Prothrombin Time Reagent

Spectrum Diagnostics Recoplastin reagent as prothrombin time (PT)
test, utilize this series of enzymatic events in vitro under controlled
conditions to diagnose deficiencies in the blood coagulation systems
of patients, and to monitor patients on anticoagulant therapy. In the
PT test, a reagent which induces coagulation is added to a sample
of the patient's plasma. All PT reagents contain tissue factor as a
coagulation inducing ingredient. The time it takes for clot formation
to occur in the plasma sample is the prothrombin time or PT value.
Most commercially available PT reagents contain crude tissue factor
extracted from natural sources, e.g., rabbit brain, rabbit brain/lung
mixtures, human placenta or bovine brain. The crude extracts,
because they are natural products, often lack lot to lot uniformity.
For example, rabbit brain thromboplastins show seasonal variability.
Another problem with natural extracts is the presence of contaminants.
For example, human tissue factor may be a source of HIV or other
human viral diseases and many natural-sourced thromboplastins
also contain other extraneous coagulation factors which can
detrimentally affect the PT value.
In an attempt to overcome some of these problems, recombinant
tissue factors have been used to formulate Recoplastin PT reagents.