2005 Ohio Student Research Forum

Abstract

Controlled Drug Release from Polymer-Clay Nanocomposite Adhesives for Transdermal Drug Delivery
Anil Birdi
Case Western Reserve University, Department of Biomedical Engineering
Mentor: Dr. Syed Qutubuddin

Polymer-clay nanocomposites are a new class of materials with nanometer sized clay particles dispersed within a polymer matrix. This hybrid material enhances several properties that are not shared by conventional clays or polymers. Nanocomposites offer higher strength and stiffness, enhanced barrier properties including reduced permeability to liquids and gases, higher temperature durability, and reduced flammability. Many of these enhanced properties are due to the extremely small dimensions of the clay particles and the large interfacial area per unit volume of the dispersed phase. The increased interfacial interactions in polymer-clay nanocomposites and improved barrier properties is predicted to allow for a slower, more controlled release of drugs from polymer matrices. One controlled delivery system in which nanocomposites may help in slowing down the release of drugs is in transdermal drug delivery systems which use pressure sensitive adhesives in medical patches to release drugs through the skin.

Exfoliation, or complete dispersion of clay particles in the polymer matrix, is desired for improving properties of the polymer. This was achieved in polydimehtyl siloxane (PDMS) adhesives and confirmed by an increase in the d-spacing between clay layers as shown in X-ray diffraction spectra, Release profiles of solvent blue 35, a dye which can be used to act as a drug, from PDMS nanocomposite adhesives with different amounts of clay were obtained to determine whether clay loading has an effect on the release of drugs. The release profiles showed that PDMS adhesives with a higher clay loading had a slower release of the drug. The amount of clay loading in nanocomposite polymers can therefore be used an effective method for controlling the amount of drug released from polymer adhesive matrices in transdermal drug delivery to maintain optimal blood level concentration of a drug.