Opens new applications for the nearly 5.5 billion pounds of PET bottles
and jars available annually for recycling
TORONTO, Dec. 9, 2013 /CNW/ - Researchers from IBM (NYSE: IBM) and the Institute of Bioengineering and Nanotechnology have made a
nanomedicine breakthrough in which they converted common plastic
materials like polyethylene terephthalate (PET) into non-toxic and
biocompatible materials designed to specifically target and attack
fungal infections. This research was published today in the
peer-reviewed journal, Nature Comm.
Watch how IBM Research 'ninja polymers' will change how we fight
drug-resistant superbugs: http://www.research.ibm.com/articles/nanomedicine.shtml
Over a billion people are affected by fungal infections every year,
ranging in severity from topical skin conditions like athlete's foot to
life-threatening fungal blood infections. The infection is more likely
to occur when the body's immune system is compromised due to an illness
like HIV/AIDS, cancer or when receiving antibiotic treatment.
There is a pressing need to develop efficient and disease-specific
antifungal agents to mitigate this growing drug resistance problem.
Traditional antifungal therapeutics need to get inside the cell to
attack the infection but have trouble targeting and penetrating the
fungi membrane wall. Also, since fungi are metabolically similar to
mammalian cells, existing drugs can have trouble differentiating
between healthy and infected cells.
Recognizing this, IBM scientists applied an organic catalytic process to
facilitate the transformation of PET, or waste plastic from a bottle,
into entirely new molecules that can be transformed into antifungal
agents. This is significant as plastic bottles are typically recycled
by mechanical grounding and can mostly be reused only in secondary
products like clothes, carpeting or playground equipment.
How it Works
These new antifungal agents self-assemble through a hydrogen-bonding
process, sticking to each other like molecular Velcro in a polymer-like
fashion to form nanofibers. This is important because these antifungal
agents are only active as a therapeutic in the fiber or polymer-like
This novel nanofiber carries a positive charge and can selectively
target and attach to only the negatively-charged fungal membranes based
on electrostatic interaction. It then breaks through and destroys the
fungal cell membrane walls, preventing it from developing resistance.
According to Dr Yi Yan Yang, Group Leader, IBN, "The ability of these
molecules to self-assemble into nanofibers is important because unlike
discrete molecules, fibers increase the local concentration of cationic
charges and compound mass. This facilitates the targeting of the fungal
membrane and its subsequent lysis, enabling the fungi to be destroyed
at low concentrations."
Leveraging IBM Research's computational capabilities, the researchers
simulated the antifungal assemblies, predicting which structural
modifications would create the desired therapeutic efficacy.
"As computational predictive methodologies continue to advance, we can
begin to establish ground rules for self assembly to design complex
therapeutics to fight infections as well as the effective
encapsulation, transport and delivery of a wide variety of cargos to
their targeted diseased sites," said Dr. James Hedrick, Advanced
Organic Materials Scientist, IBM Research - Almaden
The minimum inhibitory concentration (MIC) of the nanofibers, which is the lowest concentration that
inhibits the visible growth of fungi, demonstrated strong antifungal activity against multiple
types of fungal infections. In further studies conducted by Singapore's
IBN, testing showed the nanofibers eradicated more than 99.9% of C. albicans, a fungal infection causing the third most common blood stream infection
in the United States, after a single hour of incubation and indicated no resistance after 11
treatments. Conventional antifungal drugs were only able to suppress
additional fungal growth while the infection exhibited drug resistance
after six treatments.
Additional findings of this research indicated the nanofibers
effectively dispersed fungal biofilms after one-time treatment while
conventional antifungal drugs were not effective against biofilms.
The in vivo antifungal activity of the nanofibers was also evaluated in a mouse
model using a contact lens-associated C. albicans biofilm infection. The nanofibers significantly decreased the number of
fungi, hindered new fungal structure growth in the cornea and reduced
the severity of existing eye inflammation. These experiments also
showed mammalian cells survived long after incubation with the
nanofibers, indicating excellent in vitro biocompatibility. In addition, no significant tissue erosion is
observed in the mouse cornea after topical application of the
"A key focus of IBN's nanomedicine research efforts is the development
of novel polymers and materials for more effective treatment and
prevention of various diseases," said Professor Jackie Y. Ying, IBN
Executive Director. "Our latest breakthrough with IBM allows us to
specifically target and eradicate drug-resistant and drug-sensitive
fungi strains and fungal biofilms, without harming surrounding healthy
The IBM nanomedicine program - which started in IBM's Research labs four years ago with the mission
to improve human health - stems from decades of materials development
traditionally used for semiconductor technologies. This advance will
expand the scope of IBM and the Institute of Bioengineering and
Nanotechnology's collaborative program, which already includes recent
breakthroughs in fighting diseases ranging from breast cancer to MRSA.
This allows the scientists to simultaneously pursue multiple methods
for creating materials to improve medicine and drug discovery.
SOURCE: IBM Canada Ltd.