Protein-Based Anchoring Methods for Nucleic Acid Detection in Lateral Flow Format Assays.

Area of Science:

• Biotechnology
• Biosensors
• Nucleic Acid Detection

Background:

• Lateral flow assays (LFAs) are vital for diagnostics, environmental monitoring, and food safety.
• High-sensitivity nucleic acid detection requires high-density capture surfaces.
• Protein anchors, like streptavidin, are used but lack systematic characterization for nucleic acid LFAs.

Purpose of the Study:

• To systematically characterize protein anchors for nucleic acid detection on nitrocellulose substrates.
• To evaluate anchor robustness, nucleic acid density, and capture efficiency.
• To demonstrate signal enhancement and high-sensitivity detection via increased capture nucleic acid density.

Main Methods:

• Characterization of protein anchors (e.g., streptavidin) on nitrocellulose membranes.
• Quantification of nucleic acid capture density and binding efficiency.
• Optimization of capture surface density through multiple protein loading steps.
• Demonstration of a lateral flow assay for SARS-CoV-2 detection.

Main Results:

• Systematic characterization of protein anchor performance on nitrocellulose.
• Demonstrated signal gains by increasing capture nucleic acid density.
• Achieved high-sensitivity nucleic acid detection with a limit of detection (LOD) of approximately 0.2 nM for a SARS-CoV-2 sequence.

Conclusions:

• Optimized protein anchor strategies enable high-density capture surfaces for nucleic acid detection.
• Increased capture nucleic acid density significantly enhances signal in lateral flow assays.
• Developed high-sensitivity lateral flow assay platform applicable to various nucleic acid targets.