Jump to main content
Jump to site search

Issue 28, 2008
Previous Article Next Article

Chemically bound gold nanoparticle arrays on silicon: assembly, properties and SERS study of protein interactions

Author affiliations

Abstract

A highly reproducible and facile method for formation of ordered 2 dimensional arrays of CTAB protected 50 nm gold nanoparticles bonded to silicon wafers is described. The silicon wafers have been chemically modified with long-chain silanes terminated with thiol that penetrate the CTAB bilayer and chemically bind to the underlying gold nanoparticle. The silicon wafer provides a reproducibly smooth, chemically functionalizable and non-fluorescent substrate with a silicon phonon mode which may provide a convenient internal frequency and intensity calibration for vibrational spectroscopy. The CTAB bilayer provides a potentially biomimetic environment for analyte, yet allows a sufficiently small nanoparticle separation to achieve a significant electric field enhancement. The arrays have been characterized using SEM and Raman spectroscopy. These studies reveal that the reproducibility of the arrays is excellent both between batches (<10% RSD) and across a single batch (<5% RSD). The arrays also exhibit good stability, and the effect of temperature on the arrays was also investigated. The interaction of protein and amino acid with the nanoparticle arrays was investigated using Raman microscopy to investigate their potential in bio-SERS spectroscopy. Raman of phenylalanine and the protein bovine pancreatic trypsin inhibitor, BPTI were studied using 785 nm excitation, coincident with the surface plasmon absorbance of the array. The arrays exhibit SERS enhancements of the order of 2.6 × 104 for phenylalanine, the standard deviation on the relative intensity of the 1555 cm−1 mode of phenylalanine is less than 10% for 100 randomly distributed locations across a single substrate and less than 20% between different substrates. Significantly, comparisons of the Raman spectra of the protein and phenylalanine in solution and immobilized on the nanoparticle arrays indicates that the protein is non-randomly orientated on the arrays. Selective SERS enhancements suggest that aromatic residues penetrate through the bilayer inducing conformational changes in the protein.

Graphical abstract: Chemically bound gold nanoparticle arrays on silicon: assembly, properties and SERS study of protein interactions

Back to tab navigation

Supplementary files

Article information


Submitted
20 Feb 2008
Accepted
23 Apr 2008
First published
05 Jun 2008

Phys. Chem. Chem. Phys., 2008,10, 4172-4180
Article type
Paper

Chemically bound gold nanoparticle arrays on silicon: assembly, properties and SERS study of protein interactions

A. Kaminska, O. Inya-Agha, R. J. Forster and T. E. Keyes, Phys. Chem. Chem. Phys., 2008, 10, 4172 DOI: 10.1039/B803007C

To request permission to reproduce material from this article, please go to the Copyright Clearance Center request page.

If you are an author contributing to an RSC publication, you do not need to request permission provided correct acknowledgement is given.

If you are the author of this article, you do not need to request permission to reproduce figures and diagrams provided correct acknowledgement is given. If you want to reproduce the whole article in a third-party publication (excluding your thesis/dissertation for which permission is not required) please go to the Copyright Clearance Center request page.

Read more about how to correctly acknowledge RSC content.


Social activity

Search articles by author

Spotlight

Advertisements