I am sure this sort of thing is well-known, but it hit me between the eyes this morning:
"New polymer-halloysite hybrid materials--potential controlled drug release system.
Ghebaur A, Garea SA, Iovu H.
Advanced Polymer Materials Group, University Politehnica of Bucharest,
149 Calea Victoriei, 010072 Bucharest, Romania.
Abstract
New hybrid materials based on a natural host (halloysite), biodegradable polymer (poly(vinyl alcohol)) and diphenhydramine hydrochloride as drug were synthesized and tested as a potential controlled drug delivery system. The formation of these hybrid materials was proved using different characterization methods like Spectroscopic techniques (FTIR, XPS and UV-vis), thermogravimetrical analysis and scanning electron microscopy (SEM). The hybrid materials exhibit different features regarding the drug release. In vitro drug release tests showed that there are several factors which exhibit a strong influence on the drug release rate. Thus the initial drug concentration used at the hybrid materials synthesis, the presence of a polymer in the hybrid composition and the pH value of the release medium are the most important factors.
Copyright © 2012. Published by Elsevier B.V. PMID: 22820481"