Recent advances in highly sensitive and specific functional nucleic acid sensors for environmental pollutant detection: from mechanism to application.

Functional nucleic acids (FNAs) have emerged as a cutting-edge tool in environmental pollutant detection, attributed to their exceptional stability, robust specificity, and remarkable capacity for signal transduction and amplification. This review elaborates comprehensively on four pivotal categories of FNAs-aptamers, RNA-cleaving DNAzymes, G-quadruplex/hemin DNAzymes, and gRNAs-alongside their applications in monitoring a spectrum of pollutants. These encompass organic contaminants (e.g., pesticides and bisphenols), heavy metals (such as Pb2+ and Hg2+), biotoxins, and pathogenic microorganisms. It also underscores the integration of FNAs with sophisticated technologies like nanomaterials and CRISPR/Cas systems to augment detection sensitivity and efficacy. Despite prevailing challenges, including susceptibility to environmental variables (pH and temperature) and intricate synthesis procedures, FNAs hold immense potential for advancing environmental monitoring and pollution control.