Researchers in Japan have created a device that spins artificial spider silk that closely matches natural spider silk. The artificial silk gland was able to re-create the complex molecular structure of silk by mimicking the various chemical and physical changes that naturally occur in a spider’s silk gland.
The research: The research team was led by Professor Keiji Numata of the RIKEN Center for Sustainable Resource Science. The findings have been published in Nature Communications in the paper, ‘Replicating shear-mediated self-assembly of spider silk through microfluidics’.
Biomimicry approach: The development of artificial spider silk with properties similar to native silk has been a challenging task in materials science.
- Spider silk is a biopolymer fibre made from spidroins—large proteins with highly repetitive sequences. Within the silk fibres there are beta sheets, which must be aligned properly for the silk fibres to have their unique mechanical properties.
- For this, the precursor spidroin solution—based on recombinant MaSp2 spidroin—was placed at one end of a small rectangular box containing channels and then pulled toward the other end by means of negative pressure. As the spidroins flow through the microfluidic channels, they are exposed to precise changes in the chemical and physical environment. Under the correct conditions, the proteins self-assembled into silk fibres with their characteristic complex structure.
- The scientists discovered that using force to push the proteins through did not work; only when they used negative pressure to pull the spidroin solution could continuous silk fibres with the correct telltale alignment of beta sheets be assembled.
The significance: The ability to artificially produce silk fibres using this method could not only help reduce the negative impact that current textile manufacturing has on the environment, but the biodegradable and biocompatible nature of spider silk makes it ideal for biomedical applications, such as sutures and artificial ligaments.
What they said:
In this study, we attempted to mimic natural spider silk production using microfluidics, which involves the flow and manipulation of small amounts of fluids through narrow channels. Indeed, one could say that that the spider’s silk gland functions as a sort of natural microfluidic device.
— Keiji Numata
Professor, Department of Material Chemistry
Kyoto University
