An optical pickup enzyme-linked immunosorbent assay (ELISA) with a microfluidic disk

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Immunotechnology

Background:

• Conventional enzyme-linked immunosorbent assay (ELISA) often requires multiple steps and can be time-consuming.
• Microfluidic platforms offer potential for faster and more sensitive immunoassays.
• Optical detection methods can provide sensitive and label-free or minimally labeled detection.

Purpose of the Study:

• To develop and evaluate a novel optical pickup enzyme-linked immunosorbent assay (ELISA) using a custom-designed microfluidic disk.
• To assess the performance of this new platform for the rapid detection of C-reactive protein (CRP).
• To compare the sensitivity and speed of the microfluidic ELISA with conventional microplate-based ELISA.

Main Methods:

• Fabrication of an acrylic microfluidic disk with eight radially arranged channels using CO2 laser machining.
• Immobilization of capture antibodies within the microfluidic channels.
• Detection of enzyme-catalyzed nanoaggregation of o-phenylenediamine via laser reflectivity changes after immunoreaction.
• Assay development for C-reactive protein (CRP) detection.

Main Results:

• Successful implementation of optical pickup ELISA on the microfluidic disk.
• Rapid CRP assay completion in approximately 20 minutes.
• Achieved a limit of detection of 2 ng/mL for CRP, demonstrating higher sensitivity than conventional ELISA.

Conclusions:

• The developed optical pickup ELISA on a microfluidic disk is a rapid and highly sensitive method for CRP detection.
• This platform offers advantages over traditional ELISA in terms of speed and sensitivity.
• The microfluidic disk design facilitates semi-automatic sample handling and washing, improving assay efficiency.