Antigen detection based on background fluorescence quenching immunochromatographic assay

Area of Science:

• Biomedical Engineering
• Analytical Chemistry
• Immunotechnology

Background:

• Traditional Gold Immunochromatographic Assays (GICA) are primarily qualitative.
• There is a need for fast, simple, and quantitative GICA methods in medicine.

Purpose of the Study:

• To establish a novel, quantitative GICA named background fluorescence quenching immunochromatographic assay (bFQICA).
• To assess the performance of bFQICA using alpha-fetoprotein (AFP) as a model analyte.

Main Methods:

• Development of bFQICA utilizing fluorescence quenching and nitrocellulose membrane background signals.
• Establishment of standard curves for AFP concentration using serial dilutions.
• Evaluation of assay variability, sensitivity, and long-term stability.

Main Results:

• bFQICA successfully established standard curves for AFP quantification.
• The assay demonstrated low variability (CV 10.4-15.2%) and high sensitivity (detecting AFP at 1ngmL(-1)).
• Results showed excellent correlation (r=0.98) with a commercial electrochemiluminescence immunoassay.

Conclusions:

• bFQICA offers accurate measurements via a unique fluorescence ratio (F1/F2).
• The assay provides both qualitative and quantitative capabilities with high sensitivity.
• bFQICA shows promise for broad applications in disease investigation and diagnostics.