A method is described in which thrombin activity in clotting plasma can be
monitored through the continuous measurement of the fluorescent split-produ
ct of the substrate Z-Gly-Gly-Arg-AMC. The signal is not impaired by turbid
ity; therefore proper measurement is not disturbed by the occurrence of a c
lot or the presence of platelets and direct measurement in platelet rich pl
asma is possible.