|
The in vivo performance of a Fluorescence Molecular Tomography system as a function of pathophysiological
parameters that determine the penetration of nonbinding fluorescent nanoparticle was examined through imaging of
a series of three tumor models. The pathophysiological parameters examined were, vessel density, interstitial fluid
pressure (IFP), and collagen content. Drug delivery and IFP were measured in vivo via fluorescence spectroscopy
and a fiber-optic coupled pressure probe. Vessel density and collagen content were determined ex vivo through
histochemical analysis. The kinetics of the 40 nm,10000 KDa, fluorescent particles, which were injected into the tail
vein of the mice, was monitored by sequential excitation of the tissue on and off the tumor site through employment
of sixteen source detector pairs interspersed linearly in reflectance geometry. Each optical fluorescence data set was
collected at discrete time intervals in order to monitor drug uptake for a period of 45 minutes. The kinetics of the
drug delivery and the average nanoparticle uptake were correlated with the vessel density, interstitial pressure and
collagen content. The results of the correlations were verified to be consistent with the published relationship
between the three pathophysiological parameters and nanoparticle drug delivery.
|
