This is a companion article to the feature, “Point-of-Care Testing Continues Growth.”
Dev Chatterjee, PhD, cofounder of BreviTest Technologies LLC, Houston, takes a novel approach to point-of-care diagnostics that reimagines the immunoassay method as serial reactions in connected microfluidic chambers, eliminating the traditional requirement of multiple washes to comprehensively remove residual reactants. BreviTest’s patent-pending technology has been reduced to practice with a prototype that has successfully demonstrated completely automated enzyme-linked immunosorbent assay (ELISA) reactions.
Unlike testing in clinical laboratories, which can take several hours and requires expensive equipment and experienced technicians, BreviTest’s technology can perform tests at the point of care in 5 to 10 minutes. Using customizable disposable cartridges and established chemistries, the technology could be used to perform a broad range of tests in doctor’s offices and emergency settings, as well as in non-emergency settings such as in home monitoring for chronic diseases and allergen detection.
“We are in the development phase. We have to complete the extensive validation required to commercialize a device, and expect to be on the market in the next 12 months,” says Chatterjee. “With that caveat, it is an exciting development and has the potential to revolutionize the way we do some clinical tests.”
“In the clinical laboratory, the gold standard among immunoassay methods is ELISA. But performing ELISAs requires technical expertise, a well-equipped laboratory, and several hours,” says Chatterjee. “At the point of care, lateral-flow immunoassays are used, but they generally have lower sensitivities than ELISAs and are not useful where quantitation is required.”
BreviTest’s novel technology allows the user to perform actual ELISAs at the point of care. The technology uses enzyme-enhanced signal amplification, and each test uses exactly the same chemicals in about the same volumes as used in a laboratory immunoassay. “As a result, we do not need to develop new assays—we can just take any established ELISA and transfer it directly to our device platform,” says Chatterjee.
In the BreviTest device, the ELISA reaction takes place in a polymer cartridge that can be disposed after use. The total time to run an ELISA is under 10 minutes.
“We translated the technology into a portable device, the Acuity analyzer, which runs on rechargeable batteries,” says Chatterjee. We have made the operation extremely simple, with the user required only to load a small amount of sample (about 20 microliters) into the cartridge, load it into the device, and close it. The test is run through a smartphone or tablet interface.”
Using the Acuity device, preliminary proof of concept was obtained using a commercially available ELISA. And the company has also demonstrated the ability to perform ELISA serology on human serum for diseases like ebola.
Chatterjee believes that the Acuity device could emerge as the platform that helps uninstrumented and instrumented POC devices converge, by combining the current advantages of each class. “But many more tests will need to be done before we can start commercializing the device,” he says. “In the meantime, several companies have expressed interest in working with us.”