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Nucleic acid tests are key tools for the detection and diagnosis of many diseases. In many cases, the amplification of the nucleic acids is required to reach a detectable level. To make nucleic acid amplification tests more accessible to a point-of-care (POC) setting, isothermal amplification can be performed with a simple heating source. Although these tests are being performed in bulk reactions, the quantification is not as accurate as it would be with digital amplification. Here, we introduce the use of the vibrating sharp-tip capillary for a simple and portable system for tunable on-demand droplet generation. Because of the large range of droplet sizes possible and the tunability of the vibrating sharp-tip capillary, a high dynamic range (~2 to 6000 copies/µL) digital droplet loop-mediated isothermal amplification (ddLAMP) system has been developed. It was also noted that by changing the type of capillary on the vibrating sharp-tip capillary, the same mechanism can be used for simple and portable DNA fragmentation. With the incorporation of these elements, the present work paves the way for achieving digital nucleic acid tests in a POC setting with limited resources.
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Rapid Amplification and Detection of Single‐Stranded Nucleic Acids for Point‐of‐Care Diagnosis
Abstract Nucleic acid detection plays a crucial role in various applications, including disease diagnostics, research development, food safety, and environmental health monitoring. A rapid, point‐of‐care (POC) nucleic acid test can greatly benefit healthcare system by providing timely diagnosis for effective treatment and patient management, as well as supporting diseases surveillance for emerging pandemic diseases. Recent advancements in nucleic acids technology have led to rapid assays for single‐stranded nucleic acids that can be integrated into simple and miniaturized platforms for ease of use. In this review, the study focuses on the developments in isothermal amplification, nucleic acid hybridization circuits, various enzyme‐based signal reporting mechanisms, and detection platforms that show promise for POC testing. The study also evaluates critical technical breakthroughs to identify the advantages and disadvantages of these methods in various applications.
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- Award ID(s):
- 2141141
- PAR ID:
- 10610831
- Publisher / Repository:
- Wiley Blackwell (John Wiley & Sons)
- Date Published:
- Journal Name:
- Small Methods
- Volume:
- 9
- Issue:
- 6
- ISSN:
- 2366-9608
- Format(s):
- Medium: X
- Sponsoring Org:
- National Science Foundation
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