title: Magnetic graphitic nanocapsules for programmed DNA fishing and detection.
abstract: Graphene nanomaterials are typically used in biosensing applications, and they have been demonstrated as good fluorescence quenchers. While many conventional amplification platforms are available, developing new nanomaterials and establishing simple, enzyme-free and low-cost strategies for high sensitivity biosensing is still challenging. Therefore, in this work, a core-shell magnetic graphitic nanocapsule (MGN) material is synthesized and its capabilities for the detection of biomolecules are investigated. MGN combines the unique properties of graphene and magnetic particles into one simple and sensitive biosensing platform, which quenches around 98% of the dye fluorescence within minutes. Based on a programmed multipurpose DNA capturing and releasing strategy, the MGN sensing platform demonstrates an outstanding capacity to fish, enrich, and detect DNA. Target DNA molecules as low as 50 pM could be detected, which is 3-fold lower than the limit of detection commonly achieved by carbon nanotube and graphene-based fluorescent biosensors. Moreover, the MGN platform exhibits good sensing specificity against DNA mismatch tests. Overall, therefore, these magnetic graphitic nanocapsules demonstrate a promising tool for molecular disease diagnosis and biomedicine. This simple fishing and enrichment strategy may also be extended to other biological and environmental applications and systems.
authors.affiliation: Molecular Science and Biomedicine Laboratory, State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University, Changsha, PR China.
authors.forename: Zhi-Ling
authors.initials: ZL
authors.lastname: Song
authors.forename: Xu-Hua
authors.initials: XH
authors.lastname: Zhao
authors.forename: Wei-Na
authors.initials: WN
authors.lastname: Liu
authors.forename: Ding
authors.initials: D
authors.lastname: Ding
authors.forename: Xia
authors.initials: X
authors.lastname: Bian
authors.forename: Hao
authors.initials: H
authors.lastname: Liang
authors.forename: Xiao-Bing
authors.initials: XB
authors.lastname: Zhang
authors.forename: Zhuo
authors.initials: Z
authors.lastname: Chen
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
mesh_terms: D015374:Biosensing Techniques; D004247:DNA / Q000032:analysis*; D006108:Graphite / Q000737:chemistry*; D057230:Limit of Detection; D008280:Magnetics; D053769:Nanocapsules
chemical_list: D053769:Nanocapsules; D006108:Graphite; D004247:DNA