Gold nanoparticle films as sensitive and reusable elemental mercury sensors.

ABSTRACT: We demonstrate the utility of gold nanoparticles (AuNPs) as the basis of a stand-alone, inexpensive, and sensitive mercury monitor. Gold nanoparticles absorb visible light due to localized surface plasmon resonance (LSPR), and the absorbance changes when mercury combines with the gold nanoparticles. The sensitivity of the peak absorbance is proportional to the surface-area-to-volume ratio. We chose 5 nm spheres because they have the largest surface-area-to-volume ratio while still having a peak absorption in the visible range. The adsorption of 15 atoms of Hg causes a 1 nm shift in the LSPR wavelength of these particles. Assembled into a film using the Langmuir-Blodgett method, the AuNP LSPR can be tracked with a simple UV-vis spectrometer. The rate of shift in the peak absorbance is linea

SUBMITTER: James JZ 

PROVIDER: S-EPMC3446241 | biostudies-literature | 2012 Sep

REPOSITORIES: biostudies-literature