{'fraction_non_alphanumeric': 0.026984126984126985, 'fraction_numerical': 0.014285714285714285, 'mean_word_length': 5.431972789115647, 'pattern_counts': {'":': 0, '<': 0, '<?xml version=': 0, '>': 0, 'https://': 0, 'lorem ipsum': 0, 'www.': 0, 'xml': 0}, 'pii_count': 0, 'substrings_counts': 0, 'word_list_counts': {'cursed_substrings.json': 0, 'profanity_word_list.json': 0, 'sexual_word_list.json': 0, 'zh_pornsignals.json': 0}}
Ultra-Sensitive Chemiluminescence Biosensor for Nuclease and Bacteria Determination Based on Hemin-Encapsulated Mesoporous Silica Nanoparticle.

Bacteria determination, emerging as a critical step in the understanding of the increasingly serious bacterial contaminations, remains a major challenge. Herein, a novel chemiluminescence biosensor was exploited for the ultra-sensitive 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/sigmoidal relationship between CL intensity and DNA nuclease/bacteria concentration, the as-prepared CL biosensor could detect S1 nuclease activity in the concentration of 0.01-10.0 U with the detection limit of 0.1 mU, and Escherichia coli O157:H7 (E. coli) or Stahylococcus aureus (S. aureus) concentration ranges of 101-109 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 works. Thus, this detection method could reach 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.