目的 建立首批HPLC含量测定用缩宫素国家标准品。方法 第3批缩宫素国家标准品采用冻干制备。使用核磁共振和HPLC法对缩宫素进行结构确证；采用HPLC法测定待标品的质量分数，并测定待标品水分及氨基酸比值；以缩宫素USP对照品为标准，采用HPLC外标法和大鼠子宫法分别测定待标品的生物效价。结果 经核磁共振和HPLC法确证缩宫素的结构；待标品水分含量为4.8%，各氨基酸比值均在限度范围内，经HPLC检测质量分数为99.69%；待标品经HPLC法测定每支含量为274 IU，经大鼠子宫法测定每支含量为275 IU。结论 建立的待标品可作为第3批缩宫素国家标准品，供缩宫素效价测定及鉴别使用。

Objective To establish the first batch of national standard of oxytocin for high performance liquid chromatography (HPLC). Methods This batch of standard is prepared by freeze-drying. The structure of oxytocin was confirmed by NMR and HPLC. HPLC was used to determine the purity of the standard, moreover the water and amino acid ratio of the standard were determinated. The biological potency of oxytocin was determined by HPLC external standard method and rat uterus method against the oxytocin USP reference standard. Results The structure of oxytocin was confirmed by NMR and HPLC. The water content of the standard sample was 4.8%, the ratio of each amino acid was within the limit, and the mass fraction is 99.69% by HPLC. The content of oxytocin national standard was 274 IU per ampoule by HPLC and 275 IU per ampoule by rat uterus method. Conclusion This batch of standard substance can be used as the first batch of oxytocin national standard for HPLC content determination for oxytocin potency determination and HPLC identification.

R921.2