胆固醇和甘油环糊精水溶液标准物质的研制

摘要

Objective Preparation of aqueous reference materials for cholesterol and glycerol.Methods Study on reference materials.The certified reference materials GBW09203b and GBW09149 were weighed accurately and dissolved into 20% of methyl cyclodextrin aqueous solution to prepare six kinds of candidate reference materials of cholesterol and glycerol according to the concentration.The materials were tested for homogeneity and stability using routine methods.The reference methods of isotope dilution liquid chromatography tandem mass spectrometry (ID-LC/MS/MS) were used to determine the concentration of cholesterol and glycerol to evaluate the accuracy of the certified values.Meanwhile, the blank verification test was carried out.The expanded uncertainty was the combination of standard uncertainty of measurement, unhomogeneity and instability.Results It showed that the six candidate reference materials were homogeneous and stable for at least 1 year at-70 ℃ and-20 ℃.The certified values (reference value ± expanded uncertainty,mmol/L) were as follows,for cholesterol:0.65±0.01,1.31 ±0.01,2.57±0.02,5.21±0.06,7.71±0.08,10.24±0.06;for glycerol:0.29±0.01,0.58±0.01,1.22±0.02,2.24±0.02,3.46±0.04,4.52 ±0.04.The results of reference methods were consistent with the certified values.Blank validation tests showed that the concentration of the analytes would not be affected by the reagent and the blank matrix.Conclusions Certified reference materials for cholesterol and glycerol in aqueous solution have been prepared successfully.These materials are homogeneous and stable, and the certified values are reliable.Therefore the materials have been approved to be the Certificate Reference Materials of GBW 09823, GBW 09824, GBW 09825, GBW09826, GBW09827 and GBW 09828.%目的 研制胆固醇和甘油水溶液基质的标准物质.方法 标准物质研究.以胆固醇标准物质GBW09203b和甘油标准物质GBW09149为原料,溶解到20%甲基环糊精溶液中,称量配制法制备6个浓度水平的候选标准物质.用常规方法进行均匀性和同步稳定性研究.用参考方法-同位素稀释液相色谱串联质谱(ID-LC/MS/MS)测定候选标准物质以评价定值的准确性,同时进行空白验证试验.评价不均匀性、不稳定性和定值引入的不确定度,并计算总不确定度.结果 6个浓度水平标准物质的研究结果显示均匀性良好,在-70 ℃和-20 ℃保存至少可稳定1年.定值结果("标准值±扩展不确定度",单位:mmol/L)如下,胆固醇:0.65±0.01,1.31 ±0.01,2.57±0.02,5.21±0.06,7.71±0.08,10.24±0.06;甘油:0.29±0.01,0.58±0.01,1.22±0.02,2.24±0.02,3.46±0.04,4.52 ±0.04.参考方法测定结果与定值结果一致.空白验证结果显示试剂、空白基质不会对待测物的浓度产生影响.结论 成功研制了胆固醇和甘油水溶液基质的候选标准物质.物质均匀、稳定,定值可靠,已被批准为国家一级标准物质(GBW 09823、GBW 09824、GBW 09825、GBW09826、GBW09827和GBW 09828).