Going full circle: dynamic covalent enzyme immobilisation via visually trackable boronate esters.

Area of Science:

• Biocatalysis
• Materials Science
• Chemical Engineering

Background:

• Enzyme immobilization on solid supports allows for biocatalyst reuse but often leads to waste from single-use resins.
• Current methods lack efficient strategies for enzyme removal and support regeneration, contributing to environmental concerns.

Purpose of the Study:

• To develop a reversible enzyme immobilization strategy using boronate ester formation.
• To create a method for easy enzyme release and support regeneration, reducing waste in biocatalysis.

Main Methods:

• Enzymes were functionalized with alizarin-methyliminodiacetic acid (alizarin-IDA).
• Boronate ester linkages were formed between alizarin-IDA enzymes and boronic acid-modified supports.
• A pH-triggered acidic treatment was used for enzyme release and support regeneration.

Main Results:

• A universal labeling protocol was developed for diverse enzymes, retaining 77-95% of native activity.
• Immobilization yields exceeded 90% on various supports, with enzymes demonstrating extensive reusability.
• The load-use-cleave sequence was repeated five times, enabling over 50 catalytic cycles per support without performance loss.

Conclusions:

• The developed reversible immobilization strategy significantly enhances the sustainability of biocatalysis by enabling enzyme recycling and support regeneration.
• Alizarin-IDA acts as a dual-function handle for binding and visual reporting, simplifying process monitoring.
• This method offers a waste-reducing alternative to traditional single-use immobilization resins.