Abstract
A visual DNA diagnosis with a rapid and simple procedure has been developed on integrating recombinase polymerase amplification (RPA) and a gold nanoparticle (AuNP) probe. The entire process is implemented in only one tube with no precision instrument and requires in total 20 min to amplify a DNA fragment with RPA and to discriminate a DNA fragment with an AuNP probe. The result in various colors is directly observable with the naked eye. Through discovering a small DNA fragment of Tomato yellow leaf curl virus (TYLCV), this system can detect one copy per microlitre of virus in a pure isolate of extracted DNA and can readily identify an infected plant with a healthy appearance. This system hence provides a highly sensitive and stable DNA diagnosis. This visual method has a potential for disease diagnosis and prognostication in the field based on advantages of simplicity, high speed, portability and sensitivity.
Highlights
Visual observations of disease symptoms in plant tissues contribute towards the diagnosis of disease, but this approach typically requires an experienced pathologist and is unreliable when symptoms appear at an early stage of infection
A novel approach can enhance the reliability of colorimetric detection of AuNP aggregation in qualitative and quantitative analysis with the naked eye[27], which can facilitate an expansion of the applications of a AuNP probe in DNA detection
Apart from a total DNA extraction, two main steps were conducted in three stages in visual DNA diagnosis, including Recombinase polymerase amplification (RPA), hybridization of AuNP probe and visual detection
Summary
Visual observations of disease symptoms in plant tissues contribute towards the diagnosis of disease, but this approach typically requires an experienced pathologist and is unreliable when symptoms appear at an early stage of infection. Nucleic-acid-based methods have greater accuracy, specificity and sensitivity than methods based on immunology, but they rely strongly on expertise and instruments in the laboratory, which becomes a limitation for their portable application in the field[6,7]. The reaction is complete in 20–40 min but the duration of detection limit is as little as 5 min Among those approaches, RPA has the advantages of being simple and convenient to perform at a low temperature and for a short period while still possessing the characteristics of exponential amplification efficiency and highly sensitive detection[12]. The performance of our approach is compared directly with conventional bench-top methods This rapid and simple system can be employed in qualitative and quantitative analysis of pathogens and broad applications in disease diagnosis and prognostication
Sign-in/Register to view highlights & summary Talk to us
Join us for a 30 min session where you can share your feedback and ask us any queries you have
Schedule a callDisclaimer: All third-party content on this website/platform is and will remain the property of their respective owners and is provided on "as is" basis without any warranties, express or implied. Use of third-party content does not indicate any affiliation, sponsorship with or endorsement by them. Any references to third-party content is to identify the corresponding services and shall be considered fair use under The CopyrightLaw.
