Colorimetrix, a new app developed by University of Cambridge researchers, turns a smartphone into a portable medical diagnostic device.

The app could make monitoring conditions such as HIV, tuberculosis, malaria, diabetes, kidney disease, and urinary tract infections clearer and easier for both patients and doctors, and could eventually be used to slow or limit the spread of pandemics in the developing world, the researchers say.

The app accurately performs colorimetric (color-based) tests for use in home, clinical, or remote settings, and enables transmission of medical data from patients directly to health professionals.

Colorimetric tests are widely used for medical monitoring, drug testing and environmental analysis because of their portability, compact size, and ease of use. The tests, typically in the form of small strips, work by producing color change in a solution: the intensity of the color produced determines the concentration of that solution.

But when used in a home or remote setting, these tests can be difficult to read accurately. False readings are very common, which can result in erroneous diagnosis or treatment. Specialized laboratory equipment such as spectrophotometers or test-specific readers can be used to automate the readouts with high sensitivity, but these are costly and bulky.

How it works

1. After testing urine, saliva or other bodily fluid with a colorimetric test, take a photo of the test strip with the phone’s camera.

2. The app analyzes the colors of the test, compares them with pre-recorded calibration data, and displays a numerical result on the phone’s screen. It app has shown accurately report glucose, protein, and pH concentrations from commercially available urine test strips, for example.

3. Send the result to a healthcare professional for a diagnosis.

By enabling transmission of medical data to health professionals in real time, the app could also be a valuable public health tool.

The app is currently available in an Android version at www.colorimetrix.com for researchers and developers. An iOS version is in the works.

The team is also planning to use the app for clinical testing of kidney function and infections at Addenbrooke’s Hospital.

Details were recently published in the journal Sensors and Actuators B: Chemical.

“This app has the potential to help in the fight against HIV, tuberculosis and malaria in the developing world, bringing the concept of mobile healthcare to reality,” said Ali Yetisen, a PhD student in the Department of Chemical Engineering & Biotechnology, who led the research. “By quickly getting medical data from the field to doctors or centralized laboratories, it may help slow or limit the spread of pandemics.”

“Decentralization of healthcare through low-cost and highly portable point-of-care diagnostics has the potential to revolutionize current limitations in patient screening. However, diagnosis can be hindered by inadequate infrastructure and shortages in skilled healthcare workers, particularly in the developing world.”

Yetisen told KurzweilAI that the team seeks to establish partnerships with service providers and others to allow this technology to get to home users — especially patients with diabetes for monitoring their blood sugar levels from home. He said the team plans to release the app publicly by the end of Summer 2014.

Abstract of Sensors and Actuators B: Chemical paper

A smartphone application algorithm with inter-phone repeatability was developed for both Android and iOS operating systems. The app transformed the smartphone into a reader to quantify commercial colorimetric urine tests with high accuracy and reproducibility in measuring pH, protein, and glucose. The results showed linear responses in the ranges of 5.0–9.0, 0–100 mg/dL and 0–300 mg/dL, respectively.