Ultrasensitive Chemiluminescence Biosensor for Nuclease and Bacterial Determination Based on Hemin-Encapsulated Mesoporous Silica Nanoparticles.
Zefeng GuAnchen FuLi YeKudelaidi KuerbanYi WangZhijuan CaoPublished in: ACS sensors (2019)
Bacterial determination, emerging as a critical step in the understanding of increasingly serious bacterial contaminations, remains a major challenge. Herein, a novel chemiluminescence biosensor was exploited for the ultrasensitive determination of nuclease activity and bacteria, in which, hemin, the chemiluminescent (CL) tag molecule was encapsulated into ordered mesopores of mesoporous silica nanoparticles with a specific DNA gate. The capped DNA could be specifically switched upon exposure to the DNA nuclease or bacterial lysate and allowed for an increased release of the encapsulated hemin, which therefore resulted in an obviously enhanced CL signal for the luminol-H2O2 system. Attributed to this unique behavior with the linear or sigmoidal relationship between CL intensity and DNA nuclease or bacterial concentration, the as-prepared CL biosensor could detect S1 nuclease activity in the concentration range 0.01-10.0 U with a detection limit of 0.1 mU, and Escherichia coli O157:H7 (E. coli) or Staphylococcus aureus (S. aureus) in the concentration ranges 101 to 109 cfu mL-1. The detection limit of E. coli and S. aureus was calculated to be 3.0 and 2.5 cfu mL-1, respectively, which was comparable or even better than that of previous studies. Thus, this detection method could achieve detectable levels without cell enrichment overnight. Moreover, the proposed biosensing system could be conducted in the homogeneous solution without separation and washing, greatly improving the reaction efficiency and simplifying the procedure. As expected, the novel CL biosensor promised a great potential for simple and convenient detection of nuclease and bacteria in fields such as food bacterial contamination, pharmaceuticals, and clinical analysis.
Keyphrases
- label free
- escherichia coli
- sensitive detection
- gold nanoparticles
- molecularly imprinted
- circulating tumor
- loop mediated isothermal amplification
- dna binding
- quantum dots
- staphylococcus aureus
- cell free
- single molecule
- solid phase extraction
- stem cells
- real time pcr
- risk assessment
- human health
- drinking water
- multidrug resistant
- mesenchymal stem cells
- single cell
- transcription factor
- climate change
- minimally invasive
- heavy metals
- walled carbon nanotubes