Highly integrated biophotonics towards all-organic lab-on-chip systems

Abstract

For sensing with lab-on-chip systems, the use of highly integrated photonic components is a key ingredient for high sensitivity and short response time. Here, we present the efficient integration of organic semiconductor distributed feedback lasers based on Alq 3 :DCM and deep ultraviolet induced waveguides into a Poly(methyl methacrylate) (PMMA) substrate. The optimized coupling of laser light from the organic semiconductor lasers into the waveguides is discussed. On-chip coupling of laser light at 645 nm to waveguides is demonstrated. Utilizing mass production technologies and simple processes with only a few different materials paves the way for low-cost all-organic chips. In particular, a specific sensing concept is introduced: deep ultraviolet induced waveguides and nanostructured phospholipid gratings, which are bottom-up assembled using Dip-Pen Nanolithography, are combined to form a grating coupler with a grating period of 700 nm. Light of different wavelength is decoupled under different angles by the grating coupler to demonstrate its functional capability. Biosensing with this device is discussed based on a model system.