Laser Construction TiOx-Ag heterostructure interface for high sensitive coupling resonance enhanced fluorescence in bacterial nucleic acid amplification sensor chip

Coupled resonance at the noble metals and metal oxides heterogeneous interface can enhance the fluorescence of molecules. This fascinating direction provides high value for the preparation and engineering design of fluorescence sensing platforms in nucleic acid sensing, pathogen detection and biological imaging. Here, an integrated nucleic acid amplification sensor chip consists of an array of silver nanoparticles/oxygen vacancy titanium oxide (TiO x -Ag) heterostructure substrates. The femA gene of Staphylococcus aureus was amplified and detected by enhancement fluorescence on the integrated chip. The TiO x -Ag heterostructure array was prepared by a laser method, the enhanced fluorescence performance was investigated in detail using calcein as a probe. The optical, electronic structure and plasmonic local field analysis indicate the strong coupling between the fluorescence molecule and the TiO x -Ag crystal plane, which inspired the excellent fluorescence signal of calcein, with an enhancement factor of up to 5. Staphylococcus aureus was detected by the above chip with a detection limit as low as 157 cfu/mL. These methods were applied to the detection of spiked serum samples with good detected performances, providing a powerful tool for rapid and reliable diagnosis of pathogens in medical institutions.