Fabrication and comparison of MoS2 and WSe2 field-effect transistor biosensors

Abstract

The authors present a study on the evolution behaviors of the transfer characteristics of MoS2 and WSe2 field-effect transistor biosensors when they are subjected to tumor necrosis factor-alpha and streptavidin solutions with varying analyte concentrations. Both MoS2 and WSe2 sensors exhibit very low detection limits (∼60 fM for tumor necrosis factor-alpha detection; ∼70 fM for streptavidin detection). However, WSe2 sensors exhibit the higher linear-regime sensitivities in comparison with MoS2 sensors. In particular, WSe2 sensors exhibit high linear-regime sensitivities up to ∼1.54%/fM for detecting streptavidin at a concentration of ∼70 fM. Such relatively higher sensitivities obtained from WSe2 sensors are attributed to their intrinsic ambipolar transfer characteristics, which make their ON-state carrier concentrations significantly lower than those of MoS2 sensors, and therefore, the target-molecule-induced doping effect results in more prominent channel conductance modulation in WSe2 transistor sensors than in MoS2 sensors. Furthermore, this work strongly implies that the target-molecule-induced surface scattering also plays an important role in determining the response behaviors of the sensors made from atomically layered materials. Especially, the competition between target-molecule-induced p-doping and surface-scattering effects is responsible for the sensor behavior variation observed in the p-type conduction branch of WSe2 sensors. This work advances the critical device physics highly relevant with the fabrication and implementation of reliable nanoelectronic biosensors based on emerging atomically layered semiconductors.

Optical fingerprints and electron transport properties of DNA bases adsorbed on monolayer MoS2

“…the photoluminescence spectra (PL) of MoS 2 reveals the possibility of optical biosensors 19 ; modulation in PL due to the presence of DNA base could serve as a fingerprint for selective optical biosensing 19 ; nano-pore in pristine MoS 2 results in fast detection of DNA bases 17 ; MoS 2 based biomedical sensor shows promise to detect DNA origami, tumor necrosis factor-alpha (TNF-a) molecules etc. [21][22][23][24][25] .…”

Field-effect sensors – from pH sensing to biosensing: sensitivity enhancement using streptavidin–biotin as a model system

“…Measurements in this region of operation have been reported which show detection of streptavidin at the oxide-APTES-biotin interface. 25,35,44,49,120 Data from these publications is tabulated in ESI sections 5 and 9. † Three publications contained data with response as a function of streptavidin concentration, giving a Sensitivity of 72%, 162 63% 120 and 0.5%.…”

“…26,28,32,36,49,51,107,120,[160][161][162][163][164][165][166] The simplest model for biomolecule-binding reactions, is the first-order Langmuir model of surface-reactions (details in ESI section 10 †). In this model the surface reaction of analyte (A) to the surface sites (S) is treated simply:…”

Scalable Production of Molybdenum Disulfide Based Biosensors

“…, MoS 2 ) may exhibit better performance than graphene for this application. 5,6 However, reproducible, high-yield fabrication processes are necessary for this emerging technology.…”