Prototyping of Microfluidic Devices in Poly(dimethylsiloxane) Using Solid-Object Printing

Abstract

A solid-object printer was used to produce masters for the fabrication of microfluidic devices in poly(dimethylsiloxane) (PDMS). The printer provides an alternative to photolithography for applications where features of > 250 microm are needed. Solid-object printing is capable of delivering objects that have dimensions as large as 250 x 190 x 200 mm (x, y, z) with feature sizes that can range from 10 cm to 250 microm. The user designs a device in 3-D in a CAD program, and the CAD file is used by the printer to fabricate a master directly without the need for a mask. The printer can produce complex structures, including multilevel features, in one unattended printing. The masters are robust and inexpensive and can be fabricated rapidly. Once a master was obtained, a PDMS replica was fabricated by molding against it and used to fabricate a microfluidic device. The capabilities of this method are demonstrated by fabricating devices that contain multilevel and tall features, devices that cover a large area (approximately 150 cm2), and devices that contain nonintersecting, crossing channels.

Developing a Protocol for Creating Microfluidic Devices with a 3D Printer

“…Using the Makerbot Replicator 2X and the simplest single casting technique, we were able to achieve channel width dimensions under 0.3 mm, similar to dimensions that other researchers, such as McDonald et al (2002), have reported. An early prototype device is shown in Figure 1.…”

“…The templates can then be cast with polydimethylsiloxane (PDMS) and subsequently cured. The PDMS mold can be removed from the master and adhered to a glass slide, creating the fourth wall of the microfluidic channels (Au et al 2016;Bishop et al 2015;Kitson et al 2012;Lee et al 2014;McDonald et al 2002;Rogers et al 2015;Whitesides and Stroock 2001).…”

Design and fabrication of chemically robust three-dimensional microfluidic valves

“…19,21 These effects limit the usefulness of fluidic systems with dimensions much below the channels and valves that we describe here. Rapid prototyping of microfluidic devices with a solid-object printer has also been reported by the Backhouse 21 and Whitesides 22 groups, but neither group demonstrated devices with integrated microvalves without bonding, because the printers employed were only capable of generating essentially two-dimensional patterns.…”

“…[1][2][3][4][5][6][7][8][9][10][11][12][13][14][15][16][17] PDMS offers the advantages of being inexpensive and simple to fabricate using rapid prototyping. [3][4][5] It exhibits elastomeric properties with a surface energy of y20 erg cm 22 and low Young's modulus value of y750 kPa, thus allowing the material to conform and easily seal to other surfaces, both reversibly and irreversibly. 7 Despite the advantages of PDMS in microfluidic applications, one of the most prominent drawbacks with its use is its incompatibility with many organic solvents including acyclic and cyclic hydrocarbons (e.g.…”

A polymeric master replication technology for mass fabrication of poly(dimethylsiloxane) microfluidic devices

“…A patterned high-resolution transparency mask instead of a chrome mask was employed to rapidly create the photoresist master. With this technique, PDMS microfluidic devices .20 mm can be produced at low costs within 24 h. Subsequently, Whitesides et al [24] developed another prototyping approach for creating three-dimensional masters for molding PDMS devices using the solid-object printing technique. The design of the three-dimensional microstructure was made by using a computer-aided design (CAD) program.…”