Progress in advancing a system-level understanding of the complexity of human tissue development and regeneration is hampered by a lack of biological model systems that recapitulate key aspects of these processes in a physiological context. Hence, growing demand by cell biologists for organ-specific extracellular mimics has led to the development of a plethora of 3D cell culture assays based on natural and synthetic matrices. We developed a physiological microenvironment of semisynthetic origin, called gelatin methacryloyl (GelMA)-based hydrogels, which combine the biocompatibility of natural matrices with the reproducibility, stability and modularity of synthetic biomaterials. We describe here a step-by-step protocol for the preparation of the GelMA polymer, which takes 1–2 weeks to complete, and which can be used to prepare hydrogel-based 3D cell culture models for cancer and stem cell research, as well as for tissue engineering applications. We also describe quality control and validation procedures, including how to assess the degree of GelMA functionalization and mechanical properties, to ensure reproducibility in experimental and animal studies.
At a glance
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- Supplementary Figure 1: Hydrogel casting mould. (113 KB)
Technical drawing and dimensions for the custom-made Teflon casting mould. This mould produces hydrogel strips of 50 mm x 4 mm x 2 mm (length x width x height), which can be cut into smaller units using a cutting guide. All dimensions are in mm.
- Supplementary Figure 2: Hydrogel cutting guide. (93 KB)
Technical drawing and dimensions for the custom-made Teflon cutting guide. This guide can be used to cut hydrogel strips obtained after polymerization in the Teflon casting mould into smaller units of 4 mm x 4 mm x 2 mm (length x width x height). All dimensions are in mm.
- Supplementary Text and Figures (324 KB)
Supplementary Figures 1 and 2