Cambridge, Massachusetts, USA – 10 September 2025
In a major step forward for sustainable materials, researchers at Harvard University have developed a groundbreaking new process to recycle protein-rich waste like human hair and wool without using the harsh, high-heat chemical processes of the past. The discovery, which sheds new light on the fundamental chemistry of proteins, could pave the way for a new biomaterials industry.
The world’s waste problem is a growing concern, and hair—from barbershops, salons, and even homes—is a significant part of that. Millions of tons of protein-rich waste like hair, feathers, and wool are produced annually and end up in landfills. Now, a team at the Harvard John A. Paulson School of Engineering and Applied Sciences (SEAS) has found a gentle and more sustainable way to recycle this material, turning a waste stream into a valuable resource.
Headlines:
* A Greener Way to Recycle Keratin: Harvard researchers have identified the underlying chemistry of how a salt solution can de-nature proteins like keratin, leading to a new, more sustainable recycling method that avoids harsh chemicals.
* From Waste to Valuable Material: The new process can be used to break down hair and other protein waste, which can then be reformed into a variety of low-cost, eco-friendly materials, potentially serving as a new alternative to traditional plastics.
* The Role of Water, Not Just Salt: The researchers discovered that a concentrated lithium bromide solution works not by directly binding to the protein molecules but by changing the structure of the surrounding water molecules, allowing the proteins to naturally unfold.
* A Reversible and Reusable Process: The same salt mixture can be recovered and reused, making the entire recycling process more efficient and environmentally friendly.
* Applications from Tissue Engineering to Textiles: The new method could have wide-ranging applications, from creating sustainable materials for the textile industry to providing a reliable source of protein for tissue engineering and other medical fields.
The new method, which is detailed in a paper published in the journal Nature Communications, centers on a surprising discovery about how a common salt compound, lithium bromide, interacts with keratin. Scientists had previously believed that the salt directly bonded with the proteins to break them down. However, the Harvard team, led by Professor Kit Parker and research associate Hangbo Yang, found that the salt alters the water molecules around the proteins. This subtle but crucial change causes the proteins to unfold on their own, a process that is far less damaging and more energy-efficient than traditional methods.
The researchers demonstrated that the extracted keratin can form thick, shapeable gels that solidify almost instantly when placed back in water. This property makes it easy to separate and manipulate the material, opening up possibilities for a wide range of products. The recovered protein can be used to create new materials, such as an alternative to wool or even new types of plastics, laying the foundation for a new circular economy for protein waste.
This breakthrough is a significant development in the field of biomaterials and could have a profound impact on multiple industries. By turning a massive waste problem into a valuable resource, the Harvard team has not only created a more sustainable recycling process but has also provided a new path for innovators to create products that are both high-performing and environmentally responsible.
