The research mainly involved in the fundamental investigations concerning electrochemical (bio) sensors based on integrated micro- & nanostructures and nanocomposites, where electrochemical reactions are used to manipulate and/or quantify very small amounts of compounds. It is further involved in the development of novel electrochemical sensing approaches or creating novel sensing platforms based on the combination of nanomaterials with electronically conducting polymers, novel doped / functionalized carbon matrix and microfabricated arrays of micro- or nanoelectrodes. The sensing is based on the voltammetric, potentiometric, amperometric and impedimetric protocols, which are intended to be, carried both in micro or macro batch mode of experiments. The proposed combination of techniques enables the design of very small and versatile sensors suitable for inclusion in e.g. personal diagnostic devices and on-site real-time environmental monitoring units.