2009). Further, it can incorporate any kind of drugs into nanofibres through
electrospinning technique and is capable to deliver it locally in a faster way. The
biocompatible
and
biodegradable
polymers
like
chitosan,
gelatin,
poly(-
ε-caprolactone), poly(lactic acid), poly(vinyl alcohol) and poly(lactic acid-co-
glycolic acid) are capable to form nanofibre using electrospinning technique.
These nanofibres are capable to appropriate substrate for cell proliferation and
migration which trigger the repairing of the damage tissues and, thereby, encourage
new tissue restoration (Shim et al. 2008; Lee et al. 2009). Polymeric dressing
materials are capable to incorporate and deliver biologically active molecules. But,
the most challenging part in delivering is that any therapeutic agent has to maintain
the therapeutic concentration at the wound site throughout its delivery which
depends on the diffusion mechanism of the drug from the dressing material and its
penetration ability through skin barrier. The controlled release of therapeutic agents
decreases the total amount of released therapeutic agents initially and ultimately
improves its bioavailability for longer period of time which triggers the healing
process of most wounds (Verreck et al. 2003).
30.2
Dressing Materials
For proper healing of wounds, whether it is a minor cut or major incision, it is
necessary to take care of it. Proper dressing of wounds plays an important role in
wound management, and the selection of proper dressing depends on the nature of
wounds. An ideal dressing material should have the following characteristics, viz.
(a) it should maintain proper moist condition surrounding the wound, (b) it should
boost the epidermal migration, (c) it should allow adequate gas exchange between
wound tissue and environment, (d) it should inhibit the bacterial infections, (e) it
should endorse the angiogenesis and connecting tissue generation and (f) it should
be non-adherent to the wound and easy to take out after healing (Dhivya et al. 2015).
From ancient age (2500 BCE), wet to dry dressings have been used to promote
wound debridement, and clay tablets and linen strips soaked in oil or grease covered
with plasters were usually used to heal the wounds. The wounds were cleaned with
milk or water before dressing with honey or resin (Carla Daunton et al. 2012).
Antiseptic dressing was first introduced in the nineteenth century in which antibiotic
drugs were used to prevent the infection and reduce the mortality while in early
twentieth century; the modern dressing material was introduced (Shah 2011).
Generally, traditional dressing includes gauze, lint, plasters, bandages (natural or
synthetic) and dry cotton wool. These traditional dressings are basically used as
primary or secondary dressing for protecting wounds from contamination (Boateng
et al. 2008). But, they need to change frequently to inhibit the softening of the
healthy tissues. Further, these dressings get easily moistened due to excessive wound
drainage which makes them adherent to the wound resulting it painful during
removal. Hence, traditional dressings are better for clean or dry wounds with mild
exudates, or they are useful as secondary dressings. Xeroform™is an example of
non-occlusive dressing (petrolatum gauze with 3% bismuth tribromophenate)
30
Polymeric Vehicles for Controlled Delivery of Ayurvedic Drugs for Wound. . .
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