CPA-Cas12a-based lateral flow strip for portable assay of Methicillin-resistant Staphylococcus aureus in clinical sample

Advancements of CRISPR technology in public health-related analysis

Pathogens and contaminants in food and the environment present significant challenges to human health, necessitating highly sensitive and specific diagnostic methods. Traditional approaches often struggle to meet these requirements. However, the emergence of the Clustered Regularly Interspaced Short Palindromic Repeats (CRISPR) system has revolutionized nucleic acid diagnostics. The present review provides a comprehensive overview of the biological sensing technology based on the CRISPR/Cas system and its potential applications in public health-related analysis. Additionally, it explores the enzymatic cleavage capabilities mediated by Cas proteins, highlighting the promising prospects of CRISPR technology in addressing bioanalysis challenges. We discuss commonly used CRISPR-Cas proteins and elaborate on their application in detecting foodborne bacteria, viruses, toxins, other chemical pollution, and drug-resistant bacteria. Furthermore, we highlight the advantages of CRISPR-based sensors in the field of public health-related analysis and propose that integrating CRISPR-Cas biosensing technology with other technologies could facilitate the development of more diverse detection platforms, thereby indicating promising prospects in this field.

Efficient magnetic enrichment cascade single-step RPA-CRISPR/Cas12a assay for rapid and ultrasensitive detection of Staphylococcus aureus in food samples

Staphylococcus aureus (S. aureus) is a prevalent foodborne pathogen that could cause severe food poisoning. Thus, rapid, efficient, and ultrasensitive detection of S. aureus in food samples is urgently needed. Here, we report an efficient magnetic enrichment cascade single-step recombinase polymerase amplification (RPA)-CRISPR/Cas12a assay for the ultrasensitive detection of S. aureus. Magnetic beads (MBs) functionalized with S. aureus-specific antibodies were initially used for S. aureus enrichment from the complex matrix, with 98% capture efficiency in 5 min and 100-fold sensitivity improvement compared with unenriched S. aureus. Next, a single-step RPA-CRISPR/Cas12a-based diagnostic system with optimized extraction-free bacteria lysis was constructed. This assay could detect as low as 1 copy/μL (five copies/reaction) of extracted DNA template and 10 CFU/mL of S. aureus within 40 min. Furthermore, the assay could effectively detect S. aureus in real food samples such as lake water, orange juice, pork, and lettuce, with concordant results to qPCR assays. The proposed cascade signal-amplification assay eliminates the need for lengthy bacterial culture and complex sample preparation steps. Hence, the proposed assay shows great application potential for rapid, efficient, and ultrasensitive detection of pathogens in real food samples.

Microfluidic-assisted integrated nucleic acid test strips for POCT

Numerous diseases have posed significant threats to public health, notably the global pandemic of COVID-19, resulting in widespread devastation due to its high infectivity and severity. The nucleic acid lateral flow assay (NALFA) addresses challenges of complexity, cost, and time associated with traditional assays, offering a reliable platform for rapid and precise nucleic acid target detection. NALFA is gaining prominence as a point-of-care testing (POCT) technique, thanks to its user-friendly operation and rapid results. Nevertheless, conventional NALFA relies on specialized technicians and involves labor-intensive steps like DNA extraction and PCR processes, impeding its efficiency. To overcome these limitations, integrating NALFA with microfluidic technology, widely employed in rapid field detection, holds promise. This review comprehensively outlines prevailing strategies for integrating NALFA, encompassing both research initiatives and commercial applications. Addressing the bottleneck of nucleic acid amplification as a rate-limiting step, the review delves into progress in amplification-free NALFA and highlights prevalent signal amplification techniques. Ultimately, the review outlines the future prospect of integrated NALFA development, capturing the technology's evolution and providing valuable insights for academic and commercial endeavors.