Instrument-Free Quantitative Detection of Analytes Using a Combo Lateral Flow Assay

Area of Science:

• Biotechnology
• Assay Development
• Point-of-Care Diagnostics

Background:

• Lateral flow assays (LFAs) are cost-effective, rapid point-of-care (PoC) diagnostic tools.
• Conventional LFAs are typically qualitative and suffer from limitations like narrow dynamic ranges and the Hook Effect.

Purpose of the Study:

• To develop a quantitative lateral flow assay (CLFA) that overcomes the limitations of traditional LFAs.
• To enable instrument-free, quantitative detection of analytes across a broad concentration range.

Main Methods:

• Integration of both sandwich and competitive assay formats into a single combo lateral flow assay (CLFA).
• Development of AI-based image analysis using a smartphone app to enhance measurement precision.
• Minimal modification to standard LFA design by adding one extra test line.

Main Results:

• The CLFA enables quantitative detection of analytes without external instruments.
• CLFA demonstrates a broad dynamic range and is not susceptible to the Hook Effect.
• AI-enhanced analysis improves the precision of CLFA measurements.

Conclusions:

• CLFA offers a cost-effective and simple method for quantitative diagnostics.
• The technology overcomes key limitations of conventional LFAs, enhancing their utility.
• CLFA is expected to find widespread applications in diagnostics and research.