Surface Functionalized Graphene Biosensor on Sapphire for Cancer Cell Detection

Area of Science:

• Materials Science
• Biotechnology
• Nanotechnology

Background:

• Graphene's unique 2D structure, optical transparency, and high carrier mobility make it suitable for electrical biosensing.
• Existing biosensing methods face challenges in detecting large analytes like cancer cells.

Purpose of the Study:

• To develop and evaluate bio-functionalized graphene electrical biosensors for detecting human colorectal carcinoma cells.
• To assess the potential of these sensors for detecting circulating tumor cells (CTCs).

Main Methods:

• Graphene films were grown using catalyst-free chemical vapor deposition (CVD) on sapphire substrates.
• Raman spectroscopy and atomic force microscopy (AFM) confirmed single/few-layer graphene.
• Electrical biosensors were fabricated and bio-functionalized with antibodies for cell capture.

Main Results:

• The functionalized graphene sensors detected human colorectal carcinoma cells by measuring resistance changes.
• An increase in resistance of approximately 20% was observed with a small number of adhered cells.
• The sapphire substrate's high transparency is compatible with optical detection methods.

Conclusions:

• Bio-functionalized electrical graphene sensors on sapphire show promise for sensitive cancer cell detection.
• These sensors can potentially monitor cellular electrical behavior and detect circulating tumor cells (CTCs).
• The technology offers compatibility with existing optical detection bioassays.