Dense gas processing of micron-sized drug formulations incorporating hydroxypropylated and methylated beta-cyclodextrin.

Purpose: Because of their importance in pharmaceutical applications, hydroxypropyl-beta-cyclodextrin and methyl-beta-cyclodextrin have been selected to study the formation of micronized complexes incorporating active pharmaceutical ingredients (APIs) and cyclodextrins (CDs) by dense gas (DG) processing.

Methods: A single-step DG technique was used as an alternative to conventional methods for the manufacturing of API/CD complexes. The DG technology is highly attractive in the pharmaceutical industry because of its potential to generate micronized particles with controlled particle size distributions at moderate operating conditions. The effect of the aerosol solvent extraction system (ASES) processing on the dissolution performance of naproxen (NPX) was examined.

Results: The CDs were produced as microspheres smaller than 3 microm. The coprecipitation of each CD with NPX resulted in the production of microparticles with enhanced dissolution rates.

Conclusions: The ASES was operated under mild conditions and generated micron-sized spherical particles that could be of particular interest in formulations for pulmonary delivery. Particular advantages of the technique are that (1) nontoxic solvents are used, and (2) it is suitable for the processing of thermally labile compounds. The proposed process can create opportunities to improve current administration routes and exploit novel delivery systems for drug formulations incorporating CDs.