In this study, the surfaces of two gold nanoparticles of different shapes were modified with hexadecyltrimethylammonium bromide (CTAB) and used for contact lenses. The polymer was based on 2-hydroxyethyl methacrylate (HEMA), and spherical and sea urchin-shaped gold nanoparticles were used as additives. CTAB was used to modify the surface of the sea urchin-shaped gold nanoparticles. To analyze the physical properties of the prepared contact lens, optical transmittance, refractive index, water content, contact angle, and atomic force microscope (AFM) were measured and evaluated. The results showed the nanoparticles did not significantly affect optical transmittance, refractive index, or water content of the lens, and tensile strength increased according to the ratio of the additive. The addition of the sea urchin-shaped nanoparticles resulted in lower wettability compared with the spherical nanoparticles, but somewhat superior tensile strength. In addition, it was found that the wettability of the lens was improved when the surface-modified sea urchin-shaped gold nanoparticles were added. The types of gold nanoparticles and surface modification methods used in this study are considered to have great potential for use in ophthalmic materials.

1. Introduction
2. Experimental Procedure
    2.1. Hydrogel contact lens
    2.2. Hydrogel contact lens containing gold nanoparticles
    2.3. Surface modification of gold nanoparticles
    2.4. Analysis
3. Results
    3.1. Properties based on the shape of gold nanoparticles
    3.2. Properties based on surface-modified goldnanoparticles
4. Discussion
5. Conclusion
Acknowledgement
References
Author Information

• A-Young Sung(Department of Optometry & Vision Science, Daegu Catholic University, Gyeongsan 38430, Republic of Korea) Corresponding author
• Su-Mi Shin(Department of Optometry & Vision Science, Daegu Catholic University, Gyeongsan 38430, Republic of Korea)
• Seon-Young Park(Department of Optometry & Vision Science, Daegu Catholic University, Gyeongsan 38430, Republic of Korea)