Preparation method of sheep-derived low-molecular heparin sodium

The invention discloses a preparation method of sheep-derived low-molecular heparin sodium, which comprises the following steps: treating a sheep intestinal mucosa glycosaminoglycan aqueous solution with anion exchange resin; adding a sodium acetate methanol solution in the glycosaminoglycan esterification process for precipitation; carbonate is added in the degradation reaction for degradation; and finally obtaining a sheep-derived low-molecular heparin sodium refined product. According to the method, sheep intestinal mucosa glycosaminoglycan is used as a starting material, the process route is short, the prepared sheep-derived low-molecular heparin sodium is high in yield and good in quality, no waste gas or toxic waste water is discharged in the process, the solvent can be recycled after being recycled, the environmental friendliness is high, the product quality completely meets the European Pharmacopoeia of enoxaparin sodium and the United States Pharmacopoeia standards, and the method is suitable for ind