All-Optical Biophotonic and Microfluidic Circuits for Photo-Thermal Applications

We propose a photonic biochip which combines optical and microfluidic channels to exploit the potential of gold nanorods (GNRs) in developing light-assisted antimicrobial therapies. The proposed chip is obtained by coupling two separately processed PolyDiMethylSiloxane (PDMS) substrates in which microfluidic channels, conveying biological fluid flow, and optical waveguides, confining near-infrared light, interact. The light activates the localized plasmonic resonance of GNRs dispersed in a film deposited on the functionalized PDMS substrates. This paper uses experimental measurements and numerical simulations based on Finite Element Method software tools to optimize the final design in terms of suitable GNRs irradiation, dimensions, aspect ratio, density, and distribution.