1. King Abdullah Institute for Nanotechnology King Saud University Riyadh 11451 Saudi Arabia
2. SABIC Polymer Research Center College of Engineering King Saud University Riyadh 11421 Saudi Arabia
3. Cornea Research Chair Department of Optometry College of Applied Medical Sciences King Saud University Riyadh 11433 Saudi Arabia
4. Department of Physics and Astronomy College of Science King Saud University Riyadh 11451 Saudi Arabia