丙酮和乙醇双水相萃取、荧光法测定痕量维生素B_2  

Determination of Trace Vitamin B_2 by Fluorimetry after Aqueous Two-Phase Extraction Based on Acetone and Ethanol

作　　者：龙文清[1] 

机构地区：[1]井冈山学院化学化工学院,江西省配位化学重点实验室,江西吉安343009

出　　处：《光谱学与光谱分析》2007年第10期2098-2101,共4页Spectroscopy and Spectral Analysis

基　　金：江西省教育厅科技基金项目(赣教计字[2001]387号)资助

摘　　要：诸如乙醇、丙酮和乙腈等水溶性小分子有机溶剂在盐的作用下能够形成双水相体系用于目标物质的萃取。正是基于此,提出了丙酮-盐-水和乙醇-盐-水体系双水相萃取、荧光测定痕量维生素B2的新方法。研究了盐和有机溶剂种类及用量、萃取时间、共存物和酸度等的影响。发现,丙酮-(NH4)2SO4-H2O和乙醇-(NH4)2SO4-H2O体系对维生素B2的一次性萃取率分别为97.6%～98.4%和94.2%～95.5%;在最适条件下,两种体系测定维生素B2的线性范围分别为1.5×10-7～3.5×10-6mol.L-1和2.0×10-7～1.5×10-6mol.L-1,检出限分别为0.031和0.041μg。该方法已成功用于片剂和注射液中维生素B2的测定,相对标准偏差1.5%～2.2%,与中国药典方法对照,相对误差-1.8%～1.1%。与传统的液-液萃取和固相萃取比较,本方法具有操作简便、萃取率高、干扰小、低毒等显著特点。Small molecular water-miscible organic solvent, such as ethanol, acetone and acetonitrile, can be used to form aqueOus two-phase system for extraction of analytes in the presence of salts. Just based on it, the acetone-salt-H2O and the ethanol-salt- H2O systems were developed for the determination of trace vitamin B2 coupled with fluorimetry after aqueous two-phase extraction. Various factors including the type and amount of salts and organic solvents, extraction time, coexistent substance, and pH were studied. The experimental results show that the extraction efficiencies of vitamin B2 in the acetone-salt-H2O and the etha- nol-salt-H2O system were 97.6%-98. 4% and 94. 2%-95.5%, respectively, in one-step extraction. Under the optimal conditions, these two extraction techniques gave linear dynamic ranges of 1.5 ×10^-7-3. 5×10^-6 mol ·L^-1 and 2.0×10^-7-1.5 × 10^-6 mol· L^-1 , with detection limits of 0. 031 and 0. 041μg, respectively. Both techniques were applied directly to determination of vitamin B2 in pharmaceutical tablets and injections with satisfactory results. The relative errors were --1.8%-1.1% as compared with China pharmacopoeia and the relative standard deviations were 1.5 %-2. 2% for vitamin B2 in the above samples. Compared with conventional liquid-liquid extraction or solid-phase extraction, these methods have outstanding advantages such as simple operation, high extraction efficiency, little interference with analytes and low toxicity.

关 键 词：双水相萃取 维生素B2 荧光测定法 丙酮 乙醇 硫酸铵 

分 类 号：O657.3[理学—分析化学] O658.2[理学—化学]