Nanoplasmonic multifunctionalization of glycidyl methacrylate hydrogel membranes for adsorption-based Chemical Sensors with Enhanced Selectivity

Abstract

Affinity-based devices utilizing plasmonic effects belong to the most sensitive chemical sensors. A membrane having a form which coincides with the distribution of surface electromagnetic waves coupled with collective oscillations of electron gas in the conductive part of the sensor represents an important building block for plasmonics. A way to boost selectivity of a plasmonic sensor is to functionalize such membrane and either to apply it on the sensor surface or even to use it as a stand-alone platform for sensing. In this work we considered a possibility to prepare multifunctional membranes for plasmonic sensing. In our experiments selectivity enhancement was achieved through the use of glycidyl methacrylate whose epoxy group is readily converted to a desired affinity group (e.g. amine, thiol, pyridine, dithiocarbamate) to preferently capture a targeted species. Further plasmonic functionalization was obtained by forming a thin hydrogel film through copolymerization of glycidyl methacrylate with mono- and multi-functional methacrylates and then incorporating silver nanoparticles within these nanocomposites. These plasmonic nanoparticles were produced either photochemically or by chemical reduction. Different schemes for plasmonic sensor selectivity enhancement using multifunctionalized glycidyl methacrylate membranes are considered.