Feasibility study of micro kinetic-chromogenic method for bacterial endotoxin detection
Objective:To establish a micro kinetic-chromogenic method and verify its feasibility for bacterial endo-toxin testing.Methods:Establish an addition system for micro kinetic-chromogenic lysate reagent with 25 μL and 25 μL sample,respectively.Methodological validation was conducted by examining accuracy and precision,linear-ity and range,minimum detection limit,and reagent durability.Two methods,kinetic-chromogenic method and micro kinetic-chromogenic method,were used to compare the applicability of the method to 39 different varieties.Results:The recovery rates of three doses of 0.03,0.3,and 3.0 EU·mL-1 in six repeated experiments were(96.19±16.68)%,(92.53±10.17)%,and(89.54±25.84)%,respectively.The absolute value of the correlation coefficient(r)for the six standard curves is(0.997 7±0.002 3).When the minimum sensitivity concentration of lysate reagent is 0.01 EU·mL-1,the reaction time is(3 896.0±279.6)s,which is lower than the reaction time of the negative control.The durability test results meet the requirements by two micro kinetic-chromogenic lysate reagents from different manufacturers.The research results on variety adaptability show that the recovery rates of 39 varieties are between 50%and 200%,the effectiveness of the two methods is the same.Conclusion:The accuracy and precision,linearity and range,minimum detection limit,and reagent durability of micro kinetic-chromogenic method all meet the requirements of method validation.The variety applicability is equivalent to that of the traditional kinetic-chromogenic method,so this method can be used for bacterial endotoxin detection of routine samples.