Bi-Layer Composite Dressing of Gelatin Nanofibrous Mat and Poly Vinyl Alcohol Hydrogel for Drug Delivery and Wound Healing Application:<I>In-Vitro</I> and <I>In-Vivo</I> Studies

Abstract

Present investigation involves the development of a bi-layer dressing of gelatin nanofibrous mat loaded with epigallocatechin gallate (EGCG)/poly vinyl alcohol (PVA) hydrogel and its in-vivo evaluation on full-thickness excision wounds in experimental Wistar rats. Nanomorphological observation, porosity, effect of crosslinking on tensile strength, physical stability and drug release profile in phosphate buffer and biocompatibility aspects of electrospun nanomat were investigated by various physico-chemical tools. EGCGa release profile was found to increase from 2-4 days with decreasing crosslinking time from 15 to 5 min. PVA hydrogels were prepared by freeze-thaw method and has been utilized as a protective and hydrating outer layer of the bi-layer dressing. Topical application of bi-layer composite dressing loaded with EGCG improve the healing rate in experimental rats as acute wounds model which was evidenced by significant increase in DNA (approximately 42%), total protein (approximately 32%), hydroxyproline (approximately 26%) and hexosamine approximately 24%) contents. A faster wound contraction was observed in wounds treated with composite dressing from approximately 14% to 47%. Histopathological examination revealed significant improvement in angiogenesis, re-epithelialization and less inflammatory response in comparison to control. Van-Gieson's collagen stains revealed matured, compact and parallel deposition of collagen fibrils on day 12. These results were supported by up-regulated expressions of matrix metalloproteinase (MMPs-2 and 9) by gelatin zymography. Control release of EGCG, 3D porous architecture of nanofibrous scaffolds as well as moist microenvironment provides ideal conditions for uninterrupted wound healing.

Electrospun polyurethane-dextran nanofiber mats loaded with Estradiol for post-menopausal wound dressing

“…Electrospun nanofibers were found to be very effective to be used as the wound dressing material mainly due to its architectural superiority. The electrospun nanofiber can mimic the extra cellular matrix (ECM) environment which will help the host cells to grow and create a new natural cellular matrix [21,22]. Most importantly the preferred therapeutic materials can be introduced to the nanofiber matrix using the electrospinning process [17,23,24], that can seriously affect the wound healing.…”

Regenerative nanomedicine: current perspectives and future directions

“…An interesting study by Jaiswal et al has shown that poly(vinyl alcohol) hydrogel impregnated with epigallocatechin gallate is very effective in healing wounds by improving angiogenesis, restoring epithelialization, and decreasing the inflammatory response. 52 …”

Development of a nanofibrous wound dressing with an antifibrogenic properties in vitro and in vivo model

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