Comparing nanoparticle physical properties with bio-uptake

Bibliography: p. 115-127Some pages are in colour.Nanoparticle-organismal interactions depend on nanoparticle (NP) physical properties and tissue type. Angiogenic vasculature, characteristic of neoplastic diseases and developing tissues, has fenestrations between endothelial cells in which NPs can accumulate. This phenomenon is integral to nanomedicine and nanotoxicology, so we systemically injected dye-impregnated, polystyrene FluoSpheres (FS) into angiogenic chicken embryo chorioallantoic membrane (CAM) to determine bioaccumulation patterns and associated kinetics within the blood. FS concentration was monitored in the CAM using two-photon excitation fluorescence correlation spectroscopy and bio-uptake rate constants in flowing vessels were determined. Negatively charged, carboxylate-coated FS under 500 nm in diameter showed uptake in flowing vessels, while amine FS immediately agglomerated and adhered to the endothelium. Carboxylate FS uptake rate constants showed linear dependence on R-;/, indicating that NP surface area footprint determines uptake rates. A predictive bio-uptake model was developed based on NP physical properties, which clarifies the passive nature of NP uptake into angiogenic tissues