The role of the coating and aggregation state in the interactions between iron oxide nanoparticles and 3T3 fibroblasts

Recent nanotoxicity studies revealed that the physico-chemical characteristics of engineered nanomaterials play an important role in the interactions with living cells. Here, we report on the toxicity and uptake of the iron oxide sub-10 nm nanoparticles by NIH/3T3 mouse fibroblasts. Coating strategies include low-molecular weight ligands (citric acid) and polymers (poly(acrylic acid), MW = 2000 g mol-1). We find that most particles were biocompatible, as exposed cells remained 100% viable relative to controls. The strong uptake shown by the citrate-coated particles is related to the destabilization of the dispersions in the cell culture medium and their sedimentation down to the cell membranes.