STUDY OF SOME POLYMERIC SYSTEMS FOR TOPICAL BIOMEDICAL APPLICATIONS

Abstract

Polymer-based delivery systems provide a considerable platform for drug delivery technology primarily because of their ease of processing and the ability of researchers to readily control their chemical and physical properties via molecular synthesis. Moreover, polymeric drug delivery systems were shown effective in enhancing drug targeting over other delivery systems, lowering systemic drug toxicity, improving treatment absorption rates, and providing protection for pharmaceuticals against biochemical degradation. Numerous polymeric-carriers have been developed for the controlled delivery of biologically active molecules such as polymer-drug conjugates, micelles, particulate systems (capsules and spheres), sponges, films, and fibers. Among polymeric drug delivery systems, researchers are now turning to advances in the worlds of micro- and nanotechnology.0 l

Polymer-based drug delivery systems pave the way to the most promising applications especially in the fields of biomedicine and biotechnology. Among those applications, topical biomedical polymeric systems open up a number of opportunities with regard to controlled local drug delivery in many skin diseases, postoperative local chemotherapy, the management of wound-related conditions, prevention of post-surgical adhesions, tissue support and guided regeneration in tissue engineering.(2-4)

Non-healing or slow healing wounds represent a major health burden and drain on resources, contributing to substantial disability, morbidity, and costs. This shifted the researches in the field of wound management towards emerging technologies, such as the use of biocompatible p.olymeric wound dressings for achieving improved wound healing (Sl_ Such dressings should provide two main prerequisites: (1) it should physically resemble the r..anofibrous features of extracellular matrix (ECM) with suitable mechanical properties. It should also be able to promote cell adhesion, spreading and proliferation. (2) It could deliver suitable bioactive agents, (including wound healing-drugs, growth factors, and antimicrobial agents), in a controlled manner during healing. The fabrication of such multifunctional polymeric scaffolds for biomedical applications often requires an interdisciplinary approach combining pharmaceutical technology , materials science, physics, chemistry, biology and engineering.(6

In the past several years the usage of electrospun fibrous scaffolds for biomedical applications has attracted a great deal of attention. It is believed that its favorable properties have provided potential applications as wound dressings (?-Ill. The use of ultrafine fibers as a carrier system for drug delivery and the variables implicated therein are still in the early stage exploration. The work in this thesis will be focused on the development of multifunctional electrospun polymeric ultrafine fibers for simultaneous drug delivery and wound healing.