Imaging and organelle distribution of fluorescent InGaP/ZnS nanoparticles in glial cells.

To assess the effects of oleic acid treatment on subcellular distribution of indium gallium phosphide-zinc sulfide (InGaP/ZnS) nanoparticles in microglia and astrocytes. The extent of colocalization between the nanoparticles and organelles was assessed by confocal microscopy, spectrofluorometry and cell sorting. Cell treatment with a common fatty acid (oleic acid) within the range of physiological concentrations markedly enhanced the InGaP/ZnS uptake by microglia and afforded their colocalization within lipid droplets/lysosomes but not with mitochondria. These results suggest that the availability of mono-unsaturated fatty acids, such as oleic acid, in different cells could significantly alter nanoparticle uptake and localization, which can in turn affect the functions of cells and tissues coexposed to nanoparticles.