Patterning Biological Gels for 3D Cell Culture inside Microfluidic Devices by Local Surface Modification through...

Area of Science:

• Biomedical Engineering
• Microfluidics
• Biomaterials Science

Background:

• Microfluidic devices are crucial for in vitro cell culture, particularly organs-on-chips.
• Patterning biological hydrogels provides controlled 3D microenvironments for cells.
• Existing hydrogel patterning methods often require costly fabrication and use non-physiological structures.

Purpose of the Study:

• To develop a facile hydrogel patterning technique for microfluidic devices.
• To overcome limitations of existing methods, such as cleanroom fabrication and non-physiological structures.
• To improve the design flexibility and physiological relevance of microfluidic cell culture models.

Main Methods:

• Utilized laminar flow patterning to create hydrophilic paths within hydrophobic microfluidic channels.
• Confined liquid hydrogels to these hydrophilic paths for precise geometry formation.
• Demonstrated patterning in various channel geometries with control over gel parameters.

Main Results:

• Successfully patterned hydrogel geometries without built-in channel confinement.
• Cultured human umbilical vein endothelial cells within patterned hydrogels for multiple days.
• Showcased cell migration into hydrogels under trans-gel flow and confirmed gel stability under physiological flow conditions.

Conclusions:

• The novel technique offers facile and versatile hydrogel patterning in microfluidics.
• It eliminates the need for complex fabrication and non-physiological structures.
• This method enhances the physiological realism and design efficiency of organs-on-chips and cell culture assays.