Some materials, however, are easier to spin in this way than others, for if the molecules do not stick together, the liquid stream will break up. And, until now, that has been true of bovine serum albumin. The molecules of this protein are more or less globular, and are held in that shape by internal cross-links between different parts of the amino-acid chain of which the protein is composed. That discourages them from forming fibres. Though electrospun bovine serum albumin does not actually break up into droplets, the resulting threads have been so short and irregular as to be useless.

What Zussman and his colleagues have managed to do is break the internal bonds in the protein molecules by mixing them with a chemical called beta-mercaptoethanol.

The result, as they report in Biomacromolecules, is that they can spin bovine serum albumin into long, even fibres that are perfect for creating both suture threads and thick mats similar to conventional wound dressings, but on a small scale. Not only are these threads and mats readily accepted by the body, the albumin of which they are composed has glue-like properties, which helps to stick torn tissues together. The consequence is that sutures made with these new threads are expected to reduce the scarring left when the stitches are removed. More significantly, that they do not provoke inflammation means they might be used to repair the wounds of patients with conditions such as diabetes, in which chronic skin infections often get in the way of healing when normal stitches are used. And that would be a real advance on polypropylene and sheep’s gut.