摘要
目的研究Ca^2+对细菌内毒素含量检测的影响,探讨其影响机制。方法向已知含量的细菌内毒素溶液中加入不同浓度的Ca^2+,用动态浊度法检测各样品中细菌内毒素含量。对检测结果进行离散系数,即CV值分析,确定干扰限值。对加入不同浓度Ca 2+的细菌内毒素进行核磁共振1 H谱研究。结果当Ca^2+浓度高于0.0020 mol/L时,检测结果的CV值较高;Ca^2+浓度越高,CV值越高,离散程度越大;当Ca^2+浓度达到1 mol/L时,检测结果低于检测限,呈现明显的假阴性。1 H谱研究发现,随着Ca^2+浓度的增高,处于低场的氢的化学位移向高场移动,Ca^2+浓度越高,移动越大。结论为获得准确的检测结果,当Ca^2+浓度高于0.0020 mol/L时,应先消除干扰,再测定细菌内毒素含量。Ca^2+可能通过影响细菌内毒素的空间构象来影响其与鲎试剂的反应。
Objective To analyze the effect from Ca^2+in detection of bacterial endotoxin content and to investigate the related influencial mechanism.Methods Different concentrations of Ca^2+were added to a known concentration of bacterial endotoxin solution,and then the bacterial endotoxin content was determined in each sample according to the dynamic turbidimetry,and analysis of a discrete coefficient(CV)was performed in determining of the interference limit.The bacterial endotoxin and bacterial endotoxin samples with different concentrations of Ca^2+were carried out by using of NMR 1 H spectrum,so as to make certain the possible influencial mechanism.Results When the Ca^2+concentration was higher than 0.0020 mol/L,appeared a Ca^2+concentration dependent pattern,the CV value from the test result was increased,with a greater degree of dispersion.When the Ca^2+concentration reached 1 mol/L,the detection result was lower than the detection limit,showing a significant false negative.It was found by NMR 1 H spectrum,as the concentration of Ca^2+increased,the chemical shift from hydrogen in the low field moved toward the high field,and a greater movement along with a high Ca^2+concentration.Conclusion In order to obtain the accurate detection results,when the Ca^2+concentration was higher than 0.0020 mol/L,the interference should be eliminated first,and then the bacterial endotoxin content could be correctly determined.The Ca^2+may interfere with interaction between bacterial endotoxin and LAL(limulus amoebocyte lysate)by means of affecting the spatial conformation of bacterial endotoxin.
作者
魏振洲
杜送田
石超
王启珍
曹鑫
马明霞
WEI Zhen-zhou;DU Song-tian;SHI Chao;WANG Qi-zhen;CAO Xin;MA Ming-xia(The First Bacterial VaccineDivision,the Diagnostic Supplies Division,Lanzhou Institute of Biological Products Co.,Ltd.,Center for Gansu Provincial Vaccine Engineering Research,Lanzhou 730046,Gansu Province,China)
出处
《微生物学免疫学进展》
2019年第6期42-46,共5页
Progress In Microbiology and Immunology
关键词
细菌内毒素
鲎试剂检测法
动态浊度法
钙离子
核磁共振1
H谱
Bacterial endotoxin
Limulus amoebocyte lysate(LAL)test
Dynamic turbidimetry method
Calcium ion
NMR 1 H spectrum
