 to 100 ng/ml. This method is more sensitive and as specific as commercially available RIA kits, but has the advantage of being cheaper and less time consuming. Furthermore the ELISA does not require radioactive materials. The complete reaction is carried out in microtiter wells, and an ELISA-reader connected to an Apple computer does all the calculations needed for quantitative measurements.