Strategic Design and Engineering of CRISPR/Cas-Powered Sensing Platforms for Enhanced Nucleic Acid Detection.

Rapid and accurate nucleic acid detection is fundamental to effective disease management. While PCR remains the gold standard, its requirement for sophisticated instrumentation limits its application in point-of-care settings. CRISPR-Cas systems have emerged as a disruptive diagnostic technology, leveraging the programmable specificity and unique trans-cleavage activity of Cas effectors to revolutionize biosensing. This review systematically evaluates the evolution of CRISPR-Cas-powered sensing platforms, categorized by their signal transduction modalities. We first discuss the expanding biochemical landscape of Cas nucleases, highlighting recent discoveries where conventional boundaries of Cas9, Cas12, and Cas13 have been transcended to enable versatile DNA/RNA targeting. Subsequently, we provide a comprehensive analysis of four primary sensing architectures: (1) Fluorescence-based platforms, exploring diverse strategies from target and signal amplification with dual-labeled ssDNA probes to nanomaterial-based probes; (2) Naked-eye visual platforms, encompassing both solid-phase lateral flow assays and solution-phase colorimetric strategies that facilitate rapid, instrument-free screening; (3) Electrochemical biosensors, which transduce biological recognition events into measurable electrical parameters, offering high sensitivity and seamless integration with miniaturized electronics; and (4) Electronic and Optoelectronic systems, including field-effect transistors and plasmonic sensors, which offer high-sensitivity, label-free detection. Despite significant progress, the translation of CRISPR-Dx from laboratory proof of concepts to clinical reality faces several bottlenecks. We critically analyze current challenges, including the need for integrated "sample-to-answer" workflows, high-throughput multiplexing, and digital quantification. Finally, we envision future trends such as AI-assisted signal processing and wearable sensing interfaces. By bridging the gap between molecular biology and advanced engineering, CRISPR-powered platforms are poised to make precision molecular diagnostics universally accessible.