Halloysite Nanotube/PLGA Composite Materials for Controlled Antibiotic Release

Effective wound treatment is an issue of prime concern in medicine. Halloysite, an aluminosilicate clay, is a promising alternative for drug delivery as it is cheap, abundant and nontoxic. Pure halloysite can be loaded with up to 30 wt% chemical agent while encapsulation extends release from minutes to several hours or days. Although PVOH and PMMA/halloysite composites are common, experiments with other biologically relevant polymers such as PLGA are limited in literature. Additionally, most halloysite studies use tetracycline HCl, a small, water soluble antibiotic. Other antibiotics are larger and more potent, imposing release limitations. This project aims to advance further understanding of controlled release from halloysite/polymer systems by experimentally investigating these areas. Controlled release of the antibiotics gentamicin sulfate and ofloxacin will be studied and compared to tetracycline, and release rates will be quantified by periodic determination of the antibiotic concentration in the sample; concentration can be directly calculated from UV absorbance of the supernatant. Compared to pure PLGA, it is expected that antibiotic release from PLGA/halloysite composites is retarded. Additionally, the effects of the LA:GL ratio on degradation and release will be studied. It is also expected that the use of drug-loaded halloysite-containing polymeric films is a promising technique for the long term controlled release of antibiotic agents.  These composite materials are promising for the treatment of infected wounds, prophylactic treatment of battle field injuries and the development of antimicrobial surfaces.