Protein Nanofibres with Defined Properties

Protein fibres are found virtually everywhere in nature and often have outstanding properties such as great stability, biodegradability, and antibacterial effects. Materials scientists from Friedrich Schiller University (FSU) Jena, Germany, have succeeded in recreating them.

"Protein fibres consist of several natural protein macromolecules," explains Prof. Dr. Klaus D. Jandt from the Otto Schott Institute of Materials Research at FSU. "Nature builds these nanomaterials, whose diameter is roughly a 1,000 times smaller than that of a human hair, by way of self-assembly processes." In recent years, Prof. Jandt and his team have succeeded in creating protein nanofibres from the natural proteins fibrinogen and fibronectin, and in controlling their size and structure.

The researchers came up with the idea of combining two different proteins in a self-assembling protein nanofibre in order to create new fibre properties in this way. They used the proteins albumin and haemoglobin. Both these proteins were dissolved in ethanol and then heated to 65 °C. For the first time, this has resulted in the apparently autonomous formation of new hybrid protein nanofibres that contained both proteins. This involves a so-called handshake between the two proteins, meaning that similar sections of both proteins combine to form a fibre. So-called tip-enhanced Raman spectroscopy (TERS) was used to prove the existence of these proteins. "The method’s extreme sensitivity allowed us to identify the different proteins even without special markers, and also permitted their unambiguous classification in close cooperation with Prof. Jandt’s colleagues," says Prof. Deckert from the Leibniz Institute of Photonic Technology in Jena. 

Biomimetic principles for the materials of the future

The researchers from Jena view the creation and proof of the new nanofibres as a breakthrough. The innovative fibres can now be used to build new, larger structures with specific, desired properties that have up until now been impossible to create. Networks made of the new nanofibres are to be used as a novel material for regenerating bone and cartilage in the future. Prof. Jandt is convinced that "this has opened the door for a completely new generation of functional materials for medical engineering, nanoelectronics, sensorics, or optics, all based on natural substances and construction principles."