Fabrication of Gold Nanoparticles/Graphene-PDDA Nanohybrids for Bio-detection by SERS Nanotechnology
Journal
Nanoscale Research Letters
Journal Volume
10
Journal Issue
1
Pages
1-7
Date Issued
2015
Author(s)
Mevold, A.H.H.
Hsu, W.-W.
Hardiansyah, A.
Huang, L.-Y.
Yang, M.-C.
Liu, T.-Y.
Chan, T.-Y.
Wang, K.-S.
Su, Y.-A.
Jeng, R.-J.
Abstract
In this research, graphene nanosheets were functionalized with cationic poly (diallyldimethylammonium chloride) (PDDA) and citrate-capped gold nanoparticles (AuNPs) for surface-enhanced Raman scattering (SERS) bio-detection application. AuNPs were synthesized by the traditional citrate thermal reduction method and then adsorbed onto graphene-PDDA nanohybrid sheets with electrostatic interaction. The nanohybrids were subject to characterization including X-ray diffraction (XRD), transmission electron microscopy (TEM), zeta potential, and X-ray photoelectron spectroscopy (XPS). The results showed that the diameter of AuNPs is about 15-20 nm immobilized on the graphene-PDDA sheets, and the zeta potential of various AuNPs/graphene-PDDA ratio is 7.7-38.4 mV. Furthermore, the resulting nanohybrids of AuNPs/graphene-PDDA were used for SERS detection of small molecules (adenine) and microorganisms (Staphylococcus aureus), by varying the ratios between AuNPs and graphene-PDDA. AuNPs/graphene-PDDA in the ratio of AuNPs/graphene-PDDA = 4:1 exhibited the strongest SERS signal in SERS detection of adenine and S. aureus. Thus, it is promising in the application of rapid and label-free bio-detection of bacteria or tumor cells.
Publisher
Springer New York LLC
Type
journal article