A Flexible Bioresorbable Implantable Sensor for Wireless Dynamic Monitoring of H2O2 Enabled by Pt-Decorated MoO3- x Nanozyme.

Abstract

Accurate spatiotemporal tracking of in vivo hydrogen peroxide (H2O2) flux is pivotal for deciphering pathological mechanisms and guiding precision therapeutics of various diseases. While traditional assays offer accuracy and selectivity, they rely on complex sample handling or are built with rigid and permanent materials, leading to limited temporal resolution and/or requiring secondary surgical retrieval of the implants. Herein, a wireless sensing system based on the flexible and bioresorbable electrochemical sensor is reported for continuous dynamic monitoring of H2O2 in vivo. The Pt-decorated MoO3- x nanozyme enables a high-performance H2O2 sensor with a low detection limit (0.26 µm), sustained catalytic stability (80 h), and robust anti-interference characteristics. Density functional theory calculations reveal the catalytic enhancement mechanism of H2O2 decomposition kinetics by the synergistic effect between oxygen vacancies and Pt. The detection capability of the system is demonstrated by monitoring H2O2 levels in vivo during inflammation and intervention. After completing the mission, the sensor can be fully bioresorbed in the body, avoiding secondary surgical removal. This breakthrough technology establishes a personalized paradigm for redox monitoring in precision medicine.