Amperometric Monitoring of Dissolution of pH-Responsive EUDRAGIT(R) Polymer Film Coatings

Electrochemical sensors are powerful tools for the detection and real-time monitoring of a wide variety of analytes. However, the long-term operation of Faradaic sensors in complex media is challenging due to fouling. The protection of the electrode surface during in vivo operation is a key element for improving the monitoring of analytes. Here, we study different EUDRAGIT(R) controlled release acrylate copolymers for protecting electrode surfaces. The dissolution of these polymers-namely EUDRAGIT(R) L 30 D-55 and EUDRAGIT(R) FS 30 D-is triggered by a change in pH of the environment, and it is electrochemically monitored by detecting electrode access by means of a redox probe. The full dissolution of the polymer is achieved within 30 min and the electrode response indicates a complete recovery of the original electrochemical performance. We demonstrate that amperometric sensing is a practical and straightforward technique for real-time and in situ sensing of EUDRAGIT(R) dissolution profiles. It will find future applications in determining the protection of polymer electrode coating in real matrices and in vivo applications.

Automated summary

Electrochemical sensors are powerful tools for detecting and monitoring analytes in real-time. This study focuses on the protective effects of different EUDRAGIT(R) controlled release acrylate copolymers on electrode surfaces. The results demonstrate that amperometric sensing is a practical and straightforward technique for real-time monitoring of EUDRAGIT(R) dissolution profiles.