Vegan “spider silk” developed by Cambridge scientists could replace single-use plastic
A novel material called “vegan spider silk” was developed by researchers at the University of Cambridge and could be a long-term replacement for single-use plastic.
Human dependence on plastic remains one of the greatest problems facing mankind as millions of tons of waste are produced every year.
Tiny fragments, called microplastics, have been found in the Alps and in the Himalayas, as well as on the floor of the Mariana Trench in the Pacific Ocean and in Antarctica.
As a result of this increasingly pressing problem, there is now a strong desire to find ways to break down existing plastic and create packaging that will replace the ubiquitous oil-based plastics.
Cambridge researchers looking to fix the second problem took inspiration from spider silk, one of nature’s strongest and most remarkable materials.
They found that the molecular bonds holding spider silk together, while weak, are robustly reinforced by a high density of other bonds.
But animal proteins have their own set of difficulties and problems when it comes to ethical commercial exploitation.
Dr. Tuomas Knowles of the Yusuf Hamied Department of Chemistry at Cambridge is an expert on protein folding and usually studies it to learn more about the effects of misshapen proteins on human health.
But his expertise showed what spider silk is that gives it immense strength. The team of scientists was then able to apply this to a vegetable protein obtained from soy.
Soy is a common crop and its waste is readily available, but its proteins are very different from those of spider silk. Dr. Knowles and his team were able to remove the soy protein and transform it into the form of spider silk.
“Since all proteins are made up of polypeptide chains, under the right conditions we can get plant proteins to organize themselves like spider silk,” said Dr. Knowles.
This method, published in the journal Nature Communications, allows materials scientists to avoid working with animal proteins.
“In a way, we developed ‘vegan spider silk’ – we made the same material without the spider,” said study co-author Dr. Marc Rodriguez Garcia. He’s also the head of research and development at a company called Xampla that is working on commercializing the product.
Xampla says it will launch a range of bags and capsules by the end of 2021, which will replace products like dishwasher tablet packaging and laundry capsules.
This plastic substitute is not only made from sustainable sources, but can also be left on the compost heap at home and does not require any special treatment to be recycled.
As with all new technologies, cost is the main problem faced with widespread adoption of the technology.
The two-step process of transforming the proteins into the desired guse includes acidification, application of sound waves and high temperatures, whereby the manufacturing costs correspond to those of other natural plastic alternatives.