title: A label-free ultrasensitive electrochemical DNA sensor based on thin-layer MoS2 nanosheets with high electrochemical activity.
abstract: A label-free and ultrasensitive electrochemical DNA biosensor, based on thin-layer molybdenum disulfide (MoS2) nanosheets sensing platform and differential pulse voltammetry detection, is constructed in this paper. The thin-layer MoS2 nanosheets were prepared via a simple ultrasound exfoliation method from bulk MoS2, which is simpler and no distortion compared with mechanical cleavage and lithium intercalation. Most importantly, this procedure allows the formation of MoS2 with enhanced electrochemical activity. Based on the high electrochemical activity and different affinity toward ssDNA versus dsDNA of the thin-layer MoS2 nanosheets sensing platform, the tlh gene sequence assay can be performed label-freely from 1.0 × 10(-16)M to 1.0 × 10(-10)M with a detection limit of 1.9 × 10(-17)M. Without labeling and the use of amplifiers, the detection method described here not only expands the application of MoS2, but also offers a viable alternative for DNA analysis, which has the priority in sensitivity, simplicity, and costs. Moreover, the proposed sensing platform has good electrocatalytic activity, and can be extended to detect more targets, such as guanine and adenine, which further expands the application of MoS2.
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker of Education Ministry, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors.forename: Xinxing
authors.initials: X
authors.lastname: Wang
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker of Education Ministry, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors.forename: Fuxin
authors.initials: F
authors.lastname: Nan
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker of Education Ministry, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors.forename: Jinlong
authors.initials: J
authors.lastname: Zhao
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker of Education Ministry, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China. Electronic address: taoyang@qust.edu.cn.
authors.forename: Tao
authors.initials: T
authors.lastname: Yang
authors.affiliation: Huangdao Entry-Exit Inspection and Quarantine Bureau, Qingdao 266555, PR China.
authors.forename: Tong
authors.initials: T
authors.lastname: Ge
authors.affiliation: Key Laboratory of Sensor Analysis of Tumor Marker of Education Ministry, College of Chemistry and Molecular Engineering, Qingdao University of Science and Technology, Qingdao 266042, PR China.
authors.forename: Kui
authors.initials: K
authors.lastname: Jiao
mesh_terms: D015374:Biosensing Techniques; D004277:DNA, Single-Stranded / Q000737:chemistry / Q000302:isolation & purification*; D004220:Disulfides / Q000737:chemistry*; D055664:Electrochemical Techniques; D057230:Limit of Detection; D008982:Molybdenum / Q000737:chemistry*; D049329:Nanostructures
chemical_list: D004277:DNA, Single-Stranded; D004220:Disulfides; D008982:Molybdenum; C082964:molybdenum disulfide
keywords: Electrochemical DNA sensor; High electrochemical activity; Label-free; Thin-layer MoS(2) nanosheets; Ultrasensitive