摘要
在约0.008 mol.L-1硫酸介质中,Fenton反应产生的羟基自由基可使考马斯亮蓝G250(CBB G250)显著褪色。在CCB G250的吸收峰582 nm波长处测得的吸光度降低值(ΔA)与羟自由基(.OH)浓度在25 mg.L-1以下的范围内呈线性关系。根据Fenton反应及与方程式所示的化学计量关系,可用过氧化氢的浓度代表羟自由基浓度。用过氧化氢标准溶液对此反应体系作精密度试验,测得相对标准偏差(n=6)为0.6%。应用此方法对抗坏血酸等9种抗氧化剂的清除羟基自由基性能进行了测定。结果表明此方法可方便地应用于抗氧化剂的筛选。
In the dilute H2SO4 medium of ca.0.008 mol·L-1,the hydroxyl free radical,·OH,produced by the Fenton reaction reacted with Coomassie brilliant blue G250（CBB G250）,leading to color fading of the dye.Intensity of decrease of absorbance of CBB G250 measured at its absorption maximum of 582 nm（ΔA582） was found to keep linear relationship with the concentration of ·OH in the range within 25 mg·L-1.Based on the stoichiometric relationship between the reactant H2O2 and the product ·OH as shown by the Fenton reaction equation,the concentration of ·OH was expressed in terms of the concentration of H2O2.Precision of the color-fading reaction system was tested with standard solution of hydrogen peroxide for 6 replicate determinations,giving value of RSD（n=6） 0.6%.Based on these facts and on the results of its application to the determination of scavenging rate of several antioxidants against ·OH,this method was found to be feasible for the selection of anti-oxidants.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2010年第5期475-477,481,共4页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
