Colorimetric test strips can help diagnose a lot of diseases and are also used in monitoring disease progression. They are cheap and easy to use, but the hard part is interpreting the colored lines that appear. There are currently projects underway to make this step nearly automatic, but a team at University of Cambridge have already developed an app that reads colorimetric test strips, works on a variety of smartphones, and allows easy sharing of readings with remote healthcare providers.
The Colorimetrix test analyser app uses the smartphone’s camera to detect the color and location of lines on test strips. If that sounds simple, the Cambridge team describes it with much more gusto: “The smartphone app measures electromagnetic radiation from the coloured test zones with the complementary metal-oxide-semiconductor (CMOS) sensor present in the smartphone camera.” The app was successfully tested using test strips currently used in clinical practice using both iPhones and Android powered devices. The study results showed that the app provides a linear response when measuring glucose, protein, and pH.
Benefits of the app according to its info page:
- Comparable in accuracy to commercial colorimetric readers.
- Equipment-free design: no spectrophotometer, computer or customized software needed.
- Colorimetric test results available within seconds.
- Full, easy and secure personal access to test results on smartphone. Immediate access to the ‘cloud’ using the phone’s connectivity.
- Costs an order of magnitude lower than comparable colorimetric test readers.
- One reader for many strips, tests, assays, microplates, or solutions.
- Easy use for transport to remote field locations.
- No external power supply required, works with low- and high-end smartphones.
- No network access required for analysing and storing results.
- Possibililty of customising for secure transmission and storage of test data.
Study in journal Sensors and Actuators B: Chemical: A smartphone algorithm with inter-phone repeatability for the analysis of colorimetric tests…
Cambridge: Pocket diagnosis…