Abstract

Provided is a method for preparing a true, homogeneous solution of a pharmaceutical substance dissolved in an organic solvent in which the pharmaceutical substance is not normally soluble. Solubilization is obtained by forming a hydrophobic ion pair complex involving the pharmaceutical substance and an amphiphilic material. The resulting organic solution may be further processed to prepare pharmaceutical powders. A biodegradable polymer may be co-dissolved with the pharmaceutical substance and the amphiphilic material and may be incorporated into a pharmaceutical powder. A preferred method for preparing pharmaceutical powders is to subject the organic solution to gas antisolvent precipitation using a supercritical gas antisolvent such as carbon dioxide. Also provided is a method for making hollow particles having a fiber-like shape which would provide enhanced retention time in the stomach if ingested by a human or animal host.

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