Quasi-Two-Dimensional Metal Oxide Semiconductors Based Ultrasensitive Potentiometric Biosensors

Abstract

Ultrasensitive field-effect transistor-based biosensors using quasi-two-dimensional metal oxide semiconductors were demonstrated. Quasi-two-dimensional low-dimensional metal oxide semiconductors were highly sensitive to electrical perturbations at the semiconductor-bio interface and showed competitive sensitivity compared with other nanomaterial-based biosensors. Also, the solution process made our platform simple and highly reproducible, which was favorable compared with other nanobioelectronics. A quasi-two-dimensional InO-based pH sensor showed a small detection limit of 0.0005 pH and detected the glucose concentration at femtomolar levels. Detailed electrical characterization unveiled how the device's parameters affect the biosensor sensitivity, and lowest detectable charge was extrapolated, which was consistent with the experimental data.

Non-Carbon 2D Materials-Based Field-Effect Transistor Biosensors: Recent Advances, Challenges, and Future Perspectives

“…Due to their specific structures and electrical characteristics, metal oxides have been considered as candidates to extend the library of 2D materials for transistors with a large band gap energy range (2.3–4.9 eV) and high electron mobilities (>10 cm 2 V −1 s −1 ) which guarantee high sensitivity and signal-to-noise ratio in biosensing. Moreover, FETs of these materials can be processed at moderate temperatures from solutions facilitating deposition on a large scale economically and the conductivity tuned by varying crystal size, morphology, dopant, contact geometry and temperature of operation [ 46 , 102 , 103 ]. Metal oxides, to date, have been applied as electrochemical and photoelectrochemical transducers for bio/chemical sensing [ 30 , 103 , 104 , 105 , 106 ] and FET transducer for sensing of gases [ 107 , 108 ].…”

“…When considering various metal oxides, In 2 O 3 has yielded many FET biosensors with good performance. Chen et al [ 46 ] presented a 2D In 2 O 3 -based FET biosensor which achieved specific detection of glucose with an extremely low limit of detection (<7 fM) and showed high sensitivity. Boronic acid and glucose, respectively, acted as the receptor and target molecules ( Figure 7 a).…”

“… Schematic of In 2 O 3 FET biosensors. ( a ) Illustration of the principle of glucose sensing on boronic acid-functionalized surface and responses to various concentrations of glucose [ 46 ]. Reprinted with permission from ref [ 46 ].…”

Artificial visual systems enabled by quasi–two-dimensional electron gases in oxide superlattice nanowires

“…Strong electron correlations in these atomically abrupt oxide heterointerfaces can give rise to a rich variety of electronic phases, which makes these quasi-2DEGs highly susceptible to small changes of control parameters (e.g., electric field, magnetic field, or light irradiation) (7,8,11). Interactions between these quasi-2DEGs and control parameters would create advanced optoelectronic devices with tunable properties, e.g., nonvolatile resistive switching (12), ultrasensitive potentiometric biosensing (13), and giant persistent photoconductivity (PPC) (14). Given the high carrier mobility together with the high sensitivity to various stimuli, quasi-2DEG systems are anticipated to enable technological breakthroughs in the development of neuromorphic sensing systems, which can substantially lower energy consumption and enhance sensitivity that are not achievable by other material systems.…”

Facile fabrication of wire-type indium gallium zinc oxide thin-film transistors applicable to ultrasensitive flexible sensors

“…Biosensors constitute a new paradigm in medical technology. Biosensors detect biological elements, affording prompt and accurate diagnoses at low cost 3 , 4 . Especially, field-effect transistor (FET)-based biosensors have been intensively investigated because they afford the advantages of direct transduction and high sensitivity at a low driving voltage 5 , 6 .…”