Agarose-gel coating for improving the polydopamine-based pH sensor stability in continuous pH measurements†

Abstract

Continuous monitoring in healthcare could transform patient care by improving patient outcomes and reducing costs through rapid detection and timely intervention. The pH of body fluids is an essential indicator for detecting acid/base imbalances and subsequent diseases, as well as monitoring organ functions. However, current pH sensors experience signal drifts over continuous measurements, inhibiting their ability to provide longitudinal body's pH status. To enable real-time, continuous pH monitoring, we developed a polydopamine (PDA)-based pH sensor and validated its performance in PBS and simulated wound fluid exudate (WFE). To increase signal stability for continuous performance, heat treatment and agarose gel coating were applied to the sensor, and we observed that the agarose coating greatly improved the signal drift.