Optimized DNA-based bioassay for Leptospira interrogans detection: a novel platform for leptospirosis diagnosis

An optimized DNA-based bioassay for Leptospira interrogans detection has been developed. Electrochemical studies of the developed biosensor were done using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). Surface characterization of the biosensor was done using scanning electron microscopy (SEM). The biosensor showed specificity to L. interrogans as determined by specificity studies. The sensitivity of the biosensor was 264.5 µA/cm²/ng and lower limit of detection (LOD) was 0.015 ng/6 µl using CV. The biosensor was also validated with serum samples spiked with single-stranded leptospiral DNA. The developed biosensor also showed good stability for a period of 6 months at 4 °C as shown by the DPV analysis.