Enhanced radical scavenging activity by antioxidant-functionalized gold nanoparticles: a novel inspiration for development of new artificial antioxidants.
Because of its potent antioxidant function and important role in clinical treatment, alpha-tocopherol (vitamin E) is a good starting point in the development of new synthetic antioxidants with improved properties. In this paper the first example of antioxidant-functionalized gold nanoparticles, Au@Trolox, was synthesized by self-assembly of thiol ligands derived from Trolox, a vitamin E analogue, on gold nanoparticles. DPPH* (2,2-diphenyl-1-picrylhydrazyl) radical scavenging experiments revealed that the rate constant for the reaction of Au@Trolox with DPPH* was about eight times greater than that for Trolox. The product analysis showed that both the quinonoid and the diepoxide forms were possible oxidized products of the chromanol group of Au@Trolox treated with DPPH* radical. No remarkable influence was found on the antioxidant activity of Au@Trolox when the coverage rate of the antioxidant group on the surface of the gold was varied. All our results proved that the assembly of chromanol groups on gold nanoparticles could efficiently enhance the activity of the vitamin E-derived antioxidant, which presents a potential new strategy for antioxidant design with novel perspectives in potential applications.
Nie
Zhou
Z
State Key Lab for Structural Chemistry of Unstable and Stable Species, Beijing National Laboratory for Molecular Sciences, Institute of Chemistry, Chinese Academy of Sciences, Beijing 100080, China.
Liu
Ke Jian
KJ
Zhong
Chuan-Jian
CJ
Wang
Lan-Fen
LF
Yang
Ying
Y
Tian
Qiu
Q
Liu
Yang
Y
D000975:Antioxidants / Q000737:chemistry* / Q000378:metabolism; D001713:Biphenyl Compounds; D004578:Electron Spin Resonance Spectroscopy; D016166:Free Radical Scavengers / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D006046:Gold / Q000737:chemistry* / Q000378:metabolism / Q000494:pharmacology; D053768:Metal Nanoparticles / Q000737:chemistry*; D010851:Picrates / Q000737:chemistry / Q000378:metabolism; D017550:Spectroscopy, Fourier Transform Infrared; D014810:Vitamin E / Q000031:analogs & derivatives* / Q000737:chemistry / Q000378:metabolism / Q000494:pharmacology
D000975:Antioxidants; D001713:Biphenyl Compounds; D016166:Free Radical Scavengers; D010851:Picrates; D014810:Vitamin E; D006046:Gold; C004931:1,1-diphenyl-2-picrylhydrazyl