Abstract: Stability of Defibrase^® in various pH buffer solutions was investigated. Enzyme-linked immuno-sorbent assay (ELISA) and coagulating time method were used to assess antigenic stability and coagulating stability, respectively. The change of antigenic activities and coagulating activities of Defibrase^® in the same buffer solutions (pH 6, 7 and 8, with the exception of pH 3.6) showed similar tendency to decline with the time. Concentrated Defibrase^® was relatively stable at neutral pH 6~7, more than 95% of its initial activities (100 BU·mL^-1) was kept after a 10-day storage at 40 °C, whereas in pH 3.6 and pH 9 buffer solutions, diluted Defibrase^® was very labile. Addition of Triton X-100 or bovine serum albumin could effectively prevent loss of Defibrase^® by minimizing adsorption of Defibrase^® to plastic surface (P<0.005). Concentration of Defibrase^® could also affect its stability in aqueous solutions.

Key words: Stability, Defibrase, ELISA