氯霉素氧化锌乳膏微生物限度检查方法验证

目的 建立氯霉素氧化锌乳膏的微生物限度检验方法。方法 按照《中国药典》2020年版四部通则1105、1106，分别采用常规法、增加稀释液、增加培养基体积、增加稀释液-增加培养基体积联合、薄膜过滤法进行方法适用性试验。结果 氯霉素氧化锌乳膏对金黄色葡萄球菌和枯草芽孢杆菌抑制作用较强，需要用薄膜过滤法才能使回收率在0.5～2；控制菌适用性试验中，增加培养基体积可消除样品对金黄色葡萄球菌的抑制作用。结论 需氧菌总数测定采用薄膜过滤法；霉菌和酵母菌总数测定采用常规法；金黄色葡萄球菌检查采用增加培养基体积法；铜绿假单胞菌检查采用常规法。

Verification of microbial limit test method for chloramphenicol zinc oxide cream

Objective To establish a microbial limit test method for chloramphenicol zinc oxide cream.Methods According to thefour general rules 1105 and 1106 of Chinese Pharmacopoeia, Edition 2020, the applicability test of the method was carried out by rou-tine method and such methods as increasing diluent, increasing medium volume, combination of increasing diluent and medium vol-ume, and membrane filtration method.Results Since chloramphenicol zinc oxide cream had a strong inhibitory effect on staphylococ. cus aureus and bacillus subtilis, the membrane filtration method was required to make the recovery rate between 0.5 and 2. Moreover, in-creasing the medium volume could eliminate the inhibitory effect of sample on staphylococcus aureus in the applicability test of control bacteria.Conclusion The total number of aerobic bacteria is tested by membrane filtration method; the total number of molds andyeasts is tested by routine method; staphylococcus aureus is tested by the method for increasing medium volume; pseudomonas aerugino. sa is tested by routine method.