%0 Conference Paper %B The 15th International Conference on Miniaturized Systems for Chemistry and Life Sciences %D 2011 %T Label-Free Biosensing Using Cascaded Silicon-on-Insulator Micro-Racetrack Resonators Integrated With PDMS Microfluidic Channels %A Flueckiger, Jonas %A Grist, Samantha %A Ouellet, Eric %A Chrostowski, Lukas %A Cheung, Karen %C Seattle, Washington, USA %X This paper demonstrates a label-free biosensing platform using Silicon-On-Insulator (SOI) micro-racetrack resonators, cascaded such that multiple measurements can be made using a single input and output waveguide and therefore a single detector. The devices are integrated with poly(dimethylsiloxane) microfluidic channels in order to characterize the devices? sensing properties. Both bulk refractive index sensing using glycerin/water solutions and clinically-relevant biosensing using Human Factor IX and its corresponding antibody are characterized. Bulk sensitivities of 40 nm/RIU are achieved, and the devices are able to sense both the protein attachment during functionalization and the protein-antibody binding reaction. %8 10/2011