All-Optical Planar Polymer Waveguide-Based Biosensor Chip Designed for Smartphone-Assisted Detection of Vitamin D.

Area of Science:

• Optoelectronics
• Nanotechnology
• Biomedical Engineering

Background:

• Plasmonic sensors offer high sensitivity for biomolecule detection.
• Smartphone integration enables portable and accessible diagnostic tools.
• Accurate measurement of 25-hydroxyvitamin D (25OHD) is crucial for health assessment.

Purpose of the Study:

• To report a novel all-optical plasmonic sensor platform integrated into a smartphone.
• To demonstrate the platform's capability for detecting 25-hydroxyvitamin D (25OHD) in human serum.
• To showcase the potential for miniaturized, cost-efficient, and parallelized biosensing.

Main Methods:

• Development of a polymer chip-based planar-optical waveguide structure.
• Utilisation of an aptamer-based assay enhanced with gold nanoparticles (AuNPs).
• Detection of 25-hydroxyvitamin D (25OHD) using the integrated smartphone sensor system.

Main Results:

• Achieved a sensitivity of 0.752 pixel/nM for 25-hydroxyvitamin D (25OHD) detection.
• Demonstrated detection of 25OHD in human serum samples within a 0-100 nM concentration range.
• Confirmed the potential for miniaturization, parallelization, and cost-efficient fabrication.

Conclusions:

• The developed all-optical plasmonic sensor platform is suitable for smartphone integration.
• The sensor system shows promise for sensitive and specific detection of biomarkers like 25OHD.
• This technology has significant potential for widespread lab-on-chip applications and point-of-care diagnostics.