Fig. 7

A microfluidic system for dissociation of CNS into viable neurons. a Schematic drawing of the microdevice, top-down view, with central portion magnified and shown in oblique lateral view. Tissue dissociation takes place in the narrow central orifice. Length (L), width (W), and height (H) were varied during optimization. b Photograph of single-channel microfluidic device, lateral oblique view: ports extending upward from the distal ends provide inlet/outlet access and connection to the pump. The channel has been filled with red dye to make it easily visible. c, d Photomicrographs of the central part of the channel, top-down views. c As the main channel segments approach the central orifice, the walls narrow at 45° angles. d High-magnification view of the orifice. Note the smoothness of the channel walls. The 100-µm-wide channels were not needed or used in the experiments reported here. e A block diagram illustrating the main components of the experimental system. The microfluidic device sits on the stage of a Signatone probe station equipped with an upright compound microscope and computer-controlled CCD camera. One device port is connected by tubing to a computer-controlled syringe pump that drives oscillatory flow within the channel. f–h Individual frames of video acquired during the dissociation of an enzyme-treated piece of rat E18 hippocampus in a microfluidic device. f Intact tissue is driven by the pump through the central orifice with dimensions L = 400 µm, W = 70 µm. g Following oscillatory cycles of flow-induced shear stress (flow rate 50 µl/sec, infusion volume 12.5 µl, 4 Hz), the tissue has been dissociated into cell clusters and single cells. Dotted rectangle indicates approximate size of the area shown in (h) at a later time at higher magnification. h Additional cycles have completed the dissociation into single cells which were collected and plated for culture