The field of tissue engineering has gained in importance in recent years, as it makes it possible to artificially produce organ and tissue models. In the long term, artificially produced organs are to be used in the field of organ transplantation or drug screening. One possibility to generate such models is 3D bioprinting. Here, hydrogels that can be loaded with different types of cells are used as the ink, also known as bioink. These hydrogels must meet certain requirements so that the cells can be cultivated in them. First, the hydrogel should mimic the extracellular matrix as far as possible, since this is the natural environment of the cells, and the cells within the hydrogel should have the possibility of proliferation, migration and differentiation. Second, the hydrogel must be able to withstand the mechanical demands of 3D bioprinting. The aim of my project is to develop suitable hydrogels for certain cells that meet the requirements and to use them in the 3D bioprinting process to produce organ models, such as a heart model.