Scientists at the University of Chicago have found a new use for an ingredient commonly found in herbal tea—malva nuts.
Instead of just being a sore throat remedy, these nuts have been turned into a jelly-like substance called a hydrogel, which can be used in medicine.
The research, published on February 17 in Matter, shows that this natural hydrogel has great potential for wound care, medical monitoring, and even bioelectronics.
A Surprising Discovery in a Cup of Tea
In traditional Chinese medicine, malva nuts—known as Pangdahai—are often soaked in hot water and used as a natural remedy for sore throats.
When placed in water, they expand dramatically, becoming soft and jelly-like. After drinking the tea, people usually throw away the leftover jelly. But PhD student Changxu Sun saw something special in this waste.
“Most people see this as just tea residue, but I saw an opportunity for sustainable biomedical applications,” said Sun, the study’s lead author.
Turning Nuts into Medical Gel
To transform malva nuts into a hydrogel, scientists first crushed the nuts in a blender. Then, they used a centrifuge to separate the soft, water-absorbing part from the hard outer shell.
The soft material was freeze-dried, removing all the water and leaving behind a dry, sponge-like structure. When rehydrated, it turned into a gel.
This hydrogel has many benefits. It is soft, flexible, and holds water well—making it similar to human tissue. Because of these properties, hydrogels are already used in medicine for wound healing, drug delivery, and medical devices like ECG (electrocardiogram) patches. However, this new malva nut hydrogel showed even better performance than commercial ECG patches in tests.
A new, affordable medical solution
The researchers believe this discovery could provide a low-cost medical solution, especially for Southeast Asian countries where malva trees grow naturally.
These nations often struggle with access to medical resources, and using local materials like malva nuts could help create affordable healthcare solutions.
“They’re low-income countries with limited healthcare resources,” Sun explained. “By using a natural material that grows locally, we can create valuable medical products while also supporting their economies.”
This study highlights the potential of plants for medical innovation. Instead of focusing only on their traditional uses, researchers are now exploring how natural materials can help improve healthcare worldwide.
