Advanced SPR biosensor with optimized gold-TiO2 D-shaped photonic crystal fiber for precise multi-cancer detection.

Area of Science:

• Photonics and Biosensing
• Materials Science and Nanotechnology

Background:

• Surface Plasmon Resonance (SPR) biosensors are crucial for label-free biomolecular detection.
• Photonic Crystal Fibers (PCF) offer unique light-confining properties for enhanced sensing.
• Titanium dioxide (TiO₂) coatings can improve the performance of gold-based SPR sensors.

Purpose of the Study:

• To design, investigate, and optimize an SPR biosensor utilizing a D-shaped PCF.
• To enhance biosensor sensitivity and diagnostic accuracy through material layering and structural optimization.
• To develop a simplified yet high-performance biosensing platform.

Main Methods:

• Fabrication of a D-shaped PCF with gold and TiO₂ layers.
• Optimization of structural parameters for effective light coupling and signal enhancement.
• Performance evaluation using various cancer cell lines and refractive index variations.

Main Results:

• Achieved maximum wavelength sensitivity (WS) of 42,000 nm/RIU.
• Recorded maximum amplitude sensitivity (AS) of -1862.72 RIU.
• Obtained maximum figure of merit (FOM) of 1393.128 RIU⁻¹.
• Demonstrated exceptional diagnostic accuracy across multiple cancer cell types.

Conclusions:

• The optimized D-shaped PCF SPR biosensor offers high sensitivity and precision for detecting minute refractive index changes.
• The TiO₂ layer significantly enhances the sensor's performance.
• This biosensor presents a reliable and accurate platform for biological and chemical sensing applications.