A new smartphone application from the University of Cambridge may make monitoring conditions like kidney disease, diabetes, or urinary tract infections easier for patients and doctors. Eventually it could be used to slow or limit the spread of pandemics in developing countries.
The app, named Colorimetrix, accurately measures color-based, or colorimetric, tests for use in home, clinical or remote settings, and allows for transmission of medical data directly from patients to health professionals.
Healthcare decentralization and disintermediation via inexpensive and very portable point of care diagnostics opens up the possibility to revolutionize today’s limitations in patient screening.
But diagnosis can be stymied by poor infrastructure and skilled healthcare worker shortages, especially in the developing world. Defeating such hindrances through more accessible diagnostics could reduce the burden on health care workers.
Colorimetric Widely Used Test
Colorimetric tests, because of their portability and ease of use, are widely used for environmental analysis, drug testing and medical monitoring, in a range of different settings throughout the world.
These tests, usually in the form of small strips, work by producing color change in a solution: the intensity of the color which is produced determines the concentration of that solution. One example many are familiar with is the test for measuring pH levels.
One downside is that these tests can be difficult to read accurately, particularly when used in a home or remote setting however. False positive readings are incredibly common. Erroneous diagnosis or treatment can take place as a result.
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.
The Colorimetrix app makes precise reading of colorimetric tests much easier. It uses only a mobile phone’s camera along with a special algorithm for conversion of data from colorimetric tests into a numerical concentration value on the phone’s screen, all within a few seconds.
After testing urine, saliva or other bodily fluid with a colorimetric test, you just snap a picture of the test with your phone’s camera.
The app analyses the colors of the test, then compares them with a pre-recorded calibration, and shows the numerical result on the phone’s screen. The result can then be stored, sent to a healthcare professional, or directly analyzed by the phone for diagnosis.
The Colorimetrix app is available for both Android and iOS mobile devices. It can be used in home, clinical, or resource-limited settings. It has been shown to accurately report glucose, protein and pH concentrations from commercially-available urine test strips without requiring any external hardware, the first time that a mobile phone app has been used in this way in a laboratory setting.
“This app can substitute for laboratory equipment, saving money to clinics and research institutions,” said app developer Dr Leo Martinez.
A beta version of the app can be requested for research purposes by sending an email to firstname.lastname@example.org with the following information:
-Email and Phone
Ali K. Yetisen, J.L. Martinez-Hurtado, Angel Garcia-Melendrez, Fernando da Cruz Vasconcellos, Christopher R. Lowe.
A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests.
Sensors and Actuators B: Chemical, 2014; 196: 156 DOI: 10.1016/j.snb.2014.01.077
Image Credit: Ali Yetisen