A disposable bio-nano-chip using agarose beads for high performance immunoassays

Area of Science:

• Biomedical Engineering
• Materials Science
• Analytical Chemistry

Background:

• Immunoassays require sensitive and cost-effective detection platforms.
• Microfluidic devices offer advantages in sample handling and assay miniaturization.
• Existing bio-nano-chip technologies face challenges in cost and fabrication complexity.

Purpose of the Study:

• To fabricate a novel, disposable bio-nano-chip (BNC) for high-performance immunoassays.
• To develop a cost-effective microfluidic device using polydimethylsiloxane (PDMS) and thiolene-based optical epoxy.
• To characterize the performance of the BNC for C-reactive protein (CRP) detection.

Main Methods:

• Fabrication of a microfluidic device using PDMS and thiolene-based optical epoxy.
• A novel room temperature (RT) bonding technique for irreversible covalent bonding.
• Integration of agarose bead sensors sensitized with anti-CRP antibody.
• Fluorescent sandwich-type immunoassay for performance characterization.
• Computational fluid dynamics (CFD) for modeling analyte penetration.

Main Results:

• Successful fabrication of a disposable BNC with integrated agarose bead sensors.
• Demonstrated analyte penetration into agarose beads correlating with CFD simulations.
• Established a linear dynamic range of 1 ng/mL to 50 ng/mL for CRP detection.
• Achieved a limit of detection less than 1 ng/mL.

Conclusions:

• The developed disposable BNC is a cost-effective and high-performance platform for immunoassays.
• The novel RT bonding technique is compatible with sensor integration and microfluidic fabrication.
• The BNC demonstrates excellent sensitivity and accuracy for CRP detection, suitable for diagnostic applications.