MSN/NA-doped nanoflower enhancing isothermal fluorescent sensor with a portable PCR tube fluorescence reader for the on-site detection of Vibrio parahaemolyticus.

To develop an on-site, thermostatic and rapid sensor for the detection of Vibrio parahaemolyticus (V. parahaemolyticus), A single cross-priming fluorescence (SCPF) sensor was designed using a 3D nano-nucleic acid hybrid material that termed mesoporous silica nanoparticle/nucleic acid-doped nanoflower (MSN/NA-doped nanoflower). In addition, a portable polymerase chain reaction (PCR) tube fluorescence reader was built. Further analysis of the MSN/NA-doped nanoflower morphology and the enhancement mechanism indicated that the MSNs aggregated into larger nanoclusters by adsorbing single cross-priming amplification (sCPA) components, forming MSNs/NAs-doped nanoflowers, and increasing the local concentrations to enhance sCPA efficiency. Cyclic amplification relied mainly on the self-folding hairpin-like structure of the amplified product that continuously formed, opened, re-formed, and opened again. The target DNA was detected with a detection limit of 2.4 copies/μL.