Understanding how the human brain functions is without question one of the most daunting challenges currently facing the field of neuroscience. It is only after we understand normal brain physiology that we can begin to effectively diagnose and treat brain pathologies that are a critical priority for both DOD and civilian medicine. Given the impact of post-traumatic stress disorder, traumatic brain injury and depression on warfighters and their families and the impact of such brain pathologies as multiple sclerosis, Alzheimer’s and Parkinson’s diseases, schizophrenia and epilepsy have on civilian medicine, there is clearly a critical need for a detailed understanding of the workings of the brain’s circuitry. This priority is clearly evidenced by the President’s recent announcement in March 2013 of plans for the Brain Research through Advancing Innovative Neurotechnologies (BRAIN) Initiative whose primary aim is to produce a dynamic picture of how the brain functions in real-time. However, a critical roadblock in this endeavor remains the lack of suitable nanoscale probes that are capable of targeting to the neuronal cell membrane and reporting in real-time on neuronal cell electrical activity and intercellular communication.

The goal of this program is to take advantage of the inherent properties of colloidal nanoparticles (e.g., semiconductor quantum dots, gold nanoparticles) to develop them as probes for imaging membrane potential in neurons. The advantageous properties of these nanoscale particles includes (1) their small size (comparable to the size of the plasma membrane bilayer), (2)-their photophysical and electronic properties that can be modulated in response to changes in electric field strength, and (3)-their ability to be targeted noninvasively to the neuronal cell membrane. This program will work at the intersection of biology, materials, and neuroscience to realize the next generation of voltage-sensitive nanoprobes for imaging neuronal cell communication.