Report of a working group for the European Pharmacopoeia. Collaborative assay on human albumin of different origin.

A collaborative assay was conducted by 9 laboratories on 31 samples of human albumin which were in clinical use. It was the object of the study to establish test systems which would differentiate between albumins of venous or placental origin. The properties examined for this purpose were: appearance, total protein, haem, polymers, alkaline phosphatase and blood group substances. Additional tests such as for beta-thromboglobulin and citrate were included; pyrogenicity, however, was excluded because this was under study for all plasma proteins at that time. Results obtained were in satisfactory agreement both between laboratories and between samples. They, therefore, enabled the verification of a number of correlations in the test systems. The evaluation did not allow, however, the differentiation of the samples in relation to their origin. The results were, therefore, regarded as a tool to define the upper limits of acceptance for human albumins corresponding to the quality prescribed by the European Pharmacopoeia.