Skip to main content
Kent Academic Repository

Synthesis, stabilization, and functionalization of silver nanoplates for biosensor applications

Guevel, X.L., Wang, F.Y., Stranik, O., Nooney, R., Gubala, V., McDonagh, C., MacCraith, B.D. (2009) Synthesis, stabilization, and functionalization of silver nanoplates for biosensor applications. Journal of Physical Chemistry C, 113 (37). pp. 16380-16386. ISSN 1932-7447. (doi:10.1021/jp904761p) (KAR id:45243)


Silver nanoplates (NPTs) were prepared by a seed-mediated growth method with different diameters (d = 25, 32, 53, and 100 nm) and with thicknesses of approximately 10 nm in all cases. As the concentration of silver seeds increased, the diameter of the nanoplates increased, resulting in an overall shift in the localized surface plasmon resonance (LSPR) band maximum from 570 to 900 nm, thus providing a novel method to tune the plasmon resonance. The LSPR was calculated from theory for both triangular and circular nanoplate geometries. In agreement with transmission electron micrographs, the model results confirmed the shape of nanoplates as being truncated prisms, intermediate between that of a prism and a disk. Because of the toxicity of the surfactant hexadecyltrimethylammonium bromide (CTAB), the stabilizing CTAB bilayer surrounding the NPT was replaced by a nontoxic alkanethiol with surfactant properties. This enabled the extraction of metal nanoparticles into deionized water or buffer for bioconjugation without aggregation. Silver nanoplates were also coated with polyelectrolyte layers using the standard layer-by-layer (LbL) method. The LSPR was found to be very sensitive to the addition of polyelectrolyte layers, with a plasmon band shift from 728 to 740 nm after adding only one monolayer (thickness ~1.5 nm). Bioconjugation of these nanoplates was achieved with the addition of a mercaptolinker containing a carboxyl group. The carboxyl groups were activated with 1-ethyl-3-(3- dimethylaminopropyl) hydrochloride (EDC)/N-hydroxysuccinimide (NHS) and conjugated to green fluorescent protein (GFP) in order to validate the potential of the NPTs for enhancement of bioassays. The fluorescence of the conjugated NPTs was 5.6-fold brighter than that of NPTs added to GFP without activation. © 2009 American Chemical Society.

Item Type: Article
DOI/Identification number: 10.1021/jp904761p
Additional information: Unmapped bibliographic data: LA - English [Field not mapped to EPrints] J2 - J. Phys. Chem. C [Field not mapped to EPrints] AD - Biomedical Diagnostics Institute, School of Physical Sciences, Dublin City University, Glasnevin, Dublin 9, Ireland [Field not mapped to EPrints] DB - Scopus [Field not mapped to EPrints]
Uncontrolled keywords: Alkanethiols, Bi-layer, Bio-conjugation, Biosensor applications, Carboxyl groups, Concentration of, Functionalizations, Green fluorescent protein, Hexadecyltrimethylammonium bromide, Layer-by-layer methods, Localized surface plasmon resonance, Metal nanoparticles, Model results, N-hydroxysuccinimide, Nano-Plate, Nanoplates, Novel methods, Plasmon band, Plasmon resonances, Polyelectrolyte layers, Seed mediated growth, Silver nanoplates, Surfactant properties, Transmission electron micrograph, Biosensors, Deionized water, Extraction, Fluorescence, Metal recovery, Monolayers, Plasmons, Polyelectrolytes, Prisms, Silver, Surface active agents, Surface plasmon resonance, Organic polymers
Divisions: Divisions > Division of Natural Sciences > Medway School of Pharmacy
Depositing User: Vladimir Gubala
Date Deposited: 14 Dec 2017 21:08 UTC
Last Modified: 16 Nov 2021 10:18 UTC
Resource URI: (The current URI for this page, for reference purposes)

University of Kent Author Information

  • Depositors only (login required):

Total unique views for this document in KAR since July 2020. For more details click on the image.