Wednesday, December 4, 2024
12/4/2024
Summary Single-molecule fluorescent live-cell imaging impacts translational biology by correlating individual protein function with biological outcomes. Fluorescent nanodiamond sensors are capable of reporting on local electromagnetic fields, free radicals, temperature, pH, and rotational orientation through nitrogen-vacancy color centers. At molecular-level sizes (10-20 nm), however, these NV- emitters are destabilized to become inactive and thus are not useable. In this proposal, we produce ultrasmall NDNV sensors with stabilized NV- by fluorination and nitridation surface treatment as demonstrated by our preliminary results and guided by theory. We use a plasma generated at atmospheric pressure through a dielectric barrier discharge to generate reactive species that lead to surface chemical modifications at room temperature. A prototype reactor demonstrated successful treatment of NDNV at sizes above ~50 nm. To develop ultrasmall nanodiamond-based sensors, diamond nanomaterials from 10-40 nm size range will be functionalized by fluorination or nitridation to stabilize NV-. In both cases, the excited state populations of the feedstock gases will be controlled by gas composition, flow rate, and base pressure in combination with the plasma parameters. Chemical functionalization will be verified and then correlated with optical properties which represent NV- content. Optimized candidates will then be assessed to demonstrate changes in NV- content and quantum-relevant characteristics (T1 and T2). Because the surfaces generated will be novel, cell viability screening to confirm that particles are consistent with nanodiamond’s well-demonstrated biocompatibility will be also performed. To meet the growing demand as predicted by commercialization estimates, scaled-production (grams-quantity per day) of functionalized nanodiamond particles could be achievable by the end of phase II if successful. These ultrasmall NDNV quantum sensors are expected to impact our understanding of disease and enable new modalities for drug and biomarker discovery.
HHS’ Tracking Accountability in Government Grants System (TAGGS) website provides access to detailed descriptions of grants, loans, aggregated direct payments and other types of financial assistance awarded by the HHS Operating Divisions (OPDIVs) and the Office of the Secretary Staff Divisions (STAFFDIVs).
