Retein

Learning from nature to filter minerals from polluted water

Water scarcity is already a serious issue for roughly half the world’s population, according to the IPCC. Just 0.5% of water on Earth is usable freshwater, and we currently use 70% of it for agriculture. With a growing global population, the pressure on this resource will increase at the same time as climate change is altering weather patterns, causing drought in some areas and flooding in others. These extremes exacerbate many forms of water pollution, while industry continues to pollute freshwater ways.

Swedish firm Retein, a spin out from the Chalmers University of Technology, is developing potentially transformational, energy-efficient biotech that could help clean polluted water, recovering valuable resources, such as lithium and other rare earth minerals, in the process.

Using nature as a template – a technique known as ‘biomimicry' – Retein has found a way to isolate and embed a protein called aquaporin in a membrane to create an efficient filter. Aquaporin functions in nature as a highly precise channel for water passage – a kind of gateway across the cell membrane that equips the cell to selectively recover resources based on its needs.

Conventional polymer membranes augmented by these aquaporins can precisely filter out impurities and retain materials that would otherwise go to waste. Aquaporins are normally incredibly fragile, but Retein has found a way to stabilise them with a silica-based shell that improves their durability without changing their functionality.

Retein’s technology is important as current practices in wastewater management do not recover sufficient nutrients, resulting in a host of environmental problems. If scaled, the startup’s proprietary method could be a gamechanger.

For more information, please visit the Retein website.