Hybrid polymer composite membrane for an electromagnetic (EM) valveless micropump

Abstract

In this paper, we report on a hybrid membrane used as an actuator in an electromagnetically driven valveless micropump developed using MEMS processes. The membrane structure consists of the combination of a magnetic polymer composite membrane and an attached bulk permanent magnet which is expected to have a compact structure and a strong magnetic force with maintained membrane flexibility. A soft polymeric material made of polydimethylsiloxane (PDMS) is initially mixed with neodymium magnetic particles (NdFeB) to form a magnetic polymer composite membrane. The membrane is then bonded with the PDMS based microfluidic part, developed using soft lithography process. The developed micropump was tested in terms of the actuator membrane deflection capability and the fluidic flow of the injected fluid sample through the microfluidic channel. The experimental results show that the magnetic composite actuator membrane with an attached bulk permanent magnet is capable of producing a maximum membrane deflection of up to 106 µm. The functionality test of the electromagnetic (EM) actuator for fluid pumping purposes was done by supplying an AC voltage with various amplitudes, signal waves and frequencies. A wide range of sample injection rates from a few µl min−1 to tens of nl min−1 was achieved with a maximum flow rate of 6.6 µl min−1. The injection flow rate of the EM micropump can be controlled by adjusting the voltage amplitude and frequency supplied to the EM coil, to control the membrane deflection in the pump chamber. The designed valveless EM micropump has a very high potential to enhance the drug delivery system capability in biomedical applications.

Unidirectional and bidirectional valveless electromagnetic micropump with PDMS-Fe3O4 nanocomposite magnetic membrane

“…The problem of the large size of the micropump also exists in the presented work by Zhou et al [16]. Among the presented works in table 3, the introduced micropump by Said et al [20] is closer to our own work. They used an attached bulk permanent magnet on the magnetic membrane in order to achieve the needed membrane displacement.…”

“…He et al presented an electro magnetic micropump with an operating frequency range of 10-5000 Hz [19]. In 2017, Said et al fabricated an electro magnetic micropump with polydimethylsiloxane (PDMS)-NdFeB composite membrane [20]. In another design, Said et al utilized different composite patterns in order to investigate their effects on the micropump's membrane displacement.…”

Polymer-Based MEMS Electromagnetic Actuator for Biomedical Application: A Review

“…DI water is pumped with maximum flow rate of 319.6 μL/min at a frequency of 36.9 Hz with supply current of 0.18 A. Said et al [118] combined the bulky permanent magnet with magnetic composite membrane to improve the reliability of the membrane and at the same time to increase the magnetic induction. The hybrid structure could produce a magnetic flux density of 37.637 mT enabling a controllable peristaltic pumping of microfluidic sample with a flowrate of 6.6 μL/min.…”

An ultrafast response and precisely controllable soft electromagnet actuator based on Ecoflex rubber film filled with neodymium-iron-boron

“…In contrast, with both thermal and pneumatic abilities, solenoid drive possesses extraordinary performance in response speed and precise control. Therefore, it can meet the requirements of agile, continuous, and dynamic actuation [20][21][22][23]. In this paper, a flexible magnetic actuator (FMA) was fabricated with a flexible magnetic elastomer.…”