Immobilization of ω-transaminase by magnetic PVA-Fe₃O₄ nanoparticles

ω-Transaminase (ω-TA) as a kind of important biocatalyst is widely used in preparation of chiral intermediates. In this paper, a magnetic PVA-Fe₃O₄ nanoparticles was prepared and employed on immobilization of ω-TA to reduce the cost, increase reusability and enhance stability. The prepared magnetic PVA-Fe₃O₄ nanoparticles were characterized by transmission electron microscope (TEM), X-ray diffraction (XRD) and vibrating sample magnetometer (VSM). The average size of magnetic PVA-Fe₃O₄ nanoparticles was located between 30-40 nm ω-TA was immobilized onto magnetic PVA-Fe₃O₄ nanoparticles via glutaraldehyde cross-linking, achieving a wider pH range as 6-8 and also a better thermal stability at 60 °C. Meanwhile, the immobilized ω-TA could be successfully reused for 13 times in biotransformation. These results therefore indicated that the immobilized ω-TA with high stability might be readily utilized in industrial purposes.