Automated estimation of factor Xa using the chromogenic substrate S-2222.
A rapid automated method for the estimation of factor Xa was developed using the "Centrifichem' rotary fast analyser and the substrate S-2222. The problem of interference from fibrin was overcome by performing the activation of factor X during centrifugation, so that defibrination and activation were achieved in a single step. A range of factor Xa concentrations was determined on 50 normal plasmas. This assay was correlated with a clotting assay of factor Xa using serial dilutions of normal plasma and plasma from 30 patients receiving warfarin therapy.
D000293:Adolescent; D000328:Adult; D001322:Autoanalysis; D001777:Blood Coagulation; D002498:Centrifugation; D005170:Factor X / Q000096:biosynthesis; D015951:Factor Xa; D005260:Female; D006801:Humans; D008297:Male; D008875:Middle Aged; D009842:Oligopeptides
D009842:Oligopeptides; C015608:benzoyl-Ile-Glu-Gly-Arg-p-nitroanilide; D005170:Factor X; D015951:Factor Xa