Integrated microfluidic cartridge for rapid and colorimetric detection of Mycoplasma pneumoniae

Abstract

Mycoplasma pneumoniae is a major cause of community-acquired pneumonia, yet its diagnosis remains challenging due to overlapping symptoms with other respiratory pathogens. In this study, an integrated microfluidic cartridge platform has been developed that combines three synergistic advancements: a chemical lysis reagent (GuHCl/EDTA) enabling direct genomic DNA release from M. pneumoniae collected by nasal swabs within 2 min without extraction steps, a novel dual-dye system (hydroxy naphthol blue/SYBR Green I) that leverages complementary fluorescence transitions from red to green for enhanced visual discrimination of loop-mediated isothermal amplification (LAMP) results, and a smartphone-based RGB quantification algorithm to standardize interpretation by analyzing colorimetric changes. The microfluidic cartridge integrates lysis, amplification, and detection into a closed workflow, achieving a sample-to-answer time of 40 min with a detection limit of 1 copy/μL. Clinical validation using 25 nasal swab samples demonstrated 95% sensitivity (19/20) and 100% specificity (5/5) compared with serological tests. This platform offers a rapid, cost-effective, and user-friendly solution for point-of-care diagnosis of M. pneumoniae, particularly in resource-limited settings.

Keywords: Mycoplasma pneumoniae; Colorimetric detection; Extraction-free analysis; Loop-mediated isothermal amplification; Microfluidic cartridge; POCT.