Novel thin polymeric magnetic membranes study for applications in the future biomedical devices

Abstract

Biomedical devices such as pumping/mixing fluids, cell-culturing, and drug delivery often use different actuation methods. Magnetic actuation using magnetic particles that are embedded in thin flexible polymeric sheets (membranes) is convenient to use, especially for medical implantable devices such as micropumps, due to the fact they do not require board batteries and exhibit better performances than other actuation methods. The fabrication process of these membranes uses a random distribution of particles. In this work, membranes with a local distribution of magnetic particles are investigated and compared to membranes with randomly distributed magnetic particles, which in turn may enhance the actuation performance for certain applications. Iron oxide particles are embedded into polydimethylsiloxane, and micromagnets are used to localize the position of the magnetic particles within the polymeric mixture during the fabrication process. Three different concentrations are investigated: low (7.5 w/v%), medium (10 w/v%), and high (12.5 w/v%). Static and dynamic measurements of membrane’s maximum deflection values are compared for both types of membranes with a random and a local distribution of magnetic particles. The maximum deflection location is shifted due to the presence of the localized magnetic field for a membrane with a local distribution of magnetic particles. From the experimental results, it is evident that the deflection performance result is much higher for the local distribution of the magnetic particles’ membrane during a static magnetic load and slightly lower during a dynamic (sinewave input) magnetic load at frequencies of 1 and 5 Hz.