The 40nm Standard For most lateral flow assays, 40nm gold is the industry standard. It offers the best balance between color intensity (optical density) and steric stability against aggregation. When to Use 20nm? Smaller 20nm particles have a higher surface-area-to-volume ratio, allowing for higher antibody loading density. This can be advantageous for competitive assays where … Read more
Passive Adsorption The traditional method relies on electrostatic and hydrophobic interactions. It is simple and cost-effective but can be unstable with certain antibodies. Covalent Binding (EDC/NHS) For higher stability and reproducibility, covalent coupling using EDC/NHS chemistry is superior. Due Bio recommends optimized conjugation buffers to maximize antibody orientation on the gold nanoparticle surface.
Visual Contrast Colloidal gold (red) is the industry standard for qualitative tests. Latex beads (blue/colored) offer higher visual contrast and potential for multiplexing (different colors for different lines). Compatibility Due Bio Universal Strips are compatible with both labeling systems. Our pore structure is optimized to allow smooth flow of particles up to 400nm in diameter.