Timely detection of Staphylococcus aureus ( S. aureus ) is critical because it can multiply to disease-causing levels in a matter of hours. Herein, a simple and sensitive DNA tetrahedral (Td) fluorescence signal amplifier with blue carbon quantum dots (bCDs) was prepared for sandwich detection of S. aureus . bCD was modified at the apex of Td, and an aptamer on Td was used to accurately identify and "adsorb" the amplifier to the surface of S. aureus . Atomic force microscopy (AFM) demonstrates the successful preparation of this signal amplifier. The fluorescence intensity emitted in this strategy increased 4.72 times. The strategy showed a stronger fluorescence intensity change, sensitivity (linear range of 7.22 × 10 0 -1.44 × 10 9 CFU/mL with a LOD of 4 CFU/mL), and selectivity. The recovery rate in qualified pasteurized milk and drinking water samples was 96.54% to 104.72%. Compared with simple aptamer sandwich detection, these fluorescence signal amplifiers have improved fluorescence detection of S. aureus . Additionally, this fluorescent signal amplification strategy may be applied to the detection of other food pathogens or environmental microorganisms in the future.
Keyphrases
- label free
- single molecule
- staphylococcus aureus
- energy transfer
- atomic force microscopy
- loop mediated isothermal amplification
- quantum dots
- real time pcr
- gold nanoparticles
- escherichia coli
- multidrug resistant
- current status
- biofilm formation
- climate change
- nucleic acid
- pseudomonas aeruginosa
- candida albicans
- methicillin resistant staphylococcus aureus
- low birth weight
- circulating tumor cells