Ultra-simple nucleic acid extraction using a polystyrene microplastic particles-thermal lysis system for rapid detection of pathogen in nasal mucus

Respiratory infections are a leading cause of death and disability globally and have become an important issue of public concern. Nucleic acid amplification test (NAAT) has been recognized as the gold standard for respiratory infection diagnosis, and played a critical role in epidemic control during the COVID-19 pandemic. However, the laborious nucleic acid extraction limits the application of NAAT in the on-site respiratory infection diagnosis, an effective approach for disease control and prevention. Herein, a polystyrene microplastic particle (PSMP)-thermal lysis system was established to extract nucleic acids from nasal mucus in 4 min simply and rapidly without sacrificing sensing performance. The PSMP-thermal lysis system showed a strong protein adsorption capacity, by which nearly eliminating the interference of protein content in nasal mucus on amplification reaction. Moreover, the PCR using this PSMP-thermal lysis system showed excellent selectivity and anti-jamming ability, as well as the high sensitivity comparable to that using commercial kits based on commonly used solid-phase extraction in detecting target pathogens in sticky nasal mucus with protein content of 25.11 μg/μL. Furthermore, the practical use investigation indicated the PCR assay using this system could accurately identify respiratory infection patients by detecting corresponding pathogens in clinical nasal mucus samples. This PSMP-thermal lysis system has the potential for pathogen detection in various respiratory secretions and is anticipated to substantially simplify molecular diagnosis of respiratory infections.