The main idea of this project is to construct a multi-detection sensor based on bacteriophages, or aptamers, or ideally their combination, in the analysis of selected diseases or in wastewater-based epidemiology management. Because it is intended to immobilize the phages/aptamers specific to each target analyte (bacteria/virus) on the surface of the electrode, the immobilization process will be optimized in order to create a stable and uniform biolayer for simple, one-step, and multiplex determination of pathogens. Each phage/aptamer is expected to specifically bind to the analyte-pathogen. Assuming successful results, the proposed procedure will be tested on a lab scale, i.e., wastewater model samples from selected wastewater treatment plants. The principle of the detection will be based on sensitive electrochemical techniques (such as pulse voltammetry and electrochemical impedance spectroscopy) complete with color or fluorescence-based tests.