Toxicity of nanomaterials to the eye

What do nanoparticles offer drug delivery to the eye that traditional formulations do not? The underlying concept of nanomedicine is that the nanomaterials have properties that their constituent components do not have. These unique properties are the benefit, but the cost can be more a complicated toxicology assessment. Ocular delivery of therapeutic nanoparticles has the potential to greatly increase the quality of life through maintaining our vision. The eye is composed of multiple tissue types, i.e., epithelium, muscle, immune cells, neural cells, and blood vessels, to name a few. Ocular diseases affect many of these tissues at once. Introduce novel therapeutic nanoparticles and determining mechanisms of toxicity becomes challenging. This review is a survey of what is known about toxicity in experimental nanoparticles for ocular therapeutics. Specific cases are chosen to illustrate a range of toxic effects of nanoparticles in the eye. There is a unique research opportunity for in-depth toxicology studies of nanoparticles in the eye. This has been made possible by the rapid development of therapeutic nanoparticles in the last few years. (C) 2009 John Wiley & Sons, Inc. WIREs Nanomed Nanobiotechnol 2010 2 317-333