Lateral Flow Immunoassay

i-colloid 40 nm gold nanoparticles produced by IMRA’s pulsed-laser ablation process are stabilized without surfactants or capping agents such as citrate, and conjugates for lateral flow immunoassays can be generated by high-efficiency passive adsorption of antibodies to particle surfaces. The tightly controlled laser-ablation process generates gold colloids that produce consistent lateral flow assay results. Pulsed-laser ablation also enables production of gold-alloy nanoparticles, such as gold-platinum, that can be passively conjugated like gold but have optical signatures distinct from gold due to their shifted surface plasmon resonance. Multicolor, multiplexed lateral flow immunoassays can be performed with combinations of gold and gold-alloy nanoparticles.