Immobilization of lysozyme on poly(N-isopropyl acrylamide)/2-hydroxyethyl methacrylate copolymer core–shell gel beads

Abstract

The immobilization of chicken egg white lysozyme (Lyz) molecules on poly(N-isopropyl acrylamide) gel beads containing 2-hydroxyethyl methacrylate (HEMA) (PGBH) was studied as a function of temperature and HEMA content. Using dynamic and static light scattering measurements, nanometer-sized PGBH particles were shown to exhibit thermo-responsive behavior, and aggregate formation occurred during temperature changes from 25 to 40°C. The radii of PGBH and Lyz-immobilizing PGBH, the amount of immobilized Lyz and the activity of immobilized Lyz depended on both HEMA content and temperature. Moreover, the activity of immobilized Lyz also depended on the molecular size of the substrates, and the Lyz immobilized on PGBH particles with higher HEMA content showed activity toward low molecular weight substrates at 40°C nearly equal to that of native Lyz, which indicates that no conformational change in the Lyz molecule occurred after immobilization. These results demonstrate that changes in the activity of the immobilized Lyz were due to a balance of an increase in the affinity between the substrate and Lyz resulting from concentration effects and the steric hindrance between the substrate and Lyz incorporated into the PGBH aggregates with increasing HEMA content and temperature. Furthermore, these results demonstrate that PGBH is a useful material as an enzyme immobilization carrier.

Responsive hydrogels – structurally and dimensionally optimized smart frameworks for applications in catalysis, micro-system technology and material science

“…Takahashi et al showed that protein adsorption on microgels is also influenced by hydrophobic/hydrophilic interactions as well as by the size of the particles. 60 They prepared core-shell gel beads by emulsion polymerization. The core was formed by PNIPAAm, whereas the shell consisted of a copolymer of NIPAAm and 2-hydroxyethyl methacrylate (HEMA).…”

Mucoadhesive Gel With Immobilized Lysozyme and Quercetin

“…мукоадгезивних полімерів, проте кількість досліджень в галузі створення мукоадгезивних форм лізоциму достатньо обмежена. Так, отримані іммобілізовані препарати лізоциму з застосуванням похідних целю-лози [3]; хітозану [4], високомолекулярних полімерів, активованих силановими реагентами [5], поліаміду [6], желатинового гідрогелю [7], кріогелю полівіні-лового спирту [8] та ін.…”

Microgels formed by enzyme-mediated polymerization in reverse micelles with tunable activity and high stability

“…Water absorption capacity is related to the effective chain length of the polymer, which can in turn decrease with crosslinker density. 12 In addition, the reaction conversion was found to gradually increase from 27% to 62% when the concentration of MBA increased from 0.15 wt% to 0.90 wt%. The optimal concentration of MBA can be further determined by optical and SEM images of the nal microgels, as shown in Fig.…”