The macroscopic material properties (elasticity, volume in swollen state) of smart stimuli-sensitive hydrogels show a strong dependence on the properties of an aqueous environment (swelling agent). This behavior can be used for sensors or force-generating elements (actuators). Radiochemistry offers the possibility to synthesize smart gels in a wide range of dimensions. As an example of temperature-sensitive polymers we demonstrate the advantages of a radiochemical-based approach for hydrogel synthesis. Structures in the μm and sub-μm range on a support were synthesized using different techniques. The applications of particles and patterned layers in the μm range were demonstrated using the example of devices for handling liquids