Comparing Microfluidic Performance of Three-Dimensional (3D) Printing Platforms

Three-dimensional
(3D) printing has emerged as a potential revolutionary
technology for the fabrication of microfluidic devices. A direct experimental
comparison of the three 3D printing technologies dominating microfluidics
was conducted using a Y-junction microfluidic device, the design of
which was optimized for each printer: fused deposition molding (FDM),
Polyjet, and digital light processing stereolithography (DLP-SLA).
Printer performance was evaluated in terms of feature size, accuracy,
and suitability for mass manufacturing; laminar flow was studied to
assess their suitability for microfluidics. FDM was suitable for microfabrication
with minimum features of 321 ± 5 μm, and rough surfaces
of 10.97 μm. Microfluidic devices >500 μm, rapid mixing
(71% ± 12% after 5 mm, 100 μL/min) was observed, indicating
a strength in fabricating micromixers. Polyjet fabricated channels
with a minimum size of 205 ± 13 μm, and a surface roughness
of 0.99 μm. Compared with FDM, mixing decreased (27% ±
10%), but Polyjet printing is more suited for microfluidic applications
where flow splitting is not required, such as cell culture or droplet
generators. DLP-SLA fabricated a minimum channel size of 154 ±
10 μm, and 94 ± 7 μm for positive structures such
as soft lithography templates, with a roughness of 0.35 μm.
These results, in addition to low mixing (8% ± 1%), showed suitability
for microfabrication, and microfluidic applications requiring precise
control of flow. Through further discussion of the capabilities (and
limitations) of these printers, we intend to provide guidance toward
the selection of the 3D printing technology most suitable for specific
microfluidic applications.