Cancer Cell Detection on the Surface of Top-Gated Monolayer Graphene via Raman Spectroscopy

Area of Science:

• Nanotechnology
• Biomedical Engineering
• Spectroscopy

Background:

• Label-free biosensors are crucial for sensitive and rapid disease detection.
• Graphene's unique electronic and optical properties offer potential for advanced biosensing applications.
• Cancer cell detection remains a significant challenge in early diagnosis and treatment.

Purpose of the Study:

• To develop a label-free biosensor utilizing monolayer graphene's Raman spectroscopic signatures for cancer cell detection.
• To investigate the influence of cancer cells on graphene's Raman spectra via electron-phonon coupling.
• To establish a correlation between cancer cell presence and specific Raman vibrational modes.

Main Methods:

• Utilizing electrostatically gated monolayer graphene on SiO2/Si substrates.
• Analyzing Raman spectra in the presence and absence of cancer cells across a voltage range (0-5 V).
• Employing Density Functional Theory (DFT) simulations to correlate cancer cells with observed spectral changes.

Main Results:

• Observed modifications in graphene's G and 2D Raman modes due to cancer cell interaction.
• Identified C-H and N-H bonds of phenylalanine as key indicators for biosensing activity.
• Demonstrated successful cancer cell detection without prior cell culturing.

Conclusions:

• Monolayer graphene's Raman spectra are sensitive to the presence of cancer cells through electron-phonon coupling.
• The developed biosensor offers a label-free, efficient method for cancer cell detection.
• This approach holds promise for simplified and rapid diagnostic tools in oncology.