CRISPR-based electrochemiluminescence biosensors: Principles, optimization strategies, and translational challenges - A review of recent progress.

The integration of CRISPR/Cas systems with electrochemiluminescence (ECL) has emerged as a promising strategy for constructing high-performance biosensing platforms. CRISPR systems, particularly Cas12a and Cas13a, offer programmable recognition of nucleic acid targets and activatable trans-cleavage activity. ECL provides sensitive signal readout with low background and wide dynamic range. As a narrative review, this article provides a comprehensive overview of recent advances in CRISPR-ECL biosensors, with an emphasis on optimization strategies and practical applications. We first discuss the working principles of Cas12a and Cas13a relevant to biosensing, highlighting their distinct kinetic properties, crRNA design considerations, and reaction condition requirements. We then examine optimization approaches at three interconnected levels: nucleic acid probe design (signal-on, signal-off, and auxiliary probes), sensing interface engineering (probe structures, luminophores, electrode materials, and magnetic nanomaterials), and cascade signal amplification (PCR, CHA, RCA, SDA, EDA, and RPA). Through cross-study comparison, we evaluate the strengths and limitations of different approaches and identify critical knowledge gaps. Their applications in detecting disease biomarkers, pathogen nucleic acids, environmental contaminants, and enzyme activities are summarized. Despite remarkable sensitivity achieved, challenges remain in assay time, reproducibility in complex matrices, and clinical validation. From industrialization and global health perspectives, regulatory approval, manufacturing scalability, cost control, and deployment in low-resource settings are also discussed. Finally, future directions toward simplified workflows, enhanced matrix robustness, standardized validation, multiplexed detection, and point-of-care compatible platforms are proposed. This review provides a structured reference and critical perspective for researchers working on CRISPR-ECL biosensing and related fields.