Controlled release of dexamethasone acetate from biodegradable and biocompatible polyurethane and polyurethane nanocomposite

Abstract

Polyurethanes and polyurethane nanocomposites can be applied to control the release of drugs previously incorporated into these materials. In this study, dexamethasone acetate (ACT) was incorporated into biodegradable and biocompatible polyurethane and polyurethane containing montmorillonite nanoparticles. Fourier transform infrared spectroscopic technique showed no strong interactions between drug and polymers. Data obtained from X-ray diffraction and small angle X-ray scattering indicated that the incorporation of ACT did not disturb the polymer morphology, but montmorillonite led to a less defined phase separation between hard and soft segments of polyurethane. The in vitro release studies demonstrated that nanoparticles increased the rate of ACT release possibly because these particles have a hydrophilic surface that increases the absorption of water and accelerates the hydrolysis of the polymer. The in vivo short-term biocompatibility studies demonstrated adequate interfacial interaction between polyurethane and subcutaneous tissue and a discreet inflammatory response which was completely resolved in 14 days.

Keywords::

• Polyurethane
• nanocomposite
• dexamethasone acetate
• in vitro controlled release
• in vivo biocompatibility

Acknowledgments

The author would like to acknowledge the financial support from the following institutions: National Council for Scientific and Technological Development (CNPq), a foundation linked to the Ministry of Science and Technology (MCT) of the Brazilian Government; the State of Minas Gerais Research Foundation (FAPEMIG); and the National Synchrotron Light Laboratory (Brazil) for the use of the SAXS beamline facilities.

Declaration of interest: The authors report no conflicts of interest.