Funktionsprinzip und Anwendung der Kraftkompensationsmessmethode für miniaturisierte hydrogelbasierte Sensoren
Publikation: Beitrag in Fachzeitschrift › Forschungsartikel › Beigetragen › Begutachtung
Beitragende
Abstract
Chemical sensors that use a stimulus-responsive hydrogel as a transducer offer many advantages. The hydrogels are inexpensive, easy to manufacture and can be designed for a wide variety of measured variables. Sensor setups that convert the stimulus-dependent swelling pressure into an electrical measurement signal can be easily miniaturized and used as a platform for different types of hydrogels. However, the main disadvantages of hydrogel-based sensor principles are creep and long settling times in the minutes to hours range due to tedious diffusion processes and viscoelastic behavior of hydrogels. Force compensation is a measurement method to successfully counteract these two effects by suppressing the time-driving volume phase transition of the hydrogel. However, the actuator required for this prevented miniaturization of sensor setups in previous works. In this work, therefore, a different type of force compensation is shown which allows the many advantages of the force compensation method to be applied to a hydrogel sensor while ensuring small dimensions of the sensor assembly. This is accomplished by incorporating the swell-suppressing actuator directly into the hydrogel transducer. In this way, the swelling pressure compensation occurs in the hydrogel itself. For this purpose, the hydrogel is designed as a bisensitive hydrogel. As a result, the sensor setup is significantly miniaturized and simplified due to the elimination of complex actuator setups. At the same time, a high settling time reduction is achieved compared to the conventional uncompensated measuring method and the previous compensation approaches are surpassed with a minimum settling time of approx. 3 min. Furthermore, a significant reduction of undesired hysteresis characteristics and the possibility to extend the measuring range is shown. The measurement method is demonstrated using the example of a piezoresistive hydrogel sensor and is transferable to other hydrogel-based sensor principles to improve the sensor properties.
Details
| Originalsprache | Deutsch |
|---|---|
| Seiten (von - bis) | 465-477 |
| Seitenumfang | 13 |
| Fachzeitschrift | Technisches Messen |
| Jahrgang | 89 |
| Ausgabenummer | 7-8 |
| Publikationsstatus | Veröffentlicht - 1 Juli 2022 |
| Peer-Review-Status | Ja |
Externe IDs
| ORCID | /0000-0002-7062-9598/work/174430580 |
|---|
Schlagworte
ASJC Scopus Sachgebiete
Schlagwörter
- Chemical sensors, force compensation, force rebalance, hydrogel-based sensors, settling time, smart hydrogels