Preparation of gelatin nanocapsules and their pharmaceutical characterization

A production process is described that yields nanocapsules instead of nanoparticles. The process allows the encapsulation of lipophilic drugs such as triamcinolone acetonide with an O/W emulsion system. The capsular structure of the products was confirmed by transmission and scanning electron microscopy. The nanocapsules displayed a mean size of 141 ± 47 nm to 523 ± 340 nm (mean ± S.D.) and a drug content of 7 % to 15.4 % w/w. Drug release experiments showed that the encapsulated triamcinolone acetonide was released more slowly than micronized drug crystals. A more pronounced retarded release could be achieved by raising the pH during the hardening reaction or by encapsulating cholesterol into the nanocapsules.