3,4,5-三甲氧基苯甲醛标准样品的研制

Preparation of 3,4,5-Trimethoxy-benzaldehyde as Reference Substance

研究了3,4,5-三甲氧基苯甲醛标准样品的制备、均匀性和稳定性及其定值试验。用3,4,5-三甲氧基苯甲醛工业品与亚硫酸氢钠溶液加成反应,经H2SO4酸化,结晶;再用乙醇溶解,纯水稀释重结晶,得到高纯度的3,4,5-三甲氧基苯甲醛标准样品。标准样品含量测定采用气相色谱面积归一化法,并通过了均匀性检验和稳定性检验（9个月）。经定值检测,3,4,5-三甲氧基苯甲醛标准样品的质量分数为99.42%±0.07%。

Preparation, homogeneity, stability and certification of reference substance of 3,4,5-trimethoxy-benzaldehyde were studied. Highly purified reference substance of 3,4,5-trimethoxy-benzaldehyde was prepared from an industrial grade 3,4,5-trimethoxy-benzaldehyde product by NaHSO3 addition reaction followed by acidifying with H2SO4 and re-crystallization in ethanol and water. The content of 3,4,5-trimethoxy-benzaldehyde in reference substance was measured by gas chromatographic area normalization. The reference substance of 3,4,5-trimethoxy-benzaldehyde passed the test of homogeneity, and it was stable during 9 months at least. Through valuation test, 3,4,5-trimethoxy-benzaldehyde content of the reference substance was 99.42%±0.07%.