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Induced pH-dependent shift by local surface plasmon resonance in functionalized gold nanorods.

ABSTRACT: Localized surface plasmon resonance (LSPR) spectroscopy of metallic nanoparticles is a powerful tool for chemical and biological sensing experiments. In this study, we observed LSPR shifts of 11-mercaptoundecanoic acid modified gold nanorods (GNR-MUA) for the pH range of 6.41 to 8.88. We proposed a mechanism involving changes of the dipole moment after protonation/deprotonation carboxylic groups of 11-mercaptoundecanoic acid (MUA) which plays an important role by modulating LSPR around the functionalized GNR. Such a stable and easily prepared GNR-MUA has potential to become one of the most efficient and promising pH nanosensors to study intra- or extra-cellular pH in a wide range of chemical or biological systems.

SUBMITTER: Toh YR

PROVIDER: S-EPMC3599965 | biostudies-literature | 2013 Feb

REPOSITORIES: biostudies-literature

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Induced pH-dependent shift by local surface plasmon resonance in functionalized gold nanorods.

Toh Yon-Rui YR Yu Pyng P Wen Xiaoming X Tang Jau J Hsieh Tao-Shih TS

Nanoscale research letters 20130222 1

Localized surface plasmon resonance (LSPR) spectroscopy of metallic nanoparticles is a powerful tool for chemical and biological sensing experiments. In this study, we observed LSPR shifts of 11-mercaptoundecanoic acid modified gold nanorods (GNR-MUA) for the pH range of 6.41 to 8.88. We proposed a mechanism involving changes of the dipole moment after protonation/deprotonation carboxylic groups of 11-mercaptoundecanoic acid (MUA) which plays an important role by modulating LSPR around the funct ...[more]

PMID: 23432999

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