Kynurenine is synthesized by the enzyme tryptophan dioxygenase, which is made primarily but not exclusively in the liver.

Bromophenol blue is an acid phthalein dye. Bromophenol blue is used as a tracking dye for electrophoresis.

Morphiceptin is a potent and specific agonist for morphine (μ) receptors. Morphiceptin, as a synthetic peptide, is the amide of a fragment of the milk protein β-casein. Morphiceptin has morphinelike activities and is highly specific for morphine (μ) receptors but not for enkephalin receptors.