title: Two-dimensional layered MoS₂ biosensors enable highly sensitive detection of biomolecules.
abstract: We present a MoS2 biosensor to electrically detect prostate specific antigen (PSA) in a highly sensitive and label-free manner. Unlike previous MoS2-FET-based biosensors, the device configuration of our biosensors does not require a dielectric layer such as HfO2 due to the hydrophobicity of MoS2. Such an oxide-free operation improves sensitivity and simplifies sensor design. For a quantitative and selective detection of PSA antigen, anti-PSA antibody was immobilized on the sensor surface. Then, introduction of PSA antigen, into the anti-PSA immobilized sensor surface resulted in a lable-free immunoassary format. Measured off-state current of the device showed a significant decrease as the applied PSA concentration was increased. The minimum detectable concentration of PSA is 1 pg/mL, which is several orders of magnitude below the clinical cut-off level of ~4 ng/mL. In addition, we also provide a systematic theoretical analysis of the sensor platform - including the charge state of protein at the specific pH level, and self-consistent channel transport. Taken together, the experimental demonstration and the theoretical framework provide a comprehensive description of the performance potential of dielectric-free MoS2-based biosensor technology.
authors.affiliation: Multi-Functional Nano/Bio Electronics Lab., Department of Electronics and Radio Engineering, Kyung Hee University, Gyeonggi 446-701, South Korea.
authors.forename: Joonhyung
authors.initials: J
authors.lastname: Lee
authors.affiliation: School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Piyush
authors.initials: P
authors.lastname: Dak
authors.affiliation: Multi-Functional Nano/Bio Electronics Lab., Department of Electronics and Radio Engineering, Kyung Hee University, Gyeonggi 446-701, South Korea.
authors.forename: Yeonsung
authors.initials: Y
authors.lastname: Lee
authors.affiliation: Multi-Functional Nano/Bio Electronics Lab., Department of Electronics and Radio Engineering, Kyung Hee University, Gyeonggi 446-701, South Korea.
authors.forename: Heekyeong
authors.initials: H
authors.lastname: Park
authors.affiliation: School of Advanced Materials Engineering, Kookmin University, Seoul 136-702, Korea.
authors.forename: Woong
authors.initials: W
authors.lastname: Choi
authors.affiliation: School of Electrical and Computer Engineering, Purdue University, West Lafayette, IN 47907, USA.
authors.forename: Muhammad A
authors.initials: MA
authors.lastname: Alam
authors.affiliation: Multi-Functional Nano/Bio Electronics Lab., Department of Electronics and Radio Engineering, Kyung Hee University, Gyeonggi 446-701, South Korea.
authors.forename: Sunkook
authors.initials: S
authors.lastname: Kim
mesh_terms: D015374:Biosensing Techniques / Q000379:methods*; D004220:Disulfides / Q000737:chemistry* / Q000276:immunology*; D004867:Equipment Design / Q000379:methods; D006801:Humans; D006863:Hydrogen-Ion Concentration; D007118:Immunoassay / Q000379:methods*; D008297:Male; D008982:Molybdenum / Q000737:chemistry* / Q000276:immunology*; D017430:Prostate-Specific Antigen / Q000737:chemistry* / Q000276:immunology*; D011471:Prostatic Neoplasms / Q000175:diagnosis*; D012680:Sensitivity and Specificity
chemical_list: D004220:Disulfides; D008982:Molybdenum; D017430:Prostate-Specific Antigen; C082964:molybdenum disulfide