3D Sacrificial Microchannels by Scaffold Removal Process for Electrical Characterization of Electrolytes

3D printing technology is promising for the fabrications of microfluidic devices. For both research and educational purposes, the efficient generations of highly organized microchannels are on demand. Here, we suggest a method to create 3D helix microchannels by using a 3D printed scaffold as sacrificial material for an acetone-treated removal process. We employed a desktop fused deposition modeling (FDM) 3D printer which is friendly used for cheap-and-easy processes. 3D scaffold structures were made of acrylonitrile/butadiene/styrene (ABS) plastic via the FDM 3D printer. To increase the stability of the fabrications of polydimethlysiloxane (PDMS) fluidic chambers, we developed a double PDMS casting process. As a frame layer, the first PDMS was casted in the space between a vertically standing 15 ml conical tube and a vacant 50 ml conical tube. Inside the PDMS frame layer, the second PDMS mixture solution was poured, followed by immersing the 3D printed scaffold. After curing, the PDMS block was shaped with a cutter, thus leaving both ends of the 3D scaffold open. For the removal and rinsing process, the PDMS block with the 3D scaffold were dipped in acetone and rinsed by chloroform, sequentially. Since the 3D printed ABS plastic was dissolved in acetone, the 3D scaffold was converted into 3D microchannel. The 3D sacrificial microchannels described here provide an insight for simple fabrications of 3D microfluidic structures. Graphical Abstract: [Figure not available: see fulltext.].