Development of a microfluidic-based assay on a novel nitrocellulose platform

Area of Science:

• Analytical Chemistry
• Biotechnology
• Materials Science

Background:

• Microfluidic paper-based analytical devices (μPADs) offer low-cost, portable platforms for diagnostics.
• Nitrocellulose membranes are widely used in immunoassays but their integration into μPADs for quantitative colorimetric detection requires further development.

Purpose of the Study:

• To develop and characterize a novel microfluidic paper-based analytical device (μPAD) for the colorimetric detection and quantification of IgG antibodies.
• To utilize a nitrocellulose membrane within the μPAD for enhanced assay performance.

Main Methods:

• Fabrication of a μPAD using layered polyethylene terephthalate (PET) and pressure-sensitive adhesives (PSA).
• Immobilization of biotin-labeled Goat Anti-Mouse IgG antibody on a nitrocellulose membrane channel.
• Sequential incubation with wash solutions, streptavidin-alkaline phosphatase (Strep-ALP) conjugate, and para-nitrophenyl phosphate (p-NPP) substrate for colorimetric detection.

Main Results:

• The developed μPAD demonstrated a colorimetric response (yellow color) proportional to the concentration of Strep-ALP.
• Quantitative analysis yielded a linear range of inverse yellow color intensities versus Strep-ALP concentrations.
• The device successfully detected and quantified IgG antibodies through colorimetric analysis.

Conclusions:

• A novel and simple μPAD utilizing a nitrocellulose membrane has been successfully developed for IgG antibody detection.
• This μPAD facilitates colorimetric assays for antibody detection and quantification, showing potential for broader applications.
• The integration of nitrocellulose membranes in μPADs can enhance the utility of colorimetric detection methods.