Rapid and Inexpensive Fabrication of Multi-Depth Microfluidic Device using High-Resolution LCD Stereolithographic 3D Printing

Abstract

With the dramatic increment of complexity, more microfluidic devices require 3D structures, such as multi-depth and -layer channels. The traditional multi-step photolithography is time-consuming and labor-intensive and also requires precise alignment during the fabrication of microfluidic devices. Here, we present an inexpensive, single-step, and rapid fabrication method for multi-depth microfluidic devices using a high-resolution liquid crystal display (LCD) stereolithographic (SLA) three-dimensional (3D) printing system. With the pixel size down to 47.25 μm, the feature resolutions in the horizontal and vertical directions are 150 μm and 50 μm, respectively. The multi-depth molds were successfully printed at the same time and the multi-depth features were transferred properly to the polydimethylsiloxane (PDMS) having multi-depth channels via soft lithography. A flow-focusing droplet generator with a multi-depth channel was fabricated using the presented 3D printing method. Experimental results show that the multi-depth channel could manipulate the morphology and size of droplets, which is desired for many engineering applications. Taken together, LCD SLA 3D printing is an excellent alternative method to the multi-step photolithography for the fabrication of multi-depth microfluidic devices. Taking the advantages of its controllability, cost-effectiveness, and acceptable resolution, LCD SLA 3D printing can have a great potential to fabricate 3D microfluidic devices.

Evaluation of Lateral and Vertical Dimensions of Micromolds Fabricated by a PolyJet™ Printer

“…Microfluidic devices fabricated by soft lithography are primarily planar with uniform height. Multiple steps are involved to fabricate non-planar 3D microchannels with varying heights [ 16 ]; non-planar microchannels are a requisite for applications such as droplet generation and manipulation [ 17 , 18 , 19 , 20 , 21 ], biological flow units [ 22 , 23 ], and soft robots [ 24 ]. For example, an additional dimension of non-planar channels permits the complex actuation of robotic structures; non-planar channels also allow handling fluids with different wettability without any modification to the surface.…”

Study of Microchannels Fabricated Using Desktop Fused Deposition Modeling Systems

“…The performance of 3D-printing devices depends upon the choice of process. In microfluidic applications, Stereolithography (SL) printing has been employed widely which works on the principle of curing a photopolymer resin layer-by-layer [ 35 , 36 ]. However, conventional SL resin is susceptible to toxicity and is not biocompatible [ 37 ].…”

Facile Fabrication of Microfluidic Chips for 3D Hydrodynamic Focusing and Wet Spinning of Polymeric Fibers

“…Recent advances in additive manufacturing have allowed rapid prototyping of devices with high versatility and precision [17]. While conventional fused deposition modeling (FDM) 3D printers fail to produce microfluidic coaxial reactors due to the inherent x-y low resolution [18][19][20][21], digital light processing (DLP) and masked stereolithography (MSLA) printers have recently shown the possibility to produce transparent microfluidic devices with the single-pixel resolution higher than 47 µm [22][23][24][25][26][27]. However, the channel geometry [27], produced in a layer-by-layer fashion, may affect the flow behavior and therewith the resulting fiber morphology, similar to what was shown by using chevrons [28].…”