Influence of Bacterial Cellulose Gel Film Modification on Its Mechanical Properties and Ability to Covalently Bind Enzymes

The rules for modifying the gel film of bacterial cellulose without disturbing its film structure are optimized. Using FTIR spectroscopy and titration, it is shown that oxidation with sodium periodate makes it possible to obtain dialdehyde derivatives of gel films with different amounts of aldehyde groups. The conditions for immobilizing pepsin and β-galactosidase enzymes on modified gel films are selected. An analysis of IR spectra shows that the enzymes are retained on the gel film owing to formation of azomethine bonds between the amino groups of the protein and the aldehyde groups of the film. The efficiency of immobilization depends on the type of enzyme and the conditions of the grafting reaction; under the same conditions, the gel film binds more β-galactosidase than pepsin.