Heterogeneous integration of polymer porous photonic bandgap structure with xerogel based biochemical sensors

We report the heterogeneous integration of a multifunctional sensor based on polymer porous photonic bandgap (P ³BG) structure and xerogel based luminescence sensor technology. The P ³BG structure was fabricated using holographic interferometry. Initially, holographic interferometry of a photo-activated prepolymer syrup that included a volatile solvent as well as monomer, photoinitiator, and co-initiator was used to initiate photopolymerization. Subsequent UV curing resulted in well defined lamellae of the polymer separated by porous polymer regions that created a high quality photonic bandgap structure. The resulting P ³BG structure was then integrated with the xerogel based luminescence element to produce a luminescence sensor with a selective narrow band reflector. The prototype xerogel based luminescence sensor element consisted of an O ₂ sensing material based on spin coated tetraethylorthosilane (TEOS) composite xerogel films containing tris (4,7-diphenyl-1,10-phenanthroline) ruthenium (II) ([Ru(dpp) ₃] ²⁺) luminophore. We demonstrated enhancement of the signal-to-noise ratio (SNR) of this integrated multifunctional sensor while maintaining the same sensitivity to O ₂ sensing of the xerogel based element. The resulting advantages and enhanced SNR of this integrated sensor will provide a template for other luminescence based assays to support highly sensitive and cost-effective sensor systems for biomedical applications.