A Facile Method for the Non-Covalent Amine Functionalization of Carbon-Based Surfaces for Use in Biosensor...

Area of Science:

• Materials Science
• Nanotechnology
• Biomedical Engineering

Background:

• Graphene's unique electrical properties are crucial for affinity biosensors (GFETs, resistors).
• Maintaining these properties during surface functionalization is critical for sensor performance.
• Non-covalent functionalization offers an advantage over covalent methods for preserving graphene's electrical characteristics.

Purpose of the Study:

• To investigate drop-cast 1,5-diaminonaphthalene (DAN) as a method for non-covalent amine functionalization of graphene.
• To assess the suitability of DAN functionalization for subsequent attachment of receptor molecules in biosensor development.
• To evaluate the robustness of the DAN functional layer under conditions relevant to biosensor manufacturing.

Main Methods:

• Non-covalent functionalization of graphene surfaces using drop-cast 1,5-diaminonaphthalene (DAN).
• Characterization of DAN-functionalized graphene using X-ray photoelectron spectroscopy (XPS), Raman spectroscopy, and real-time resistance measurements.
• Assessment of receptor molecule attachment and functional layer stability through sequential solvent exposure tests.

Main Results:

• Successful non-covalent amine functionalization of graphene surfaces with DAN was achieved via a drop-casting method.
• Confirmation of successful modification and subsequent receptor molecule attachment using XPS, Raman spectroscopy, and resistance measurements.
• The DAN functional layer demonstrated robustness, remaining intact after multiple solvent wash steps.

Conclusions:

• Drop-cast DAN is a viable, rapid, and robust method for amine functionalization of graphene.
• This approach effectively prepares graphene surfaces for biosensor development while preserving electrical properties.
• The method's stability under washing conditions supports its application in biosensor manufacturing.