期刊
JOURNAL OF CHROMATOGRAPHY A
卷 912, 期 1, 页码 73-82出版社
ELSEVIER
DOI: 10.1016/S0021-9673(01)00548-9
关键词
radical scavengers; luminol luminescence; detection; LC; antioxidants; 2,2 '-diphenyl-1-picrylhydrazyl
Two methods for the on-line detection in HPLC eluates of analytes possessing radical scavenging activity were improved and compared. The instrumental set-up of the method that is based on on-line inhibition of luminol chemiluminescence (CL) by antioxidants was improved using better quality syringe pumps, employing a diode array detector, and introducing a mixing/neutralisation coil and a pulse damper. Sensitivity of the HPLC-CL detection increased by a factor of 4. Post-column neutralisation of eluates improved compatibility of this detection method with acidified HPLC eluents. The second method, which is based on the post-column quenching of 2,2'-diphenyl-1-picrylhydrazyl radical (DPPH.), was improved by readjusting composition and flow-rate of the reagent, mounting an additional pulse damper and detecting unreacted DPPH. with a detector equipped with a tungsten lamp. Purging of the DPPH. solution with He gas prior to analysis was introduced. This led to 30-fold better detection limits. The improved methods were compared with respect to limits of detection, the radical scavenging mechanism involved, compatibility with common HPLC solvents and pH range, and some technical aspects. The techniques described have high potential for the rapid identification of radical scavengers in complex samples like plant extracts. (C) 2001 Elsevier Science BN. All rights reserved.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据