Rhodamine B is an organic chloride salt having N-[9-(2-carboxyphenyl)-6-(diethylamino)-3H-xanthen-3-ylidene]-N-ethylethanaminium as the counterion. An amphoteric dye commonly used as a fluorochrome. It has a role as a fluorescent probe, a fluorochrome and a histological dye. It is an organic chloride salt and a xanthene dye. It contains a rhodamine B(1+). Rhodamine B is used as a tracer dye in water to determine the rate and direction of flow and transport. It is a staining fluorescent dye used in fluorescence microscopy, flow cytometry, fluorescence correlation spectroscopy and ELISA in biotechnology fields.