Two-dimensional Layered MoS2 Biosensors Enable Highly Sensitive Detection of Biomolecules
Date of this Version
12-17-2014Abstract
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.
Discipline(s)
Diagnosis | Electrical and Electronics
Comments
This is the Publisher PDF of Lee, J; Dok, P; Lee, Y; Park, H; Choi, W; Alam, M; and Kim, S. "Two-dimensional Layered MoS2 Biosensors Enable Highly Sensitive Detection of Biomolecules." Scientific Reports, 4, 7352. 2014. Copyright Nature Publishing Group, available at http://dx.doi.org/10.1038/srep07352.