A novel high-throughput, high-resolution platform for electrophysiology is presented as the foundation of a new generation of brain-machine interfaces. Scientists and engineers have pursued large scale neural sensing for decades; however, physical limitations associated with electrical (electrode-based) field recordings hinder advances in both field of view and spatial resolution. Electrochromic plasmonics (electro-plasmonics) has recently emerged as a novel extracellular method for label-free optical electrophysiological sensing. However, initial demonstrations were limited to dark field measurements, which are not suitable for large area imaging applications. In this thesis, I report an important advancement in electro-plasmonic sensing techniques that utilizes nanohole-based devices and extraordinary light transmission effect. A bright-field configuration based electro-plasmonic nanohole arrays yields an extremely sensitive transducer of electric fields. Furthermore, these electro-plasmonic “nanoelectrodes” allow sub-millisecond temporal resolution without cross talk toneighboring nanoelectrodes as demonstrated in controlled experiments. Upon demonstrating the operation of this new configuration, the device was successfully used for large scale electrophysiological imaging of cardiomyocytes in vitro. Subsequently, I discuss electro-plasmonic nanoshell antennas as in vivo probes for detecting electrogenic cell activity in live animals with high-resolution. The sensitivity of these devices allows diffraction-limited resolution measurement without photobleaching and phototoxicity issues that typically plague genetically incorporated fluorescence reporters.

Biosensor technologies have enormous potential in the field of biomedical diagnostics. Despite this, certain barriers have prevented the widespread application of existing biodiagnostic technologies. The limitations include the requirements of high-end, expensive, and complicated laboratory instruments, as well as the lengthy laboratory procedures that may cause error on the part of the user. I have developed an Automated Portable Detection Platform for Point of Care Diagnostics to overcome these limitations. This platform includes a custom microfluidic Lab-On-Chip (LOC) device capable of performing point-of-care diagnostics, which will be demonstrated by performing enzyme-linked immunoassay, ELISA, tests. Using a low-cost pump and valves helped create a pneumatic system for a contactless flow between solutions in a microfluidic LOC device. The platform is relatively inexpensive and much more compact than other equipment that can be used to conduct similar tests. The automation is done via a user-friendly interface which could be accessed with a PC or Raspberry Pi microcomputer; here, a custom script may be entered to perform different functions and tests. This Automated Portable Detection Platform will be described in detail in this thesis, including its reliability and stability for precision control over the fluidic flow. In addition, data was collected and will be presented to demonstrate the abilities of this platform. Overall, this thesis will cover a significant step forward toward the adaptation of widespread point-of-care testing platforms in different clinical settings.