Abstract:
: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 mum 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 mum 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. (c) 1997 John Wiley & Sons, Inc.
journal_name
Biotechnol Bioengjournal_title
Biotechnology and bioengineeringauthors
Benedetti L,Bertucco A,Pallado Pdoi
10.1002/(SICI)1097-0290(19970120)53:2<232::AID-BITsubject
Has Abstractpub_date
1997-01-20 00:00:00pages
232-7issue
2eissn
0006-3592issn
1097-0290journal_volume
53pub_type
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