文摘
Luminescence-based imaging-fiber oxygen sensors(IFOSs) were utilized for the in situ measurement ofoxygen consumption from intact perfused mouse hearts.IFOSs were fabricated using a technically expedient,photoinitiated polymerization reaction whereby an oxygen-sensitive polymer matrix was immobilized in a preciselocation on an imaging fiber's distal face. The oxygen-sensing layer used in this work comprised a transitionmetal complex, Ru(Ph2phen)32+, entrapped in a gas-permeable photopolymerizable siloxane membrane (PS802).The transduction mechanism was based upon the oxygencollisional quenching of the ruthenium complex luminescence; detection was performed utilizing an epi-fluorescence microscope/charge coupled device imaging system.IFOS measurements from working mouse hearts werevalidated through concurrent, blind, ex situ blood gasanalyzer (BGA) measurements. The BGA and IFOS methodologies were utilized successfully to measure oxygenconcentrations in aortic and pulmonary artery perfusatesfrom the working mouse heart before and after isoproterenol administration. Coupled with coronary-flow measurements, these data were used to calculate myocardialoxygen consumption. Regression analysis of measurements of myocardial oxygen consumption showed thatthere was a strong correlation between the values generated by the BGA sampling and those obtained via in situIFOS methods. To our knowledge, this research represents the first report of in situ fiber-optic sensor monitoring of oxygen content from the intact, beating mouse heart.