Abstract
Pseudomonas aeruginosa is a high-priority pathogen responsible for up to 23% of infections in intensive care units, yet current diagnostic methods remain hindered by multiday delays or high technical complexity. In this study, we report a rapid and highly sensitive biosensor based on nanoporous anodic alumina (NAA) capped with a specific oligonucleotide molecular gate targeting the phzA2 gene. The S3 biosensor achieved a limit of detection (LOD) of 0.153 ng μL(-1) for genomic DNA and an exceptional 28 CFU mL(-1) for direct bacterial detection without the need for prior DNA extraction. Validation in 63 clinical urine samples demonstrated a sensitivity of 91.67% and a specificity of 94.87% (AUC: 0.961, p-value < 0.0001). Furthermore, the sensor was integrated into Lateral Flow Assay (LFA), enabling the discrimination of positive and negative clinical samples in only 1 min with 100% specificity and 90.9% sensitivity. These results, combined with a one-year stability at 4 °C, position this gated-nanodevice as a robust and low-cost tool for Point-of-care (POC) diagnosis of P. aeruginosa infections.