# Ce‐Doped Lignin‐Based Nanozyme with Heat‐Activated Hydrolase Activity

## TL;DR

Scientists created a sustainable nanozyme from lignin and cerium ions that can break down tough bacterial biofilms when heated.

## Contribution

A novel heat-activated hydrolase nanozyme is developed using renewable lignin and Ce ions, offering a sustainable alternative to traditional enzymes.

## Key findings

- Ce-AL nanozyme hydrolyzes phosphate esters and protein amide bonds effectively.
- Hydrolase activity increases 2.03 times at 100°C compared to 40°C due to thermal optimization.
- Ce-AL combats biofilms from both Gram-negative and Gram-positive bacteria.

## Abstract

Nanozymes are powerful alternatives to natural enzymes, yet the sustainable design of hydrolase nanozymes using renewable ligands remains underexplored. Lignin, as an abundant aromatic biopolymer, offers a promising and green ligand for constructing sustainable nanozymes. In this work, a Ce‐doped lignin‐based hydrolase nanozyme (Ce‐AL) is synthesized using Ce ions coordinated with aminated industrial lignin. The resulting Ce‐Nx centered Ce‐AL enable the hydrolysis of phosphate esters and even stable protein amide bonds. Notably, the hydrolase‐like activity of Ce‐AL at 100°C is 2.03 times that at 40°C, attributable to the thermally optimized Ce‐Nx sites within the protective lignin scaffold. The Ce‐AL effectively combats stubborn biofilms formed by Gram‐negative (Escherichia coli) and Gram‐positive (Staphylococcus aureus) bacteria by selectively hydrolyzing key proteinaceous and nucleotide components of the extracellular polymeric substances and bacterial cell walls. This work highlights lignin as a renewable platform for designing advanced, stimuli‐responsive nanozymes.

A novel Ce‐doped lignin‐based hydrolase nanozyme (Ce‐AL) is synthesized using Ce ions coordinated with aminated industrial lignin. The Ce‐AL effectively hydrolyzes phosphate ester bonds and protein amide bonds, maintain high activity at 100°C, and successfully fights bacteria biofilms. This work achieves the valorization of industrial lignin and expands the nanozyme toolbox with a sustainable and heat‐activated hydrolase nanozyme.