Permeability studies on horse liver alcohol dehydrogenase (HLAD) in polyacrylamide gel beads

Abstract

Abstract Polyacrylamide gel beads with monomer concentrations ranging from 5 to 30% and with constant degree of cross‐linking (5%) were prepared. Dried beads were swollen in buffered HLAD/NAD + solutions and placed in a water‐immiscible organic solution of substrates. Increased enzymatic activity was observed in beads with higher polymer density. Evidence is given that catalyst in the high‐density polymer is concentrated in the outer part of the beads, but is homogeneously distributed in low‐density polymers. This was clearly visualised by high‐resolution NMR imaging on gel beads impregnated with Gd‐DTPA‐labeled HLAD. Furthermore, reaction rates were higher for larger beads.