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Updated: Jan 21, 2026
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Ultrasensitive Detection of Biomarkers by Using a Molecular Imprinting Based Capacitive Biosensor
Published on: February 16, 2018
12.6K
Quantum capacitance-limited MoS2 biosensors enable remote label-free enzyme measurements
Son T Le1, Nicholas B Guros2, Robert C Bruce3
1Nanoscale Device Characterization Division, National Institute of Standards and Technology, Gaithersburg, MD 20899, USA and Theiss Research, La Jolla, CA 92037, USA.
Nanoscale
|August 14, 2019
Summary
We developed novel field-effect transistors (FETs) using molybdenum disulfide (MoS2) for highly sensitive pH detection. These biosensors offer significantly improved resolution for applications in diagnostics and drug development.
Area of Science:
- Materials Science
- Nanotechnology
- Biotechnology
Background:
- Accurate pH monitoring is crucial in biotechnology and diagnostics.
- Conventional sensors have limitations in sensitivity and resolution.
- Field-effect transistors (FETs) offer potential for enhanced biosensing.
Purpose of the Study:
- To develop highly sensitive and high-resolution pH-detecting biosensors.
- To demonstrate the application of these biosensors in quantifying enzyme kinetics.
- To explore their utility in early disease diagnostics and therapeutic development.
Main Methods:
- Fabrication of atomically thin FETs using monolayer MoS2.
- Utilization of a room temperature ionic liquid (RTIL) as a gate dielectric.
- Remote gate connection to a pH sensing element for device reusability.
Main Results:
- Achieved 75-fold higher pH sensitivity (≈4.4 V/pH) compared to the Nernst limit.
- Demonstrated a pH resolution of 92 × 10^-6 at 10 Hz with low intrinsic noise.
- Successfully quantified kinase Cdk5 activity at sub-physiological concentrations with high temporal resolution.
Conclusions:
- Atomically thin MoS2 FETs with RTIL gates provide unprecedented pH sensitivity and resolution.
- The developed biosensor platform enables rapid kinetic analysis of enzymes.
- This technology holds promise for early diagnostics of neurological conditions and development of novel therapeutics.
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