敏化光转化-化学发光法测定2,4-二氯苯酚的研究  

Photosensitized transformation-chemiluminescence determination of 2,4-dichlorophenol

作　　者：张俊丽 高慧 胡霞 宋启军 

机构地区：[1]江南大学化学与材料工程学院,无锡214036

出　　处：《分析试验室》2010年第2期77-80,共4页Chinese Journal of Analysis Laboratory

摘　　要：基于2，4-二氯苯酚（2，4-DCP）在荧光素存在下光转化后产物与氧化剂N-溴丁二酰亚胺（NBS）反应产生化学发光的现象，建立了高灵敏度检测2，4-二氯苯酚的新方法。阳离子表面活性剂十六烷基三甲基溴化铵（CTMAB）作为增敏剂可以有效的增强体系的化学发光强度。方法对浓度为7．3×10-7～7．3×10-6mol／L 及7．3×10-6～7．3×10-5mol／L的2，4-DCP分别有良好的发光响应线性关系，检出限可达4．5×10-7mol／L；通过富集浓缩可进一步降低了方法的检出限；该方法具有良好的选择性。对化学发光反应的机理做了初步探讨，认为敏化光解所产生的单线态氧与氯代酚反应生成了可发光的产物。A novel and sensitive flow injection chemiluminescence （CL） method for the determination of 2, 4-dichloro- phenol （2,4-DCP） was proposed. The analyte was phototransformed on-line to a light emitting precursor using visible light in the presence of fluorescein and the CL reaction was then triggered with an oxidant N-bromosuccinimide （NBS） using a two-channel flow injection manifold. The CL was greatly enhanced in the presence of a cationic surfactant cetyhrimethy-lammonium （CTMAB）. Under the optimized conditions, the CL intensity responded linearly to 2, 4-DCP over concentration ranges 7.3 × 10-7 - 7.3 × 10-6 mol/L and 7.3 × 10-6 - 7.3 ×10-5 mol/L, respectively. The de- tection limit was measured to be 4.5 × 10-7 mol/L and could be further lowered by preconcentration with solid phase extraction technique. By testing the potential interference substances, the proposed method also exhibited good selectivity for 2, 4-DCP determination. Finally, the possible mechanism of the CL reaction was preliminarily investigated. It was suggested that the singlet oxygen formed by the photosensitized process was responsible for the phototransformarion of the chlorophenol into a light emitting precursor.

关 键 词：2 4-二氯苯酚 化学发光 单线态氧 敏化光转化 

分 类 号：O657.3[理学—分析化学]