OPTIMUM CONDITIONS OF RECEIVING EXTRACT OF THROMBOPLASTIN FROM VARIOUS SOURCES OF BIOLOGICAL RAW MATERIALS
Objective. Definition of the optimum conditions for receiving the extract of thromboplastin using different sources of biological raw material (human placenta, rabbit's brain, human cadaver's brain) for making diagnostic reagents based on the tissue thromboplastin taking into account the WHO requirements to quality of diagnostic reagents (activity 11—13 seconds, international sensitivity index (ISI) 1.0—1.2) was the purpose of the study. Materials and methods. Samples of diagnostic reagents received from different sources of biological material (human placenta, rabbit's brain, human cadaver's brain); 40 samples of plasma of the patients having administered indirect anticoagulants in hypocoagulative doses for a long time; 20 samples of regular donors' plasma having no hemostasis disorders; were used as the test material. Coagulations methods were applied. Results. Conditions of receiving the extract of thromboplastin: EDTA extraction of 1.1mM, temperature of 42°C and 46°C - allow receiving active and highly sensitive diagnostic reagents from the human cadaver's brain (activity 13.9±0.1 seconds, IS11.13±0.2) and from the rabbit's brain (activity 14.3±0.1 seconds, IS11.18±02). At the pH target value 6.4±0.02 of the extracting solution a diagnostic reagent of thromboplastin from the human placenta (activity 11.8±0.2 seconds) was received. Addition of Mn <sup>2</sup>* ions in concentration 0.017 as a part of reagents of thromboplastin (from different sources of biological material) was shown to promote achievement of the specified coagulation activity. Conclusion. The established conditions of the fabric thromboplastin receiving are optimum for making diagnostic reagents on its basis their characteristics being in accordance with the WHO requirements to quality of diagnostic reagents.