Loading…
Cost-Effective Plasmonic Platforms: Glass Capillaries Decorated with Ag@SiO 2 Nanoparticles on Inner Walls as SERS Substrates
A cost-effective method for the fabrication of a glass capillary based plasmonic platform for the selective detection and identification of analytes of importance in health, environment, and safety is demonstrated. This was achieved by coating Ag@SiO nanoparticles (Ag ∼ 60 nm) having silica shell of...
Saved in:
Published in: | ACS applied materials & interfaces 2017-06, Vol.9 (23), p.19470-19477 |
---|---|
Main Authors: | , , |
Format: | Article |
Language: | English |
Citations: | Items that this one cites Items that cite this one |
Online Access: | Get full text |
Tags: |
Add Tag
No Tags, Be the first to tag this record!
|
Summary: | A cost-effective method for the fabrication of a glass capillary based plasmonic platform for the selective detection and identification of analytes of importance in health, environment, and safety is demonstrated. This was achieved by coating Ag@SiO
nanoparticles (Ag ∼ 60 nm) having silica shell of varying thickness (∼2 and ∼25 nm) on the inside walls of glass capillaries, over 2 cm in length, with uniform coverage. It was found that the particle density on the surface plays a decisive role on the enhancement of Raman signals. Multiple hot spots, which are essentially junctions of amplified electric field, were generated when ∼30 Ag@SiO
particles/μm
were bound onto the walls of glass capillaries. The pores of the silica shell allow the localization of analyte molecules to the vicinity of hot spots resulting in signal enhancements of the order of 10
(using pyrene as analyte; excitation wavelength, 632.8 nm). The applicability of Ag@SiO
coated capillaries for the detection of a wide range of molecules has been explored, by taking representative examples of polyaromatic hydrocarbons (pyrene), amino acids (tryptophan), proteins (bovine serum albumin), and explosives (trinitrotoluene). By increasing the thickness of the silica shell of Ag@SiO
nanoparticles, an effective filtration cum detection method has been developed for the selective identification of small molecules such as amino acids, without the interference of large proteins. |
---|---|
ISSN: | 1944-8244 1944-8252 |
DOI: | 10.1021/acsami.6b12478 |