期刊
MICROCHIMICA ACTA
卷 189, 期 12, 页码 -出版社
SPRINGER WIEN
DOI: 10.1007/s00604-022-05571-4
关键词
Bacteria; Mimetic enzyme; CuO; Fluorimetry; Portable device; Smartphone-based detection
资金
- National Natural Science Foundation of China [21675056]
A label-free biosensor based on cupric oxide nanoparticles was developed for selective detection of Gram-negative bacteria. The biosensor showed good performance in detecting bacteria in food and water samples, and a portable smartphone-based device was also designed for on-site detection.
A label-free biosensor based on cupric oxide (CuO) nanoparticles was constructed for the selective detection of Gram-negative bacteria. CuO possesses oxidase-like activity and can catalyze the oxidation of o-phenylenediamine (OPD) to produce oxidized OPD, which has a fluorescence emission at 573 nm under excitation at 423 nm. The mechanism study suggests that the oxygen vacancies of CuO can activate the dissolved oxygen to form superoxide anions, which in turn oxidize OPD. Gram-negative bacteria can reduce part of Cu(II) in CuO to Cu(I) based on their copper homeostasis system, thus inhibiting the oxidation of OPD and decreasing the fluorescence intensity of the catalytic system. This principle was utilized to construct a biosensor to realize the selective detection of Gram-negative bacteria successfully. The biosensor exhibited a good linear correlation toward the logarithm concentration of three Gram-negative bacteria with R-2 >= 0.985. It was applied to detect three Gram-negative bacteria in eggshell, Chinese cabbage, and the Pearl River water samples, with recoveries ranging from 92.4 to 107%. Moreover, a smartphone-based portable device was designed and fabricated to realize the on-site detection of bacteria. The results of the portable device were comparable to those of fluorescence spectrophotometry, suggesting that the portable device has tremendous potential in the on-site detection of bacteria.
作者
我是这篇论文的作者
点击您的名字以认领此论文并将其添加到您的个人资料中。
推荐
暂无数据