Nanofibre thread spun into surgical sutures

A nanofibre thread designed for use in medical sutures could enter clinical trials later this year in surgery to repair injured shoulders.

The thread, known as Bioyarn, has been developed by researchers at Oxford University. They hope to begin testing it in surgery to repair torn tendons in the rotator cuff. Around 40 per cent of surgeries on this painful condition fail, and the researchers hope the thread will improve the success rate.

Nanoscale fibres are extremely porous and have a very high surface area by volume, making them excellent candidates for use in surgical sutures, tissue scaffolds and wound dressings, according to Nikolaos Chalkias, senior technology transfer manager at Isis Innovation, Oxford University’s technology commercialisation company.

But despite their potential, until now there has been no way to reliably produce very long filaments of the material, which would allow it to be woven into different types of fabric or medical device.

So the researchers have developed a technique to spin the fibres onto a moving wire, allowing them to stretch out very long strands. “We can effectively make a ball of electrospun yarn,” said Chalkias.

The technology is based on conventional electrospinning, in which a solution is drawn through an electrically-charged hollow needle onto a grounded target, in this case the wire. As the solution is drawn towards the wire, it stretches out into a very fine fibre.  Then, as the wire moves past the needle, the material attaches to it and is drawn along with it.

“Since the fibre does not stick fast to the wire, it can simply be peeled off using an automated machine,” said Chalkias. “We can then weave that thread into fabrics, or into medical device materials like patches.”

Thanks to their nanoscale dimensions, these patches can mimic the extracellular environment within human tissue, meaning they should help support cell growth, said Chalkias.