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Enhancement of Paramagnetic Relaxation by Photoexcited Gold Nanorods.

ABSTRACT: Electron spin resonance (ESR) spectroscopy was used to investigate the switchable, light-dependent effects of gold nanorods (GNRs) on paramagnetic properties of nitroxide spin probes. The photoexcited GNRs enhanced the spin-spin and spin-lattice relaxations of nitroxide spin probes. It was shown that molecular oxygen plays the key role in this process. Our results demonstrate that ESR is a powerful tool for investigating the events following photoexcitation of GNRs. The novel light-controlled effects observed for GNRs on paramagnetic properties and activities of surrounding molecules have a number of significant applications where oxygen sensing and oxygen activity is important.

SUBMITTER: Wen T

PROVIDER: S-EPMC4829829 | biostudies-other | 2016 Apr

REPOSITORIES: biostudies-other

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Enhancement of Paramagnetic Relaxation by Photoexcited Gold Nanorods.

Wen Tao T Wamer Wayne G WG Subczynski Witold K WK Hou Shuai S Wu Xiaochun X Yin Jun-Jie JJ

Scientific reports 20160413

Electron spin resonance (ESR) spectroscopy was used to investigate the switchable, light-dependent effects of gold nanorods (GNRs) on paramagnetic properties of nitroxide spin probes. The photoexcited GNRs enhanced the spin-spin and spin-lattice relaxations of nitroxide spin probes. It was shown that molecular oxygen plays the key role in this process. Our results demonstrate that ESR is a powerful tool for investigating the events following photoexcitation of GNRs. The novel light-controlled ef ...[more]

PMID: 27071507

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