This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Fluorescence imaging of cells and tissue can be used to evaluate beta-NADH redox and location. At low temperature beta-NADH fluorescence intensity is known to increase and therefore sensitivity of imaging increases. We have evaluated the temperature dependence of steady-state fluorescence for beta-NADH in glycerol/water solution and in trehalose/sucrose glass. The temperature range studied was 290 K to 12 K. The steady-state fluorescence of beta-NADH in glycerol/water was found to increase ~16 fold and the emission to shift by about 35 nm to the blue as temperature decreased. Much smaller changes were seen for fluorescence of beta-NADH in sugar glass. It is suggested that the sensitivity of beta-NADH fluorescence is related to water relaxation around the excited state molecule. We would like to probe further if the fluorescence lifetime of beta-NADH is dependent upon water concentration in glycerol/water mixtures.