Digital Manufacturing of Selective Porous Barriers in Microchannels Using Multi-Material Stereolithography.

Area of Science:

• Materials Science
• Chemical Engineering
• Biomedical Engineering

Background:

• Microfluidic devices are crucial for various applications, including molecular filtration and cell-based assays.
• Fabricating microfluidic devices with integrated porous barriers often involves complex and time-consuming assembly processes.
• Existing methods for creating porous barriers in microfluidics can be costly and prone to complications.

Purpose of the Study:

• To develop a novel, semi-automated 3D printing process for fabricating microfluidic devices with integrated porous barriers.
• To demonstrate the selective diffusion of molecules across these 3D-printed porous barriers.
• To offer a cost-effective and efficient alternative to traditional microfluidic fabrication techniques.

Main Methods:

• Sequential stereolithographic co-printing using two distinct resins: poly(ethylene glycol) diacrylate (PEG-DA) variants for channels and porous barriers.
• Fabrication of microfluidic channels using PEG-DA-258 resin.
• Creation of porous barriers using PEG-DA-575 or 40% PEG-DA-700 resins within the microchannels.

Main Results:

• Successfully fabricated microfluidic chips with integrated porous barriers using a semi-automated 3D printing process.
• Demonstrated selective hydrogen ion diffusion across a 3D-printed PEG-DA-575 porous barrier using phenol red indicator.
• Showcased fluorescein diffusion across a 3D-printed 40% PEG-DA-700 porous barrier by measuring fluorescence intensity.

Conclusions:

• The developed 3D printing method offers a simple, convenient, and reproducible route for fabricating microfluidic devices with selective porous barriers.
• This digital manufacturing approach significantly reduces design and processing time, assembly complications, and manufacturing costs.
• The fabricated devices are suitable for applications requiring controlled molecule delivery, such as molecular filtration and cell-based microdevices.