Tunable, spatially addressable functionalization strategies for micro/nano scale, multi-analyte biosensors

Physiological sensing is inherently a multi-scale problem involving measurements of multiple analytes, spanning a broad range of spatial and temporal scales from either single cells or complex cell networks. Addressing multiple scales requires novel high throughput sensing paradigms capable of multiplexed, multi-modal sensing with high spatial and temporal resolution. In recent years, novel nanomaterials and fabrication techniques have enabled a new generation of electrical and optical sensing elements that have significantly enhanced sensor sensitivity and temporal resolution. However, biofunctionalization of these sensing elements still rely on relatively simple drop-coating or dip-coating methods to achieve coupling with analyte-specific transducers. Use of such passive functionalization methods limits the spatial resolution, precludes multiplexing and restricts use in high throughput schemes. We have developed novel electrochemical and optical sensor functionalization strategies that utilize the sensing element as an active component in the functionalization process. In both modalities the sensing element is used to actively direct polymerization of selected monomers to produce polymer matrices that entrap the analyte-specific transducer within the active zone of the sensor element. Electrochemically and optically activated monomers are used to achieve tunable doping of transducer molecules such as enzymes, organic dyes and fluorescent sensor proteins at resolutions limited only by the size and spacing of the fabricated sensing element. These methods represent a significant advancement towards multiplexed, multimodal sensing of a wide range of analytes at high spatial and temporal resolution