Researchers say a lab-made, plant-based material that mimics spider silk could replace single-use plastics in many consumer products.
The material, which was developed in a University of Cambridge study, uses a new, energy-efficient approach to assemble plant proteins at the molecular level into a material that mimics silk.
This is done by mimicking the structures found in spider silk – one of the strongest materials in nature – using soy protein isolate, a protein with an entirely different structure.
Professor Tumas Knowles said, “Since all proteins are made up of polypeptide chains, under the right conditions we can self-assemble plant proteins like spider silk.”
He said that when spiders weave their webs, the silk proteins dissolve in an aqueous solution that assembles into a strong fiber through the spinning process, which requires minimal energy.
Similar to the spider, the researchers had to find a way to dissolve the plant proteins so that they could be reassembled to mimic the properties of spider silk.
Unfortunately, plant proteins are poorly soluble in water, but researchers have developed an environmentally friendly and energy efficient method for isolating soy protein in a mixture of water and acetic acid. Once the process is complete, and the solvent is removed, the soy protein isolate is reassembled as a water-insoluble, plastic-like film.
Ayaka Kamada, PhD candidate and first author on the paper, said: “Little is known about the self-assembly of proteins, and it is exciting to learn that by filling this knowledge gap we can find alternatives to single-use plastics. “
The study showed that the material had strengths comparable to high performance engineering plastics such as low-density polyethylene. But unlike most plastic films, the new material can be made at home, as no chemical modifications were made to its natural building blocks, and no toxic ingredients were added.
The new product will be marketed by the University of Cambridge spin-out Xampla, which focuses on developing replacements for single-use plastics and microplastics. Later this year, the company will introduce several single-use products to replace the plastic used in laundry detergent capsules and dishwasher tablets.
Mark Rodrigues García, postdoctoral researcher, co-author of the study and head of research and development at Zampla, said: “Other researchers are working directly with silk materials as a replacement for plastics, but they are still an animal product. .
“In a way we have come up with ‘vegan spider silk’ – we have made a single material without the spider”
He continued: “It’s exciting to be a part of this journey. Plastic pollution is a big, big issue in the world, and we’re in a fortunate position to be able to do something about it.”
Credit: www.independent.co.uk /