Production of micronic particles of biocompatible polymer using supercritical carbon dioxide

• Published in: Biotechnology and bioengineering 1997-01, Vol.53 (2), p.232-237
• Main Authors: Benedetti, Luca, Bertucco, Alberto, Pallado, Paolo
• Format: Article
• Language: English
• Subjects: antisolvent; biocompatible polymer; Biological and medical sciences; Biotechnology; drug delivery system; Fundamental and applied biological sciences. Psychology; Health. Pharmaceutical industry; Industrial applications and implications. Economical aspects; Miscellaneous; rapid expansion; supercritical fluid
• ISSN: 0006-3592; 1097-0290
• DOI: 10.1002/(SICI)1097-0290(19970120)53:2<232::AID-BIT15>3.0.CO;2-M

Three micronization techniques, based on the use of supercritical carbon dioxide, were investigated to produce microspheres of a natural biocompatible polysaccharide. Particles smaller than 20 μm were obtained by means of the rapid expansion of a supercritical solution method (RESS), both with and without cosolvents. The mean diameter of the particles was reduced to about 0.5 μm when a solution of the polymer in an organic solvent was expanded by using carbon dioxide as a supercritical antisolvent (SAS). The SAS process was operated both in a continuous and in a batch mode. The former leads to aggregated structures and fibers, and the latter to the formation of micronic spherical particles. It was found that the experimental temperature did not substantially affect the shape and dimension of the particles. A stronger dependence is shown with respect to the solute concentration in the starting solution. The proposed method is attractive as the basis of a new process for the preparation of drug delivery systems. © 1997 John Wiley & Sons, Inc.