Enzyme crystal embedded in latex film as immobilized enzyme

Summary A simple and effective method for enzyme crystals immobilization is developed. The water- based acrylic latex mixed with enzyme crystals is coated on a porous membrane. When dried, the latex produces a continuous and strong film in which enzyme crystals are embedded. Latex of three different compositions are synthesized to immobilize urease. The urease crystals embedded in latex film shows a good thermal stability that the activity remains at 60% of its initial activity after 5 days' incubation at 50°C. The film containing amorphous urease powder, on the other hand, has a very poor thermal stability that urease activity decreases to 50% and 3% of its initial activity after 8 hrs' and 3 days' incubation, respectively. The diffusion limitation in the lattices of urease crystal is the main reason for the low activity retention of urease crystals embedded in the latex film.