GelMA (gelatin methacrylate) is a gelatin-based hydrogel that reacts and crosslinks in the presence of LAP and Allevi blue light technology (1,2). The recommended preparation provided in the user instruction below yields a streamlined matrix bioink that supports 3D bioprinted cell-laden constructs. However, preparation can be modified by users to suit their needs. Follow this step-by-step guide for bioprinting gelMA in your lab.
- Cell media
- Plastic syringe (5mL or 10 mL)
- Syringe filter
- Syringe coupler
- Petri dish or well plate for printing
- Optional: Glass slide (glass slide treatment protocol)
- Mix LAP in 3 ml of PBS or cell media at 60°C under stirring to create a 0.5% w/v LAP concentration. Mix until all LAP is dissolved.
- Add GelMA to solution to create a 10% w/v concentration. Mix at 60°C under stirring until all GelMA is dissolved. Be sure the container is tightly sealed while mixing to avoid evaporation of solution.
- Keep GelMA at 60°C and filter with syringe filter under sterile conditions.
- In a sterile environment, cool solution to 37°C and load into syringe A.
- Under sterile conditions and while solution in syringe A is still at 37°C, load concentrated cell solution into syringe B and mix with solution in syringe A using a syringe coupler. Be sure to mix thoroughly to create a homogenous solution.
- Once solution is thoroughly mixed, transfer entire mixture to syringe A, then remove syringe B from syringe couple and replace with an empty syringe (syringe C). Transfer entire solution to syringe C.
- Remove syringe coupler and place plastic bioprinting tip (Guide to Picking Your Bioprinting Needle) on syringe C, then load into the Allevi bioprinter.
- Cool extruder until bioink reaches 22°C.
- Prepare your design file on the Allevi software and use the print settings outlined below.
|Speed (mm/s)||Layer height (mm)||Nozzle Diam (mm)||Gauge||Pressure (PSI)||Print Temp (°C)|
*Critical step: Your needle can have significant effects on print settings. Be sure to use the suggested needle type or re-calibrate print parameters.
|Crosslinking light||Intensity||Frequency||Duration (s)|
|Crosslinking light||Intensity||Duration (s)|
- Issues with gelMA bioprinting? Check out our Troubleshooting Guide.
- Gelation time and gel stiffness can be adjusted by varying the concentration of GelMA or LAP. For help adjusting print parameters please contact [email protected]
- A fill volume change of more than 2 ml may affect pressure settings.
- A lower gauge size or tapered gauge will require a lower pressure, while a higher gauge will require a higher pressure for extrusion. Lowering the gauge size will also generally lower resolution
We hope that you found this step-by-step guide for bioprinting gelMA useful! You are now ready to analyze and image your bioprinted construct. Click here for post-printing analysis protocols.
 D. B. Kolesky et al, “3D Bioprinting of Vascularized, Heterogeneous Cell-laden Tissue Constructs,” Adv. Mater., vol. 26, pp. 3124-3130, 2014.
 B. D. Fairbanks et. al, “Photoinitiated Polymerization of PEG-diacrylate with lithium phenyl-2,4,6-trimethylbenzoylphosphinate: polymerization rate and cytocompatibility,” Biomaterials, vol. 30, no. 35, pp. 6702-6707, Dec 2009.