Highly Specific Antibiotic Detection on Water-Stable Black Phosphorus Field-Effect Transistors

Area of Science:

• Materials Science
• Chemical Sensors
• Nanotechnology

Background:

• Two-dimensional (2D) black phosphorus (BP) exhibits promising semiconducting properties for field-effect transistor (FET) sensors.
• The inherent instability of BP in aqueous environments limits its practical application in biosensing.
• Understanding BP's sensing mechanisms in water is crucial for developing reliable sensors.

Purpose of the Study:

• To develop a water-stable BP FET sensor for effective antibiotic detection.
• To investigate the surface engineering strategies for enhancing BP stability and performance in aqueous media.
• To elucidate the sensing mechanism of BP-based sensors for tetracycline detection.

Main Methods:

• Surface engineering of BP using Ag+ coordination and melamine cyanurate (MC) supramolecular passivation.
• Fabrication of a BP FET sensor integrated with molecularly imprinted polymers (MIPs) for tetracycline recognition.
• Performance evaluation including sensitivity, selectivity, response time, and stability studies.
• Investigation of sensing mechanisms through solution chemistry impact studies.

Main Results:

• The engineered BP sensor demonstrated enhanced stability in water.
• High sensitivity to tetracycline with a detection limit of 7.94 nM and rapid response (<6 s).
• Excellent selectivity against structurally similar antibiotics was achieved.
• A novel sensing mechanism based on the conjugation effect and electrostatic gating was proposed.

Conclusions:

• The developed surface engineering strategy effectively stabilizes 2D black phosphorus for aqueous applications.
• The BP FET sensor provides a sensitive and selective platform for antibiotic detection.
• This research offers new insights into FET sensing mechanisms and enables the use of BP in environmental and biological monitoring.