微波消解试样-催化动力学光度法测定腌菜中亚硝酸根  

Catalytic-Kinetic Photometric Determination of Nitrite in Pickles with Micro-Wave Assisted Sample Digestion

作　　者：陈玉静[1] 王玉宝[1] 姜华[1] 唐清华[1] 

机构地区：[1]鲁东大学化学与材料科学学院,烟台264025

出　　处：《理化检验（化学分册）》2008年第7期627-628,631,共3页Physical Testing and Chemical Analysis(Part B:Chemical Analysis)

基　　金：鲁东大学科研基金资助(20052903)

摘　　要：腌菜试样用稀磷酸及过氧化氢置于PTFE罐中,在微波炉先后在400 W及500 W消解2 min及4 min,所得试样溶液于100 mL容量瓶中定容供光度测定。在稀磷酸介质中偶氮胂Ⅰ溶液与溴酸钾溶液的氧化褪色反应因亚硝酸根的存在而催化加速。有及没有亚硝酸根存在的两份相同试液的吸光度A及A_0之差△A与亚硝酸根质量浓度在50μg·L^(-1)以内呈线性关系,其检出限为0.82μg·L^(-1)。用此方法分析3件腌菜试样,测定结果的相对标准偏差(n=6)均小于2%。以此样品为基体,加入亚硝酸根标准溶液进行回收试验,测得的回收率在98.0%～102.0%之间。Sample of pickles was digested with dil. HaPO4 and H2O2 in PTFE vessel and heated in a microwave oven at 400 W for 2 min and 500 W for 4 min. The sample solution obtained was diluted to 100 mL in a volumetric flask and used for photometric determination. In dil. HaPO4 medium, the oxidative color-fading reaction of arsenam I with KBrOa solution was catalyzed by the presence of NO2^-. Difference of values of absorbances （△A） measured （at 510 nm） in the colored solutions with （A） and without （A0） the presence of nitrite were directly proportional to the concentrations of NO2^- in the range within 50μg · L^-1 with a detection limit of 0. 82μg · L^-1. The proposed method was used in the analysis of 3 pickle samples, giving values of RSD （n=6） less than 2% and values of recovery in the range of 98. 0%-102. 0% .

关 键 词：催化动力学光度法 微波加热消解试样 腌菜 偶氮胂I 亚硝酸根 

分 类 号：O657.32[理学—分析化学]