With the advent of deep-space exploration, effective shielding strategies are being developed to protect astronauts from ionizing cosmic radiation (ICR). Among the whole ICR spectrum, galactic cosmic rays (GCR) are contributing most to the experienced intravehicular equivalent dose, as current shielding materials used in spacesuits and -crafts can barely shield against them. For long missions, including a mission to Mars, efforts must be undertaken to improve the current materials, and thus minimize the biological impact of ICR on astronauts. Since low-Z elements, such as hydrogen, have demonstrated superior shielding properties against ICR, we will develop (bio)polymer-based water-containing hydrogels and expose them to GCR-like radiation. To further enhance their shielding capabilities, these hydrogels will be doped with high-Z gadolinium nanoparticles to mitigate produced secondary neutrons and photons. Next, we will employ matrix-based kinetic Monte Carlo simulations to gain insight into radiation-material interactions. Additionally, an engineered skin tissue and blood model will be subjected to GCR-like radiation while being shielded by our hydrogels. This will allow us to assess their protective efficacy through radiobiological readouts, including DNA damage, DNA repair kinetics and inflammation. Through this interdisciplinary approach, we aim to develop advanced hydrogel shielding materials with strong potential to safeguard astronauts on long-term space missions.