纳米金催化光度法检测食品中的甲醛

Catalytic Spectrophotometric Determination of Trace Formaldehyde in Food by Nanogold

中文关键词:  纳米金,催化,甲醛,分光光度法,食品

英文关键词:nanogold, catalysis, formaldehyde, spectrophotmetry, food

中文摘要:

      采用分光光度法检测以纳米金催化甲醛与菲林试剂反应生成的氧化亚铜微粒在870 nm处的吸收值，建立了一种测定食品中甲醛的新方法.研究了纳米金、菲林试剂用量及反应温度、反应时间、共存离子的影响.在最佳实验条件下，甲醛浓度在1.2～600.0 μg/mL 范围内与吸光值ΔA线性关系良好，线性回归方程为ΔA_{870 nm}=0.0014C+0.0627，相关系数为0.9992，检出限为0.45 μg/mL.加标回收率为98.0%～100.3%.该法灵敏度高，选择性好，体系干扰少，用于测定腐竹、精制粉丝、红薯粉丝和方便面中甲醛的含量获得满意的结果.

英文摘要:

      A new catalytic-spectrophotmetric method for determination of formaldehyde in food has been setup. In this method nanogold is used as the catalyst，which catalyzes the reaction of formaldehyde and Fehling reagent，and its product, cuprous oxide (Cu2O) particles, shows a broad absorption peak between 400~900 nm. A spectrohpotometric methed is used to measure the Cu2O absorption value at 870 nm. Experimental conditions of the formaldehyde-Fehling reagent-nanogold catalytic reaction were optimized. In the proposed method， the measured formaldehyde content obeyed Beer's law in the range of 1.2~600.0 μg/mL， with a linear regression equation of ΔA_{870 nm}=0.0014C+0.0627， a correlation coefficient of 0.999 2 and a detection limit of 0.45 μg/mL. Owing to high sensitivity， good selectivity， low-cost reagents， fast and good accuracy， the method has been applied to the determination of formaldehyde in food samples with satisfactory result.