Highly Sensitive Bimetallic-Metal Nitride SPR Biosensor for Urine Glucose Detection

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Urine glucose monitoring is crucial for diabetes management.
• Existing biosensors often lack the required sensitivity and rapid response.
• Metal nitride materials offer potential for enhanced biosensor performance.

Purpose of the Study:

• To develop a highly sensitive bimetallic Surface Plasmon Resonance (SPR) biosensor for efficient urine glucose detection.
• To optimize sensor structure using gold, silver, and aluminum nitride layers.
• To evaluate the sensor's performance for various diabetic patient samples.

Main Methods:

• Fabrication of a five-layer SPR biosensor on a BK-7 prism.
• Optimization of bimetallic (Au-Ag) and metal nitride (AlN) layer thicknesses and sequences.
• Performance evaluation using visible wavelength (λ = 633 nm) and analysis of SPR curves.

Main Results:

• Achieved a significant sensitivity of 411°/RIU and a Figure of Merit (FoM) of 105.38 /RIU.
• Determined optimal layer parameters: Au (25 nm) - Ag (25 nm) - AlN (15 nm).
• Demonstrated a high resolution of 4.17e-06 and rapid response for glucose detection.

Conclusions:

• The proposed bimetallic SPR biosensor with AlN exhibits superior performance for urine glucose detection.
• The sensor's high sensitivity and rapid response show promise for clinical applications in diabetes monitoring.
• The synergistic effect of bimetallic and metal nitride layers enhances sensor efficacy.