Design, Fabrication and Characterization of a Microfluidic Device for Ultrasound-based Cell Sorting

Abstract

The isolation and sorting of cells is an important process in research and hospital laboratories. Most research laboratories incorporate fluorescently or magnetically labeled antibodies adherent to cell surface antigens for cell identification and separation. MiCS (Microbubble Cell Sorting) is a new technique that overcomes the limitations of existing cell sorting techniques by using ultrasound traveling waves and microbubble tags. A microfluidic device consisting of a flow channel was developed for effectively performing MiCS. The device was designed with the aim of obtaining traveling waves in the flow channel by using various design considerations and Finite Element Analysis (FEA) simulations. Placing the flow channel in the acoustic far-field provided the necessary traveling-wave regime. Subsequently, the device was fabricated by employing manufacturing processes like laser cutting, micromachining, and acrylic bonding. The device was then characterized by performing electrical impedance analysis, flow continuity experiments, and pulse-echo testing. Results suggested that flow in the flow channel was continuous, and the transducer operated effectively.