Momentum - The Magazine for Virginia Tech Mechanical Engineering Vol. 2 No. 4 Winter 2017 | Page 22

STORY BY EMILY ROEDIGER
BIOMEDICAL ENGINEERING & MECHANICS
Study takes unique approach to new
generation of smart drug delivery carriers
Imagine a tiny capsule, smaller than the tip of
a needle, that could be programmed to release
medicine at a specific location in your body and
is inexpensive, easy to make, and more effective
than traditional pharmaceuticals. dent in Virginia Tech’s engineering mechanics
program and the study’s lead author, described
the research as an important first step in using
shape-memory polymers to design and optimize
efficient drug delivery systems for human use.
In addition, after delivering its medical con-
tents, the capsule disappears because it can be
safely absorbed into the bloodstream. “With the help of ultrasound, these systems
can deliver drugs in a controlled manner at the
desired target location over a prolonged period
of time, something that has been very difficult
to do in the field of drug delivery mechanisms,”
said Bhargava. “Shape-memory polymers give us
an advantage because they’re flexible, biode-
gradable, and cost-effective. They’re also easy to
manufacture.”
Such a method of drug delivery could better
treat some of the world’s most devastating
illnesses with drugs that are cheaper, more ac-
cessible, and perform better in the human body.
A Virginia Tech research team is one step
closer to realizing that vision. Biomedical engi-
neering and mechanics and mechanical engi-
neering faculty and students have spent the past
year testing the viability of using a unique class
of designed materials, coupled with a surprising
trigger, to build smarter drug delivery systems.
Their research, published in RSC Advances,
outlines a proof of concept for using focused
ultrasound waves to activate shape-memory
polymers. Most recently gaining attention for
their use in designing biocompatible devices,
shape-memory polymers can be used to deliver
drugs inside the human body.
Aarushi Bhargava, a second-year Ph.D. stu-
Shape-memory polymers are a class of smart
materials that have the ability to return from
a deformed, temporary shape to their original
permanent shape when subjected to an external
stimulus, such as light or heat.
In this project, a conceptual framework for
designing a shape-memory polymer container is
loaded with drug particles in its original shape,
heated, and deformed to its temporary shape.
This temporary shape effectively packages the
drug particles inside a tiny capsule-like container.
When the capsule reaches its desired location
within the body, it undergoes shape recovery
through exposure to focused ultrasound and
Shape-memory polymers can be
transformed from a permanent shape
to a deformed, temporary shape when
heated. This temporary shape pack-
ages drug particles for delivery inside
the human body. When the package
reaches a desired location, focused
ultrasound waves cause the package
to return to its permanent shape, a
process that releases the loaded drug
particles into the body.
MOMENTUM
WINTER'17

PAGE 22