溴甲酚绿-溴酸钾体系催化光度法测定痕量甲醛  

Determination of trace amount of formaldehyde based on a bromate-bromocresol green system

作　　者：陈浩 唐裕芳[2] CHEN Hao;TANG Yufang(Yueyang Vocational and Technical College,Yueyang 414000;College ofChemical Engineering,Xiangtan University,Xiangtan 411105)

机构地区：[1]岳阳职业技术学院,岳阳414000 [2]湘潭大学化工学院,湘潭411105

出　　处：《分析试验室》2020年第12期1471-1475,共5页Chinese Journal of Analysis Laboratory

摘　　要：基于硫酸介质中甲醛对溴酸钾氧化溴甲酚绿的催化作用,通过测定溴甲酚绿在443 nm处吸光度的变化,建立了一种催化动力学光度法测定食品中痕量甲醛的方法。在最佳条件下,甲醛在0.1~1.4μg/mL范围内与吸光度差值(A0-A)呈良好线性关系,线性方程为△A=0.54378-0.14656CFA,相关系数R=0.99912,检出限为0.08μg/mL,对浓度为1μg/mL甲醛10次重复测量值的相对标准偏差为1.1%。该方法可应用于香菇和腐竹中游离甲醛的直接测定。A catalytic kinetic spectrophotometric method for the determination of trace amount of formaldehyde(FA)in food based on catalytic effect of trace amount of FA on the oxidation of Bromocresol Green(BG)by potassium bromate in the presence of sulfuric acid medium,has been established.The method was monitored by measuring the decrease in absorbance of BG at 443 nm.Under the optimal experimental conditions,there was a linear relationship between the difference of absorbance(A0-A)of BG and the concentration of FA in the range of 0.1~1.4μg/m L.The linear equation was△A=0.54378-0.14656 CFA,and the correlation coefficient was0.99912 with the limit of detection of 0.08μg/m L.The relative standard deviation was 1.1%for 10 replicate measurements of 1μg/m L FA.The proposed method was successfully applied to the determination of FA in food directly.

关 键 词：溴甲酚绿 催化动力学 甲醛 

分 类 号：O657.61[理学—分析化学]