Ultrasensitive Chemiluminescence Biosensor for Nuclease and Bacterial Determination Based on Hemin-Encapsulated Mesoporous Silica Nanoparticles

作者：Zefeng Gu, Anchen Fu, Li Ye, Kudelaidi Kuerban, Yi Wang, Zhijuan Cao · 发表于：ACS Sensors · 年份：2019 · DOI：10.1021/acssensors.9b01303 · 被引用次数：71 · 研究领域：Advanced biosensing and bioanalysis techniques、Biosensors and Analytical Detection、bioluminescence and chemiluminescence research

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–H 2 O 2 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 10 1 to 10 9 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 i...