Micro-nanoparticles magnetic trap: Toward high sensitivity and rapid microfluidic continuous flow enzyme immunoassay
Pablo E Guevara-Pantoja1, Margarita Sánchez-Domínguez2, Gabriel A Caballero-Robledo1
1Cinvestav-Monterrey, 66600 Apodaca, Nuevo León, Mexico.
Biomicrofluidics
|February 11, 2020
Summary
This study presents a novel microfluidic immunoassay system for rapid and sensitive detection of antibiotin antibodies. The system achieves femtomolar detection limits in just 40 minutes, ideal for point-of-care diagnostics.
Area of Science:
- Biomedical Engineering
- Analytical Chemistry
- Microfluidics
Background:
- Immunoassays are crucial for disease diagnosis but often require complex procedures and long assay times.
- Microfluidic systems offer miniaturization and automation potential for enhanced immunoassay performance.
- Minimizing nonspecific binding and maximizing analyte capture are key challenges in developing sensitive immunoassays.
Purpose of the Study:
- To develop an integrated microfluidic system for rapid and highly sensitive immunoassays.
- To optimize surface functionalization for reduced nonspecific interactions and improved analyte capture.
- To achieve femtomolar detection limits for antibiotin antibody detection within a short assay time.
Main Methods:
- Development of a microfluidic system incorporating magnetic nanoparticles as immunosupport and a magnetic trap.
- Functionalization of magnetic nanoparticles with silica-polyethylene glycol (PEG) shells to prevent corrosion and nonspecific protein binding.
- One-step surface coating of acrylic microchannels with PEG-functionalized silane to further minimize nonspecific binding.
- Integration of a fluorogenic substrate for continuous flow detection using a fluorescence microscope.
Main Results:
- Achieved a detection limit in the order of femtomolar for antibiotin antibody detection.
- Completed the entire immunoassay process within a total assay time of 40 minutes.
- Quantified a detection limit of 8 pg/mL for antibiotin antibody using a calibration curve.
- Demonstrated successful immobilization and concentration of nanoparticles using a microfluidic magnetic trap.
Conclusions:
- The developed microfluidic immunoassay system offers high sensitivity and rapid detection capabilities.
- The optimized surface functionalization effectively minimizes nonspecific binding, enhancing assay performance.
- The system's simplicity, use of acrylic material, and potential for mass production make it suitable for Point-of-Care applications.
