BIOMONAR develops multiplexed nanoarray biosensors for environmental targets, i.e. pollutants and pathogens. The innovative approach engineers three sensor platforms (surface, liposomal, living cell) which exploit a panel of periplasmic binding proteins (PBPs) as the common selective element. The nanoarrays are integrated into a microfluidics system for in-situ monitoring. The strategy allows for selective and sensitive detection of target compounds in complex environmental mixtures. The sensor platforms probe different aspects in the ‘exposure to effect’ chain of processes: each responds to a certain proportion of the total target concentration and has a characteristic dynamic window. The sensor signals are quantitatively interpreted and represented in terms of the spectra of reactivities and fluxes of the target compounds. This level of sophistication, coupled with the common PBP selective component, allows a coherent elucidation of the link between dynamic target speciation and predicted ecotoxicological impact. The optimisation and dedication of the sensors for environmental monitoring inherently involves physicochemical characterisation of the various bio/nonbio and bio/bio interfacial processes at nanoscale. The ensuing knowledge on the interaction of nanostructured surfaces with biological systems facilitates design of sensors for new targets, thus providing technical opportunities for the biosensor industry.