Rhoamine (IPA: /ˈroʊdəmiːn/) is a family of related chemical compounds, fluorone dyes. Examples are Rhodamine 6G and Rhodamine B. They are used as a dye and as a dye laser gain medium. It is often used as a tracer dye within water to determine the rate and direction of flow and transport. Rhodamine dyes fluoresce and can thus be detected easily and inexpensively with instruments called fluorimeters. Rhodamine dyes are used extensively in biotechnology applications such as fluorescence microscopy, flow cytometry and ELISA.