Enzymes, Immobilized article 18 chemistry 18 immobilized enzyme 18 Kinetics 16 in vitro study 14 Hydrogen-Ion Concentration 12 Oxidation-Reduction 12 Porphobilinogen Synthase 12 porphobilinogen synthase 12 porphyrin 12 Cattle 10 Electrodes 10 Liver 10 Sepharose 10 cattle 10 electrode 10 enzyme 10 enzymology 10 oxidation reduction reaction 10 Electrochemistry 8 Support, Non-U.S. Gov't 8 animal experiment 8 electrochemistry 8 liver 8 Animal 6 Catalysis 6 Drug Stability 6 Enzymes 6 Porphyrins 6