DNAzyme-Based Point-of-Care Diagnosis of Aggressive Periodontitis.

The rapid and accurate detection of Aggregatibacter actinomycetemcomitans (AA), a key pathogen in aggressive periodontitis, remains a critical challenge in point-of-care diagnostics. Here, we report the development of a portable lateral flow device (LFD) using an RNA-cleaving DNAzyme (RCD-AA5) as a highly specific molecular recognition element. Selected via systematic evolution of ligands by exponential enrichment (SELEX) against AA crude extracellular mixture (CEM-AA), RCD-AA5 demonstrated exceptional specificity, distinguishing the target from seven other Gram-negative and Gram-positive bacteria. A truncated 77-nt variant (RCD-AA5t5) retained full functionality while improving practical applicability. The resulting LFD exhibited 100% sensitivity and 100% specificity for identifying AA in clinical saliva samples. This work establishes a novel, DNAzyme-powered diagnostic platform that enables rapid, user-friendly, and accurate detection of AA, offering significant potential for improving aggressive periodontitis diagnosis in resource-limited and clinical setting.