title: In situ double-beam NADH laser fluorimetry: choice of a reference wavelength.
abstract: A double-beam laser fluorimeter, using a single optical fiber to guide the lights, was constructed for in situ and on-line monitoring of NADH concentration [( NADH]) from normally blood-perfused living tissues. The device was tested on an isolated blood-perfused rat heart system to determine the most efficient reference wavelength for the compensation of the hemodynamic artifact induced by blood circulation in the tissues on the fluorescence measure; 586 nm was found to be an accurate reference wavelength, and a mathematical relationship was established that allowed the digital treatment of the measured fluorescence to give a signal (compensated fluorescence) that varied only with [NADH] in the volume of tissue investigated.
mesh_terms: D000818:Animals; D001769:Blood; D005336:Fiber Optic Technology; D005470:Fluorometry / Q000379:methods; D006400:Hematocrit; D000860:Hypoxia / Q000378:metabolism; D007834:Lasers; D008433:Mathematics; D008955:Models, Cardiovascular; D009206:Myocardium / Q000032:analysis; D009243:NAD / Q000032:analysis*; D055100:Optical Fibers; D010477:Perfusion; D051381:Rats
chemical_list: D009243:NAD