PYTHIA Project Realizes First All-Si Truly Integrated Mach-Zehnder Biosensor Arrays for Label-free Detection Schemes

PYTHIA project aims at the development of an innovative optoelectronic biochip for the early diagnosis of human diseases through label-free multi-analyte detection. The basic optoelectronic transducer consists of a VIS-NIR light source and an interferometric waveguide all monolithically integrated on a single Si chip. The transducer's ultimate integration level allows for the development of arrays consisting of individually functionalized interferometers coupled to their excitation source, and converging to a common detector for multiplexed operation. Encapsulation with a microfluidic system allows for the easy delivery of samples, while boarding on a disposable cartridge ensures the facile contact with the measuring apparatus. Preliminary, not-fully optimized biochips tested with model assays easily detected the binding ofstreptavidin in the pM-range, competing with the state-of-the-art label-free biosensors. The final system will be capable of simultaneous multi-analyte detection, real-time reaction monitoring and data processing, requiring minimal sample volumes and a few minutes of operation. (0 refs.)