Journal of Integrative Agriculture ›› 2012, Vol. 12 ›› Issue (11): 1861-1870.DOI: 10.1016/S1671-2927(00)8721

• 论文 • 上一篇    下一篇

Determination of Pesticide Residue Cartap Using a Sensitive Fluorescent Probe

 JING Xu, DU Li-ming, WU Hao, WU Wen-ying , CHANG Yin-xia   

  1. Analytical and Testing Center, Shanxi Normal University, Linfen 041000, P.R.China
  • 收稿日期:2012-02-27 出版日期:2012-11-01 发布日期:2012-11-24
  • 通讯作者: Correspondence DU Li-ming, Tel: +86-357-2057969, E-mail: lmd@dns.sxnu.edu.cn
  • 作者简介:JING Xu, E-mail: lmd@dns.sxnu.edu.cn;
  • 基金资助:

    This work was supported by the Research Fund for the Doctoral Program of Higher Education of China (20091404110001).

Determination of Pesticide Residue Cartap Using a Sensitive Fluorescent Probe

 JING  Xu, DU  Li-ming, WU  Hao, WU  Wen-ying , CHANG  Yin-xia   

  1. Analytical and Testing Center, Shanxi Normal University, Linfen 041000, P.R.China
  • Received:2012-02-27 Online:2012-11-01 Published:2012-11-24
  • Contact: Correspondence DU Li-ming, Tel: +86-357-2057969, E-mail: lmd@dns.sxnu.edu.cn
  • About author:JING Xu, E-mail: lmd@dns.sxnu.edu.cn;
  • Supported by:

    This work was supported by the Research Fund for the Doctoral Program of Higher Education of China (20091404110001).

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摘要： The insecticide cartap (CP) is non-fluorescent in aqueous solutions. This property makes its determination through direct fluorescent method difficult. In acidic medium and at room temperature, palmatine (PAL) can react with cucurbit[7]uril (CB[7]) to form stable complexes, and the fluorescence intensity of the complex is greatly enhanced. Significant quenching of the fluorescence intensity of the CB[7]-PAL complex was observed with the addition of cartap. Based on the significant quenching of the supramolecular complex fluorescence intensity, a new spectrofluorimetric method with high sensitivity and selectivity was developed to determine cartap in aqueous solution. The fluorescence quenching values (DF) showed good linear relationship with cartap concentrations from 0.009 to 2.4 μg mL-1 with a detection limit 0.0029 μg mL-1. The proposed method had been successfully applied to the determination of cartap residues in grain and vegetable with recoveries of 87.4-103%. In addition, the association constants of the complexes formed between the host and the guest were determined. The competing reaction and the supramolecular interaction mechanisms between the cartap and PAL as they fight for occupancy of the CB[7] cavity were studied using spectrofluorimetry, 1H NMR and molecular modeling calculations.

关键词: cartap , cucurbit[7]uril , palmatine , fluorescent probe

Abstract: The insecticide cartap (CP) is non-fluorescent in aqueous solutions. This property makes its determination through direct fluorescent method difficult. In acidic medium and at room temperature, palmatine (PAL) can react with cucurbit[7]uril (CB[7]) to form stable complexes, and the fluorescence intensity of the complex is greatly enhanced. Significant quenching of the fluorescence intensity of the CB[7]-PAL complex was observed with the addition of cartap. Based on the significant quenching of the supramolecular complex fluorescence intensity, a new spectrofluorimetric method with high sensitivity and selectivity was developed to determine cartap in aqueous solution. The fluorescence quenching values (DF) showed good linear relationship with cartap concentrations from 0.009 to 2.4 μg mL-1 with a detection limit 0.0029 μg mL-1. The proposed method had been successfully applied to the determination of cartap residues in grain and vegetable with recoveries of 87.4-103%. In addition, the association constants of the complexes formed between the host and the guest were determined. The competing reaction and the supramolecular interaction mechanisms between the cartap and PAL as they fight for occupancy of the CB[7] cavity were studied using spectrofluorimetry, 1H NMR and molecular modeling calculations.

Key words: cartap , cucurbit[7]uril , palmatine , fluorescent probe