Adhesion of Protein Transferrin on FDA Group II Omafilcon Contact Lenses

Adhesion of Protein Transferrin on FDA Group II Omafilcon Contact Lenses

Out of the estimated 200 proteins in tear fluid, which promote the health of ocular surface, 60 proteins have been identified. Bacterial infections of the ocular surface are associated with higher concentrations of tear proteins adhering to contact lenses. The adhesion of the tear protein transferrin to Omafilcon contact lenses, manufactured from a biomimetic material, was investigated. Tear proteins are known to have a charge character that is dependent on pH levels. This charge interaction between tear proteins and the matrix of the contact lens, which also has a charge, increases tear protein adhesion and compromises lens wearing comfort. Never worn Omafilcon contact lenses were incubated from one to five days in human transferrin in borosilicate glass vials. Bicinchoninic acid colorimetry was performed daily to determine tranferrrin concentration in the vials and protein adhesion to lenses. Variation in tear protein adhesion to contact lenses was evident over the five day period. The adhesion of transferrin to the Omafilcon lenses was similar to the adhesion of transferrin to Hilafllcon lenses (both classified as FDA Group II: nonionic high water), but the adhesion of transferrin to the Omafilcon lenses was different from the adhesion of lysozyme to the same lenses. Future analysis involves investigating levels of albumin adherence to Omafilcon contact lenses.