Spectroscopic ellipsometry investigation of gold nanoparticles embedded in PDMS for bio-sensing applications

In this work, sensing capability of gold nanoparticles embedded in polydimethylsiloxane (PDMS) based localized surface plasmon resonance (LSPR) was investigated. A simple, stable, and low-cost sensor is presented. Various samples at different initial thickness of gold films were prepared and used to investigate the thickness effect on their optical properties. For optical characterization, a UV-Vis spectrophotometer was used in order to measure absorption spectra of the prepared samples. The UV-Vis spectrophotometer results showed that thicker initial gold film produces a wider and red shift absorption spectrum compared to the thinner gold film. Besides, the spectroscopic ellipsometry was used to investigate the sensitivity based LSPR of the proposed structure. Hence, the proposed sensor could be good as a cost-effective scheme for biosensing applications.