Researchers develop novel drug delivery system

Jan 31, 2012

Long duration, controllable drug delivery is of wide interest to medical researchers and clinicians, particularly those seeking to improve treatment for patients with chronic pain or to prevent cancer recurrence after surgery. Now a team of researchers led by Boston University Biomedical Engineer and Chemist Mark Grinstaff has developed a unique material and drug delivery mechanism that could pave the way for implants that release a drug at a designated rate for months.

The system consists of a biocompatible, highly porous, three-dimensional containing a selected drug and a volume of air that slows from surrounding water. As water seeps into the material, it displaces the air, gradually releasing the drug.

"The idea was to create a 3D material that has throughout and air trapped within," said Grinstaff, who developed the material in conjunction with BU PhD student Stefan Yohe and Dr. Yolanda Colson, a Brigham and Women's Hospital thoracic surgeon and lung cancer specialist. "If we can slow the penetration of water into the structure, it will slow the release of the drug."

To prevent water from flooding the structure and causing an immediate release of the drug, Grinstaff and his colleagues designed the air-filled, mesh-like material to be "superhydrophobic"—so water-resistant that droplets of water barely touch the surface, forming beads similar to those that appear on a freshly waxed car. They produced the porous polymer mesh using a process called electrospinning, which overlays micron-sized fibers upon one another.

To control the rate of drug release, they adjusted chemical and physical properties of the material so that the entrapped air is loosely or tightly held. The more tightly held the air is within the structure, the harder it is for water to displace it, the slower the release, and the longer the treatment duration.

Loaded with a widely used anti-cancer drug called SN-38 in in vitro experiments, the polymer mesh and internal air pocket proved to be robust and effective against lung cancer cells in solution for more than 60 days, indicating its suitability for long-term . Grinstaff and his collaborators next plan to conduct a series of in vivo experiments to evaluate the system's efficiency and potential clinical effectiveness—a critical preliminary step before initiating clinical trials.

Supported by the National Institutes of Health, The Wallace H. Coulter Foundation, the Center for Integration of Medicine & Innovative Technology and Boston University, this research was originally sparked by the Grinstaff group's ongoing investigation of potential therapies for recurring , and interest in the use of new materials and procedures to deliver drugs over the course of months.

"Many researchers are advancing new drug delivery systems, and several others are designing superhydrophobic materials, but we're combining these disciplines to see if we can open up new doors and enable more effective treatments for a wide range of diseases," said Grinstaff.

The researchers detailed their novel drug delivery system in the January 16 online edition of the Journal of the American Chemical Society.

Explore further: Structure of sodium channels different than previously believed

add to favorites email to friend print save as pdf

Related Stories

Silk microneedles deliver controlled-release drugs painlessly

Dec 21, 2011

Bioengineers at Tufts University School of Engineering have developed a new silk-based microneedle system able to deliver precise amounts of drugs over time and without need for refrigeration. The tiny needles can be fabricated ...

Recommended for you

Breakthrough points to new drugs from nature

Apr 16, 2014

Researchers at Griffith University's Eskitis Institute have developed a new technique for discovering natural compounds which could form the basis of novel therapeutic drugs.

World's first successful visualisation of key coenzyme

Apr 16, 2014

Japanese researchers have successfully developed the world's first imaging method for visualising the behaviour of nicotine-adenine dinucleotide derivative (NAD(P)H), a key coenzyme, inside cells. This feat ...

User comments : 0

More news stories

Hackathon team's GoogolPlex gives Siri extra powers

(Phys.org) —Four freshmen at the University of Pennsylvania have taken Apple's personal assistant Siri to behave as a graduate-level executive assistant which, when asked, is capable of adjusting the temperature ...

Deadly human pathogen Cryptococcus fully sequenced

Within each strand of DNA lies the blueprint for building an organism, along with the keys to its evolution and survival. These genetic instructions can give valuable insight into why pathogens like Cryptococcus ne ...

Researchers discover target for treating dengue fever

Two recent papers by a University of Colorado School of Medicine researcher and colleagues may help scientists develop treatments or vaccines for Dengue fever, West Nile virus, Yellow fever, Japanese encephalitis and other ...