PDMS-Au/Ag Nanocomposite Films as Highly Sensitive SERS Substrates

Abstract

Polydimethylsiloxane (PDMS)–gold/silver nanoparticle composite films were synthetized in situ by using a simple method, which is based on the reduction of chloroauric acid (HAuCl4) or silver nitrate solution (AgNO3) by the PDMS membrane. A method to monitor the development of the plasmonic absorbance peak in situ (during the synthesis of the nanoparticles) is introduced in order to provide a convenient way to investigate the effect of the technological parameters on the position of the resulting peak. The resulting composite films were tested as SERS substrates at two excitation wavelengths (488 nm, 785 nm) and the preliminary results indicate that they are promising candidates for this application, with high sensitivities accompanied by cheap fabrication costs.