a three-step procedure has been investigated to extract 3,4-dihydroxyphenylalanine ( dopa ) , 3,4-dihydroxyphenylacetic acid ( dopac ) , epinephrine ( e ) , norepinephrine ( ne ) and dopamine ( da ) from a single urinary sample with the object of obtaining extracts pure enough for specific fluorimetric assay .
C0014563
epinephrine
C0028351
norepinephrine