Platelet poor plasma solutions

The entire procedure is performed in plastic (polystyrene) tubes and carried out at room temperature. Freshly collected venous blood is anticoagulated with hirudin (1 volume + 9 volumes of animal blood) or ACD solution (1 volume + 9 volumes of human blood) and centrifuged at 170 x g for 15 min to obtain platelet-rich plasma (PRP). The PRP-supematant is carefully removed, and the rest is further centrifuged at 1500 x g for 10 min to obtain platelet-poor plasma (PPP). PRP is diluted with PPP to a platelet count of 3 x 108/ml before use in the aggregation assays. To obtain washed platelets (WP), 8.5 volumes of human blood are collected into 1.5 volumes of ACD and centrifuged as for PRP. PRP is acidified to a pH of 6.5... 

Sodium heparin (Wyeth Lab, Philadelphia, Pennsylvania) was added from a stock solution individually to the fresh platelet-poor plasma samples Just prior to testing. This heparin is derived from porcine intestinal mucosa. 

The polymer suspension (in 0.15 M NaCl in 0.01 M Tris-HCl, pH 7.5) was mixed (v/v) in a polystyrene tube with either a solution of purified AT or fresh platelet poor plasma (PPP) diluted (v/v) with a solution of purified AT. After 15 min. at room temperature,. the mixture was centrifuged and the AT concentration was measured in the supernatant. The adsorption on the polymer surface was calculated by difference between a control performed with buffer instead of polymer suspension and the protein concentration found in the supernatant. 

Use fresh bovine blood collected in an anticoagulant solution (e.g., sodium citrate solution). Discard any hemolyzed blood. Centrifuge at 1500-1800 g at 15-20°C to obtain a supernatant plasma poor in platelets. 

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