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Iodide-Mediated Rapid and Sensitive Surface Etching of Gold Nanostars for Biosensing.

ABSTRACT: Iodide-mediated surface etching can tailor the surface plasmon resonance of gold nanostars through etching of the high-energy facets of the nanoparticle protrusions in a rapid and sensitive way. By exploring the underlying mechanisms of this etching and the key parameters influencing it (such as iodide, oxygen, pH, and temperature), we show its potential in a sensitive biosensing system. Horseradish peroxidase-catalyzed oxidation of iodide enables control of the etching of gold nanostars to spherical gold nanoparticles, where the resulting spectral shift in the surface plasmon resonance yields a distinct color change of the solution. We further develop this enzyme-modulated surface etching of gold nanostars into a versatile platform for plasmonic immunoassays, where a high sensitivity is possible by signal amplification via magnetic beads and click chemistry.

SUBMITTER: Xianyu Y

PROVIDER: S-EPMC8251757 | biostudies-literature |

REPOSITORIES: biostudies-literature

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