首页 | 本学科首页   官方微博 | 高级检索  
     检索      


Detection of flavonoids and assay for their antioxidant activity based on enlargement of gold nanoparticles
Authors:Jing Wang  Nandi Zhou  Zhiqiang Zhu  Junyi Huang  Genxi Li
Institution:(1) Department of Biochemistry and National Key Laboratory of Pharmaceutical Biotechnology, Nanjing University, Nanjing, 210093, China;(2) School of Life Science and Shanghai Key Laboratory of Bio-Energy Crops, Shanghai University, Shanghai, 200444, China
Abstract:We report our findings that natural flavonoids such as quercetin, daizeol and puerarin can act as reductants for the enlargement of gold nanoparticles (Au-NPs). Consequently, the UV–vis spectra of a solution containing Au-NPs will be gradually changed, and the molecules of the natural herbs can be detected by making use of changes in the UV–visible spectra. Furthermore, we have prepared a self-assembled monolayer modified electrode by modifying cysteamine on a gold substrate electrode, which is further modified by some Au-NP seeds. When the modified electrode is immersed in a solution containing flavonoids and tetrachloroauric acid as a gold source for the growth of the Au-NP seeds, with the increase of the concentration of flavonoids, the Au-NP seeds on the surface of the modified electrode can be enlarged to varying degrees. As a result, the peak currents in the corresponding cyclic voltammograms are inversely decreased, and simultaneously the peak separation is increased. Therefore, an electrochemical method to detect flavonoids is also proposed. Compared with the optical detection method, the electrochemical method has an extraordinarily lower detection limit and a significantly extended detection range. Moreover, the optical and electrochemical experimental results can be also used to assay and compare the relative antioxidant activities of the flavonoids. MediaObjects/216_2007_1295_Figa_HTML.gif Figure Enlargement of Au nanoparticles by flavonoids at cysteamine modified electrode
Keywords:Gold nanoparticles  Flavonoid  Antioxidant  Detection
本文献已被 PubMed SpringerLink 等数据库收录!
设为首页 | 免责声明 | 关于勤云 | 加入收藏

Copyright©北京勤云科技发展有限公司  京ICP备09084417号