期刊
ANALYTICA CHIMICA ACTA
卷 1036, 期 -, 页码 107-114出版社
ELSEVIER
DOI: 10.1016/j.aca.2018.06.060
关键词
Magnetic nanoparticles; Magnetic nanoparticles-DNA interactions; Aptasenosr; Lipopolysaccharide detection; Fluorescence
资金
- National Natural Science Foundation of China [81503086, 21672161]
- Tianjin University of Science and Technology (TUST) [20140520]
- a research funding of '1000 Talents Plan' of Tianjin
- Foundation of Key Laboratory of Industrial Fermentation Microbiology of Ministry of Education
- Tianjin Key Lab of Industrial Microbiology [2015IM106]
In current study, we have found that several magnetic nanoparticles (MNPs) are able to absorb DNA molecules, and surface engineering would be beneficial to tune such interaction. We then have focused on the assembly of polyethylenimine (PEI) coated MNPs (PEI-MNPs) with ssDNA (single-stranded DNA) and found this assembly is mediated by two forces, namely the electrostatic interactions of surface charges of MNPs and the phosphate backbones of DNA; as well as the coordination of exterior iron ions (especially Fe3+) of MNPs and DNA phosphate backbones. The fluorescence of dye-labeled DNA is significantly quenched when being complexed with PEI-MNPs, which is proved to be caused by static quenching. This PEI-MNPs interact with DNA, which could be harnessed for devising a novel type of aptasensor. This has been examplified by the selective and sensitive detection of lipopolysaccharide (LPS). The LOD (limit of detection) is similar to 35 ng/mL and the linear range from 50 ng/mL to 10 mu g/mL. Compared with widely used graphene oxide (GO)-ssDNA aptamer sensors, we also have demonstrated that the PEI-MNPs based sensor is able to better avoid non-specific DNA displacement by interfering proteins, generating more satisfactory signal-to-background ratio. Our proposed sensor could be a supplement to classic GO. DNA sensors. In summary, our work provides fundamental understanding of MNPs-DNA interactions and also paves the way for developing novel MNPs based sensing approaches, which would contribute to nano-bio interface and DNA-assisted bio-analysis, DNA-coordinated nano-materials and DNA-directed assembly. (c) 2018 Elsevier B.V. All rights reserved.
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