Fabrication of a MRI Standardization Device From Stacking Highly Patterned Thin PDMS Layers

Magnetic resonance imaging (MRI) is a widely used biomedical imaging technology. The MR image is formed by detecting the nuclear magnetization (caused by powerful magnetic fields) of hydrogen atoms in water, which are prevalent in the human body. We present a unique fabrication method of a multilayered Polydimethylsiloxane (PDMS) device that can be used as a physical model for the standardization of Diffusion Tensor MRI machines. The device consisted of 30 stacked, 10 µm thick PDMS patterned layers. Each 10µm layer is stacked by a unique air pressure technique which helps in laying the layers flat on top of each other without any trapped air bubbles or wrinkles. Each layer includes 1000 microchannels that are filled with de-ionized (DI) water—leading to 30,000 parallel microchannels in a 1.5cm × 1.5cm micro-device. Furthermore, having the ability to make thin patterned PDMS layers (that can be stacked) can help in increasing the analytical ability and functionality of PDMS based microfluidic devices and micro-electromechanical systems in general.