| 摘要 |
PROBLEM TO BE SOLVED: To produce the subject homogeneous compound stable in high thrombin activity by converting a heparin into a low-molecular weight one in the presence of a metallic salt under specific conditions by using a specified amount of a peroxide. SOLUTION: A heparin is converted into a low-molecular weight one in the presence of a bivalent metallic salt (e.g. a salt such as copper acetate or copper sulfate) by using a peroxide (e.g. hydrogen peroxide) in a weight X based on the weight Z of the heparin and determined by the formula X=Y/100×Z×W [Y is the content % of a sulfate group-substitute uronic acid in the heparin; W is 1-(1/25)] at 60-80 deg.C for 3-8 hr. Thereby, the low-molecular heparin having a 1.5-3.0 activity ratio of the anti-Xa factor activity/antithrombin activity is produced. The reaction is preferably carried out in an aqueous solution at a heparin concentration within the range of 1-10 wt./vol.%. An adequate amount of ascorbic acid or the like, as necessary, may be added to the reactional solution. The reaction is preferably conducted while keeping the pH thereof at 7.5-7.8.
|
