Paper-based multiplexed vertical flow assay for point-of-care testing.

Area of Science:

• Biomedical Engineering
• Immunodiagnostics
• Point-of-Care Testing

Background:

• Accurate and rapid disease diagnostics are crucial for effective public health management.
• Current diagnostic methods can be time-consuming and require specialized laboratory equipment.
• There is a need for accessible, multiplexed diagnostic platforms for simultaneous detection of multiple biomarkers.

Purpose of the Study:

• To develop a novel multiplexed point-of-care immunodiagnostic assay (xVFA) for antibody detection in human sera.
• To enable rapid, simultaneous, and quantitative measurement of multiple analytes.
• To validate the assay's performance using Lyme-specific antibodies as a model.

Main Methods:

• Vertical stacking of functional paper layers to create a multiplexed vertical flow assay (xVFA).
• Utilizing gold nanoparticles for colorimetric signal generation upon antigen capture.
• Employing a cost-effective mobile-phone reader for assay imaging and server-based analysis.
• Evaluating assay performance with human sera for Lyme-specific antibody detection.

Main Results:

• The xVFA platform demonstrated a rapid assay completion time of 20 minutes.
• The assay allowed for simultaneous and quantitative measurement of target antibodies.
• The system successfully detected Lyme-specific antibodies in human sera.
• The mobile-phone reader coupled with server analysis provided efficient data interpretation.

Conclusions:

• The developed xVFA is a rapid, simple, and inexpensive point-of-care diagnostic platform.
• The assay enables simultaneous and quantitative detection of multiple antibodies or antigens.
• This technology holds significant potential for disease diagnostics in resource-limited settings.