Abstract:

BACKGROUND: The contact lenses were easily contaminated by adsorbing components from the tear film, particularly protein after wearing for a period of time. Lysozyme adsorption dynamics of ?uorosilicone acrylate contact lenses has been studied in order to further improve data of protein adsorption, reduce adsorbing amount of surface protein, and prevent surface contamination of contact lenses.
OBJECTIVE: To investigate the adsorption dynamics of ?uorosilicone acrylate contact lenses to lysozyme in vitro.
METHODS: A stock solution of lysozyme was prepared in Hanks balanced salt solution (2.0 g/L, solution I) and different trifluoroacetic acid (TFA) concentrations were prepared. Recovery experiment, the contact lenses were placed in shaking incubator at 37 ℃ for varying time intervals. After incubation there was a single rinsing in Hanks balanced salt solution. Contact lenses in control group were placed in diluted water, and contact lenses in the other group were placed in different concentrations of TFA. For deposition, FSA contact lenses in experimental group were placed in shaking incubator at 37 ℃ for varying time intervals. After incubation there was a single rinsing in Hanks balanced salt solution. Then FSA contact lenses were immersed in 0.2% TFA solution. The amount of lysozyme was assayed with BCA method.
RESULTS AND CONCLUSION: Lysozyme which attached to ?uorosilicone acrylate contact lenses could be resolved by TFA, and the recovery was influenced by the immersed time and the concentration of TFA. The optimal time was 1 hour, and the optimum concentration was 0.2%. The adsorption dynamics of lysozyme on FSA contact lenses was a second-phased process, i.e., lysozyme adsorption increased rapidly during 10 minutes-1 hour, reached a plateau at 1 hour, stably adsorbed during 1-24 hours, and reached a saturation of 0.349 mg/cm². The recovery of lysozyme was lower at 10 and 30 minutes, but reached 90%-100% while the time of incubation was between 40 minutes and 24 hours.