T. Yamaguchi et al., IN-VIVO ESR STUDIES ON PHARMACOKINETICS AND METABOLISM OF PARENTERAL LIPID EMULSION IN LIVING MICE, Pharmaceutical research, 13(5), 1996, pp. 729-733
Purpose. We applied non-invasive and real-time method with in vivo ESR
spectroscopy to determining pharmacokinetics and metabolism of lipid
emulsion as a drug carrier in living mice. Methods. A spin-labeled tri
glyceride (SL-TG) was newly synthesized and lipid emulsion containing
SL-TG was prepared. In vivo ESR spectra in mice were observed after in
travenous administration of the lipid emulsion. Results. In vivo ESR s
pectra consisted of three components, coinciding with the in vitro spe
ctra of SL-TG particles, free and immobilized fatty acids. The amount
of the components depended on both the observing domain and the period
after administration. In the chest, all three components were observe
d, while SL-TG particle was lacking in the abdomen. The half-life of t
he lipid particles in the chest was 2 hr. Conclusions. Non-invasive an
d real-time analysis of drug carriers in living animal is successfully
accomplished using an in vivo ESR method.