The present invention relates to a family of fluorescent compounds based on the BODIPY scaffold, and methods for the preparation of said compounds. The present invention further relates to the use of said compounds for the detection of bacterial biofilms, wherein the bacterial biofilm comprises Pseudomonas aeruginosa and the compound specifically binds to a Fap protein of Pseudomonas aeruginosa, or wherein the compound specifically binds to bacterial cells that contain high levels of cyclic-di-guanosine-monophosphate (c-di-GMP).