Dalem Roswell Sipin

Researchers from the University of California, Irvine, in collaboration with Japanese scientists, have transformed human urine into a valuable mineral that is used in bone and dental implants. 



The study published in May 2025, entitled “Cost-effective urine recycling enabled by a synthetic osteoyeast platform for production of hydroxyapatite,” uses yeast to break down urine into a biocompatible calcium phosphate mineral, hydroxyapatite (HAp).

“Inspired by the biological mechanisms of bone-forming cells, we develop a synthetic yeast platform, osteoyeast, which uses enzymes to break down urea and increase the pH of the surrounding environment,” the scientists said.

HAp is not only utilized in the field of medicine as a mineral for implants but also in archaeological restoration and construction materials.

However, the synthesis of HAp is costly and dangerous, as the chemical reaction in producing HAp may yield harmful byproducts. 

According to the researchers, their process of synthesis is not only revolutionary but also sustainable and cost-effective. 

"This process to yield hydroxyapatite, or bone mineral, takes less than one day," Kisailus, a  scientist, said. 

Furthermore, the US military's Defense Advanced Research Projects Agency (DARPA) funded the study as part of the US Bio-inspired Restoration of Aged Concrete Edifices (BRACE) program, which aims to add self-repairing capabilities of living organisms into construction materials such as concrete. 

With this breakthrough, the scientists are now using 3D printing for hydroxyapatite-based materials in producing medical implants, biodegradable plastics, construction materials, and energy devices.