| Author(s): |
Darwin R. Reyes-Hernandez; Geraldine I. Mijares; Brian J. Nablo; Kimberly A. Briggman; Michael Gaitan; |
| Title: |
Trapping and Release of Citrate-Capped Gold Nanoparticles |
| Published: |
August 01, 2011 |
| Abstract: |
An electrical method to trap and release charged gold nanoparticles on and from the surface of alkanethiol self-assembled-monolayer (SAM) modified gold electrodes is presented. Gold nanoparticle (GNP) coated electrodes were formed by immersing amine-terminated SAM-modified gold electrodes into a solution of negatively-charged citrate-capped gold nanoparticles (GNPs). The electrostatic interactions kept the GNPs trapped on the electrode. The presence of the GNPs decreased the impedance of the SAM-modified electrode, and increased the electrochemical activity at at the electrode as shown through cyclic voltammetry. The application of a subsequent negative bias initiated a partial release of the gold nanoparticles. Impedance spectroscopy, cyclic voltammetry, UV-Vis spectrophotometry and AFM imaging were used to monitor the attraction and release of gold nanoparticles to and from the SAM-modified gold electrodes. This work describes a trapping and release method for citrate-capped gold nanoparticles that could find use in applications such as nanotoxicity studies and other microfluidic assays, and functionalization of gold nanoparticles. |
| Citation: |
Applied Surface Science |
| Volume: |
257 |
| Issue: |
20 |
| Pages: |
5 pp. |
| Keywords: |
gold nanoparticles; electrostatic interactions; self-assembled monolayers |
| Research Areas: |
Nanotechnology |
| PDF version: |
 Click here to retrieve PDF version of paper (954KB) |
