New material to destroy hospital superbugs

By Mark Waghorn via SWNS

A smart, germ-killing coating that destroys hospital superbugs has been created by scientists.

It fights infections transmitted through catheters, breathing tubes and other medical devices - without the need for antibiotics.

The World Health Organisation (WHO) has identified drug resistance as one of the biggest threats to mankind.

Senior author Professor Richard Kaner, of the University of California, Los Angeles, said: "The modified surfaces exhibited robust resistance against microorganisms and proteins, which is precisely what we sought to achieve.

"The surfaces greatly reduced or even prevented biofilm formation. And our early clinical results have been outstanding."

Superbugs kill thousands of patients each year. Infection-related complications are estimated to claim around 100,000 lives in the US, annually.

About two-thirds of cases can be traced back to harmful microbes that grow freely on surgical implants such as stents, heart valves and pacemakers.

The protective cover tested in both laboratory and clinical settings could help improve safety - and save billions of dollars in medical costs.

It involves depositing a thin material on the surface which has both positive and negative charges - known as a 'zwitterionic.'

The layer is permanently bound to the underlying substrate using ultraviolet light irradiation.

The resulting barrier prevents bacteria and other potentially harmful organic materials from adhering to the surface - and causing infection.

In experiments, the treatment reduced biofilm growth of microbial strains including bacteria, fungi and proteins by more than 80 percent — and in some cases 93 percent.

Further trials among 16, long-term patients found using a surface-treated catheter reduced urinary tract infections.

Ten described their condition as "much" or "very much" better and 13 preferred it to conventional latex and silicone options after the study ended.

The modified device is the first product made by a company Prof Kaner founded out of his lab, called SILQ Technologies Corp.

It has been cleared for use by the US Food and Drug Administration.

Prof Kaner said: "One patient came to UCLA a few weeks ago to thank us for changing her life - something that, as a materials scientist, I never thought was possible.

"Her previous catheters would become blocked after four days or so. She was in pain and needed repeated medical procedures to replace them.

"With our surface treatment, she now comes in every three weeks, and her catheters work perfectly without encrustation or occlusion - a common occurrence with her previous ones."

Such problems are illustrative of the issues plaguing other medical devices. Once inserted they can become breeding grounds for bacteria and harmful biofilm growth,

The pathogenic cells pumped out by these highly resilient biofilms then cause recurring infections in the body, he said.

In response, medical staff routinely give strong antibiotics to patients using these devices.

The short-term fix poses a longer-term risk by creating life-threatening, antibiotic-resistant 'superbug' infections.

The more widely and frequently antibiotics are prescribed the more likely bacteria are to develop resistance to them, explained Prof Kaner.

A landmark 2014 report by the WHO recognized this overuse as an imminent danger to public health.

Officials called for an aggressive response to prevent 'a post-antibiotic era in which common infections and minor injuries which have been treatable for decades can once again kill.'

It could return medicine to the 'dark ages' - before the days of penicillin - when common infections became killers.

Prof Kaner said: "The beauty of this technology is it can prevent or minimize the growth of biofilm without the use of antibiotics.

"It protects patients using medical devices — and therefore protects all of us — against microbial resistance and the proliferation of superbugs.”

The coating's polymers are extremely biocompatible and are thoroughly absorbant - forming a hydration barrier that stops microbes from sticking to surfaces, said Prof Kaner.

The technology is highly effective, non-toxic and cheaper than antibiotic- or silver-infused alternatives.

It also has potential for non-medical applications such as extending the lifetimes of water-treatment devices and improving lithium-ion battery performance.

The study is in Advanced Materials.