Design and preparation of ethyl cellulose microcapsules of gadopentetate dimeglumine for neutron-capture therapy using the Wurster process.
Microcapsules of hygroscopic, highly water-soluble gadopentetate dimeglumine (Gd-DTPA-DM) for use in preliminary in vivo experiments for neutron-capture therapy were designed. They were prepared with such properties as a particle size small enough to be suspended and injected through a syringe, a negligible release of Gd-DTPA-DM, and a high drug content by means of the Wurster process, a spray coating method using a spouted bed with a draft tube. They were composed of lactose cores of 53-63 microm, an undercoat of ethyl cellulose (EC) and polyvinylpyrrolidone (PVP), a drug-layer of Gd-DTPA-DM, EC and PVP, a waterproof coat and a release-sustaining overcoat of EC and cholesterol (1:1), and a surface treated with hydrogenated egg lecithin. By curing at 110 degrees C for 30 min after mixing with 20% pulverized mannitol powder, the 20% overcoating suppressed the release of Gd-DTPA-DM from 75-106 microm microcapsules to less than 10% for the first 20 min, which was the period required to prepare a suspension, inject it and irradiate the neutron. The microcapsules could be used to confirm that the intracellular presence of Gd is not critical in gadolinium neutron-capture therapy.
Fukumori
Y
Y
Faculty of Pharmaceutical Sciences, Kobe-Gakuin University, Japan.
Ichikawa
H
H
Tokumitsu
H
H
Miyamoto
M
M
Jono
K
K
Kanamori
R
R
Akine
Y
Y
Tokita
N
N
D002482:Cellulose / Q000031:analogs & derivatives*; D004338:Drug Combinations; D004339:Drug Compounding; D005682:Gadolinium; D019786:Gadolinium DTPA; D008536:Meglumine; D017247:Neutron Capture Therapy; D009942:Organometallic Compounds; D010316:Particle Size; D004369:Pentetic Acid
D004338:Drug Combinations; D009942:Organometallic Compounds; D008536:Meglumine; D004369:Pentetic Acid; C013517:ethyl cellulose; D002482:Cellulose; D005682:Gadolinium; D019786:Gadolinium DTPA