摘要
取固体样品(如糕点、肉肠等)2.000g,或液态样品(如饮料等)10.00mL,加少量水稀释后,加入220g·L^(-1)乙酸锌和106g·L^(-1)亚铁氰化钾溶液各2mL沉淀蛋白质并离心除去;取半固体样品(如果冻等)2.000g,加水稀释后用氨水(1+1)溶液调节其酸度至pH 7~8,上述3种样品溶液均分别用水定容至25.0mL。所得溶液进行高效液相色谱分离,以TSK Eclipse XDB-C18色谱柱为固定相,和pH 5.0的甲醇-三乙胺缓冲溶液(1+9)为流动相。苯甲酸和山梨酸的质量浓度均在0.1~10.0mg·L^(-1)内与峰面积呈线性关系,检出限(3S/N)分别为1.8,1.2mg·kg^(-1)。按标准加入法在3个浓度水平上进行回收试验,回收率在90%~97%之间,测定值的相对标准偏差(n=6)均小于10%。
The solid sample, e.g. cake, sausage and etc. , （2. 000 g） or liquid sample, e. g. , drinks etc. （10. 00 mL） was taken and diluted with some water. 2 mL of 220 g · L^-1 zinc acetate solution and 2 mL of 106 g · L^-1 potassium ferrocyanide solution were added to precipitate protein and to remove it by centrifuge. In case of semi- solid sample, e.g. , jelly, 2. 000 g were taken and diluted with water. The acidity was adjusted to pH 7 to 8 with ammonia （1＋1） solution. The sample solution described above was made up to 25.0 mL with water, and separated by HPLC using TSK Eclipse XDB-C18 column as stationary phase and mixed solution of methanol and triethylamin （1＋9） （pH 5. 0） as mobile phase. Linear relationships between values of peak area and mass concentration of benzoic acid and sorbic acid were found in the same range of 0. 1--10. 0 mg·L^-1 , with detection limits （3S/N） of 1.8, 1. 2 mg · kg^-1 , respectively. Test for recovery was made by standard addition method at 3 concentration levels, giving results in the range of 90%--97%, with RSDs （n=6） less than 10%.
出处
《理化检验（化学分册）》
CSCD
北大核心
2017年第4期447-450,共4页
Physical Testing and Chemical Analysis(Part B:Chemical Analysis)
