Fabrication of Gold Nanoparticles/Graphene-PDDA Nanohybrids for Bio-detection by SERS Nanotechnology

• Published in: Nanoscale research letters Vol. 10; no. 1; p. 397
• Main Authors: Mevold, Andreas H H, Hsu, Wei-Wu, Hardiansyah, Andri, Huang, Li-Ying, Yang, Ming-Chien, Liu, Ting-Yu, Chan, Tzu-Yi, Wang, Kuan-Syun, Su, Yu-An, Jeng, Ru-Jong, Wang, Juen-Kai, Wang, Yuh-Lin
• Format: Journal Article
• Language: English
• Published: New York Springer US 01.12.2015; Springer Nature B.V
• Subjects: Adenines; Bacteria; Chemistry and Materials Science; EMN Meeting; Gold; Graphene; Materials Science; Molecular Medicine; Nano Express; Nanochemistry; Nanoscale Science and Technology; Nanostructure; Nanotechnology; Nanotechnology and Microengineering; Raman scattering; Transmission electron microscopy; Zeta potential; Surface-enhanced Raman scattering; Graphene; Gold nanoparticles; Bio-detection
• ISSN: 1931-7573; 1556-276X
• DOI: 10.1186/s11671-015-1101-2

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.