摘要
在0.025mol.L-1NH4OAc-HOAc(pH 5.0)溶液中,SO2吸附在滴汞电极上,于峰电位-0.66 V(vs.SCE)处产生灵敏的二阶导数极谱还原波,引入氯化十六烷基吡啶(CPC)后,峰电流I″p的灵敏度提高0.81倍,其I″p与SO2浓度在0.2-6.0 mg.L-1范围内呈线性关系,检出限为0.1 mg.L-1,S2-、NO2-、醛类及带色物质等无干扰。用于食品中SO2的测定,样品加标回收率为90.0%-114.0%,RSD为0.1%-5.2%。
In an acetate buffer of pH 5. 0, sulfur dioxide was adsorbed on the dropping mercury electrode, producing a sensitive polarographic reduction wave at its peak potential （Ep） of -0. 66 V （vs. SCE）. The sensitivity of the 2nd derivative of its peak current （I″p） was raised by 0. 81 times by the addition of N-cetyl pyridine chloride. Linear relationship between I″p and concentration of SO2 was obtained in the range of 0. 2-6. 0 mg· L^-1 , with a detection limit of 0. 1 mg · L^-2. Appropriate amounts of sulfide, nitrite and aldehydes were tolerable. In the application of the proposed method to the analysis of 18 kinds of foodstuffs, values of RSD＇s （n=6） found were in the range of 0. 1%-5. 2%. Values of recovery found by the Standard addition method were in the range of 90. 0% -114. 0%.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
2007年第4期303-305,307,共4页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
单扫示波极谱法
二氧化硫
食品
氯化十六烷基吡啶
Single-sweeping oscillopolarography
Sulfur dioxide
Foodstuff
N-cetyl pyridine chloride
