A methodology regarding the preparation and certification of certified reference material ( CRM) of allure red solution was presented. After the qualitative analysis on pure substance of allure red by liquid chromatography -mass spectrometry(LC -LTQ/MS) and 'H NMR spectrum, the purity of allure red was certified by high performance liquid chromatography ( HPLC) , the purity certification of allure red was performed at 240 nm with methanol and 0. 1 mol/L ammonium acetate solution as mobile phase, and the Intersil ODS-C18 column(250 mm ×4. 6 mm, 5 μm) was used for analysis. The certification purity of allure red was 99.61% . To verify the result, six certification labs were performed, at the same time, the water content and volatile impurity were determined by the total gravimetric analysis ( TGA). Allure red solution CRM was prepared by the gravity-volume method. After the tests of homogeneity and stability, the concentration of allure red solution CRM was certified and the uncertainty was evaluated. The certified result was 100 mg/L and the expanded relative uncertainty was 1.0% ( k =2). The allure red solution CRM was approved as a national CRM and could be applied in food safety detection.%建立了食用合成色素诱惑红溶液标准物质的制备和定值方法,研制了100 mg/L的诱惑红溶液标准物质.采用制备液相色谱对筛选的市售原料纯化,得到纯度大于99％的诱惑红纯品；通过核磁共振(1H NMR谱)和液相色谱-质谱(HPLC - LTQ/MS)准确定性分析后,利用高效液相色谱法(HPLC)对诱惑红纯物质进行纯度定值.以0.1 mol/L乙酸铵和甲醇为流动相进行等度洗脱,采用Intersil ODS-C18(250 mm×4.6 mm,5μm)进行分离,检测波长240 nm.为保证纯度测量的准确性,采用多家联合定值对诱惑红的纯度进行定值,诱惑红纯物质的定值纯度为99.61％(λ=240 nm).诱惑红溶液标准物质经重量-容量法配制后,进行均匀性和稳定性实验,浓度赋值后进行不确定度评定,诱惑红溶液的量值为100 mg/L,扩展相对不确定度为1.0％(k=2).该溶液标准物质已批准为国家级标准物质,可为相关部门提供检测标准.
展开▼
