目的 探讨凝胶法测定人脐带间充质干细胞培养上清中细菌内毒素的可行性。方法 收集人脐带间充质干细胞培养72 h的上清为供试品。参照《中国药典》2020年版第三部通则1143细菌内毒素检查法中凝胶法的具体要求和步骤对鲎试剂进行灵敏度复核，对供试品进行干扰初筛试验、干扰试验和供试品细菌内毒素的测定。结果 鲎试剂灵敏度测定值为0.125 EU/mL，在0.5λ～2.0λ符合规定，可用于后续试验。供试品1、2、4倍稀释对鲎试剂均无干扰；干扰试验验证2倍稀释供试品对细菌内毒素凝胶法检测无干扰作用；采用凝胶法测定2倍稀释供试品的细菌内毒素含量均≤0.5 EU/mL，判定供试品中细菌内毒素含量合格。结论 凝胶法可用于人脐带间充质干细胞培养上清中细菌内毒素的检测。

Objective To investigate the feasibility of sol-gel method to detect bacterial endotoxin in supernatant of human umbilical cord mesenchymal stem cells (hUC-MSCs). Methods The supernatants of hUC-MSCs cultured for 72 h were collected as the test substance. According to incoterms 1143 on sol-gel method of bacterial endotoxin test (BET) method in Chinese Pharmacopoeia Ver. 2020, sensitivity tests of tachypleus amebocyte lysate (TAL) was studied, then interference initial screening test, interference verification test, and the endotoxin content in samples were determined by sol-gel method. Results The TAL with the sensitivity of 0.125 EU/mL coincided with the regulation in the range of 0.5λ-2.0λ, and could be used in the tests. The samples diluted 1, 2, and 4 times, interference initial screening test weren’t observed the effect of inhibition. The interference verification test with 2 times dilution of samples had no impact on TAL. Sol-gel method was used to determine the endotoxin, and indicated the TAL in samples with 2 times dilution was less than 0.5 EU/mL qualified to regulation. Conclusion It is suitable for bacterial endotoxin in supernatant of hUC-MSCs by sol-gel method.

R286.02

云南省卫生健康委员会内设机构资助项目（2017NS228，2018NS261）；云南省临床病毒学重点实验室项目（202205AG070053）；云南省卫生科技计划项目（L-2019003）；云南省血液疾病临床医学中心开放课题（2020LCZXKF-XY04）