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Abstract Novel methods that enable sensitive, accurate and rapid detection of RNA would not only benefit fundamental biological studies but also serve as diagnostic tools for various pathological conditions, including bacterial and viral infections and cancer. Although highly sensitive, existing methods for RNA detection involve long turn‐around time and extensive capital equipment. Here, an ultrasensitive and amplification‐free RNA quantification method is demonstrated by integrating CRISPR‐Cas13a system with an ultrabright fluorescent nanolabel, plasmonic fluor. This plasmonically enhanced CRISPR‐powered assay exhibits nearly 1000‐fold lower limit‐of‐detection compared to conventional assay relying on enzymatic reporters. Using a xenograft tumor mouse model, it is demonstrated that this novel bioassay can be used for ultrasensitive and quantitative monitoring of cancer biomarker (lncRNA H19). The novel biodetection approach described here provides a rapid, ultrasensitive, and amplification‐free strategy that can be broadly employed for detection of various RNA biomarkers, even in resource‐limited settings.
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CRISPR-based strategies for sample-to-answer monkeypox detection: current status and emerging opportunities
Abstract The global health threat posed by the Monkeypox virus (Mpox) requires swift, simple, and accurate detection methods for effective management, emphasizing the growing necessity for decentralized point-of-care (POC) diagnostic solutions. The clustered regularly interspaced short palindromic repeats (CRISPR), initially known for its effective nucleic acid detection abilities, presents itself as an attractive diagnostic strategy. CRISPR offers exceptional sensitivity, single-base specificity, and programmability. Here, we reviewed the latest developments in CRISPR-based POC devices and testing strategies for Mpox detection. We explored the crucial role of genetic sequencing in designing crRNA for CRISPR reaction and understanding Mpox transmission and mutations. Additionally, we showed the integration of CRISPR-Cas12 strategy with pre-amplification and amplification-free methods. Our study also focused on the significant role of Cas12 proteins and the effectiveness of Cas12 coupled with recombinase polymerase amplification (RPA) for Mpox detection. We envision the future prospects and challenges, positioning CRISPR-Cas12-based POC devices as a frontrunner in the next generation of molecular biosensing technologies.
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- PAR ID:
- 10553517
- Publisher / Repository:
- IOP Publishing
- Date Published:
- Journal Name:
- Nanotechnology
- Volume:
- 36
- Issue:
- 4
- ISSN:
- 0957-4484
- Format(s):
- Medium: X Size: Article No. 042001
- Size(s):
- Article No. 042001
- Sponsoring Org:
- National Science Foundation
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