Associate uses eco-conscious engineering to develop prostheses

July 26, 2016

Dr. Frank Ko, a Faculty Associate with the Peter Wall Institute for Advanced Studies, sees endless possibilities in mimicking nature’s extensive use of fibres. He points to his favourite example from the animal kingdom: a spider digests an insect off its web and in order to produce more protein to spin a new web, it then eats that web to absorb and recycle the protein again.

“It’s a very interesting model for eco-conscious engineering”, he says.

While spider silk may be the most compelling natural structure to come to mind, for Dr. Ko, it’s only the start.

“Nature is full of fibrous materials,” he says. “Look at your body, or at a tree, it’s all fibrous material. The structural elements are always fibrous material.”

In fact, it is in the fibres of the human body, and in tree fibres, known as cellulose/lignin, that Dr. Ko’s most promising areas of research lie.

When the human body builds bone, it depends on fibrous materials like collagen to form the scaffolding on which the bone tissue develops. Drawing inspiration from this process, Dr. Ko is developing implants or prostheses that can aid in healing. 

Unlike traditional implants, which are foreign to the body and can cause complications from rejection, these implants can be integrated into body tissues, slowly break down, and even release medicine at the site of injury while defending against infection.

These scaffolds could become a normal part of surgical procedures and burn care– and the material from which they could be derived might seem as surprising as the treatments themselves.

“Canada, of course, has plenty of trees,” explains Dr. Ko, a Tier I Canada Research Chair and Professor in UBC’s Department of Materials Engineering. This super-abundant natural resource– the second-most abundant natural polymer on the planet– is being put to waste; only about two per cent of the lignin we harvest is being put to good use. By extracting the polymer and converting them into carbon nanofibres, Dr. Ko says a larger portion of the lignin could potentially be used in car bodies, electrodes for batteries, ultrahigh sensitive sensors for health monitoring, and even electromagnetic shielding for electronic device applications.

Before the lignin can be put to these diverse uses, it has to be “spun” into a nanofibre, an extremely thin fibre. This spinning increases its surface area, making it more reactive, for use in sensors, for example, and reducing the probability to include defects, which makes it stronger. To produce the nanofibre, the polymer is subjected to an electrical field that overcomes the surface tension of the polymer then teases out a fine filament by solvent evaporation and a whipping motion. The end result is a fibre between 100-500 nanometres (nm), around the size of the smallest known bacterium. Your hair is about 50,000 nm in diameter.

“My work is to add function to this fibre,” he says.

Adding such diverse function to nanofibres means input from an equally diverse number of fields; his multidisciplinary connections help him to explore more potential applications for nanofibres and bring seemingly wild technological ideas into reality. As a Faculty Associate of the Institute, Dr. Ko is part of a multidisciplinary group of researchers at the Advanced Materials and Process Engineering Laboratory (AMPEL) and in laboratories across campus, from which he can glean insights into biology, clinical practice, engineering, and many other disciplines. His work on lignin-based carbon nanofibres has brought him together with new research groups, including the Natural Sciences and Engineering Research Council (NSERC) Biomaterials and Chemicals Network and the Genome Canada team at UBC.

From wearable, flexible electronics for health monitoring to biodegradable, implantable scaffolds for tissue regeneration, Dr. Ko is adding nearly endless functions to fibres. His work also has the potential to reduce the necessity of petroleum products, as many of the naturally-derived fibrous materials made in his lab serve the same purpose as their oil-based counterparts.

As for the future?

Dr. Ko is optimistic: “The future is already here.”