Detecting HIV in Whole Blood using an Integrated Paper-based Consumable that Enables Direct Amplification of Purified RNA from Paper

Abstract

A definitive diagnosis of HIV typically requires a positive nucleic acid test. Limited access to these tests means that initiation of anti-HIV therapy is delayed or does not occur in a significant part of the world. While rapid antigen tests are more broadly available, these are insufficient for diagnosis on their own. To address the challenge of improving access to HIV testing, we have developed a passive, paper-based microfluidic sample preparation device we term the QuickDraw. We demonstrate that QuickDraw efficiently processes HIV-containing finger stickquantities of whole blood to yield purified viral RNA. The output of the QuickDraw is then used as input for a colorimetric reverse transcriptase -loop-mediated isothermal amplification (RT-LAMP) assay. Coupled with sample preparation conducted with the QuickDraw, the assay demonstrated a limit of detection of 1,000 copies/mL, with a PPV of 93% and an NPV of 87%. QuickDraw simplifies viral nucleic acid sample preparation and detection by dramatically reducing the amount of equipment needed, suggesting it could be suitable for deployment in clinical and low-resource settings. By decentralizing nucleic acid testing, the QuickDraw platform has the potential to expand access to nucleic acid diagnostics in low-middle income countries (LMICs), while also supporting the UNAIDS goals for HIV detection, leading to wider access to treatment and reduced community transmission. It is also a significant step towards the goal of a simple-to-use nucleic acid-based HIV self test.