title: Sub-femtomolar DNA detection based on layered molybdenum disulfide/multi-walled carbon nanotube composites, Au nanoparticle and enzyme multiple signal amplification.
abstract: A novel 2-dimensional graphene analog molybdenum disulfide/multi-walled carbon nanotube (MoS2/MWCNT) was synthesized by a simple hydrothermal method to achieve excellent electrochemical properties. An ultrasensitive electrochemical DNA biosensor was subsequently constructed by assembling a thiol-tagged DNA probe on a MoS2/MWCNT and gold nanoparticle (AuNP)-modified electrode that has already been coupled with glucose oxidase (GOD). In this work, GOD was used as a redox marker. The heteronanostructure formed on the biosensor surface appeared relatively good conductor for accelerating the electron transfer, while the modification of GOD and AuNPs provided multiple signal amplification for electrochemical biosensing. The multiple signal amplification strategy produced an ultrasensitive electrochemical detection of DNA down to 0.79 fM with a linear range from 10 fM to 10(7)fM, and appeared high selectivity to differentiate three-base mismatched DNA and one-base mismatched DNA. The developed approach provided a simple and reliable method for DNA detection with high sensitivity and specificity, and would open new opportunities for sensitive detection of other biorecognition events.
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China. Electronic address: kejinghuang@163.com.
authors.forename: Ke-Jing
authors.initials: KJ
authors.lastname: Huang
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
authors.forename: Yu-Jie
authors.initials: YJ
authors.lastname: Liu
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
authors.forename: Hai-Bo
authors.initials: HB
authors.lastname: Wang
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
authors.forename: Ya-Ya
authors.initials: YY
authors.lastname: Wang
authors.affiliation: College of Chemistry and Chemical Engineering, Xinyang Normal University, Xinyang 464000, China.
authors.forename: Yan-Ming
authors.initials: YM
authors.lastname: Liu
mesh_terms: D015374:Biosensing Techniques / Q000295:instrumentation; D003217:Conductometry / Q000295:instrumentation*; D004247:DNA / Q000032:analysis* / Q000235:genetics*; D004220:Disulfides / Q000737:chemistry; D004867:Equipment Design; D019544:Equipment Failure Analysis; D006046:Gold; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000648:ultrastructure; D008832:Microchemistry / Q000295:instrumentation; D008982:Molybdenum / Q000737:chemistry*; D053761:Nanocomposites / Q000737:chemistry / Q000648:ultrastructure; D037742:Nanotubes, Carbon / Q000737:chemistry* / Q000648:ultrastructure; D021141:Nucleic Acid Amplification Techniques / Q000295:instrumentation*; D020411:Oligonucleotide Array Sequence Analysis / Q000295:instrumentation; D015203:Reproducibility of Results; D012680:Sensitivity and Specificity
chemical_list: D004220:Disulfides; D037742:Nanotubes, Carbon; D006046:Gold; D008982:Molybdenum; D004247:DNA
keywords: Au nanoparticle; DNA biosensor; Glucose oxidase; Layered molybdenum disulfide/multi-walled carbon nanotube composites; Multiple signal amplification