(27au) A Point-of-Care Device Capable of High-Throughput Diagnostic Testing Using Recombinase Polymerase Amplification (RPA)

The Point-of-Care Incubator for Isothermal Nucleic Acid Amplification Tests, or the “PIINT,” is a device that aims to meet the standards set by the World Health Organization (WHO) for point-of-care (POC) testing; these requirements include being equipment-free, user-friendly, robust, and affordable. This presentation will focus on the development of the PIINT for RPA-based diagnostics and its potential for POC applications. The design of the PIINT regulates reaction temperatures during testing and minimizes temperature fluctuations in a manner that eliminates the need for control circuitry.

The WHO has found that three of the top ten causes of death involve infectious diseases. Testing availability is a significant impediment in low-resource settings where the risk of death from infectious disease is highest. POC tests, which provide on-site rather than clinical results, are vital for improving global health. The WHO has created a list of criteria for evaluating POC devices, the “ASSURED” standards: Affordable, Sensitive, Specific, User-Friendly, Rapid and Robust, Equipment-free, and Deliverable. For infectious diseases, the nucleic acid amplification test (NAAT) polymerase chain reaction (PCR) is the gold standard for diagnosis. However, PCR requires intensive thermocycling performed by trained professionals. Recombinase polymerase amplification (RPA) is a NAAT that shows greater promise for POC testing. RPA operates at a temperature range of 37-42°C. In this work, we have addressed the principal issues of temperature stability during incubation. The PIINT can incubate samples in the target temperature range for much longer than the RPA reaction time required. Additionally, during a 12-hour testing scenario, the PIINT, which holds three samples at a time, was used to incubate 60 mock reactions in 20 consecutive rounds. Because of the PIINT’s ability to mediate temperature fluctuations, the device could be opened to remove and replace samples, making successive incubations possible. This demonstrates the ability of the PIINT to run tests in a POC setting with high throughput and little energy use without the need for laboratory equipment.