title: Modification of an assay for trypsin and its application for the estimation of enteropeptidase.
abstract: A sensitive method for the estimation of trypsin and enteropeptidase is described. The use of alpha-N-benzoyl-DL-arginine-p-nitroanilide as substrate in combination with the Bratton-Marshall reaction increased the sensitivity of an established method to a degree which permits the determination of enteropeptidase at considerably lower activity levels than heretofore such as those expected in brush border membrane preparations from peroral biopsies of human small intestine.
mesh_terms: D000813:Anilides; D001593:Benzyl Compounds; D010450:Endopeptidases / Q000032:analysis*; D004765:Enteropeptidase / Q000032:analysis*; D005069:Evaluation Studies as Topic; D006801:Humans; D007700:Kinetics; D008722:Methods; D008832:Microchemistry; D009574:Nitro Compounds; D014357:Trypsin / Q000032:analysis*
chemical_list: D000813:Anilides; D001593:Benzyl Compounds; D009574:Nitro Compounds; D010450:Endopeptidases; D014357:Trypsin; D004765:Enteropeptidase