1,2,3-Triazole-linked DNA biosensors: molecular design to real-time applications.

Many aspects of modern life rely on rapid, accurate, and selective detection methodologies, especially for heavy toxins, pathogens, biomolecules, metal ions, and miRNAs. Thus, there is a need for reliable and versatile advanced biosensing platforms that can meet these challenges. CuAAC-assisted systems have emerged as efficient tools for constructing DNA biosensors due to their high efficiency, bioorthogonality, and site-specific conjugation capabilities. This review highlights the role of copper(i)-catalyzed azide-alkyne cycloaddition (CuAAC) in DNA biosensing platforms. Emphasis is placed on the use of CuAAC-aided 1,2,3-triazoles for different linkages, surface modifications and dual-strand linkages. Furthermore, the integration of click chemistry with nanomaterials, DNA-based structures, DNAzymes, CRISPR, and ATRP for signal amplification and highly sensitive detection is discussed. Various signal transduction mechanisms are included, such as fluorescence, electroluminescence, and electrochemical signal outputs. In addition, the review evaluates recent discoveries, underlying mechanisms and current limitations, enabling a more in-depth understanding of how click chemistry is reforming DNA-based biosensing. Overall, this work underscores the power of 1,2,3-triazole to enhance next-generation biosensors with improved sensitivity, selectivity, and real-world applicability.