对比三种纳米金的催化活性.pdfVIP

DOI: 10.1002/cphc.201100906 Comparison of the Peroxidase-Like Activity of Unmodified, Amino-Modified, and Citrate-Capped Gold Nanoparticles Sheng Wang, Wei Chen,* Ai-Lin Liu, Lei Hong, Hao-Hua Deng, and Xin-Hua Lin*[a] The origin of the peroxidase-like activity of gold nanoparticles buting factor to the observed peroxidase-like activity. The dif- and the impact of surface modification are studied. Further- ferent catalytic activities of amino-modified and citrate-capped more, some influencing factors, such as fabrication process, gold nanoparticles toward 3,3’,5,5’-tetramethylbenzidine (TMB) redox property of the modifier, and charge property of the and 2,2’-azino-bis(3-ethylbenzothiazoline-6-sulfonic acid) di- substrate, are investigated. Compared to amino-modified or ammonium salt (ABTS) show that the charge characteristics of citrate-capped gold nanoparticles, unmodified gold nanoparti- the nanoparticles and the substrate also play an important role cles show significantly higher catalytic activity toward peroxi- in the catalytic reactions. dase substrates, that is, the superficial gold atoms are a contri- 1. Introduction Recently, increasing attention has been paid to nanoscale per- lysts in the liquid phase may be a series of chemiluminescence oxidase mimetics and their potential applications, since the reactions.[39–41] Recently, Jv et al. made the surprising discovery discovery that iron oxide magnetic nanoparticles (NPs) have in- that cysteamine-modified positively charged gold nanoparti- trinsic enzyme-mimetic activity similar to that of natural peroxi- cles and citrate-capped negatively charged gold nanoparticles dases.[1] FeS nanosheets,[2] graphene oxide,[3] bimetallic alloy