Wound healing is a highly complex physiological
process involving interplay of various cellular and biochemical factors. A few
critical stages include inflammation, cell migration, angiogenesis, matrix
synthesis, collagen deposition and re-epithelization. Various wound dressings have
emerged over the years to assist the process of wound healing that also ensure
avoidance of infection. An ideal wound dressing material must keep the wound
moist, allow gaseous exchange, inhibit bacterial growth and absorb wound
exudates. Also the disappearance of the scaffolds on the wound must mirror the
reappearance of healed tissue. Many scaffolds initially fill up the space
otherwise occupied by normal tissue and then provide a framework for its regeneration.
We have earlier fabricated scaffolds and films of
chitosan-zinc complex. Chitosan apart from being anti-bacterial is
biocompatible, biodegradable, hydrating (providing a moist environment to the
healing wound). Zinc on the other hand offers protection from microbes and also
positively affects the process of wound healing. The in vitro and in vivo
studies conducted with these scaffolds have suggested a significant enhancement in
healing compared to control. Taking this work forward, we have replaced chitosan with
N,O-carboxymethylchitosan (N,O-CMCh), a water soluble derivative of chitosan
with better properties (particularly antibacterial) and have successfully reported the antibacterial
superiority of N,O-CMCh-Zn complex over Ch-Zn.
We are currently exploring hydrogels as a scaffold
system for wound healing. They are appealing mainly because of their closeness to
the extracellular matrix of tissues. We have fabricated a composite scaffold
with a novel polysaccharide base comprising a drug (antibacterial and wound
healer) and keratin. These upon placement on the wound would convert to a
hydrogel offering exudates absorption and moist environment.
Microneedles
Microneedles have been reported to
be painless and can deliver the therapeutic moieties in a controlled manner with
the convenience
of self-administration. Our research in this
area is focused on fabrication of microneedles for efficient delivery of
protein, vaccine and potent therapeutic moieties for systemic and local drug
delivery. Exploiting
microneedle-based transdermal devices and formulations will have a great impact
in future medicine. Our lab is investigating the feasibility of microneedle
fabrication, insertion capabilities and mechanical properties of the
microneedles.
Coronary Stents
Biodegradable coronary stents as drug
delivery systems are reported to be safer and promising device compared to bare
metal stents and drugs eluting stents. In our lab, biodegradable stents are
being investigated for percutaneous coronary intervention to support mechanical
need of healing artery. We are evaluating drug loaded nanoparticles as a promising
technology for improved and sustained drug delivery to the diseased vessel walls.
Our studies are focused on fabricating biodegradable coronary drug eluting
stents combining the benefits of nanotechnology.