Micropatterning of 3D Microenvironments for Living Biosensor Applications

Area of Science:

• Biomaterials Science
• Cell Biology
• Biofabrication

Background:

• Micro-scale printing and patterning of living cells is crucial for tissue engineering and biosensor development.
• Existing methods face challenges in achieving precise cellular arrangement and maintaining cell viability.

Purpose of the Study:

• To develop a novel micron-scale quill-pen based printing method for mammalian cells.
• To create biocompatible 3D hydrogel matrices for cell encapsulation and patterning.
• To demonstrate the utility of this method for fabricating functional cell-based biosensors.

Main Methods:

• Modification of a molecular printing instrument (Bioforce Nano eNabler) for quill-pen based cell printing.
• Utilizing photo-initiated thiol-ene click chemistry for hydrogel formation using hyaluronan/gelatin and polyethylene glycol (PEG)-norbornene.
• Encapsulating and patterning mammalian cells (human adipose-derived stem cells, NIH-3T3 cells, mouse embryonic stem cells) within the hydrogel matrix.
• Assessing cell viability and functionality using a redox-sensitive green fluorescent protein (roGFP-R12) reporter.

Main Results:

• Successful micron-scale printing and patterning of living mammalian cells in a 3D hyaluronan/gelatin hydrogel.
• Demonstrated biocompatibility of the hydrogel with multiple cell types.
• Engineered micro-printed cells exhibited a measurable fluorescent response to redox changes, indicating functional biosensing capabilities.

Conclusions:

• This work introduces a novel and effective approach for micron-scale cell patterning using quill-pen based printing.
• The developed method offers a versatile platform for creating advanced cell-based biosensors with high spatial control.
• The biocompatible hydrogel and precise cell patterning hold significant potential for regenerative medicine and other biofabrication applications.