Kidney Stones and Urine Testing Analysis

An improved urine-testing system for people suffering from kidney stones inspired by nature and proposed by researchers from Penn State and Stanford University may enable patients to receive results within 30 minutes instead of the current turnaround time of a week or more.

Metabolic testing of a kidney stone patient's urine to identify metabolites such as minerals and solutes that cause stones to form is key for preventing future ones. This testing is currently done by requiring the patient to collect their urine over a 24-hour period in a large container. The container is then sent to a lab for analysis and the results normally come back in 7 to 10 days.

"The lengthy process, cumbersome collection procedure and delay in obtaining the results render 24-hour urine testing to be underutilized in clinical practice despite guideline recommendations," said Pak Kin Wong, professor of biomedical engineering and mechanical engineering and principal investigator on the study. The research was published today (May 22) in Science Advances.

Wong said that expensive special equipment is required to detect urinary solutes and minerals for a test result. The urine sample, therefore, has to be shipped to a commercial diagnostic lab for testing. To solve this, the research team developed a biomimetic detection system called slippery liquid-infused porous surface (SLIPS)-LAB.

SLIPS is a dynamic, extremely low-friction smooth surface created by locking lubricating liquids in micro/nanostructured substrates. This is inspired by nepenthes pitcher plants, which are carnivorous plants that have unique leaves shaped like pitchers and are filled with digestive liquid. The plants have evolved extremely slippery liquid-infused micro-textured rims that cause insects to fall into the "pitcher."

"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," Wong said.

The test results can then be read using a scanner or a cell phone, and the scanned image can then be analyzed using a computer algorithm. All these steps, according to Wong, would take approximately 30 minutes in a physician's office. An added benefit, Wong said, is that SLIPS-LAB is more cost-effective than regular, 24-hour testing.

 

Access the article.