Preparation and Property of Urease Immobilization with Cationic Poly(4-vinylpyridine) Functionalized Colloidal Particles

J. Zhou, J. Cao, W. Huang, L. Huang, Y. Wang, S. Zhang, Y. Yuan and D. Huaa

Abstract
We report here a novel immobilization matrix for high enzyme loading using cationic hairy latex particles. Specifically, poly(4-vinyl-N-ethylpyridine bromide)-functionalized polymeric colloidal particle was used to immobilize urease by its long charged chain structure. The successful immobilization of urease on the cationic hairy colloidal particles was confirmed by Field-emitting scanning electron microscopy (SEM) images, Fourier transform infrared (FT-IR) spectra and zeta potential measurements. Under the optimized conditions of pH = 8.0 and 1.4 mg mL–1 of urease concentration, the enzyme loading could reach 355 ± 22 mg g–1 support with the activity of 1.486 × 104 ± 169 U g–1 support. The pH and thermal stability of urease was enhanced upon immobilization, and it could retain almost 100 % of its initial activity after repeating the catalysis reaction 10 times. The cationic hairy colloidal particles had not only high protein loading, but also enhanced the stability of enzyme. These properties prompt this type of cationic hairy colloidal particles to be used as a promising matrix for enzyme immobilization.

This work is licensed under a Creative Commons Attribution 4.0 International License

Keywords
urease, poly(4-vinylpyridine), colloidal particles, immobilization