| abstract |
(57) [Summary]nIncreased fibrinogen yield is obtained by adding a precipitant to plasma having a high platelet concentration, for example, platelet-rich plasma. The precipitant is any of several known, including polyethylene glycol and ammonium sulfate. Platelet-rich plasma is obtained in a preferred embodiment by subjecting the plasma to a "soft spin" centrifugation at about 580G. To separate the anticoagulated whole blood into platelet-rich plasma components and red blood cells, preferably automatic multi-stage tilting and multi-speed centrifuges are used. The proteins, preferably fibrinogen, FXIII and FVIII, in the platelet-rich plasma component are precipitated, and the proteins and platelets are then concentrated by further centrifugation. |