Biomedical engineers and surgeons at Duke University and UCLA have demonstrated an antibiotic coating that can be applied to orthopedic implants minutes before surgery that eliminates the chances of an infection around the implant.
Antibiotic-releasing Coating Protects Implants
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We’ve shown that a point-of-care, antibiotic-releasing coating protects implants from bacterial challenge, and can be quickly and safely applied in the operating room without the need to modify existing implants,” said Christopher Hart, a resident physician in UCLA Orthopaedic Surgery who helped conduct the experiments.
The new antimicrobial coating is made of two polymers, one that repels water and one that mixes well with water. Both are combined in a solution with an antibiotic of the physician’s choosing and then applied directly to the orthopedic implant by dipping, painting or spraying. When exposed to a bright ultraviolet light, the two polymers couple together and self-assemble into a grid-like structure that traps the antibiotics.
The reaction is an example of “click chemistry,” which is a general way of describing reactions that happen quickly at room temperature, produce only a single reaction product, have an extremely high yield and occur within a single container.
Part of the challenge of treating these infections is that bacteria colonize the surface of the implants themselves. This means that there are no blood vessels flowing through the bacterial colonies to deliver the antibiotics coursing through a patient’s veins. The only recourse is often the removal of the original implant, which is usually the best of what are only bad options.
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This study is a great example of the power of click chemistry in biomedical applications,” said Weixian Xi, now a senior scientist at Illumina who was a postdoctoral researcher at UCLA during the study.
“This ‘smart’ and ‘clickable’ polymeric coating enables protections of implants from bacterial infection and makes a personalized approach possible."
“Our coating can be personalizable because it can use almost any antibiotic,” Segura continued.
“The antibiotic can be chosen by the physician based on where in the body the device is being implanted and what pathogens are common in whatever part of the world the surgery is taking place.”
The researchers have not yet tested their coating on larger animals. Since larger animals—such as humans—have larger bones and need larger implants, there is much more surface area to protect against bacterial infections. But the researchers are confident that their invention is up to the task and plan to pursue the steps needed to commercialize the product.
Source: Duke University