1. Preconcentrated Gold Nanoparticle
as a Surface Enhanced Raman Scattering Substrate
in a Microfluidic Chip
Kwang Bok Kim1, Ji-Hyung Han2, Hyoungseon Choi1, Taek Dong Chung2* and Hee Chan Kim3*
1Interdisciplinary Program, Bioengineering Major, Graduate School of Seoul National University, Seoul, Korea
2Department of Chemistry, Seoul National University, Seoul, Korea
3Department of Biomedical Engineering, College of Medicine and Institute of Medical & Biological Engineering
, Medical Research Center, Seoul National University, Seoul, Korea
B. Working principle
(1) Anion preconcentration
C. Experiments
Surface-enhanced Raman Scattering (SERS)
SERS on a Chip using preconcentrated gold
nanoparticles
Preconcentration Method
: Electrokinetic trapping
- Ion-depletion
- Extract cations through the charge selective
polymer
(poly-2-acrylamido-2-methyl-1-propanesulfonic
acid, pAMPSA)
Samples (SERS analytes)
- 4-aminobenzoic acid (4-ABA)
- pyridine
- 4-mercaptobenzoic acid (4-MBA)
- Neurotransmitter (Histamine)
SERS signal obtained every 10 seconds
(a) Cation extraction
(b) Ion depletion
A. SERS on a Chip
(c) Anion preconcentration
(2) Anionic gold nanoparticle preconcentration
and SERS analysis
The gold nanoparticles have negative zeta
potential at pH values over 5.
The proposed system can also preconcentrate
the anionic metal nanoparticles such as a gold
nanoparticle.
Optimum Power
- V1 : 20 V
- V2 : 5 V
Reversible preconcentrator
Not necessary to fabricate and clean the SERS-
active nano structure.
The preconcentrated gold nanoparticles can be
uses as SERS-active substrate.
Reduce the sample and reagent volume.
This method may provide new approach that
research about ‘hot-spot’ of SERS.
Further research, SERS on a chip system will
propose the small-sized SERS device.
Glass to glass microfluidic chip
- Width : 60 um , Height : 30 um
Electrode : Platinum
Laser : He-Ne 633 nm
Raman spectroscopic system
Power : DC-2 channel
Gold nanoparticle
- 20 nm (dia.) in 10 mM PB
- PB (Phospate Buffer)
*This work was supported by the National Research Foundation of Korea(NRF) grant funded by the Korea government(MEST) (No ).