Preparation and evaluation of lyophilized iopromide-carrying liposomes for liver tumor detection.
OBJECTIVE
The objective of the present investigation was to demonstrate a new method for the production of iopromide-carrying liposomes. We studied biodistribution and elimination behavior, as well as the computed tomography (CT) liver imaging properties.


METHODS
Iopromide-containing liposomes were prepared by the ethanol evaporation method and subsequently lyophilized. The resuspended liposomes were tested in rats and rabbits.


RESULTS
After resuspension, liposomes with a mean diameter of 467 +/- 66 nm and an encapsulation rate of 41.5 +/- 5.5% were obtained. In rats, a marked accumulation of liposomal iopromide was found in the liver and spleen. In rabbits, complete renal elimination of iopromide within 7 days was demonstrated. At a dose of 150 mg total iodine/kg, a small tumor (< 0.5 cm) could be detected in a VX-2-bearing rabbit.


CONCLUSIONS
The ethanol evaporation method proved to be suitable for the reproducible large-scale manufacture of iopromide liposomes with high encapsulation. The resuspended liposomes displayed favorable biodistribution, elimination and imaging characteristics.
Sachse
A
A
Schering AG, PHZE Parenterale AF, Germany.
Leike
J U
JU
Rössling
G L
GL
Wagner
S E
SE
Krause
W
W
D000818:Animals; D003287:Contrast Media; D004337:Drug Carriers; D005260:Female; D005612:Freeze Drying; D007472:Iohexol / Q000031:analogs & derivatives* / Q000493:pharmacokinetics; D008081:Liposomes; D008114:Liver Neoplasms, Experimental / Q000000981:diagnostic imaging*; D008297:Male; D011817:Rabbits; D051381:Rats; D017208:Rats, Wistar; D014018:Tissue Distribution; D014057:Tomography, X-Ray Computed
D003287:Contrast Media; D004337:Drug Carriers; D008081:Liposomes; D007472:Iohexol; C038192:iopromide