Biosensors based on nanostructured films for earlier diagnostic of cancer

Abstract

In this proposal we will develop an integrated device for earlier cancer detection based on Surface Plasmon Resonance. The biosensors will be used to monitor molecular interactions close to the gold surface modified with nanostructures. For proof of concept, the interaction between two biomolecules with high bioaffinity will be used (biotin and streptavidin). The antibodies will be immobilized by different approaches, including single step immobilization (covalent binding) and multiple step immobilization (through bioaffinity interactions). For both procedures, the first step will consist of gold surface modification with a monolayer of thiolated molecules which binds strongly to gold. The biding of molecules on the gold surface will be monitored through changes in refractive index close to the surface by collecting transmission spectra using an UV-Vis spectrophotometer. Antibodies will be immobilized on different spots of the gold surface by using microchannels. This approach allows the immobilization of different antibodies, such as prostate, pancreatic and breast cancer, on the same platform. At the last step, antigens will be delivered on the sensor by using the same microfluidic channels.