Fibrin
Monomer assay
Specimen requirements:
Fresh whole blood collected in
sodium citrate at a 9:1 ratio of blood to anticoagulant
Principle:
Ethanol gelation test:
The pH of plasma is
adjusted to >7.7 and ethanol is added. The fibrin monomers will form a precipitate.
Protamine sulfate test:
Tested within 2 hours
Dilutions of protamine
sulfate are added to plasma and incubated for 30 minutes. Test is positive if fibrin
strands form (clot).