image: An HIV detection platform combining paper-based sample preparation with real-time isothermal amplification. (left) The handheld device is composed of three main components: a buffer unit at the top, a mixing unit in the middle, and a detection unit at the bottom. The buffer unit contains four reservoirs for housing lysis buffer, binding buffer, and 2 wash buffers, and the sequential release of these buffers are controlled by ball-based valves. The buffer unit and mixing unit can slide with each other, and the mixing unit is integrated with the detection unit through a protrusion beneath the mixing unit. Each valve closes with a bearing ball acting as a plug for the reservoir. As the buffer unit slides along the mixing unit, the valve is activated by a pin in the mixing unit, which pushes the ball up to release the liquid from the reservoir when the pin is aligned with the ball. The detection unit contains a paper pad, which enriches viral RNA as illustrated in the image above the arrow. . (middle) Image of a fully assembled, real-time detector consisting of a handheld microscope mounted on a 3D-printed stand, which houses three compartments at its base for a heater, batteries, and an integrated electrical circuit for controlling temperature. (right) A computer screen with (1) an image of two wells in the detection unit: one well for a sample that had a positive signal while the other well is for the negative control which is dark; and (2) amplification curves from the real-time detector. The computer can be replaced by a smart phone with an App, as demonstrated in this work.
Credit: Microsystems & Nanoengineering
A team of researchers from the University of Florida has developed an innovative handheld device for human immunodeficiency virus (HIV) detection that combines paper-based sample preparation with real-time isothermal amplification. This low-cost, portable platform promises rapid and accurate HIV diagnosis at the point of care (POC), overcoming the limitations of traditional laboratory-based tests. By eliminating the need for complex equipment and specialized personnel, this device is poised to revolutionize early HIV detection and management, particularly in resource-limited settings. With results delivered in as little as 60 minutes, the device offers unprecedented speed and reliability, matching the sensitivity of standard laboratory assays.
Human immunodeficiency virus (HIV) remains a global health challenge, with millions of people affected worldwide. Early diagnosis is essential for timely antiretroviral therapy and preventing transmission. However, current nucleic acid tests (NATs) often require advanced laboratory infrastructure and trained personnel, making them impractical in low-resource settings. While antibody-based rapid tests provide convenience, they lack sensitivity during the acute phase of infection and fail to distinguish between acute and chronic stages. These limitations highlight the urgent need for affordable, sensitive, and portable HIV detection tools that can be easily deployed at the point of care (POC).
On September 6, 2024, a team from the University of Florida unveiled their handheld HIV detection platform, published (DOI: 10.1038/s41378-024-00822-1) in Microsystems & Nanoengineering. This device integrates paper-based sample preparation with real-time reverse transcription loop-mediated isothermal amplification (RT-LAMP), offering an affordable and efficient alternative for HIV testing. The device stands as a breakthrough in POC diagnostics, combining simplicity, portability, and high sensitivity to create a solution that could transform global HIV testing.
The new HIV detection platform offers a novel integration of paper-based sample preparation and isothermal amplification, eliminating the need for lab equipment like centrifuges or pipettes. Viral RNA is extracted from samples onto a paper substrate, and subsequently amplified via RT-LAMP in a compact, battery-powered heating unit. Detection is achieved through colorimetric indicators or real-time imaging. The device demonstrated a detection limit of 30 copies/mL of HIV RNA, a level comparable to traditional laboratory methods, with no cross-reactivity to hepatitis C virus (HCV). Clinical testing confirmed 100% specificity, ensuring the device's accuracy for HIV diagnosis. Moreover, the real-time detection capability allows for quantitative viral load measurement, which is critical for assessing treatment efficacy and drug resistance. By delivering results in under 60 minutes, the device significantly reduces the time required compared to traditional PCR-based methods, providing a rapid diagnostic solution in resource-poor environments.
Dr. Z. Hugh Fan, a key researcher on the project, emphasized the transformative potential of this technology: "Our handheld device addresses the critical need for rapid, accurate, and accessible HIV testing. By integrating sample preparation and real-time detection in a portable format, we have created a tool that can change the landscape of HIV diagnosis, particularly in resource-limited areas where laboratory infrastructure is scarce."
This handheld HIV detection platform can have wide-reaching implications for global health. Its low cost, portability, and high sensitivity make it an ideal tool for POC testing in low-resource environments, where access to traditional diagnostic methods is limited. In addition to improving HIV management and treatment outcomes, the technology’s adaptability opens the door for detecting other pathogens, expanding its potential to revolutionize infectious disease diagnostics worldwide.
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References
DOI
Original Source URL
https://doi.org/10.1038/s41378-024-00822-1
Funding information
This work was supported in part by the University of Florida, USA (DRPD-ROF2020), the US National Institutes of Health (R01AI155735, R61AI181016, and R42AI122855), and the Gatorade Trust through funds distributed by the University of Florida, Department of Medicine.
About Microsystems & Nanoengineering
Microsystems & Nanoengineering is an online-only, open access international journal devoted to publishing original research results and reviews on all aspects of Micro and Nano Electro Mechanical Systems from fundamental to applied research. The journal is published by Springer Nature in partnership with the Aerospace Information Research Institute, Chinese Academy of Sciences, supported by the State Key Laboratory of Transducer Technology.
Journal
Microsystems & Nanoengineering
Subject of Research
Not applicable
Article Title
A handheld HIV detection platform using paper-based sample preparation and real-time isothermal amplification
Article Publication Date
6-Sep-2024
COI Statement
The authors declare that they have no competing interests.