You are here:
Silver nanoparticle toxicity to retinal pigment epithelial cells in vitro is influenced by particle size and coating, but not UVA radiation
Citation:
BOYES, W. K. Silver nanoparticle toxicity to retinal pigment epithelial cells in vitro is influenced by particle size and coating, but not UVA radiation. Presented at Society of Toxicology (SOT) Annual Meeting, San Francisco, CA, March 11 - 15, 2011.
Impact/Purpose:
Silver nanoparticles (AgNP) are being introduced into textiles, medical devices, cleaning/disinfecting products and other goods because of their antibiotic properties. Some nanomaterials, including silver, have been developed into drug delivery systems that can be administered directly to the eye.
Description:
Silver nanoparticles (AgNP) are being introduced into textiles, medical devices, cleaning/disinfecting products and other goods because of their antibiotic properties. Some nanomaterials, including silver, have been developed into drug delivery systems that can be administered directly to the eye. Because the retina is the only part of the nervous system that is exposed to light and because other nanoparticles have demonstrated phototoxicity, human retinal pigment epithelial cells (ARPE-19) were used to test the potential cytotoxicity and. phototoxicity of PVP-and citrate-coated silvernanoparticles(Ag-PVPand Ag-CIT,respectively). Nanoparticles were suspended in cell culture medium with fetal bovine serum (FBS). Suspensions were characterized using dynamic light scattering (Malvern Zetasizer Nano). ARPE19 cells were grown to confluence in DMEM/F12 + 10% FBS and pen/strep and dosed with 0, 3, 10, 30, 55, 100, & 200 ug/rnl of 10, 50, and 75nm Ag-PVP or Ag-citrate (nanoComposix). For phototoxicity tests, the cells were exposed to 2 hrs of either UVA, visible light, or no light exposure 24 hrs after dosing. A live/dead assay (calcein AM/propidium iodide) was used to .measure cell viability either 24 hrs after dosing (cytotoxicity testing) or 24 hrs after dark/light/radiation exposure (phototoxicity testing). Flow cytometry and dark field microscopy were used to verify that the AgNP entered the cells. Flow cytometry showed dose-related increased side-scatter signal consistent with cellular uptake of silver particles. Using darkfield microscopy, silver particles could be observed in the cytoplasm of ARPE-19cells. The cytotoxicity of nano-silver increased with higher doses for all particles, and smaller particles showed more toxicity than larger particles. Nano Ag-PVP appeared to be more potent than equivalent-sized Ag-CIT for 50 or 75 nm particles. No significant differences in cytotoxicity were observed between 10 nm Ag-PVP and 10 nm Ag-CIT. Phototoxicity testing was completed on 10 nm Ag-PVP and 50 nm Ag-CIT, and no differences between nanoparticle-treated cells coexposed to darkness, visible light or UVA were observed. Thus, the toxicity of Ag nanoparticles was influenced by particle size and coatings, but no evidence of phototoxicity was observed. This abstract does not reflect EPA policy.