PITTSBURGH (Oct. 21, 2019) — Titanium has many properties
that make it a great choice for use in implants. Its low density, high
stiffness, high biomechanical strength-to-weight ratio, and corrosion
resistance have led to its use in several types of implants, from dental to
joints. However, a persistent problem plagues metal-based implants: the surface
is also a perfect home for microbes to accumulate, causing chronic infections
and inflammation in the surrounding tissue. Consequently, five to 10 percent of
dental implants fail and must be removed within 10-15 years to prevent infection
in the blood and other organs.
New research from the University of Pittsburgh’s Swanson
School of Engineering introduces a revolutionary treatment for these infections.
The group, led by Tagbo Niepa, PhD, is utilizing electrochemical therapy (ECT) to
enhance the ability of antibiotics to eradicate the microbes.
“We live in a crisis with antibiotics: most of them are
failing. Because of the drug- resistance that most microbes develop, antimicrobials
stop working, especially with recurring infections,” says Dr. Niepa, author on
the paper and assistant professor of chemical and petroleum engineering at the
Swanson School, with secondary appointments in civil and environmental engineering
and bioengineering. “With this technique, the current doesn’t discriminate as
it damages the microbe cell membrane. It’s more likely that antibiotics will be
more effective if the cells are simultaneously challenged by the permeabilizing
effects of the currents. This would allow even drug-resistant cells to become
susceptible to treatment and be eradicated.”
The novel method passes a weak electrical current through
the metal-based implant, damaging the attached microbe’s cell membrane but not
harming the surrounding healthy tissue. This damage increases permeability,
making the microbe more susceptible to antibiotics. Since most antibiotics
specifically work on cells that are going to replicate, they do not work on
dormant microbes, which is how infections can recur. The ECT causes
electrochemical stress in all the cells to sensitize them, making them more
susceptible to antibiotics.
The researchers hope this technology will change how
infections are treated. Researchers focused their research on Candida albicans (C. albicans), one of
the most common and harmful fungal infections associated with dental implants. But
while dental implants are one exciting application for this new technology,
Niepa says it has other potential applications, such as in wound dressings.
The paper, “Electrochemical Strategy for Eradicating
Fluconazole-Tolerant Candida albicans using Implantable Titanium,” (DOI: 10.1021/acsami.9b09977) was
published in the journal ACS Applied
Materials & Interfaces. It was coauthored by Eloise Eyo Parry-Nweye,
Nna-Emeka Onukwugha, Sricharani Rao Balmuri, Jackie L. Shane, Dongyeop Kim,
Hyun Koo and Tagbo Niepa.
Maggie Pavlick, 10/21/2019
Contact: Maggie Pavlick