Amperometric Monitoring of Dissolution of pH-Responsive EUDRAGIT<sup>®</sup> 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...

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Bibliographic Details
Main Authors: Júlia Mestres, Francesca Leonardi, Klaus Mathwig
Format: Article
Language:English
Published: MDPI AG 2022-02-01
Series:Micromachines
Subjects:
Online Access:https://www.mdpi.com/2072-666X/13/3/362
Description
Summary: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<sup>®</sup> controlled release acrylate copolymers for protecting electrode surfaces. The dissolution of these polymers—namely EUDRAGIT<sup>®</sup> L 30 D-55 and EUDRAGIT<sup>®</sup> 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<sup>®</sup> dissolution profiles. It will find future applications in determining the protection of polymer electrode coating in real matrices and in vivo applications.
ISSN:2072-666X