Voltage-Sensitive Diamond Nanosensors

In this Small Business Innovation Research program, we will develop a new class of nanosensors that are high contrast, ultrabright and fast optical voltage-indicators from diamond nanocrystals for neural activity imaging applications in vitro and in vivo. These photostable and cytocompatible diamond nanosensors will be able to monitor the bioelectric states and sub-threshold events in human cells at the nanometer scale without photo bleaching (hundreds of hours of continuous readout from a single nanosensor). Our optical detection scheme is based on the exceptional capabilities of nitrogen-vacancy (NV) color centers in diamond but does not rely on spin-based interrogation techniques commonly deployed for NV center sensing. In Phase I of this program we will conduct a feasibility study to test the viability of this new approach. To do so, we set three objectives: (1) fabrication of the nanosensors, (2) voltage sensitivity characterization in cultured neurons, and (3) theoretical and computational analysis of performance of the diamond nanosensors. In Phase II of this program we will optimize the voltage-indication performance of the diamond nanosensors, develop a scalable fabrication process, and design targeting schemes to ensure broad use of the nanosensors in the life sciences.