A glass that is biodegradable

Whether in the ground, in water or in the air: glass remains stable for thousands of years. Plastic alternatives, on the other hand, break down into microplastics over time if they are released into the environment. Neither is ideal from an environmental point of view. Now a biodegradable glass is set to minimise the ecological footprint of the material. A team of researchers led by Xuehai Yan from the Chinese Academy of Sciences has presented how in the scientific journal "Science Advances".

The experts use amino acids and short chains of these molecules, known as peptides. They first heat these and then allow them to cool quickly without forming a crystal structure. Instead, an amorphous structure is formed - the essential characteristic of a glass. The biggest hurdle that Yan and his team had to overcome was the heat stability of the starting molecules. Normally, these degenerate at the temperatures required for production. However, Yan and co found a way to protect the molecules from this with the help of chemical modifications, for example by attaching acetyl or benzyloxycarbonyl groups.

The resulting glasses - so far probably only spheres half a centimetre in diameter - were comparable to conventional glass in terms of their properties and processing, the team writes. They can also be processed using 3D printers. Tests have shown that small samples of this glass decompose in compost soil within around nine months. They serve as food for the microorganisms and are thus recycled to a certain extent. The material also showed fundamental suitability in animal experiments: it was broken down over time in the bodies of mice and could therefore be used for implants that dissolve by themselves.

Spectrum of science

We are partners of Spektrum der Wissenschaft and want to make well-founded information more accessible to you. Follow Spektrum der Wissenschaft if you like the articles.