A solvent/non-solvent sintering tech- nique has been devised for joining poly- meric microspheres to make porous matri- ces for use as drug-delivery devices or scaf- folds that could be seeded with cells for growing tissues. Unlike traditional sinter- ing at elevated temperature and pressure, this technique is practiced at room tem- perature and pressure and, therefore, does not cause thermal degradation of any drug, protein, or other biochemical with which the microspheres might be loaded to impart properties desired in a specific application. Also, properties of scaffolds made by this technique are more repro- ducible than are properties of comparable scaffolds made by traditional sintering.

The technique involves the use of two miscible organic liquids: one that is and one that is not a solvent for the affected polymer. The polymeric microspheres are placed in a mold having the size and shape of the desired scaffold, then the solvent/non-solvent mixture is poured into the mold to fill the void volume between the microspheres, then the liq- uid mixture is allowed to evaporate. Some of the properties of the resulting scaffold can be tailored through choice of the proportions of the liquids and the diameter of the microspheres.

This work was done by Cato T. Laurencin, Justin L. Brown, and Lakshmi Nair of the University of Virginia for Johnson Space Center. For further information, contact the Johnson Technology Transfer Office at (281) 483-3809. MSC-24227-1

NASA Tech Briefs Magazine

This article first appeared in the August, 2011 issue of NASA Tech Briefs Magazine.

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