[Studies on biodegradable microcapsules of anticancer drugs]

We made biodegradable microcapsules for the controlled release of an anticancer drug. The spherical capsules were designed to be infused repeatedly through an implanted angiographic catheter. The microcapsules were made by the Wurster method, and consisted of a core consisting of lactose and a shell consisting of lecithin, cholesterol, stearic acid, and polyvinylpyrrolidone. The capsules with diameters of 50 to 200 microns could be infused through a catheter. In blood plasma, the capsules absorbed water and disintegrated in 20-30 min. The amount of drug released from the microcapsules in a test of dissolution in a column could be controlled by changes in the thickness of the shell. These capsules will now be tested in rabbits with experimental tumors.