Enzymes have great application prospects in environmental monitoring and catalysis because they are highly specific and sensitive. However, maintaining the activity and stability of free enzymes for a long time is a huge problem. One method to overcome these problems is the immobilization of enzymes onto carriers. Our previous work proposed immobilizing enzymes onto core–shell nanoparticles, which have suitable polymer brushes and can obtain high immobilization yields while maintaining enzyme activity. However, non-conductive polymers and nanoparticle carriers limit the possibility of further applications of enzymes, such as sensors or wearable electronic devices. In this contribution, we aim to construct conductive hybrid particle systems by introducing conductive nanoparticles while loading enzymes and studying the activity of the enzyme at this condition.

We designed two strategies: 1. Fixed metal nanoparticles on the surface of silica particles combined with grafted polymers to immobilize enzymes. 2. Fixed metal particles on the grafted polymer brushes for enzyme immobilization. We also control the thickness of the polymer brushes to find the most suitable system for carrying enzymes by adjusting the polymerization time. Our study provides a better understanding of the positioning of conductive components in hybrid particles and opens the door to novel particle-based inks for the printing of enzymatic biosensors.