Rhodamine B highly fluorescent dye.

Rhodamine   used as a tracer dye within water to determine the rate and direction of flow and transport.

Rhodamine B used extensively in biotechnology applications such as fluorescence microscopy, flow cytometry, fluorescence correlation spectroscopy and ELISA.

Rhodamine B is used in biology as a staining fluorescent dye, sometimes in combination with auramine O, as the auramine-rhodamine stain to demonstrate acid-fast organisms.

Rhodamine B is tunable around 610 nm when used as a laser dye.