title: A modified procedure for the preparation of insoluble chromogenic substrates for the determination of proteolytic activity.
abstract: New insoluble chromogenic substrates for the determination of proteolytic activity were prepared by cross-linking gelatin with glutaraldehyde in the presence of congo red or nigrosin. The prepared substrates could detect approximately 0.4 microgram of trypsin per ml. The spontaneous leakage of dyes in water solutions was negligible.
mesh_terms: D000814:Aniline Compounds; D004396:Coloring Agents; D003224:Congo Red; D005780:Gelatin; D005976:Glutaral; D006868:Hydrolysis; D007700:Kinetics; D010447:Peptide Hydrolases / Q000378:metabolism*; D013053:Spectrophotometry / Q000379:methods
chemical_list: D000814:Aniline Compounds; D004396:Coloring Agents; D003224:Congo Red; C002712:nigrosin; D005780:Gelatin; D010447:Peptide Hydrolases; D005976:Glutaral