A portable smartphone-based electrochemiluminescence device integrated with bipolar electrode detection chip for multi-target respiratory pathogen detection.

At-home nucleic acid testing enables early detection of respiratory pathogens, making it crucial for infection control and community transmission reduction, particularly in resource-limited settings. This research develops a system for field-based multiplex respiratory pathogen detection: 1) A portable smartphone-based electrochemiluminescence (ECL) detection device (termed as the PEMD), constructed using LEGO blocks, capable of precise temperature control for Loop-mediated isothermal amplification (LAMP), and equipped with a custom-developed smartphone app for accurate collection and automatic processing of ECL signals; 2) A bipolar electrode and position-resolved ECL sensor chip (termed as the B-chip) that links adjacent amplification and detection zones in series, using DNA-binding redox probe to detect quenching of the ECL signal in positive samples. The system can simultaneously detect H1N1, H7N9, influenza B, and human adenovirus, with a detection limit of 10 copies/μL in simulated samples, and identify 87.5 % of positive samples and 91.7 % of negative samples in clinical samples in good agreement with the gold standard qPCR method. This system shows high sensitivity, specificity, and rapid detection, integrates smartphone imaging and cloud analysis, making it a powerful tool for multiplex respiratory pathogen detection and point-of-care diagnostics.