Bicisate
Bicisate, also known as ethyl cysteinate dimer (ECD), is a N,N'-1,2-ethylene-di-yl-bis-L-cysteinate diethyl ester. It is used in conjunction with technetium Tc99m as a tracer to measure cerebral blood flow with single-photon emission computed tomography (SPECT). The complex of bicisate and technetium Tc99m as a kit was developed by Lantheus Medcl and FDA-approved on November 23, 1994.