ELISA-LOC: lab-on-a-chip for enzyme-linked immunodetection

Area of Science:

• Biotechnology
• Biosensor Technology
• Microfluidics

Background:

• Conventional immunoassays require laboratory settings and specialized equipment.
• Point-of-care diagnostics are crucial for rapid disease detection and management.
• Detection of foodborne pathogens like Staphylococcal Enterotoxin B (SEB) is critical for public health.

Purpose of the Study:

• To design, fabricate, and test a miniature 96-well ELISA lab-on-a-chip (ELISA-LOC) for immunological detection of SEB.
• To develop a portable, lab-free system for immunological assays.
• To integrate microfluidics, carbon nanotube technology, electrochemiluminescence, and CCD detection for enhanced sensitivity.

Main Methods:

• Fabrication of the ELISA-LOC using Laminated Object Manufacturing (LOM) with acrylic and polycarbonate layers.
• Integration of microfluidics with surface tension valves for reagent delivery and removal.
• Utilization of carbon nanotube (CNT) technology for antibody immobilization.
• Implementation of electrochemiluminescence (ECL) detection coupled with a charge-coupled device (CCD) detector.

Main Results:

• The ELISA-LOC successfully detected Staphylococcal Enterotoxin B (SEB) using a sandwich ELISA assay.
• Achieved a limit of detection as low as 0.1 ng/mL for SEB, comparable to conventional ELISA.
• Demonstrated a power-free, syringe-operated fluidics system for simplified assay execution.
• The system allows immunological assays to be performed outside of a traditional laboratory environment.

Conclusions:

• The developed ELISA-LOC is a viable point-of-care (POC) system for sensitive and rapid immunological detection of SEB.
• This technology offers a simplified approach to complex medical assays, eliminating the need for laboratory infrastructure.
• The integrated biosensing elements and microfluidics pave the way for broader applications in diagnostics.