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Dopamine coated Fe3O4 nanoparticles as enzyme mimics for the sensitive detection of bacteria.

ABSTRACT: We report a simple and economical colorimetric bacterial sensing strategy with catalytic amplification using dopamine-capped iron oxide (Dop-Fe3O4) nanoparticles. These nanoparticles catalyse the oxidation of a chromogenic substrate in the presence of H2O2 into a green colored product. The catalytic activity of the nanoparticles is inhibited in the presence of bacteria, providing naked eye detection of bacteria at 104 cfu mL-1 and by spectrophotometric detection down to 102 cfu mL-1.

SUBMITTER: Mumtaz S

PROVIDER: S-EPMC5690545 | biostudies-literature | 2017 Nov

REPOSITORIES: biostudies-literature

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Dopamine coated Fe3O4 nanoparticles as enzyme mimics for the sensitive detection of bacteria.

Mumtaz Shazia S Wang Li-Sheng LS Hussain Syed Zajif SZ Abdullah Muhammad M Huma Zille Z Iqbal Zafar Z Creran Brian B Rotello Vincent M VM Hussain Irshad I

Chemical communications (Cambridge, England) 20171101 91

We report a simple and economical colorimetric bacterial sensing strategy with catalytic amplification using dopamine-capped iron oxide (Dop-Fe3O4) nanoparticles. These nanoparticles catalyse the oxidation of a chromogenic substrate in the presence of H2O2 into a green colored product. The catalytic activity of the nanoparticles is inhibited in the presence of bacteria, providing naked eye detection of bacteria at 104 cfu mL-1 and ...[more]

PMID: 29094116

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