定量鲎试验法检测细菌内毒素的几种干扰因子

基因工程蛋白类药物生产中常用的2-巯基乙醇（2－ME）、二硫疏糖醇（DTT）和还原型谷胱甘肽（GSH）对鲎试验显色反应有干扰作用。通过外加已知含量的内毒素溶液至不同浓度的2－ME、DTT和GSH，并与相同内毒素含量的样品比较，结果表明，5．0mmol／L2－ME，DTT和GSH均呈强烈抑制作用，抑制显色达80％、78％、70％，当稀释到5．0μmol／L时，抑制作用近乎消除。高温处理内毒素样品会导致内毒素效价急剧损失，运用加热法来消除干扰作用是不可取的。生理盐水中的NaCl对显色反应有干扰，关键在于稀释样品和标准品须用相同的无热原水或无热原生理盐水。

Interference Factors to Determination of Bacteria Endotoxin Using Quantitative LAL

It was found that the 2-ME, DTT and GSH that was usually used in the production of gene-engineering protein medicine have interference to the color reaction of quantitative LAL. Adding certain concentration of endotoxin to different concentration of 2-ME, DTT and GSH, comparison the OD545nm of treatment with the controls, there exists strongly inhibition to LAL color reaction for 5. 0 mmol/L 2-ME, DTT and GSH, the inhibition rate is 80%, 78%, 70% separatively. But when diluting to 5. 0μmol/ L, the inhibition almost disappeared. Treating the endotoxin with high temperature (75 ℃ and 100℃ ) results in decreasing the potency of endotoxin rapidly, so it is not recommended for using high temperature to eliminate the interference to LAL. Also, the NaCl in physiological saline has interference to LAL color reaction, the same pyrogen-free water or pyrogenfree NS must be used to dilute both the sample and standard endotoxin.