| 摘要 |
The purified Group A polysaccharide antigen isolated from N. meningitidis for vaccination against this type of bacterial meningitidis is prepared from an isotonic ratio of aqueous sodium chloride solution freeze-dried at temperatures of from -20 DEG C. to -30 DEG C. This low temperature lyophilization dries the sodium chloride polysaccharide menstrum without loss of molecular weight, i.e., potency. |
