US Patent 7432298 Fluorescent polymeric materials containing lipid soluble rhodamine dyes

Fluorescent polymeric materials are disclosed comprising a polymer and one or more lipid soluble rhodamine dyes. The materials are especially useful in the preparation of multicolored microparticles, especially multicolored polystyrene microparticle, for use in the multiplexed analysis of a plurality of analytes in a single sample. When excited by a light source, the materials give off a unique emission based on the nature, concentration and ratio of the dyes therein. Methods of preparing and using said materials are also disclosed.