Translocation of fluorescently labelled nanoparticles in the model organism <i>C. elegans</i> is dependent on their composition.

(a)Note that fluorescent signals from polystyrene-NPs are intrinsically stronger versus silica-NPs. YO represents the strongest fluorochrome. It was determined by Fluorescence Correlation Spectroscopy (FCS) that neither of the fluorochromes uncoupled from the respective nanoparticles (Hemmerich and von Mikecz, unpublished results). (b)Detection of NPs was scored as positive or negative without grading of signal intensity. Carboxy, carboxyl groups on particle surface; NPs, nanoparticles; YG, yellow-green; YO, yellow-orange.