AbstractBackgroundBacteria of the genusBartonellaare responsible for a large variety of human and animal diseases. Serological typing ofBartonellais a method that can be used for differentiation and identification ofBartonellasubspecies.ResultsWe have developed a novel multiple antigenic microarray to serotypeBartonellastrains and to select poly and monoclonal antibodies. It was validated using mouse polyclonal antibodies against 29Bartonellastrains. We then tested the microarray for serotyping ofBartonellastrains and defining the profile of monoclonal antibodies.Bartonellastrains gave a strong positive signal and all were correctly identified. Screening of monoclonal antibodies towards the Gro EL protein ofB. clarridgeiaeidentified 3 groups of antibodies, which were observed with variable affinities againstBartonellastrains.ConclusionWe demonstrated that microarray of spotted bacteria can be a practical tool for serotyping of unidentified strains or species (and also for affinity determination) by polyclonal and monoclonal antibodies. This could be used in research and for identification of bacterial strains.