维生素C对直接法测定高(低)密度脂蛋白胆固醇的影响

Effects of Vitamin C on the Direct Measurement of Serum High/Low Density Lipoprotein Cholesterol

目的:探讨维生素C(Vit C)对直接法测定高密度脂蛋白胆固醇(HDL-CH)和低密度脂蛋白胆固醇(LDL-CH)结果的影响。方法:两项目分别测定加入不同浓度Vit C的血清,对其结果进行比较、分析。结果:Vit C对利用Trinder反应进行检测的HDL-CH和LDL-CH结果有显著负干扰作用,测定值与干扰物浓度成负相关关系,当Vit C浓度达到1 600mg/L时,其影响度达到100%,也就是测定结果为0,当Vit C浓度低于200mg/L时,LDL-CH检测结果基本不受其影响(t=2.08,P>0.05);高密度脂蛋白胆固醇受Vit C的影响程度要远高于低密度脂蛋白胆固醇。结论:在用直接法测定HDL-CH、LDL-CH时,其检测原理是用不同的方法分别游离出HDL-CH和LDL-CH,然后再测定其胆固醇的含量;Trinder反应是构成胆固醇测定的基础,而Vit C具有强的还原性,与色原性物质竞争H2O2,从而使氧化过程中产生的H2O2被消耗,导致色素形成减少,同时Vit C也可还原第二步反应中形成的红色醌类化合物,使反应液颜色减弱,吸光度下降,从而使测定结果偏低。

Objective：To explore whether or not vitamin C（Vit C） has impacts on the result of direct measurement of serum high density lipoprotein cholesterol（HDL-CH） and low density lipoprotein cholesterol（LDL-CH）.Methods：Serum HDL-CH and LDL-CH levels were determined after the treatment of different concentrations of Vit C.Results：Vit C had remarkable negative interference effect on the results of Trinder Reaction measurement of HDL-CH and LDL-CH,the determination value and the density of the interferent were inversely correlated.When the level of Vit C density reached 1 600 mg/L,its influence rates was 100% and the determination value was 0;when the Vit C density was lower than 200 mg/L,the determination value of LDL-CH was basically not affected（t=2.08,P0.05）.Compared with the effect on LDL-CH,the impact of Vit C was more significant on HDL-CH.Conclusion：Vit C has impact on the results of direct measurement of serum HDL-CH and LDL-CH,especially for the HDL-CH.