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Current in vitro diagnostic tests, used to detect or monitor conditions such as an infectious disease or diabetes, typically involve either manual lab-based testing or use of a disposable test cartridge with a customised reader.
Andrew Chapman wants to reduce the cost and complexity of such testing by eliminating the need for diagnostic companies to develop expensive reading equipment. He hopes to achieve this with inVi, his concept for an in vitro diagnostic test cartridge that exploits multiple embedded sensing technologies that exist in all smartphones.
Chapman says: “With inVi, companies would be able to develop a new generation of diagnostic tests that are specifically designed to work with a smartphone, and without needing to invest time and resource in developing dedicated reading equipment.”
The inVi architecture is similar to existing systems where a diagnostic test cartridge contains all the necessary reagents alongside elements that can be activated by and/or interact with the reading instrument (for example plungers that act on physical elements within the cartridge). But with inVi it is the user who provides the actuation and their smartphone both instructs and verifies the steps as they happen.
The user simply adds a sample, such as saliva, urine or blood, and positions the transparent cartridge on the touchscreen – the app checks the cartridge is in the correct position and then starts the test.
The app then prompts the user to carry out specific actions, illuminating different regions of the screen as required, and provides visual, audible or vibration feedback to confirm the successful completion of each step. At the end of the test the app displays the test results.
“For example, the resonant mixer and valves would work with the smartphone’s in-built vibration motor to combine samples with appropriate reagents,” explains Chapman. “An ‘intelligent element’ within the cartridge could measure an electrochemical change and transmit that wirelessly to the device using Bluetooth Low Energy; or the smartphone camera could be used to detect a specific colour change within a chamber in the cartridge.”
Securing the test data will be key. “It’s early days but the team at 42 Technology recognises that data security and ‘backend’ data management are essential areas that will need to be thought through before implementation,” says Chapman.
He hopes that inVI will make testing quicker, easier and more convenient. It could also mean that medical issues could be detected earlier because a wider range of tests could be performed at home, in GP surgeries or in remote locations where healthcare resources are scarce.
Chapman’s inVi will initially be focused on providing patients with an indication that they need a more thorough examination in a healthcare environment where the doctor can look at the test result, diagnose and advise on or prescribe the necessary treatment. He adds: “The inVi could also be invaluable for epidemic tracking where the tests could be of a lower fidelity but still prove useful. Especially if they were correlated with, for example, location data from the smartphone.”
The concept is still in its early stages. Chapman and the team at 42 Technology will need to collaborate with one or more development partners to design key elements, engineer the physical interaction of the cartridge with the touchscreen, and integrate all of the required functionality into a low-cost plastic cartridge.
The inVi concept was well received when it was shown to industry experts for the first time at a medical technology exhibition earlier this year. Staff at 42 Technology are now looking for partners to help develop the core technology, and to bring the inVi to market.