奶粉中金黄色葡萄球菌标准样品的均匀性和稳定性研究  

Homogeneity and Stability Study on Standard Reference Materials of Staphylococcus aureus in Milk Powder

作　　者：李妍[1] 罗超 李兰英[1] 颜娟[2] 范一灵[3] 杨燕[3] 刘刚[1] LI Yan;LUO Chao;LI Lan-ying;YAN Juan;FAN Yi-ling;YANG Yan;LIU Gang(Division of Chemistry and Ionizing Radiation Measurement Technology,Shanghai Institute of Measurement and Testing Technology,Shanghai 201203,China;College of Food Science and Technology,Shanghai Ocean University,Shanghai 201306,China;Shanghai Institute for Food and Drug Control, Shanghai 201203,China)

机构地区：[1]上海市计量测试技术研究院化学与电离辐射所,上海201203 [2]上海海洋大学食品学院,上海201306 [3]上海市食品药品检验所,上海201203

出　　处：《化学试剂》2019年第2期177-181,共5页Chemical Reagents

基　　金：国家质量监督检验检疫总局科技计划项目(2017QK129);上海市质量技术监督局科研项目(2016)

摘　　要：对人工制备的奶粉中金黄色葡萄球菌标准样品进行均匀性和不同储存条件下稳定性的实验研究。奶粉中高密度菌体和低密度菌体标准样品的均匀性统计学结果变异小,均匀性良好;两种密度菌体在-80℃保存半年后,活菌数没有显著变化,符合稳定性统计学要求,提高保存温度之后,低密度菌体标准样品可以在-20℃下保存半年以上,而高密度菌体标准样品的活菌数在-20℃下保存40 d后开始下降,直到70 d后达到稳定,继续提高保存温度,高密度菌体标准样品在4℃下保存稳定性较差,而低密度菌体标准样品在4℃可以稳定7 d。综上所述,低密度菌体的奶粉中金黄色葡萄球菌标准样品可以满足实验室质量控制和方法验证的基本需求,保障量值准确统一,保证检测结果的有效性、可比性及国际国内互认度。A group of standard reference material( SRM) candidates of high and low-level of staphylococcus aureus in milk powder was developed for the quality control and method validation in laboratory. The homogeneity and stability of the SRM candidates were investigated.The homogeneity statistical results of small variation demonstrated good uniformity of both high and low-level bacteria SRM candidates.The long-term stability investigation results showed that the numbers of living bacteria of both high and low-level were stable over 6 months under-80 ℃,and if the storage temperature was increased to-20 ℃,the low-level SRM could keep stable for 6 months,but the high-level bacteria SRM’s living number declined from 40 days and reached a plateau at70 days.Then,if the storage temperature was further increased to 4 ℃,the living number of the high-level SRM decreased dramatically in 2 days while the low-level SRM could keep stable for 7 days which is adequate for the sample delivery by using cold chain transportation.In conclusion,the low-level SRM of staphylococcus aureus in milk powder SRM candidate would be used in laboratory quality control and method validation for the promotion of the validity and comparability of the test results,and the domestic and international mutual recognition.

关 键 词：金黄色葡萄球菌 标准样品 均匀性 稳定性 

分 类 号：Q819[生物学—生物工程]