Smartphone-based device boosts kidney damage assessment process

Researchers at UCLA and the California NanoSystems Institute have developed a smartphone device that accurately determines albumin (a protein) in urine, according to an article in the peer-reviewed journal Lab on a Chip.

"Albumin testing is frequently done to assess kidney damage, especially for diabetes patients," said Aydogan Ozcan, a professor of electrical engineering and bioengineering at the UCLA Henry Samueli School of Engineering and Applied Science, and associate director of the California NanoSystems Institute, in a written statement. "This device provides an extremely convenient platform for chronic patients at home or in remote locations where cell phones work."

Detection of albumin is important because if kidney damage has occurred the protein will leak into a person's bloodstream and will be present in the urine. A patient can take a urine sample and the smartphone attachment images and "automatically analyzes fluorescent assays confined within disposable test tubes for sensitive and specific detection of albumin in urine."

Weighing about one third of a pound, the Albumin Tester is installed on a smartphone's camera, where test and control tubes are inserted from the side and are excited by a battery-powered laser diode. An Android app processes the raw images in less than one second and the device transmits the test results to a database or healthcare provider.

"Using a simple sample preparation approach which takes [about 5 minutes] per test (including the incubation time), we experimentally confirmed the detection limit of our sensing platform as [less than 10 micrograms per milliliter], which is more than 3 times lower than the clinically accepted normal range, in buffer as well as urine samples," study authors write. "This automated albumin testing tool running on a smartphone could be useful for early diagnosis of kidney disease or for monitoring of chronic patients, especially those suffering from diabetes, hypertension, and/or cardiovascular diseases."

Ozcan estimates that the device--for which his lab also has developed an iPhone app--could be produced commercially for $50 to $100 per unit.

In related news, an Indian startup has developed an iPhone app that allows people to conduct their own urine analysis at home or on the go using conventional dipsticks in order to better manage diseases like diabetes, urinary tract infections and pre-eclampsia. Called uChek, the app analyzes urine for the presence of up to 10 biomarkers including glucose, protein, ketones, blood, pH, specific gravity, urobilinogen, bilirubin, leukocytes and nitrites. 

uChek uses a smartphone's camera to take photos of chemical strips that are dipped in a urine sample. The app then compares them to a color-coded map and within a few seconds reports the results. 

To learn more:
- read the article
- read the annoucement