# Biodegradable copper complexing polymeric microparticles relieve oxidative stress

## TL;DR

A new biodegradable microparticle system is developed to combat oxidative stress by catalytically degrading harmful hydrogen peroxide.

## Contribution

A novel copper-complexing polymeric microparticle platform is introduced for efficient and biocompatible antioxidant therapy.

## Key findings

- Cu-PASmp catalytically degrades hydrogen peroxide and protects cells from oxidative stress.
- Cu-PASmp and PASmp show excellent biocompatibility and no immunogenic response in macrophages.
- The presence of Cu-PASmp reduces the need for cells to express SOD1, indicating lower oxidative stress.

## Abstract

Current antioxidant therapies targeting reactive oxygen species (ROS) are often hindered by limitations in stability, efficacy, dosage tolerance, biocompatibility, or immunogenicity. To address these challenges, we developed a therapeutic platform based on polymer microparticles composed of poly(propanediol-co-(hydroxyphenyl methylene)amino-propanediol sebacate) (PAS), fabricated via a straightforward and scalable co-solvent precipitation method. When chelated with copper(ii) ions, these microparticles (Cu-PASmp) catalytically degrade hydrogen peroxide and protect cells under oxidative stress. Both Cu-PASmp and PASmp demonstrate excellent biocompatibility and elicit no detectable immunogenic response in either M0 or M1 macrophages. Moreover, their presence appears to reduce the need for cells to express superoxide dismutase (SOD1), indicating a decrease in oxidative stress experienced by the cells. Collectively, these results position Cu-PASmp as a promising, catalytic antioxidant platform.

Copper–ligand microparticles act as biocatalytic scavengers of reactive oxygen species, providing cellular protection against oxidative stress and restoring balance to inflammatory responses.