A method for detecting and/or characterizing pathogens present in an isolated test sample, said method comprising: (a) contacting in a vessel comprising a bottom and a wall, and in a buffered aqueous media, the sample where pathogens are to be detected, with a coloured particle comprising: - a core with a surface, said core having a material mass density from 1.5 to 2.5 g/cc; and a diameter from 3 to 10 μm; and wherein at least the surface is coloured and it comprises one or more functional groups selected from -COO-R 1, -NR 2 R 3, and combinations thereof, wherein R 1 is independently selected from H, and (C 1 -C 8)-alkyl, and R 2 and R 3 are independently selected from H, (C 1 -C 8)-alkyl, and (C 1 -C 8)-alkoxyl; and - a pathogen ligand that is a compound comprising a pathogen-recognizing molecular pattern immobilized on the surface of the core; (b) allowing the particles to sediment for a time from 1 to 20 minutes after the contacting step; (c) determining the sedimentation pattern of the particles, wherein particle sedimentation on the bottom or walls of the vessel indicates lack of pathogen in that sample, while the lack or absence of sedimentation is indicative of agglutinated particles, which means that interaction between the pathogen ligand on the surface of the particle and the pathogen in the sample has taken place and that the pathogen has been recognized by pathogen ligand, wherein step (a) is performed at a pH that is higher than the average isoelectric point of the particle, said average isoelectric point provided by the surface electrical charge of pathogen ligand immobilized on the surface of the core of the particle and the functional groups selected from -COOR1, -NR2R3 also on the said core surface of the particle. (a) contacting in a vessel comprising a bottom and a wall, and in a buffered aqueous media, the sample where pathogens are to be detected, with a coloured particle comprising: - a core with a surface, said core having a material mass density from 1.5 to 2.5 g/cc; and a diameter from 3 to 10 μm; and wherein at least the surface is coloured and it comprises one or more functional groups selected from -COO-R 1, -NR 2 R 3, and combinations thereof, wherein R 1 is independently selected from H, and (C 1 -C 8)-alkyl, and R 2 and R 3 are independently selected from H, (C 1 -C 8)-alkyl, and (C 1 -C 8)-alkoxyl; and - a pathogen ligand that is a compound comprising a pathogen-recognizing molecular pattern immobilized on the surface of the core; - a core with a surface, said core having a material mass density from 1.5 to 2.5 g/cc; and a diameter from 3 to 10 μm; and wherein at least the surface is coloured and it comprises one or more functional groups selected from -COO-R 1, -NR 2 R 3, and combinations thereof, wherein R 1 is independently selected from H, and (C 1 -C 8)-alkyl, and R 2 and R 3 are independently selected from H, (C 1 -C 8)-alkyl, and (C 1 -C 8)-alkoxyl; and - a pathogen ligand that is a compound comprising a pathogen-recognizing molecular pattern immobilized on the surface of the core; (b) allowing the particles to sediment for a time from 1 to 20 minutes after the contacting step; (c) determining the sedimentation pattern of the particles, wherein particle sedimentation on the bottom or walls of the vessel indicates lack of pathogen in that sample, while the lack or absence of sedimentation is indicative of agglutinated particles, which means that interaction between the pathogen ligand on the surface of the particle and the pathogen in the sample has taken place and that the pathogen has been recognized by pathogen ligand,