Physiological relevance in 3D cell culture models can be increased using scaffold-based models. The Scaffold-based models provide in vivo-like tissue stiffness and Cell-Matrix interactions to support correct cell phenotype formation. 3D cell culture scaffolds consist wide range of biomaterials. Depending on their origin, Biomaterials can be divided into synthetic or natural materials. One sub-category of scaffold materials are hydrogels. Hydrogels are usually classified into three categories which are synthetic, animal-derived and plant-derived polymers. These polymers have high capacity to retain large amounts of water and are commonly used in 3D cell culture.
A commonly used hydrogel 3D cell culture application is the embedding. Embedding process of cells in hydrogel consists of couple steps for ensuring the even distribution of cells. Cells are mixed with hydrogel and added to the culture vessel, such as 96-well plate, followed by dispensing the culture medium on top of the gel. Embedded cells produce heterogenous populations of spheroids. Depending on the origin of the hydrogel, preparation steps can slightly vary.
The origin source of the hydrogel can bring its own advantages and disadvantages. Hydrogels that are temperature sensitive and need certain temperature for handling and polymerization are challenging for HTS applications because the temperature needs to be adjusted. Moreover, in animal-derived hydrogels exact compound content is not known and there can occur batch-to-batch variation. In long-term 3D cell culture, animal-derived hydrogels that contain collagen and hyaluronic acid can be degraded enzymatically by cultured cells, causing a structural change over time.
When considering hydrogel embedding in high content screening (HCS) applications easy degradation and transparency of hydrogels are essential properties. Retrieving cells for RNA/DNA extraction, the hydrogel embedding is noticed to be challenging for some hydrogels. Synthetic hydrogels cannot be degraded, and animal-derived matrix degradation affects cell surface proteins of cultured cells.