Immobilized Pepsin resin (Pepsin Agarose) is commonly used to create F(ab’)2 fragments from antibodies. By immobilizing pepsin autolysis and protease contamination is essentially eliminated. Immobilized Pepsin gel hydrolyzes protein non-specifically at pH 1.0 to 3.0, with an optimum activity at pH 1.0. Our highly active pepsin is covalently bound to crosslinked 6% beaded agarose resin and its specific activity is > 6,100 units/ml resin (one unit is defined as releasing 0.001 A280 as TCA hydrolyzed/min. at 37°C). ProteoChems Immobilized Pepsin is packaged as a slurry in buffer at pH 4.5 containing 50% glycerol, 100 mM Sodium Acetate, 0.05% NaN₃.Pepsin protease cleaves non-specifically with some preference for tyrosines and phenylalanine (aromatic residues), although it generally does not cleave at alanine, glycine or valine residues. Recommended conditions are pH 1-3, 20°C to 37°C.