PROJECT SUMMARY/ABSTRACT Nitric oxide (NO) is a key signaling molecule in biological systems, but it is poorly understood due to a lack of temporal and spatial sensors that measure NO. A direct, fast and accurate sensor for measuring NO would be of immense value to ongoing and future research. Single walled carbon nanotubes (SWNT) have excellent potential for use as NO sensors both in vitro and in vivo, but they are not widely used by the research community because they are not readily available in an easy-to-use platform. The Iverson Lab aims to 1) develop new SWNT sensor platforms and modify the current systems to improve sensor specificity and handling, and 2) determine nitric oxide concentration and dynamics with a highly sensitive and accurate sensor. Through the acquisition of a near infrared, hyperspectral confocal microscope, we will be able to more quickly and more accurately accomplish the goals of the R35 parent grant and increase the impact of the funds already supplied by the NIH.