Measurement of pO 2 by luminescence lifetime spectroscopy: A comparative study of the phototoxicity and sensitivity of [Ru(Phen) 3 ] 2+ and PdTCPP in vivo

• Published in: Journal of biophotonics Vol. 10; no. 5; pp. 708 - 717
• Main Authors: Huntosova, Veronika, Gerelli, Emmanuel, Horvath, Denis, Wagnieres, Georges
• Format: Journal Article
• Language: English
• Published: Germany 01.05.2017
• Subjects: Animals; Chick Embryo; Chorioallantoic Membrane - chemistry; Luminescence; Mesoporphyrins - chemistry; Metalloporphyrins - chemistry; Organometallic Compounds - chemistry; Oxygen - analysis; Partial Pressure; Phenanthrolines - chemistry; Spectrum Analysis; oxygen probe; in vivo; vascular photodamage; statistical data analysis; time-resolved; bootstrapping method
• ISSN: 1864-063X; 1864-0648
• DOI: 10.1002/jbio.201600127

Dysfunctions in tissue metabolism can be detected at early stages by oxygen partial pressure (pO ) measurement. The measurement of emission lifetimes offers very promising and non-invasive approach to estimate pO in vivo. This study compares two extensively used oxygen sensors and assesses their in vivo oxygen sensitivity and phototoxic effect. Luminescence lifetime of Ru-polypyridyl complex and of Pd-porphyrin is measured in the Chick's Chorioallantoic Membrane (CAM) model with a dedicated optical fiber-based, time-resolved spectrometer. The Pd-porphyrin luminescence lifetimes measured in the CAM model exposed to different pO levels are longer and have a broader dynamic range (10-100 μs) than those of Ru-polypyridyl complex (0.6-1 μs). The combined statistical analysis based on an estimate of the kurtosis and skewness, bootstrapping method and routine normality tests is performed. The indicators of the averages and signal to noise ratio stability are also calculated. The combination of several data processing allows selection of the better sensor for a given application. In particular, it is found that the advantage of Ru-polypyridyl complex over Pd-porphyrin is two-fold: i) Ru-polypyridyl complex datasets have consistently better statistical characteristics, ii) Ru-polypyridyl exhibits lower cytotoxicity.