碱性橙Ⅱ纯度标准物质的研制

Research on a Purity Certified Reference Material of Basic Orange Ⅱ

通过原料提纯、定性分析、定量分析、均匀性试验、稳定性试验、联合定值和不确定度评定等方法对碱性橙Ⅱ的纯度标准物质进行了研究.对市售的碱性橙Ⅱ原料进行重结晶,制备了候选标准物质.候选物经提纯、干燥后,封装在棕色玻璃瓶中.采用分层随机抽样的方法,选取数个样品瓶进行均匀性和稳定性的研究,结果表明所制备的碱性橙Ⅱ标准物质具有良好的均匀性和足够的稳定性.利用红外光谱、高分辨质谱和核磁共振H谱确证了碱性橙候选标准物的化学成分.联合了7个资质实验室进行了合作认证.采用质量平衡法(含液相色谱法面积归一化分析、含水率、灰分含量及残留溶剂分析)对其进行了纯度分析.结果表明,该标准物质的纯度认证值为99.2%,相对扩展不确定度为1.0%(k=2).该纯度标准物质已被鉴定为国家二级标准物质,编号为GBW(E)100372,可望用于食品和化妆品分析中的仪器校准和方法评定.

A purity certified reference material for Basic Orange II was studied by means of raw material purification,qualitative analysis,quantitative analysis,homogeneity test,stability test,as well as characterization and uncertainty evaluation.The candidate standard substance was prepared by recrystallization of purchased Basic Orange II.The candidates were purified,dried,and then encapsulated in brown glass bottles.The homogeneity and stability of several sample bottles were studied by stratified random sampling.The chemical composition of the candidate reference material of Basic Orange II was confirmed by infrared(IR)spectrum,high resolution mass spectrometry(MS)and proton nuclear magnetic resonance(NMR).7 qualified laboratories were cooperated for certification of Basic Orange II.The purity of the product was analyzed by mass balance method(concluding area normalization,water content,ash content and residual solvent analysis by liquid chromatography).The results showed that the certified value of the purity reference material was 99.2%and the relative expansion uncertainty was 1.0%(k=2).The purity reference material was identified as the national grade II certified reference materials,which was numbered GBW(E)100372,and was expected to be used in the calibration of instruments and method evaluation in food and cosmetic analysis.