【摘要】 提出一种催化动力学光度法测定生物样品中草酸的方法。基于在硫酸介质中，草酸能有效地催化重铬酸钾氧化丁基罗丹明Ｂ褪色，当反应温度为６５℃、反应时间１２ ｍ ｉｎ时，非催化反应溶液的吸光度Ａ０ 和催化反应溶液吸光度Ａ 的ｌｎ Ａ０Ａ 值与草酸浓度在０．２０～１０．０８ μｇ／ｍ Ｌ之间存在良好线性关系。反应体系用高浓度ＮａＯＨ 终止后室温下可稳定２ ｈ 以上。催化反应的表观活化能为１３．５３ ｋＪ／ｍ ｏｌ。方法可直接用于菠菜、童尿、草莓晶等生物样品中草酸的测定。更多还原

【Abstract】 A new catalytic kinetic spectrophotometric method for determination of micro oxalate has been developed. The method is based on the catalytic effect of oxalate on the oxidation of potassium bichromate with butyl rhodamine B in 0.1 mol/L sulfuric acid medium. Under the reaction temperature of 65℃ and reaction time of 12 minutes, the logarithm of the ratio between the absorbance of noncatalytic reaction system ( A 0) and the absorbance of catalytic reaction system ( A ), ln( A 0/ A ), is linearly related to the concentration of oxalate in the range from 0.2105 to 10.0775 μg/mL. The method has been applied to the determination of oxalate in the mixture sample and several biological samples with satisfactory results.更多还原