|
Background
Michael marks grew up in Roxboro, North Carolina.
He graduated with a B.S. in Chemical Engineering
from North Carolina State University in 2005. As an
undergraduate he researched self assembled
monolayers (SAM’s) on gold substrates for Dr. Peter
Kilpatrick at NCSU. He also worked three semesters
at Eastman Chemical Company and one at Talecris
Biotherapeutics in various research fields. He has
since enrolled in the graduate program in Chemical
Engineering at the University of Texas at Austin and
is seeking a Ph.D. under Dr. Peppas.
Research Summary
Considering the acidic conditions and the
proteolytic enzymes present in the stomach, the
effective oral delivery of therapeutic proteins and
peptides to the small intestine is a formidable
task. It is further complicated by difficulties in
getting relatively large therapeutic protein
molecules to be absorbed by the selectively
permeable epithelium of the small intestine.
A unique, controlled-release system for oral
delivery of proteins has been invented by a unique
molecular design of its carrier components. The
system consists of a gel-like material that exhibits
“complexation by hydrogen bonding” and has
pH-dependent swelling properties. This means that it
exhibits properties of fast expansion and
contraction. It is stable in the acidic conditions
of the stomach before swelling rapidly and releasing
the therapeutic proteins upon transition to the
basic conditions of the small intestine. The unique
components of the system provide total protection of
the therapeutic protein until it is released in the
small intestine.
In addition, the new protein release system
exhibits properties of mucoadhesion to the mucosa of
the upper small intestine by “intelligent tethers”
that protrude from the carrier. The system can bind
calcium locally, thus leading to opening of the
tight junctions between the epithelial cells of the
upper small intestine. Some inhibition of the
proteolytic activity of the enzymes in the upper
small intestine has been shown.
Therefore, the goal of my PhD Thesis will be to
prepare and characterize novel micro- and
nanoparticles of mucoadhesive hydrogels as well as
to perform fundamental studies by understanding
(from a physicochemical point of view) how tethered
chains of biocompatible polymers such as
poly(ethylene glycol) (PEG) would affect the
adhesion of synthetic gels on mucosal surfaces and
the cell toxicity in contact with cell lines such as
CaCo-2 cells. The results from this study are aimed
at the design of mucoadhesive controlled release
devices on both macro- and micromolecular level. Our
objective in using bioadhesive controlled drug
delivery devices is to prolong their residence at a
specific site of delivery, thus enhancing the drug
absorption process. These mucoadhesive devices can
protect the drug during the absorption process in
addition to protecting it on its route to the
delivery site.
Publications
|
