Electricity-free hand-held inertial microfluidic sorter for size-based cell sorting

Abstract

Conventional batch-top cell sorters are often bulky and expensive, and miniaturized microfluidic sorters available mostly require field generators and electricity-powered pumping systems. Therefore, the development of a low-cost, portable cell sorter that can be used in low resource settings is essential. In this study, we propose such an electricity-free hand-held inertial microfluidic sorter that can be used for the high-efficiency sorting of differently sized cells in a continuous and passive manner. The proposed hand-held sorter is composed of a wheel-shaped all-in-one syringe inertial microfluidic sorter (i-sorter) with flow stabilizer units and two spring-driven mechanical syringe drivers. The release of the compression spring in the mechanical syringe driver through a one-click operation provides the flow driving force. Passive flow stabilizer units in the i-sorter enable flow-rate-sensitive inertial cell separation for the unstable driving flow rate generated by the low-cost mechanical syringe driver. We successfully achieved sorting of differently sized particles and high-efficiency separation of rare tumor cells from the blood using the fabricated prototype. Our hand-held inertial microfluidic cell sorter has many advantages, including low device cost, simple electricity-free operation, compactness, and portability; additionally, samples do not need to be pre-labelled. Therefore, it has potential for use in low-resource settings.

Keywords: Cell separation; Electricity-free; Hand-held; Inertial microfluidics; Low-resource setting.