title: Diffusion-based extraction of DMSO from a cell suspension in a three stream, vertical microchannel.
abstract: Cells are routinely cryopreserved for investigative and therapeutic applications. The most common cryoprotective agent (CPA), dimethyl sulfoxide (DMSO), is toxic, and must be removed before cells can be used. This study uses a microfluidic device in which three streams flow vertically in parallel through a rectangular channel 500 µm in depth. Two wash streams flow on either side of a DMSO-laden cell stream, allowing DMSO to diffuse into the wash and be removed, and the washed sample to be collected. The ability of the device to extract DMSO from a cell stream was investigated for sample flow rates from 0.5 to 4.0 mL/min (Pe = 1,263-10,100). Recovery of cells from the device was investigated using Jurkat cells (lymphoblasts) in suspensions ranging from 0.5% to 15% cells by volume. Cell recovery was >95% for all conditions investigated, while DMSO removal comparable to a previously developed two-stream device was achieved in either one-quarter the device length, or at four times the flow rate. The high cell recovery is a ~25% improvement over standard cell washing techniques, and high flow rates achieved are uncommon among microfluidic devices, allowing for processing of clinically relevant cell populations.
authors.affiliation: Department of Mechanical Engineering, University of Minnesota, Minneapolis, Minnesota 55455, USA.
authors.forename: Jacob
authors.initials: J
authors.lastname: Hanna
authors.forename: Allison
authors.initials: A
authors.lastname: Hubel
authors.forename: Erin
authors.initials: E
authors.lastname: Lemke
mesh_terms: D002465:Cell Movement / Q000502:physiology; D048429:Cell Size; D015925:Cryopreservation / Q000295:instrumentation / Q000379:methods*; D003451:Cryoprotective Agents / Q000737:chemistry / Q000302:isolation & purification*; D004058:Diffusion; D004121:Dimethyl Sulfoxide / Q000737:chemistry / Q000302:isolation & purification*; D004867:Equipment Design; D006801:Humans; D019169:Jurkat Cells; D046210:Microfluidic Analytical Techniques / Q000295:instrumentation* / Q000379:methods; D008954:Models, Biological
chemical_list: D003451:Cryoprotective Agents; D004121:Dimethyl Sulfoxide