Immobilization of lipase onto functional cyclomatrix polyphosphazene microspheres

Functional polyphosphazene cyclomatrix microspheres (PMS) containing glucose and dodecyl moieties were utilized for physical adsorption of lipase. In this regard, Candia Rugosa lipase was immobilized onto the above microspheres through physical adsorption, which exhibited catalytic hydrolysis of glycerol triacetate as the model reaction. As observed under transmission electron microscope (TEM) and scanning electron microscope (SEM), the size of all the microspheres ranged from 400 nm to 1 mu m with a mean diameter of 680 nm. Zeta potential analysis demonstrated that the microspheres were negatively charged. The influences of buffer pH, substrate concentration and temperature were also studied along with reusability. The obtained results demonstrated that the immobilized lipase on deprotected glycosylated PMS (D-GPMS) showed the best performance and possessed the highest enzymatic loading activity around 1.0884 mmol L-1 min(-1) g(-1), and retained nearly 50% of its initial activity even after 10 cycles of application. Moreover, the lipase-microsphere complex displayed high pH adaptability from 7 to 9 and temperature stability above 40 degrees C. From the viewpoint of biocompatible PMS support, the GPMS-lipase conjugate have potential applications in field such as food, medicine and environment. (C) 2016 Elsevier B.V. All rights reserved.