An ELISA Lab-on-a-Chip (ELISA-LOC)

Area of Science:

• Biomedical Engineering
• Microfluidics
• Analytical Chemistry

Background:

• Lab-on-a-Chip (LOC) systems offer miniaturized platforms for biological assays.
• Rapid prototyping is crucial for developing cost-effective LOC devices.
• Enzyme-Linked Immunosorbent Assay (ELISA) is a widely used diagnostic technique requiring laboratory infrastructure.

Purpose of the Study:

• To develop a miniature 96-well ELISA Lab-on-a-Chip (ELISA-LOC) using Laminated Object Manufacturing (LOM).
• To integrate key ELISA steps, including washing, directly into the microfluidic device.
• To create a cost-effective, power-independent point-of-care diagnostic tool.

Main Methods:

• Fabrication of a six-layer ELISA-LOC using LOM with acrylic and polycarbonate sheets.
• Micromachining of microfluidic features using a CO2 laser.
• Integration of carbon nanotube (CNT) technology for antibody immobilization.
• Utilizing electrochemiluminescence (ECL) detection with a charge-coupled device (CCD) detector.

Main Results:

• Successful fabrication of a miniature 96-well ELISA-LOC device.
• Demonstrated capability for immunological assays in multiple configurations (1x96, 2x48, 4x24 wells).
• Detection of Staphylococcal enterotoxin B (SEB) down to 0.1 ng/ml using a sandwich ELISA assay.
• The system operates without external power, suitable for syringe-based operation.

Conclusions:

• LOM is a viable and affordable method for rapid prototyping of complex microfluidic ELISA-LOC devices.
• The developed ELISA-LOC system offers sensitive detection comparable to conventional ELISA.
• This power-independent, portable system has significant potential for point-of-care diagnostics and global healthcare delivery.