Multiplexed Detection Strategies for Biosensors Based on the CRISPR-Cas System

CRISPR/Cas bioimaging: From whole body biodistribution to single-cell dynamics

This review explores the transformative role of CRISPR/Cas systems in optical bioimaging, emphasizing how advancements in nanoparticle (NP) technologies are revolutionizing the visualization of gene-editing processes both in vitro and in vivo. Optical imaging techniques, such as near-infrared (NIR) and fluorescence imaging, have greatly benefited from the integration of nanoformulated contrast agents, improving resolution, sensitivity, and specificity. CRISPR/Cas systems, originally developed just for gene editing, are now being coupled with these imaging modalities to enable real-time monitoring and quantitative measurements of metabolites, vitamins, proteins, nucleic acids and other entities in specific areas of the body, as well as tracking of CRISPR/Cas delivery, editing efficiency, and potential off-target effects. The development of CRISPR/Cas-loaded NPs allows for enhanced imaging and precise monitoring across multiple scales with multiplexed and multicolor imaging in complex settings, including potential in vivo diagnostics. CRISPR/Cas therapeutics as well as diagnostics are hindered by the lack of efficient and targeted delivery tools. Biomimetic NPs have emerged as promising tools for improving biocompatibility, enhancing targeting capabilities, and overcoming biological barriers, facilitating more efficient delivery and bioimaging of CRISPR/Cas systems in vivo. As the design of these NPs and delivery mechanisms improves, alongside advancements in endolysosomal escape, CRISPR/Cas-based bioimaging will continue to advance, offering unprecedented possibilities in precision medicine and theranostic applications.

Micro-scale thermofluidics enable autonomous and scalable CRISPR diagnostics for sexually transmitted infections screening

The development of clustered regularly interspaced short palindromic repeats (CRISPR)-based nucleic acid detection has recently been a center of interest for next-generation molecular diagnostics. Despite considerable advances, simple and effective strategies to harness the isothermal amplification reaction and CRISPR-based detection for maximal performance and minimal complexity are still desirable. Here, a thermofluidic approach leverages the micro-scale chemical and physical mechanism to perform autonomous and scalable CRISPR-based diagnostics (CRISPR-Dx) in a greatly simplified format, which was called "Thermofluidic CRISPR". Originating from the concept of convective PCR, it utilizes looped microchannel reactors to perform approximatively undisturbed isothermal amplification reaction at balanced temperature by virtue of the restricted molecular diffusion across the microchannel, in which the reagents of two reactions are compartmentalized virtually; then it creates circulatory flow within the loop channel to mix the amplificons and CRISPR reagents via Rayleigh-Bénard thermal convection, by simply warming up one side of the loop channel. Due to the simplicity and scalability, a low-cost, battery-powered, portable diagnostic platform, incorporating with smartphone-enabled real-time fluorescence readout, to perform rapid (<30 min), highly sensitive (2 copies per reaction), quantitative and multiplexed CRISPR-Dx was constructed. Its diagnostic performance in rapid screening of multiple pathogens from 196 clinical samples for syndromic testing of sexually transmitted infections was evaluated, exhibiting 97.4 % sensitivity and 100 % specificity benchmarked against the laboratory-based testing. Leveraging the micro-scale chemical and physical mechanism to simplify workflows for CRISPR-Dx may enhance their versatility and facilitate their broader applicability at the point of care.

CRISPR integrated biosensors: A new paradigm for cancer detection

Cancer remains one of the leading causes of morbidity and mortality globally, necessitating need for advancements of technologies for early therapeutics. Conventional detection methodologies often lag behind in terms of sensitivity, specificity, and cost-effectiveness, leading to delayed diagnosis and inadequate treatment. The need of advanced diagnostic techniques has considerably increased and led to the development of biosensors. Biosensing technologies offer several advantages over conventional methods hence, overcome limitations and improve diagnostic accuracy. Biosensors, particularly CRISPR-Cas based biosensors have emerged as a revolutionary technology for oncology diagnostics due to their high precision and adaptability. CRISPR-based biosensors provide remarkable precision, sensitivity, multiplexing capabilities, specificity, and rapidness for developing a cost-effective and portable point of care diagnostic device for cancer detection. In this review, we have discussed cancer pathogenicity, assessed the traditional detection techniques, and explored the advancements and advantages of biosensors, particularly CRISPR-based biosensors, in the detection of some major cancer types, namely lung, liver, colorectal, prostate, and cervical cancers. CRISPR-based biosensors represent a significant potential in cancer diagnostics, offering precise, cost-effective, and rapid detection of cancer biomarkers. The integration of CRISPR technology with biosensors holds substantial promise for enhancing early detection and improving patient outcomes in cancer diagnostics.

Crispr-cas biosensing for rapid detection of viral infection

With the frequent outbreaks of viral diseases globally, accurate and rapid diagnosis of viral infections is of significant importance for disease prevention and control. The CRISPR-Cas combined biosensing strategy, as an emergent nucleic acid detection technology, exhibits notable advantages including high specificity, elevated sensitivity, operational simplicity, and cost-effectiveness, thereby demonstrating significant potential in the domain of rapid viral diagnostics. This paper summarizes the principles of the CRISPR-Cas system, the novel biotechnologies, and the latest research progress in virus detection using the combined biosensing strategy. Additionally, this paper discusses the challenges faced by CRISPR-Cas biosensing strategies and outlines future development directions, which provides a reference for further research and clinical applications in the rapid diagnosis of viral infections.

Integrating Genomic Data with the Development of CRISPR-Based Point-of-Care-Testing for Bacterial Infections

Purpose of Review

Bacterial infections and antibiotic resistance contribute to global mortality. Despite many infections being preventable and treatable, the lack of reliable and accessible diagnostic tools exacerbates these issues. CRISPR (Clustered Regularly Interspaced Short Palindromic Repeats)-based diagnostics has emerged as a promising solution. However, the development of CRISPR diagnostics has often occurred in isolation, with limited integration of genomic data to guide target selection. In this review, we explore the synergy between bacterial genomics and CRISPR-based point-of-care tests (POCT), highlighting how genomic insights can inform target selection and enhance diagnostic accuracy.

Recent Findings

We review recent advances in CRISPR-based technologies, focusing on the critical role of target sequence selection in improving the sensitivity of CRISPR-based diagnostics. Additionally, we examine the implementation of these technologies in resource-limited settings across Asia and Africa, presenting successful case studies that demonstrate their potential.

Summary

The integration of bacterial genomics with CRISPR technology offers significant promise for the development of effective point-of-care diagnostics.