Pitcher Plants Inspire Kidney Stone Diagnostic

Urine contains an abundance of dissolved salts and minerals such as calcium and uric acid. These can form crystals, which can grow in size, creating a very painful problem. Stanford and Penn State researchers have created a new diagnostic test inspired by pitcher plants — carnivorous plants with jug-shaped leaves to trap insects.

“There are many aspects we can learn from nature and our environment, and our research is an example how biomedical engineers can make good use of it,” said Pak Kin Wong, the principal investigator of the study, published recently in Science Advances.

The team developed a biomimetic kidney stone detection system they called slippery liquid-infused porous surface (SLIPS)-LAB. The device uses surface tension forces to draw urine droplets easily through super-smooth channels, allowing a carefully-controlled diagnostic chemical reaction to occur. This innovation bears many similarities to the pitcher plants’ slick, liquid-infused, micro-textured rims that cause unsuspecting insects to slide right into their vessels containing harsh digestive enzymes.

Understanding the nature of kidney stone crystals is critical a critical first step in preventing them from coming back. Chemical analysis reveals that most of these stones are made of either calcium oxalate or calcium phosphate. Not drinking…