Gas chromatographic method for the determination of hexaconazole residues in black tea  

作　　者：Chinnachamy KARTHIKA Paul James SACHIN 

机构地区：[1]United Planter's Association of South India (UPASI) Tea Research Foundation, Tea Research Institute, Nirar Dam Branch Post Office (BPO), Valparai 642127, Coimbatore District, Tamil Nadu, India

出　　处：《Journal of Zhejiang University-Science B(Biomedicine & Biotechnology)》2008年第2期160-164,共5页浙江大学学报（英文版）B辑（生物医学与生物技术）

基　　金：Project supported by the National Tea Research Foundation, Kolkata,India

摘　　要：A highly reliable, quantitative and sensitive analytical method for determining the residues of the fungicide, hexaconazole in black tea is described. The proposed method is based on liquid-liquid extraction followed by gas chromatographic determination, using nitrogen phosphorus detector (GC-NPD) for the identification and quantitation of hexaconazole. The most appropriate solvent mixture for extracting hexaconazole residues from black tea was n-hexane:acetone at 1:1 (v/v). The extract was cleaned up by adsorption column chromatography using activated florisil. Performance of the method was assessed by evaluating quality parameters such as recovery value, repeatability, reproducibility, linearity and limits of detection and quantitation. When the method was assessed for repeatability, the percentage of recovery ranged between 86% and 96% while the relative standard deviation was between 0.30% and 2.35%. In studies on reproducibility the recovery ranged from 81% to 85% and relative standard deviation from 1.68% to 5.13%, implying that the method was reliable. A field trial was conducted to verify the application of this method with real samples. Results prove that the validated method was suitable for extracting hexaconazole residues.A highly reliable, quantitative and sensitive analytical method for determining the residues of the fungicide, hexaconazole in black tea is described. The proposed method is based on liquid-liquid extraction followed by gas chromatographic determination, using nitrogen phosphorus detector （GC-NPD） for the identification and quantitation of hexaconazole. The most appropriate solvent mixture for extracting hexaconazole residues from black tea was n-hexane：acetone at 1 ：1 （v/v）. The extract was cleaned up by adsorption column chromatography using activated florisil. Performance of the method was assessed by evaluating quality parameters such as recovery value, repeatability, reproducibility, linearity and limits of detection and quantitation. When the method was assessed for repeatability, the percentage of recovery ranged between 86% and 96% while the relative standard deviation was between 0.30% and 2.35%. In studies on reproducibility the recovery ranged from 81% to 85% and relative standard deviation from 1.68% to 5.13%, implying that the method was reliable. A field trial was conducted to verify the application of this method with real samples. Results prove that the validated method was suitable for extracting hexaconazole residues.

关 键 词：HEXACONAZOLE RESIDUES Black tea Florisil Gas chromatography-nitrogen phosphorus detector （GP-NPD） 

分 类 号：O657.7[理学—分析化学]