The subject of my PhD project includes the development, modification, and characterization of nanomaterials exhibiting catalytic properties in reduction reactions for bioanalytical (biosensors and point-of-care tests) and environmental applications. The aim of the work is to utilize the catalytic properties of nanomaterials to lower the detection limit and limit the uncontrolled formation of the catalyzed reaction product, which is responsible for the generation of an analytical signal. I focus my attention, in particular, on a group of substrates not previously used in the context of point-of-care devices.