Project Lead(s): David Juncker
Issue
Rapid Diagnostic Tests (RDTs) have become widely used in low-resource settings for many diseases and have had a major impact in targeting therapies to people who need it.
However, the accuracy of these tests remains a matter of concern and there is a need for better RDTs for diseases such as leishmaniasis.
Solution
The project goal was to develop a thread-based (yarn) RDT for leishmaniasis detection.
A thread-based electrochemical biosensor was developed as an alternative to colorimetric assays on thread and this was coupled with development of a smartphone diagnostic application, to produce a semi-quantitative readout and reduce the subjectivity of the readout.
The electrochemical signal was amplified using an enzymatic reaction to improve the sensitivity of the assay.
In addition, the setup was on a rotating disk to facilitate reagent delivery without the need for pipettes.
A preliminary sandwich immunoassay was designed to test the device.
Outcome
The project team was able to optimize the different components that are necessary to develop a working prototype of a yarn-based rapid test for leishmaniasis.
The smartphone app demonstrated that it was possible to quantify the concentration on analyte but, to date, this only works in controlled situations, as light, angle and background fluctuations significantly affected the results.
The application needs to be further developed to account for variations, both with software and with hardware, to make the analysis more robust.
Knowledge of the project was disseminated at conferences.