A Pump-Free, Hydraulic-Amplification Oscillatory Microfluidic Device for Continuous Particle and Cell Manipulation.

Microfluidics can achieve the spatiotemporal manipulation of particles and cells in the microscale fluids, but highly relies on the accuracy of the pumping systems. To overcome this issue, a pump-free, hydraulic-amplification oscillatory microfluidic (PHOMF) device is presented, which can be actuated by fingers to handle particles and cells within the microchannel. The PHOMF device has a hydraulic-amplification module for pressure transfer and a soft microchannel module for the generation of oscillatory flows. This is made possible by the periodic transfer of finger-driven liquid pressure to the soft microchannel. This pressure causes the soft microchannel to deform and then drives the reciprocating flow of fluid volumes within the microchannel. In the oscillatory flow, particles and cells achieve single-line focusing driven by the spatially accumulated inertial and elastic lift forces. The particle elasto-inertial focusing theory in the PHOMF microchannel has been revealed. To demonstrate the system's practicality, the PHOMF device is utilized to achieve the early observation of platelet clots (3 min) and the rapid staining of cancer cells (8 min). The PHOMF device provides a miniaturized, inexpensive, and efficient detection tool for lab-on-a-chip, and has the potential to become a mass-produced, widely available, and convenient disease detection product.