Biofilm, the predominant lifestyle of all bacterial species, is a form of bacterial growth that enhances survival in wetted natural and artificial environments. The accompanying resilience, including decreased susceptibility to disinfectants and antibiotics, increases the need for prevention of biofilm formation, particularly on implanted medical devices and on food contact surfaces. This has prompted a revision of traditional methods and practices, re-evaluating them in relation to bacterial adherence and growth. The metabolism of bacteria growing in biofilms compared to those undergoing planktonic growth differs vastly. One important determinant is the redox state of the microenvironment in which bacteria exist. Sensing of the environmental redox state controls the switch between aerobic and anaerobic metabolism as well as bacterial virulence. We showed previously that electrically charged surfaces with high charge storage capacity, like PEDOT-based conducting polymers, can be used to modulate biofilm formation by altering the redox states of the surfaces [1, 2]. To gain better understanding of this finding, we performed an in-depth analysis of the process of biofilm formation on redox-challenged PEDOT:PSS surfaces using GFP-expressing Salmonella and the optotracer EbbaBiolight 680. The latter is a non-toxic fluorescent tracer that allowed us to monitor and quantify the production of extracellular matrix components (ECM) in real-time by semi-quantitative spectroscopy and microscopy [3]. Redox challenge performed in a fast-charging electrochemical setup promoted bacterial production of higher amounts of cells and ECM on oxidized PEDOT:PSS surfaces compared to their reduced counterpart. When electrodes were separated and charging was carried out with respect to a Pt electrode, the slower charging process resulted in increased cell numbers as well as increased amount of ECM on the reduced surfaces. When isogenic Salmonella mutants unable to produce the ECM components curli and/or cellulose were tested, none of them responded to the redox challenge. This demonstrates a novel use of surface redox potential to modulate ECM curli production and accordingly biofilm formation. Anti-biofouling surfaces directly affecting ECM production may find use in sensitising biofilm forming strains to the effect of antibiotics and antimicrobial compounds.