目的    制备牛血清白蛋白（bovine serum albumin，BSA）残留量检测试剂盒的内部参考品，用于考察试剂盒的稳定性。方法   首先对乙型脑炎减毒活疫苗生产过程中的3种工作液（病毒稀释液、病毒浸泡液、细胞上清液）进行BSA残留量检测。然后选择BSA含量适宜的工作液，适当稀释后制成内部参考品。由2名实验人员同时选取3个不同批号的试剂盒，在不同的日期进行3次检测，对内部参考品进行标定，并根据标定结果确定其赋值范围。分别采用方差分析和t检验对不同批号试剂盒和不同实验人员的检测结果进行比较。标定后连续8个月20次使用该参考品考察试剂盒的稳定性。结果   根据BSA残留量检测结果，选择病毒浸泡液，以疫苗冻干保护剂3倍稀释后制成内部参考品。2名实验人员的108次检测均值为33.46 ng/ml，标准差为2.15 ng/ml，变异系数为6.40%。根据标定结果，确定内部参考品的赋值范围为27.01～39.91 ng/ml。不同批号试剂盒检测结果的差异有统计学意义（F=11.497，P<0.01），不同实验人员检测结果的差异无统计学意义（t=0.500，P>0.05）。采用5个批号试剂盒总共对该参考品进行20次检测，BSA残留量均在30.00～36.63 ng/ml范围内，均值为33.14 ng/ml，标准差为1.73 ng/ml，变异系数为5.20% ，不同批号试剂盒检测结果的差异无统计学意义（F=0.997，P>0.05）。结论   制备的BSA残留量检测试剂盒内部参考品可用于试剂盒的稳定性考察。

Objective   To prepare an internal  reference to investigate the stability of   bovine serum albumin (BSA) residue detection kit. Methods   BSA  residues in 3 working liquids, including virus  diluent, virus soaking liquid and cell supernatant, during the production process of  a live attenuated Japanese encephalitis vaccine were detected.  The liquid with appropriate BSA content was diluted by vaccine freeze-drying protective agent to prepare the internal reference. The reference was standardized  3 times at different dates by 2 laboratory workers using 3 batch kits, then the assignment range was determined. The detection results from different batch kits and different workers were compared by ANOVA and t-test, respectively.  In the following 8 months, the internal reference was used 20 times to investigate the stability of the detection kit. Results   According to the BSA detection, virus soaking solution was  chosen and 3-fold diluted by freeze-drying protective agent to prepare the internal reference. The mean value (Mean), standard deviation (SD) and coefficient of variation (CV) of 108 detection values were 33.46 ng/ml, 2.15 ng/ml, and  6.40%, respectively. The assignment range of the reference was determined as 27.01-39.91 ng/ml.There was significant difference among the detection results from different batch kits (F=11.497,  P< 0.01). No significant difference was observed between the detection results from 2 workers (t=0.500, P>0.05). The internal reference was detected 20 times using 5 batch kits, and BSA contents were in the range of 30.00-36.63 ng/ml , with Mean of 33.14 ng/ml, SD of 1.73 ng/ml, CV of 5.20%. There was no significant difference among the results from different batch kits (F=0.997, P>0.05). Conclusion   The internal reference can be used to investigate the stability of BSA residue detection kit.