New Antimicrobial Hydrogel Fights ‘Superbugs’
Synthetic polymer gel could be applied to skin infections, wound healing (Jan. 24)
According to a recent report, researchers at IBM Corporation and the Institute of Bioengineering and Nanotechnology in San Jose, Calif., have developed a synthetic antimicrobial hydrogel that can break through diseased biofilms and eradicate drug-resistant bacteria on contact. The gel, which forms spontaneously when heated to body temperature, is the first to be biodegradable, biocompatible, and nontoxic.
If commercialized, the remoldable synthetic hydrogel — composed of more than 90% water — could be applied to creams or injectable therapeutics for skin infections, wound healing, implant and catheter coatings, or even orifice barriers, according to the investigators.
The new research was published in the German journal Angewandte Chemie (Applied Chemistry).
Able to colonize on almost any tissue or surface, microbial biofilms — adhesive groupings of diseased cells present in 80% of all infections — persist at various sites in the human body, especially in association with medical equipment and devices. Microbial biofilms contribute significantly to hospital-acquired infections, which are among the top five leading causes of death in the U.S. and account for up to $11 billion in healthcare spending each year, according to the researchers.
Despite advanced sterilization and aseptic techniques, infections associated with medical devices have not been eradicated. This is due, in part, to the development of drug-resistant bacteria. According to the Centers for Disease Control and Prevention (CDC), antibiotic drug resistance in the U.S. costs an estimated $20 billion a year in healthcare costs as well as 8 million additional days spent in the hospital.
Through the tailoring of polymers, the researchers designed macromolecules that combine water solubility, a positive charge, and biodegradability. When mixed with water and heated to body temperature, the molecules self-assemble, swelling into a synthetic gel that is easy to manipulate. Since this material exhibits many of the characteristics of water-soluble polymers without being freely dissolved, it can remain in place under physiological conditions while demonstrating antimicrobial activity, the researchers say.
When applied to contaminated surfaces, the hydrogel’s positive charge attracts all negatively charged microbial membranes — like powerful gravitation into a black hole. However, unlike most antibiotics and hydrogels, which target the internal machinery of bacteria to prevent replication, the new hydrogel kills bacteria by membrane disruption, thereby precluding the emergence of any resistance.
Source: IBM Corporation; January 24, 2013.