The extraction of the urinary coproporphyrin chromogen and the conversion of the chromogen to porphyrin.
D003306:Coproporphyrins; D006801:Humans; D009282:Naphthalenesulfonates; D011166:Porphyrins / Q000378:metabolism*
D003306:Coproporphyrins; D009282:Naphthalenesulfonates; D011166:Porphyrins; C006671:azo rubin S
CHROMOGEN; PORPHYRIN/metabolism