A rapid and accurate quantitative method of high performance liquid chromatography( HPLC) with fluorescence detector has been developed for the analysis of 18 kinds of amino acids in fresh tea leaves. The samples were...A rapid and accurate quantitative method of high performance liquid chromatography( HPLC) with fluorescence detector has been developed for the analysis of 18 kinds of amino acids in fresh tea leaves. The samples were minced and mixed,and extracted with ultra pure water at 90℃ for 20 min. The 6-aminoquinolyl N-hydroxy-succinimidyl carbamate( AQC) was used as pre-column derivatization reagent. Gradient HPLC separation was performed on a C_(18) column( Symmetry C_(18),3. 9 mm × 15 cm,4 μm). Good linearity between concentrations and peak areas was achieved in the concentration range of 5. 0-250 μmol/L for 18 kinds of amino acids. The method was validated by the analysis of five replicates. The 18 kinds of amino acid standards were spiked in fresh tea leaf samples and the average recovery rate was 86. 25%-109. 05% with relative standard deviations( n = 5) ranging from 6. 03% to 10. 56%. The limit of detection( LOD) for the analytes was0. 05-1. 27 μmol/L. The method was successfully applied to the analysis of the 18 kinds of amino acids in fresh tea leaves from east Dongting and west Dongting mountains in Suzhou. The results indicate that the method is simple,rapid,precise and reliable.展开更多
文摘目的建立柱前衍生高效液相色谱-串联质谱法(high performance liquid chromatography-tandem mass spectrometry,HPLC-MS/MS)测定鲜茶叶中春雷霉素的检测方法。方法样品经甲醇/水溶液提取,MCX SPE阳离子交换柱(mixed-mode cation exchanger SPE column)净化,9-氯甲酸芴甲酯[9-fluorenylmethyloxycarbonyl(Fmoc)chloride,Fmoc-Cl]衍生后测定,内标法定量。结果目标化合物在0.31~20.00μg/L范围内,线性关系良好,相关系数大于0.998(r^(2))。鲜茶叶中春雷霉素的检出限(limit of detection,LOD)、定量限(limit of quantification,LOQ)分别为2.0μg/kg和5.0μg/kg。在LOQ、2×LOQ和10×LOQ水平上加标,平均回收率为95.2%~104.0%,相对标准偏差为7.4%~13.3%。结论基于Fmoc-Cl衍生化的测定法,能有效提高检测的灵敏度、降低基质的干扰;将西马特罗作为内标使用,可以提供更为准确的检测结果,该方法满足鲜茶叶中春雷霉素的监测。
基金Supported by Open Project of the Key Laboratory of Food Quality and Safety of Jiangsu Province-State Key Laboratory Breeding Base(201603)Basic Research Project of Application of Suzhou City(SNG201622)
文摘A rapid and accurate quantitative method of high performance liquid chromatography( HPLC) with fluorescence detector has been developed for the analysis of 18 kinds of amino acids in fresh tea leaves. The samples were minced and mixed,and extracted with ultra pure water at 90℃ for 20 min. The 6-aminoquinolyl N-hydroxy-succinimidyl carbamate( AQC) was used as pre-column derivatization reagent. Gradient HPLC separation was performed on a C_(18) column( Symmetry C_(18),3. 9 mm × 15 cm,4 μm). Good linearity between concentrations and peak areas was achieved in the concentration range of 5. 0-250 μmol/L for 18 kinds of amino acids. The method was validated by the analysis of five replicates. The 18 kinds of amino acid standards were spiked in fresh tea leaf samples and the average recovery rate was 86. 25%-109. 05% with relative standard deviations( n = 5) ranging from 6. 03% to 10. 56%. The limit of detection( LOD) for the analytes was0. 05-1. 27 μmol/L. The method was successfully applied to the analysis of the 18 kinds of amino acids in fresh tea leaves from east Dongting and west Dongting mountains in Suzhou. The results indicate that the method is simple,rapid,precise and reliable.
