Techniques for efficient entrapment of pharmaceuticals in biodegradable solid micro/nanoparticles.
BACKGROUND
Biodegradable solid particles are potential carriers for both hydrophobic and hydrophilic drugs and have been marketed for prolongation of pharmaceutical activity. In developing such particles, it is important to achieve stable encapsulation of the drugs in the particles and a controlled rate of drug release.


METHODS
In this paper, the principles and techniques for preparing such particles are reviewed.


RESULTS
Overall, it remains difficult to identify a general approach for achieving effective entrapment and controlled release, because these qualities are determined by multiple complex factors. The encapsulation efficiency of drugs in particles can be improved through various techniques, including hydrophobic interaction, covalent bonding, ionic interaction and physical isolation. In addition, the release behaviors of drugs are strongly influenced by environmental conditions as well as the physicochemical properties of the polymers and drugs.


CONCLUSIONS
Solid particles with targeting ability in addition to prolongation of biological activity may have potential for development of a new type of pharmaceutical in the clinical field.
Ishihara
Tsutomu
T
Kumamoto University, Graduate School of Medical and Pharmaceutical Sciences, Oe-honmachi, Kumamoto, Japan. tishihar@kumamoto-u.ac.jp
Mizushima
Tohru
T
D001672:Biocompatible Materials / Q000737:chemistry*; D003692:Delayed-Action Preparations / Q000737:chemistry; D004337:Drug Carriers / Q000737:chemistry*; D006801:Humans; D053758:Nanoparticles / Q000737:chemistry*; D004364:Pharmaceutical Preparations / Q000008:administration & dosage
D001672:Biocompatible Materials; D003692:Delayed-Action Preparations; D004337:Drug Carriers; D004364:Pharmaceutical Preparations