With zoonotic outbreaks on the rise, rapid and accurate infectious disease diagnostics are critical for both human and animal health. Traditional lateral flow assays lack sensitivity and specificity, while isothermal amplification methods like LAMP, though rapid, can be hindered by optical detection issues. We present an electrochemical nucleic acid amplification test (NAAT) that combines isothermal amplification with real-time voltammetric detection. This novel method relies on monitoring of amplification-associated proton release through redox probing of a pH-sensing compound. The method shows high concordance with RT-qPCR under the tested conditions and demonstrates a limit of detection (LOD) of 50 copies/reaction for IAV. In RNA purified from clinical samples, 231/234 (98.7%) are concordant with RT-qPCR for SARS-CoV-2, IAV, IBV, or RSV A. In a proof-of-concept extraction-free workflow, 14/14 equine nasal swab samples are correctly classified for EHV-5 relative to qPCR. Together, these data support the feasibility of real-time voltammetric LAMP across several sample types, while broader point-of-care validation across additional matrices and prospective cohorts remains to be established.
Munita et al. (Mon,) studied this question.