ABSTRACT
OBJECTIVE: To assay the anticoagulant activity of leeches by using biological standardization method with the aim to explore the quality control method which can reflect the biological activity. METHODS: Heparin was used as the reference substance, and APTT value was used as the index of anticoagulant activity evaluation. Four species of leeches were determined, including Hirudo nipponia Whitman, Poecilobdella manillensis Lesson, Poecilobdella javanica Wahlberg, and Whitmania pigra Whitman. The determination results were calculated with standard curve and bioassay statistics. RESULTS: The concentration-response curves of APTT of the four species of leeches were similar to that of heparin, and their variation ranges were parallel. CONCLUSION: APTT values can reflect the comprehensive anticoagulant activity of different species of leeches, which may have more clinical significance. Biological standardization is a good supplement to the current quality control methods, also a proper technology for the quality control of TCM.