Calibration of pd-porphyrin phosphorescence for oxygen
concentration measurements in vivo.
Sinaasappel, M., and C. Ince.
Department of Anesthesiology, Academic Medical Centre, University
of Amsterdam, Meibergdreef 9,1105 AZ Amsterdam, The Netherlands,
Phone 31-20-5662533, Fax 31-20-6979441
APStracts 3:0320A, 1996.
Quantitative measurement of oxygen concentrations in the
microvasculature is of prime importance to issues related to oxygen
transport to tissue. The introduction of the quenching of the Pd
-porphyrin phosphorescence as oxygen sensor in vivo by Wilson et al.
(J. Appl. Physiol. 74: 580-589, 1993) has provided in this context a
major advance in this area of research. For in vivo application, the
dye is coupled to albumin to restrict the dye to the circulation and
to measure oxygen in the physiological range. In this study a
phosphorimeter with a gated photomultiplier is presented and
validated. Furthermore, a non-linear fit method using the Marquardt
-Levenberg algorithm is used to calculate the decay time. With this
new phosphorimeter calibration measurements were performed to
investigate the effects of pH, temperature and diffusivity. The
results present a preparation method for albumin coupling of the dye
which eliminates the pH dependency of the quenching kinetics.
Furthermore the decreased oxygen diffusivity of serum was compared to
water showing that calibration constants measured in water can be
extrapolated to serum.
Received 12 July 1995; accepted in final form 18 June 1996.
APS Manuscript Number A756-5.
Article publication pending Journal of Applied Physiology.
ISSN 1080-4757 Copyright 1996 The American Physiological Society.
Published in APStracts on 4 July 96