Getting the right materials

NUI GALWAY:N EW MATERIALS to repair damaged hearts, regenerate severed spinal cords, restore blood flow to limbs, and the smart delivery of drugs to the exact site in the body where they are required are just a few of the lines of research ongoing at the Network of Excellence for Functional Biomaterials (NFB) based at NUI Galway.

The Science Foundation Ireland supported NFB is a group of research scientists based at the National Centre for Biomedical Engineering Science at the university. Its core service centres on academic research and development, with much of its work also facilitating the development of collaborations with the medical device industry both nationally and internationally through technology transfer initiatives.

Biomaterials, which may be natural, synthetic or a combination of both, are placed within the body for therapeutic reasons. Their effectiveness can be greatly increased by combining them with therapeutic agents such as genes, growth factors and other biomolecules. The overall objective of the NFB is to bring a critical mass of expertise together on a single platform to develop the next generation of biomaterials.

The science of biomaterials is very young, only about 30 years old, and this means that the work of the NFB is very much at the leading edge internationally.

“Biomaterials are any materials that can be used in a biological system and that engage with it,” says NFB director Prof Abhay Pandit. “They have been around a very long time. Egyptian mummies have been found to have gold teeth, for example, and we have been using stainless steel and other materials to treat broken bones for years. But the science of biomaterials is only 30 years old and the reason for that is simple; people started asking why the materials being used were failing.”

According to Pandit this was because the materials were designed for function rather than biology. “In the past 15 years, materials scientists have begun to better understand biological systems and we are now designing materials which can either engage with or fool the body.”

This need to fool the body is due to rejection and other problems associated with implants and medical devices.

“Devices perform their function for a period of time. Take a heart valve, for example. You tend to see calcification of artificial valves after about 10 years. This was okay years ago when we had shorter life expectancies, but with people living longer today it is not good enough. The design life of many devices is no longer appropriate.”

NFB is continuously developing new technologies to deliver therapeutic genes and other biomolecules to target specific sites within the body. These include coatings for medical devices, tissue repair scaffolds and programmable nanospheres which carry therapeutic agents to a specific location via the bloodstream. These technological platforms have applications linked to cardiovascular disease, intervertebral disc degeneration, spinal cord and peripheral nerve damage, epidermolysis bullosa, osteochondral defects, wound healing, hernia and thoracic wall defects, staple line reinforcement and adipose tissue regeneration.

There are four main areas of research – musculoskeletal, neural regeneration, soft tissue repair, and cardiovascular regeneration. “In the cardiovascular area we are developing a cardiac patch to repair damaged heart tissue,” says Pandit. “We are also developing a product to treat chronic aschaemia in limbs by restoring the blood supply. In many instances this condition results in amputation.”

In the neural area the team is working on the development of a material that degrades naturally in the body, can be inserted into the spinal column and promotes the regeneration of the spinal cord. Also under development are novel therapies for multiple sclerosis and Parkinson’s disease.

These therapies involve new drug delivery systems. “We have developed capsules which are a cargo system to carry the molecules to where they are needed,” says Pandit. “The capsules degrade in the body and release the molecule when it is required.”

Research in soft tissue repair at NFB focuses on biomaterials for reconstructive surgery and chronic wound healing as well as methods to treat the wounds in conditions such as Recessive Dystrophic Epidermolysis Bullosa.

In the musculoskeletal area the research is focused on the regeneration of intervertebral spinal discs, bone regeneration, prosthetics development and tendon and ligament regeneration.

A number of industrial partners are already involved with the NFB and these collaborations are aimed at the development of innovative biomedical based platforms and bring biomaterial inspired technologies to the bedside. “We work closely with the locally based medical device industry,” says Pandit. “The industry is huge here in Ireland and is very important to the economy. That’s why we have to be very attentive to the industry and make sure it has access to top-notch research. However, it will take a long time for our research to be translated into medical devices. The translation process takes about seven or eight years because we have to be sure of the success of the technology and it has to go through full clinical trials and so on. We are very hopeful that in future years our research will be used in medical devices manufactured here in Ireland.”