Fig. 4From: Detection, counting and characterization of nanoplastics in marine bioindicators: a proof of principle studyRepresentative SEM images of the different fractions of PS nanoparticles as spotted on the silicon-FDTS-PDDA surface by manual spotting. The number after the sample name (1–3) corresponds to the fraction number, A, B, and C indicates the sample, with PS exposure increasing from A to CBack to article page