丙酮双水相萃取预富集荧光法测定痕量1-萘胺  

Determination of trace 1-naphthylamine by fluorimetry after aqueous two-phase extraction preconcentration based on acetone

作　　者：龙文清[1] 黄春芳[1] 陈华龙[1] 

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

出　　处：《分析试验室》2008年第12期19-22,共4页Chinese Journal of Analysis Laboratory

基　　金：吉安市重点科技(吉市科计字[2006]20号)项目资助

摘　　要：基于丙酮水溶液在适当电解质作用下能形成双水相及1-萘胺能发射荧光的特点，建立了一种丙酮．电解质-水体系双水相萃取、蠕动泵进样荧光法测定1．萘胺的新方法。研究了电解质的种类和用量、丙酮体积、1．萘胺浓度、温度、酸度和共存物等的影响。发现在最佳萃取体系丙酮．K1P04．H20中，1．萘胺的一次性萃取率82．7％～89．9％，测定1-萘胺的线性范围7．2×10^-8～6．0×10^-7mol／L，检出限2．6×10^-9mol／L。方法用于强化水样和豆芽样品中痕量1-萘胺的测定，回收率96％～106％，相对标准偏差2．8％～5．8％。Acetone can be used to form aqueous two-phase system for extraction of analytes in the presence of electrolytes and 1-naphthylamine can emit fluorescence signal （λex/λcm = 338/413 nm） in acetone medium. Just based on these, an acetone-electrolyte-H20 system was developed for the determination of trace 1-naphthylamine coupled with fluorimetry by a peristaltic pump introducing sample after aqueous two-phase extraction. Various factors were studied including the type and amount of electrolytes, the volume of acetone, the concentration of the analyte, temperature, coexisting substance, and pH. The experimental results show that the extraction efficiencies of 1-naphthylamine in the optimal system of acetone-K3 PO¤4-H2O were 82.7 % - 89.9 % in one-step extraction. The extraction technique combined with fluorimetry gave linear dynamic range of 7.2 × 10^-8 - 6.0 × 10^-7 mol/L with a detection limit of 2.6 × 10^-9 mol/L. The method was directly applied to the determination of 1-naphthylamine in spiked water and bean sprout samples with recoveries of 96% - 106% and relative standard deviations of 2.8% - 5.8%. Compared with conventional liquid-liquid extraction, the method has outstanding advantages such as simple operation, high extraction efficiency and enrichment factor, little interference with analyte, low consumption of extraction solvent, and low toxicity.

关 键 词：双水相萃取 荧光测定法 1-萘胺 丙酮 磷酸钾 

分 类 号：O658.2[理学—分析化学] O657.3[理学—化学]