Effect of plasticizing and crosslinking at room temperature on microstructure replication using soft lithography on zein films

This study examined various zein film formulations to improve the properties for a Surface Enhanced Raman Spectroscopy (SERS) sensor application. Both oleic acid (OA) plasticizer and glutaraldehyde (GDA) crosslinker were simultaneously incorporated in the films to heighten particular mechanical and surface properties and enhance fidelity of transfer of micro/nano structures. It was found that both GDA and OA concentrations played a significant role in the overall properties of the film to make an effective SERS substrate. The formulation with the best fidelity of transfer during micro/nano lithography was found to be the one containing 0.8 OA with 4% GDA. SERS measurements proved that better nanostructure fidelity enhances the intensity of the Raman signal.