Color-dyes polystyrene particles conjugated with recognition molecules as antibodies, antigens, proteins, or other biomacromolecules are available on request. Unmodified polymer spheres are also offered. These polymer particles find extensive applications in a range of flow assays, diagnostic tests, optical and electronic instrument testing, and calibration. https://www.cd-bioparticles.com/products/colored-polystyrene-particles-287.html