Purification of canine albumin by heat denaturation in a plasma bag.

OBJECTIVE: To design and evaluate a method to purify canine albumin from fresh frozen plasma (FFP) or stored plasma (SP) in a manner that could be applied clinically.

DESIGN: In vitro experimental study.

SETTING: FDA licensed Blood Bank Laboratory and University biochemistry laboratory.

ANIMALS: None.

INTERVENTIONS: Using equipment that is typically found in veterinary blood banks, plasma bags were thawed, injected with the heat stabilizing agent, sodium caprylate, and then heated and acidified to denature all but albumin proteins. Albumin-rich supernatant was removed, the pH was neutralized, and then pasteurized and refrigerated. Albumin and total plasma protein concentrations were measured and the product was cultured for bacteria at 0, 7, 14, 30, and 60 days post-processing.

MEASUREMENTS AND MAIN RESULTS: Seventeen bags of plasma were analyzed for purity, yield, and sterility of the finished albumin product. Bags were divided into categories based on the age of the frozen plasma. Mean yield of albumin for all bags was 77.3% and mean purity was 91.2%. There was no difference between old stored plasma, new stored plasma, and FFP with regard to yield (P = 0.31) or purity (P = 0.24) based on one-way analysis of variances. Overall 1 of 17 bags of plasma (5.9%) tested positive for bacterial contamination on day 60 after processing.

CONCLUSIONS: Sodium caprylate is able to stabilize canine albumin enabling it to withstand heating that denatures other plasma proteins. The resulting albumin product is of sufficient quality to potentially be used therapeutically as a colloidal resuscitative fluid. Further study is needed into its safety and effect in dogs.