| AVS 59th Annual International Symposium and Exhibition | |
| MEMS and NEMS | Monday Sessions |
| Session MN+AS-MoM |
| Session: | Characterization of Surfaces and Interfaces in MEMS and NEMS |
| Presenter: | L. Engel, Tel Aviv University, Israel |
| Authors: | L. Engel, Tel Aviv University, Israel I. Sokolov, Tel Aviv University, Israel O. Berkh, Tel Aviv University, Israel K. Adesanya, Ghent University, Belgium E. Vanderleyden, Ghent University, Belgium P. Dubruel, Ghent University, Belgium J. Shklovsky, Tel Aviv University, Israel I. Harari, Tel Aviv University, Israel Y. Shacham-Diamand, Tel Aviv University, Israel S. Krylov, Tel Aviv University, Israel |
| Correspondent: | Click to Email |
Due to their unique mechanical and chemical characteristics, stimuli responsive hydrogels have garnered much interest in the field of biomedics. They perform dramatic volume transitions in response to external environmental stimuli such as pH and ionic strength of the solvent, temperature, and electrical field. Their soft elastomeric nature, serves to minimize mechanical and frictional irritation to the tissue bed, suggesting applications in artificial muscles and biomimetics, and their swelling capacity results in high permeabilities for certain drug molecules and metabolites making them ideal materials for drug delivery. Because the swelling rate of a hydrogel is inversely related to its size, MEMS offers a unique opportunity to exploit the capabilities of responsive hydrogels by minimizing actuator response time. While it is known that hydrogels with fixed charge groups deform when subjected to an externally applied electric field inside an electrolyte bath, the exact mechanism responsible for the deformation continues to be debated.
In this work, we have investigated the volume transformation of Pluronic based electroactive hydrogels immersed in a Krebs bathing solution under an applied electric field. The swelling characteristics of the crosslinked hydrogels were investigated and a model based on finite element analysis is proposed. Bias was applied via parallel Pt electodes and the distance between the electrodes was varied as was the ionic concentration and pH of the solution inside the testing tank. The feasibility of using an array of interdigitated electrodes fabricated on a printed circuit board as a means of actuation hydrogel was demonstrated with the goal of downsizing the hydrogel electrical-stimulation system for the creation of MEMS electro-responsive hydrogel actuators.