Sutures of the future might well be deployed by a portable ink-jet printer according to scientists in the US. University of North Carolina at Chapel Hill researcher Roger Narayan and his team, with a view to finding better ways to close wounds, have been investigating the sticking power of a collection of proteins used by marine mussels to anchor themselves to the seabed.
As anyone who has ever tried to prise a mussel off a jetty or a rock knows only too well, these proteins are extremely powerful adhesives. "They're based around the amino acid DOPA," explains Narayan, "and because they are a naturally-occurring protein mixture they are likely to be much better tolerated by the body than sutures or artificial tissue glues like cyanoacrylate (superglue) which has been used in the past but can cause toxic effects and doesn't break down in the body". But a key question is how to utilise and deploy these sticky molecules to get them into wounds or surgical sites so that they can join tissues together.
Writing in the Journal of biomedical Materials Research B, Narayan and his colleagues may have found the answer - an ink-jet printer head. This uses a vibrating piezo-electric crystal to spit out tiny droplets. The team have found that mixing small amounts of iron ions with the mixture results in a very strong glue, probably by encouraging the mussel proteins to stick to surrounding tissue rather than itself.
"You can foresee hand-held devices in the future that could spray the correct combinations of the glue mixtures onto wound surfaces," says Narayan. "The use of the inkjet technology gives you greater control over the placement of the adhesive. This helps to ensure that the tissues are joined together in just the right spot, forming a better bond leading to improved healing and less scarring."