Heydari, Esmaeil and Mabbott, Samuel and Thompson, David and Graham, Duncan and Cooper, Jonathan M. and Clark, Alasdair W. (2016) Engineering molecularly-active nanoplasmonic surfaces for DNA detection via colorimetry and Raman scattering. In: Nanoscale Imaging, Sensing, and Actuation for Biomedical

We report a novel nanophotonic biosensor surface capable of both colorimetric detection and Raman-scattered detection of DNA infection markers at extreme sensitivities. Combining direct-write lithography, dip-pen nanolithography based DNA patterning, and molecular self-assembly, we create molecularly-active plasmonic nanostructures onto which metallic nanoparticles are located via DNA-hybridization. Arraying these structures enables optical surfaces that change state when contacted by specific DNA sequences; shifting the surface color while simultaneously generating strong Raman-scattering signals. Patterning the DNA markers onto the plasmonic surface as micro-scale symbols results in easily identifiable color shifts, making this technique applicable to multiplexed lab-on-a-chip and point-of-care diagnostic applications.