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Fabrication of silica-coated gold nanorods functionalized with DNA for enhanced surface plasmon resonance imaging biosensing applications.

ABSTRACT: A novel method for preparing gold nanorods that are first coated with a thin silica film and then functionalized with single-stranded DNA (ssDNA) is presented. Coating the nanorods with 3-5 nm of silica improves their solubility and stability. Amine-modified ssDNA is attached to the silica-coated gold nanorods via a reductive amination reaction with an aldehyde trimethoxysilane monolayer. The nanorods exhibit an intense absorption band at 780 nm, and are used to enhance the sensitivity of surface plasmon resonance imaging (SPRI) measurements on DNA microarrays.

SUBMITTER: Sendroiu IE

PROVIDER: S-EPMC2756695 | biostudies-literature | 2009 Oct

REPOSITORIES: biostudies-literature

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Fabrication of silica-coated gold nanorods functionalized with DNA for enhanced surface plasmon resonance imaging biosensing applications.

Sendroiu Iuliana E IE Warner Megan E ME Corn Robert M RM

Langmuir : the ACS journal of surfaces and colloids 20091001 19

A novel method for preparing gold nanorods that are first coated with a thin silica film and then functionalized with single-stranded DNA (ssDNA) is presented. Coating the nanorods with 3-5 nm of silica improves their solubility and stability. Amine-modified ssDNA is attached to the silica-coated gold nanorods via a reductive amination reaction with an aldehyde trimethoxysilane monolayer. The nanorods exhibit an intense absorption band at 780 nm, and are used to enhance the sensitivity of surfac ...[more]

PMID: 19788208

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