Tape'n roll inertial microfluidics.

• Inertial regime fluidics for 2D/3D structures: spiral, straight, squarel, helical, and double oriented 3D-spiral channels. • 3D orthogonal double spiral microchannel design to achieve single line inertial focusing. • Versatile and rapid fabrication method for adjustable transformation of any planar layout to 3D geometries. • A computational approach to model particle trajectory in 3D geometries. • A fabrication method that can be adapted by many domains of microfluidics. Particle focusing and separation in microfluidic devices are critical for biological and medical applications. Inertial microfluidics is used for high throughput bio-particle focusing and separation. Most of the inertial microfluidic systems use planar structures for squeezing the particles in streams. Particle manipulation in 3D structures is often overlooked due to the complexity of the fabrication. In this study, we introduce some novel microchannel designs for inertial microfluidics by using a simple fabrication method that allows construction of both 2D and 3D structures. First, inertial migration of particles in 2D layouts including straight, spiral, and square spiral channels is investigated. Afterward, by applying a "tape'n roll" method, helical and double oriented spiral channels are configured and unexplored inertial migration behaviours are observed. Thanks to the simplicity of the fabrication and the unique characteristics of the new designs, high performance microfluidic inertial migration results can be obtained without any need for complicated microfabrication steps. The design optimization cycle can also be shortened using a computational approach we introduce in this study. [ABSTRACT FROM AUTHOR]