|
Developing novel technologies to deliver safe
levels of therapeutic agents is important to
decrease the side effects caused by overdose or
inneffectiveness due to underdose. In this
project we focus on developing strategies to
deliver drugs by different approaches. Couple of
these projects are described below. |
|
|
Transdermal drug delivery-Development
of transdermal drugs requires the identification
of suitable delivery mechanisms. Much effort has
been directed towards the search for specific
chemical or chemical combinations that could
enhance drug penetration. However, effective
chemical penetration enhancers (CPE) themselves
permeate skin thereby eliciting some undesired
reactions. Reliable and quantitative models for
predicting precutaneous penetration and
irritation as a function of chemical structure
are required. The development of these models
enables us to virtually screen for viable
penetration enhancers thereby reducing the need
for expensive experiments. The major goal of
this project is to integrate non-linear,
theory-based
quantitative-structure-property-relationship (QSPR)
modeling and robust genetic algorithms (GAs) to
facilitate the design of improved CPEs. This is
a collaborative project with Dr. Khaled Gasem
and Dr. Robert L Robinson in Chemical
Engineering at Oklahoma State University. |
|
|
Oral delivery.
In this
cutting edge technology, pH-sensitive hydrogels
are loaded with insulin and can be administered
through the oral cavity. Unique feature of these
hydrogels are that they form interpolymer
complexes in an acidic environment and protect
the insulin from the harsh stomach environment,
a challenge to overcome for oral drug delivery.
Insulin is safely released in the intestine due
to the swelling of the carrier matrix at high pH
and the delivery rate is influenced by particle
size. Oral administration of insulin showed
responses similar to subcutaneous delivery,
suggesting the successful delivery of insulin
orally. |
|
|
Nanoparticle delivery.
Many
therapeutic molecules have short half lives and
one way to extend their life span is
encapsulation. Nanoparticles are employed in
various therapeutic approaches for innovative
drug delivery strategies. We believe that
encapsulating regulatory factors and delivering
them at a controlled rate would provide
opportunity: i) to create heterogeneous
microenvironments within the porous matrix,
unlike exogenous supplementation which creates a
homogeneous microenvironment, ii) to
continuously deliver regulatory factor,
minimizing the time dependent variation in
concentration, attributed to the frequency of
the media change and half life of different
growth factors; iii) to address the concerns
related to incomplete secretion of growth
factors into the cell culture medium in addition
to the efficacy of genetically modified cellular
components. pH-sensitive chitosan nanoparticles
prepared by ionic gelation of chitosan with
tripolyphosphate (TPP) anions is the most
popular because of its non-toxic property and
quick gelling ability. The chitosan–TPP
nanoparticles system exhibits attractive
features including formation under mild
conditions; homogeneous and adjustable size and
a positive surface charge that can be easily
modulated and a great capacity for the
association of proteins, oligonucleotides, and
plasmids. Similar technology also exists to form
gelatin nanoparticles. Optimization of growth
factor delivery and evaluation of cellular
interactions in the matrices will help their
usage in tissue healing. |
|
