Reproducible preparation method of hydrogels for cell culture applications - case study with spermidine crosslinked gellan gum

Hydrogels are promising materials to culture cells in 3D environment. Their mechanical properties are decisive, as cells understand the stiffness of their surroundings. Herein, a method is presented to produce ionically crosslinked hydrogel matrices. A reproducible method is needed, because conventional methods cause inconsistent properties. The investigated material is gellan gum, crosslinked with the bioamine spermidine. Samples were prepared with the more conventional 'pipetting' technique and with self-developed 'uniform mixing' technique. The two preparation techniques are described in detail and the obtained hydrogels are compared. The mechanical properties are analyzed with compression testing. The obtained results show that samples by the so-called 'uniform mixing' method have more uniform dimensions and higher compression modulus. A preliminary stability test in cell culture medium was also carried out.