Dual-mode pH-programmable enzymatic hydrogel system for on-demand glucose generation.

Area of Science:

• Biomaterials Science
• Polymer Chemistry
• Enzyme Engineering

Background:

• Enzyme immobilization in hydrogels is crucial for biocatalysis.
• Controlling enzyme kinetics within soft materials presents challenges.
• Understanding mass transport and reaction coupling is key for advanced hydrogel applications.

Purpose of the Study:

• To develop a supramolecular enzymatic hydrogel system.
• To investigate the interplay between mass transport and enzyme kinetics.
• To demonstrate novel strategies for controlling enzyme activity within hydrogels.

Main Methods:

• Fabrication of a composite hydrogel using starch, chitosan, and alginate.
• Immobilization of amyloglucosidase (AMG) within the hydrogel matrix.
• Implementation of bulk pH switching and electrochemical local pH modulation for enzyme control.

Main Results:

• The hydrogel system exhibited robust mechanical properties and high hydration.
• Bulk pH switching allowed diffusion-limited enzyme activation and glucose release.
• Electrochemical pH modulation provided rapid, localized, and reversible enzyme control, outperforming bulk methods due to reduced diffusion lengths.

Conclusions:

• Supramolecular hydrogel architecture and external pH gradients effectively regulate enzymatic reaction dynamics.
• Electrochemical control offers superior kinetic performance for enzyme-responsive hydrogels.
• This work provides insights into designing advanced soft materials for controlled biocatalysis.