The thaw-siphon procedure for routine production of cryoprecipitate is described briefly,
and also its extension to a reproducible procedure for production of cryoprecipitates
of intermediate purity. For the latter, the average yield of factor VIII is 60% of
that in the prefrozon plasma and approximately 30% is present in the supernatant plasma.
The product contains 0.53 units of VIII:C per mg of total protein (of which about
70% is clottable). The mean value of the ratio VIII:C/VIII:RAG is about 0.7. The yield
and purity of the product compare favourably with those reported for intermediate
purity factor VIII concentrates produced by large-scale plasma fractionation laboratories.
The procedure offers an alternative pathway to the production of factor VIII concentrate
of intermediate purity and can be operated in any blood bank with a minimum of equipment.
Keywords
F VIII: C - Cryoprecipitation - Thaw-siphon
