Table of Contents
ISRN Nanomaterials
Volume 2012 (2012), Article ID 659043, 9 pages
http://dx.doi.org/10.5402/2012/659043
Research Article

Synthesis and Characterization of Gold Nanoparticles with Plasmon Absorbance Wavelength Tunable from Visible to Near Infrared Region

1Department of Biomedical Engineering, University of Texas at San Antonio, San Antonio, TX 78249, USA
2Department of Medical Technology, Yancheng Health Vocational and Technical College, Jiangsu, Yancheng 224006, China

Received 31 May 2012; Accepted 26 June 2012

Academic Editors: G. Dzhardimalieva, G.-H. Kim, and G. Skordaris

Copyright © 2012 Weihong Shi et al. This is an open access article distributed under the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.

Abstract

Gold nanorods with localized surface plasmon resonance (LSPR) can be chemically synthesized. We systematically investigated the effects of reaction parameters and centrifugation on the fine tuning of the rod dimension in scale-up production (80–100 mL). Nanorods of absorption bands from 600–1050 nm were fabricated with precise control of the aspect ratio (AR) from 1.5 to 8.9. Although all chemicals are important in directing the nanostructure, silver ion concentration and seed/Au3+ ratio were the most effective variations to adjust the absorption wavelength. With a single surfactant under the influence of silver nitrate, short nanorods up to AR of 5 were synthesized with corresponding maximum absorption wavelength at 902 nm. To achieve higher aspect ratio with absorption band beyond 1,000 nm, two-surfactant growth solution was sought to further elongate the rod length. Centrifugation speed and times were found to exert significant influences on the final rod dimension, which is important during the purification process. In a relatively large quantity nanorod synthesis, even distribution and sufficient mixing of chemical ingredients play an essential role in determining the yield, uniformity, and stability of the final nanorod formation.