title: Oxygenation measurement by multi-wavelength oxygen-dependent phosphorescence and delayed fluorescence: catchment depth and application in intact heart.
abstract: Oxygen delivery and metabolism represent key factors for organ function in health and disease. We describe the optical key characteristics of a technique to comprehensively measure oxygen tension (PO(2)) in myocardium, using oxygen-dependent quenching of phosphorescence and delayed fluorescence of porphyrins, by means of Monte Carlo simulations and ex vivo experiments. Oxyphor G2 (microvascular PO(2)) was excited at 442 nm and 632 nm and protoporphyrin IX (mitochondrial PO(2)) at 510 nm. This resulted in catchment depths of 161 (86) µm, 350 (307) µm and 262 (255) µm respectively, as estimated by Monte Carlo simulations and ex vivo experiments (brackets). The feasibility to detect changes in oxygenation within separate anatomical compartments is demonstrated in rat heart in vivo. Schematic of ex vivo measurements.
authors.affiliation: Department of Anesthesiology, Laboratory of Experimental Anesthesiology, Erasmus MC - University Medical Center Rotterdam, Rotterdam, The Netherlands.|Department of Medical Intensive Care, University Hospital Basel, Switzerland.|Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Gianmarco M
authors.initials: GM
authors.lastname: Balestra
authors.affiliation: Department of Biomedical Engineering and Physics, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Maurice C G
authors.initials: MC
authors.lastname: Aalders
authors.affiliation: Department of Anesthesiology, Laboratory of Experimental Anesthesiology, Erasmus MC - University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: Patricia A C
authors.initials: PA
authors.lastname: Specht
authors.affiliation: Department of Translational Physiology, Academic Medical Center, Amsterdam, The Netherlands.
authors.forename: Can
authors.initials: C
authors.lastname: Ince
authors.affiliation: Department of Anesthesiology, Laboratory of Experimental Anesthesiology, Erasmus MC - University Medical Center Rotterdam, Rotterdam, The Netherlands.
authors.forename: Egbert G
authors.initials: EG
authors.lastname: Mik
mesh_terms: D000818:Animals; D005240:Feasibility Studies; D008297:Male; D008665:Metalloporphyrins / Q000737:chemistry; D009010:Monte Carlo Method; D009206:Myocardium / Q000378:metabolism*; D010100:Oxygen / Q000378:metabolism*; D011524:Protoporphyrins / Q000737:chemistry; D051381:Rats; D017208:Rats, Wistar; D013050:Spectrometry, Fluorescence / Q000379:methods*
chemical_list: D008665:Metalloporphyrins; D011524:Protoporphyrins; C474536:oxyphor G2; C028025:protoporphyrin IX; D010100:Oxygen
keywords: Monte Carlo simulation; Oxyphor G2; catchment depth; delayed fluorescence; myocardial; oxygen measurement; oxygen‐dependent quenching; phosphorescence; protoporphyrin IX