Pharmacological testing involves measurement of binding affinities of the new compounds for the various targets sites, including receptors, transporters and other protein targets. Homogenate binding assays and autoradiographic methods using the Cyclone phosphor imager are used and data is analyzed using various programs such as Optiquant, KELL and Grafit. In vivo imaging, ex vivo imaging and autoradiographic studies are carried out to study neurotransmitter- receptor interactions like dopamine and drug interactions like clozapine. Studies are carried out with various labeled compounds (tritium, carbon-11, fluorine-18, iodine-123, iodine-124, gallium-68 and others).