Next time you catch a slug meandering its way across your prize lettuces, think about this: that slimy trail could be the key to life-saving technology for healing damaged tissue, such as in beating hearts.
Inspired by creatures that secrete sticky substances with unique water-repelling, adhesive properties, researchers in the US have developed a type of glue that they hope one day will replace sutures and staples and keep beating hearts securely sealed following invasive surgery.
The team, from Boston Children's Hospital, Brigham and Women's Hospital (BWH), and Massachusetts Institute of Technology (MIT), write about their work in a recent issue of Science Translational Medicine.
One group that could benefit greatly from such a solution is children born with a heart defect, such as a hole in the heart. Currently, they have to undergo highly invasive procedures that are complicated by the fact it is not easy to secure devices safely inside the heart.
Sutures take too long to stitch and can overly stress fragile heart tissue. Plus, the clinical adhesives currently available are either too toxic or do not have enough sticking power in blood or in the dynamic environment of a beating heart.
Co-senior author of the study, Dr. Jeffrey Karp, of the Division of Biomedical Engineering, in BWH's Department of Medicine, says:
"About 40,000 babies are born with congenital heart defects in the United States annually, and those that require treatment are plagued with multiple surgeries to deliver or replace non-degradable implants that do not grow with young patients."
Adhesive keeps biodegradable patches securely in place inside beating heart
In their pre-clinical study Dr. Karp and colleagues tested the new glue on pig hearts.
The bio-inspired adhesive can rapidly attach biodegradable patches inside a beating heart. The patches can be placed exactly where congenital holes in the heart occur, such as with ventricular heart defects.
Slug on growing salad leaves
Researchers have created a type of glue inspired by creatures that secrete sticky water-repellant adhesive substances, such as slugs, that they hope could be used to seal damaged tissue.
The researchers developed the material based on properties similar to those secreted by creatures in nature - viscous and water-repellent, enabling them to stick to surfaces under wet and dynamic conditions.
When they used the adhesive - which is activated within seconds with the help of UV light - with patches that are biodegradable, elastic and biocompatible, they found they could keep them securely attached in pig hearts even under conditions of increased heart rates and blood pressure.
Unlike current surgical adhesives, the new glue has a strong sticking power that persists in the presence of blood, and even in active environments, and was strong enough to hold tissue and patches onto heart tissue equivalent to suturing.
And with the added benefit of being biodegradable and biocompatible, nothing foreign or toxic stays in the patient's body.
Glue should provide surgeons with new, simpler technology for tissue reconstruction
Co-senior author Dr. Pedro del Nido, chief of cardiac surgery, Boston Children's Hospital, says:
"This adhesive platform addresses all of the drawbacks of previous systems in that it works in the presence of blood and moving structures.
It should provide the physician with a completely new, much simpler technology and a new paradigm for tissue reconstruction to improve the quality of life of patients following surgical procedures."
The adhesive technology has been licensed to Gecko Biomedical, a start-up company based in Paris. They expect to bring it to market within 2-3 years.
Funds from Boston Children's Hospital and the National Institutes of Health helped finance the study.
In 2013, the Institute of Chemical Engineers gave Brigham and Women's Hospital their Innovative Product of the Year Award for their development of a microneedle patch that seals wounds because on contact with wet tissue it swells and creates a mechanical lock, which minimizes tissue damage.
The microneedle patch was inspired by a gut-clinging worm with a proboscis that swells. The worm, called Pomphorhynchus laevis, is found in freshwater crustaceans.