2019—2020年度食品中副溶血弧菌能力验证样品的研制及其应用

Preparation of quality control samples of Vibrio parahemolyticus and their application in the proficiency test in 2019—2020

目的 制备食品中副溶血弧菌检验能力验证样品,并应用于2019—2020年度实验室能力验证考核。方法 将5种背景菌株和副溶血弧菌通过生化、基质辅助激光解吸电离飞行时间质谱鉴定确认菌株种属。采用冷冻干燥技术制备阳性样品和阴性样品,阴性样品仅含有背景菌株,阳性样品在背景菌的基础上添加有副溶血弧菌。随机抽取20份样品进行均匀性检验,将样品存放于-20℃、4℃进行保藏稳定性检验,将样品存放于25℃、37℃进行运输稳定性检验。向参加考核的实验室发放样品并提供作业指导书,回收各实验室结果进行统计。结果 菌株种属确认与预期结果一致,阴性样品和阳性样品的均匀性和稳定性均满足要求。2019年和2020年考核结果满意率分别为87.5%和90%。结论 本研究制备的样品满足食品中副溶血弧菌能力验证项目的要求,通过组织能力验证考核可以反映出我国实验室之间的差异,有助于进一步提高实验室检验水平。

Objective To prepare proficiency testing samples of Vibrio parahemolyticus(V. parahemolyticus)and apply to laboratory test.Methods The five background strains and V. parahemolyticus were identified by biochemical reaction and matrix-assisted laser desorption ionization time of flight mass spectrometry(MALDI-TOF MS). The V. parahemolyticus positive samples and negative samples were prepared by freeze-drying. The negative samples contained background bacteria only and the V. parahemolyticus were added in positive samples with background strains. Twenty samples were selected randomly for uniformity test. The samples were stored respectively at-20 ℃ and 4 ℃ to evaluate the storage stability,meanwhile the transport stability were evaluated by storing samples at 25 ℃ and 37 ℃ for 7 d. Samples were distributed to laboratories participating in the proficiency test with operation instruction,and the feedback results from laboratories were analyzed.Results The results of all the related strains were consistent with the expectations. Both of the positive samples and negative samples could meet the requirements of the uniformity and stabilit. The satisfaction rates of assessment results were 87. 5% and 90% in 2019 and 2020 respectively.Conclusion The V. parahemolyticus samples could meet the requirements of the proficiency test. By organization proficiency test,the difference of laboratories can be discovered which is helpful to further improve the laboratory test capacity.