水的酸碱度对Bradford法检测蛋白质含量的影响

Effect of water pH value on protein content with Bradford method

目的探讨水酸碱度的变化对Bradford法检测蛋白质含量的影响。方法用pH分别为4.0(pH=4.0组)、7.0(pH=7.0组)和10.0(pH=10.0组)的双蒸水配置Bradford法所需要的试剂,绘制标准曲线,检测标准蛋白浓度,比较水的酸碱度的变化对标准曲线的影响。结果pH=4.0组和pH=7.0组的标准曲线拟合度较pH=10.0组标准曲线拟合度明显增高;pH=4.0组和pH=7.0组检测的蛋白质含量与已知蛋白浓度相比差别无统计学意义(P>0.05);pH=10.0组检测蛋白质的含量与已知蛋白浓度、pH=7.0组和pH=4.0组相比差别均有统计学意义(P<0.05),pH=7.0组和pH=4.0组检测蛋白质含量的准确性高于pH=10.0组。结论双蒸水酸碱度的变化可以影响Bradford法检测蛋白质含量的精确度。

Objective To study the effect of water pH value on protein content with Bradford method.Methods Double distilled water with different pH（4.0,7.0 and 10.0）was used to dissolve the agents needed in Bradford method.The standard curves were made to detect the fitting situations and standard content of protein.According to the protein content,the effect of pH on standard curves was estimated.Results The fitting situations in the group of pH equaled to 7.0 and 4.0 were much better than that in the group of pH equaled to 10.0.There was no obvious difference in protein contents among the known protein concentration,pH equaled to 7.0 and 4.0 groups（P〉0.05）.There was obvious difference in protein content between pH equaled to 10.0 group and pH equaled to 7.0 group,pH equaled to 4.0 group or the known protein concentration（P〈0.05）.The accurate rates were higher in the pH equaled to 7.0 and 4.0 groups than those in the pH equaled to10.0 group.Conclusion The changes of water pH value could affect the accuracy of detecting protein content with Bradford method.