摘要
在PH 7.0磷酸盐介质和室温(25℃)条件下,亚硫酸盐和孔雀石绿产生加成反应.在最大吸收波长615nm处,用固定时间法测量染料的褪色强度.间接表观摩尔吸光系数(ε)为6.84×10~4,线性范围为0～0.60mg·L^(-1).结合通气蒸馏法,可消除许多共存物质的影响,方法有极高的选择性.用于测定食品中总亚硫酸盐的含量.结果与改良Rankine比色法相一致.
It is found that in a solution of pH 7. 0 phosphate buffer medium and at 25℃ sulfites react with malachite green (MG) to form an addition product, causing a color-fading of the MG dye which has an absorption maxima at 615nm. The determination of sulfites is carried out by measuring the intensity of colour-fading at a defi-nite time (5min) after the addition of MG solution and at the wavelength of 615nm. The indirect apparent molar absorptivity is 6. 84×10~4L · mol^(-1) · cm^(-1), and Beer's law holds in the concentration range of 0 - 0. 60mg of SO3^(2-) er liter. The interferences of many co-existing substances are eliminated by a separation of distillation- The method has been used in the determination of sulfites in foods. The results obtained checked very well with that obtained by the modified Rankine colorimetric method.
出处
《理化检验（化学分册）》
CAS
CSCD
北大核心
1999年第1期16-17,20,共3页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
关键词
亚硫酸盐
动力学光度法
食品添加剂
测定
Sulfites Malachite green Addition reaction Kinetic photometric method Foodstuff
