A nanorod polymer micro-array formed by micro-contact printing

In previous work, we demonstrate a simple approach to creating a plasmonic polymer. Reflecting upon the need for greater spot density while still maintaining the objective of low cost analysis, the next generation of device is described where density up to 24000 sensing spots is achievable. A localized surface plasmon micro-array is described formed by single or multiple deposition of a nanorod plasmonic polymer by micro-contact printing. The structure of the polymer can be made micro-porous and thickness can be controlled by a cyclical deposition and rapid heat cure protocol. The consistency of feature deposition is assessed. The resulting micro-structure provides a large surface area for immobilization of biomolecules for assay development. Dark-field analysis of the polymer demonstrates complex microstructure and intense Mie Scattering as expected from gold nanorods. Using fluorescence confocal analysis images of the polymer demonstrates two independent photo-luminescent emission spectra. The two independent emission spectra are linked to the positions of the localized surface plasmons of the nanorods, using a pump source of 543nm excites the transverse plasmon (peak at 550nm)and it's commensurate emission, but doesn't excite the longer emission around 700nm that is linked to the longitudinal Plasmon around 737nm. The different emissions are demonstrated in the illumination of different portions of the polymer matrix under each pump source excitation. The potential for multiple spectroscopic biosensor analysis is discussed.