The transparency of the eye lens is vital for maintenance of good image quality to the eye. This is lost when the lens develops a cataract which is a manifestation of changes to the structural proteins and their organisation. Understanding the complex arrangements and interactions of proteins in the lens and how these alter with opacification requires a means of probing the intact tissue. Nanoparticles offer such potential but need to be tested on lens cells and proteins to see whether they cause any detrimental changes. Cerium oxide nanoparticles (nanoceria) of around 5-6nm were prepared and characterised. A concentration of 10μg/ml was introduced into cell cultures from porcine eye lens epithelial cells and from a commercially available human cell line. Transmission electron microscopy of treated samples showed nanoparticles within cells. Proteins extracted from the cultured cells were subjected to chromatography and electrophoresis. Chromatographs and electrophoresis gels showed no difference between treated and control samples from human lens cell cultures. Some slight differences, between treated and control samples, were noted in porcine samples. The results suggest that introduction of nanoceria into cultured cells from the eye lens do not manifest any significant effects on chromatographic or electrophoretic profiles of eye lens proteins.