# Hierarchical inverse opal hydrogel coatings for superhydrophobic, antibacterial, and drug-responsive catheter interfaces

## TL;DR

A new coating for catheters prevents infections and biofouling by combining superhydrophobic properties, antibacterial effects, and drug responsiveness.

## Contribution

A hierarchical inverse opal hydrogel coating is introduced with tunable wettability, antibacterial efficiency, and structural-color feedback.

## Key findings

- The coating achieved 98.9% antibacterial efficiency against E. coli.
- It demonstrated stress-responsive wetting transitions and structural-color visual monitoring.
- The material showed excellent hemocompatibility, cytocompatibility, and in vivo biosafety.

## Abstract

Catheter-related infections and biofouling remain critical challenges in clinical practice due to limited surface functionalities and rapid bacterial biofilm formation.

We developed a universal bottom-up strategy to fabricate hierarchical inverse opal hydrogel coatings on medical catheters via dopamine-mediated substrate activation, dual-layer colloidal assembly, and polymer infiltration, followed by oil infusion to enable adaptive wettability and low-friction liquid mobility.

The coatings exhibited stress-responsive wetting transitions, structural-color-enabled visual monitoring of degradation, and tunable droplet adhesion by modulating pore geometry. In vitro tests showed 98.9% antibacterial efficiency against E. coli, together with excellent hemocompatibility, cytocompatibility, and in vivo biosafety.

By integrating passive antifouling, controlled drug release, and real-time structural feedback in a single interface, this platform provides a robust route toward infection-resistant and intelligent catheter devices.