Fig. 3From: Ultrasensitive and rapid count of Escherichia coli using magnetic nanoparticle probe under dark-field microscopeMicroscope images of E. coli at different conditions. a E. coli without MNP probes under a bright field; b E. coli without MNP probes under a dark-field; c E. coli mixed with MNP probes under a bright field; d E. coli mixed with MNP probes under a dark-field; e Transmission Electronic Microscope (TEM) image of E. coli mixed with naked MNPs. f TEM image of . coli with MNP probes. g Salmonella mixed with MNP probes; Red box in the upper right corner of d and e is the enlargement of the selected area, respectivelyBack to article page