Sensitive detection of infectious disease utilizing carbon Sphere@Fe₃O₄ micromotor combined with graphene...

Rapid on-site detection of infectious diseases is considerably essential for preventing and controlling major epidemics and maintaining social and public safety. However, the complexity of the natural environment in which infectious disease pathogens exist severely disrupts the performance of on-site detection, and rapid detection can become meaningless because of the cumbersome sample pretreatment process.

Herein, a new detection platform based on a carbon sphere@Fe₃O₄ micromotor (CS@Fe₃O₄) in combination with a graphene field-effect transistor (GFET) was designed and used for the on-site detection of SARS-CoV-2 coronavirus pathogens. The CS@Fe₃O₄ micromotor, surface-modified with anti-SARS-CoV-2 coronavirus antibody, could move at a velocity of 79.4 μm/s in a solution containing hydrogen peroxide (H₂O₂) and exhibited capture rates of 67.9% and 36.2% for the SARS-CoV-2 pathogen in phosphate buffered saline (PBS) and soil solutions, respectively. After magnetic field separation, the captured micromotor was used for GFET detection, with detection limits of 4.6 and 15.6 ag/mL in PBS and soil solutions, respectively.

This detection platform can be employed to avoid complex sample pretreatment procedures and achieve rapid on-site detection of SARS-CoV-2 coronavirus pathogens in complex environments. This study introduces a novel approach for the on-site detection of infectious diseases.