Development of Instant Measuring Model for Oxygen Permeability and Water Content of Hydrogel Contact Lens

Chih-Wei Hung, Kuo-Cheng Huang, Hsin-Yi Tsai, Yu-Hsuan Lin, Patrick Joi-Tsang Shum

Abstract

The diffusion coefficient D, gas solubility k of material and the thickness of lens t were used to evaluate the oxygen permeability Dk/t of contact lenses (CLs). However, the nominal value Dk/t is usually not consistent with the actual oxygen permeability of wearing CL. As the oxygen travel through the hydrogel, it need to be carried by water molecules in the lens material; thus, the higher the water content (WC) of the material, the higher the Dk/t value. In order to obtain the WC and Dk/t of wearing CL, we create a testing platform to simulate the wearing status of CL. When the light traveled through the lens, we found that the attenuation in green light is smoother than other wavelengths. Moreover, the WC is higher, its dewatering rate at room temperature is lower, and the light attenuation is relatively smaller. Comparing with the other CL of similar WC, the Dk/t of CL is higher if it has higher dehydration. In the study, we evaluated the WC and Dk/t of hydrogel CL based on the light attenuation in eight minutes. The attenuation degree of light after traveling through the CL can be used to estimate the Dk/t of hydrogel CL.

References

  1. ISO 11539: 1999. Ophthalmic Optics- Contact LensesClassification of Contact Lenses and Contact Lens Material.
  2. Tranoudis, I., Efron, N., 2004. “Water properties of soft contact lens materials”, Contact Lens Anterior Eye, 27, 193-208.
  3. Fatt, I., Chaston, J., 1982. “Measurement of Oxygen Transmissibility and Permeability of Hydrogel Lenses and Materials”, Int. Contact Lens Clin, 9, 76-88.
  4. Refojo, M. F., Holly, F. J., Leong, F. L., 1977. “Permeability of Dissolved Oxygen through Contact Lenses I. Cellulose Acetate Butyrate”, Contact Intraocular Lens Medical J., 3, 27-33.
  5. Refojo, M. F., Leong, F. L., 1979. “Water-DissolvedOxygen Permeability Coefficients of Hydrogel Contact-Lenses and Boundary-Layer Effects”, J. Membr. Sci., 4, 415-426.
  6. Brennan, N., Efron, N., Holden, B. A., 1986. “Oxygen Permeability of Hard Gas Permeable Contact Lens Materials”, Clin. Exp. Optom., 69, 82-89.
  7. Compañ, V., Villar, M. A., Vallés, E. M., Riande, E., 1996. “Permeability and Diffusional Studies on Silicone Polymer Networks with Controlled Dangling Chains”. Polymer, 37, 101-107.
  8. Paterson, R., Doran, P. A., 1986. “Spray Technique for the Determination of Membrane Diffusion and Distribution Coefficients by the Time-Lag Method: Evaluated for Electrolyte Transport through Charged and Uncharged Membranes”, J. Membr. Sci., 26, 289-301.
  9. González-Méijome, J. M., Compañ-Moreno,V., Riande, E., 2008. “Determination of oxygen permeability in soft contact lenses using a polarographic method: estimation of relevant physiological parameters”, Industrial & Engineering Chemistry Research, 47, 10, 3619-3629.
  10. Compañ, V., Andrio, A., López-Alemany, A., Riande, E., Refojo, M. F., 2002. “Oxygen Permeability of Hydrogel Contact Lenses with Organosilicon Moieties”, Biomaterials, 23, 2767-2772.
  11. ISO International Standard 9913-1: 1996. Optics and optical instruments, Determination of Oxygen Permeability and Transmissibility by the Fatt Method. Geneva, Switzerland: International Organization for Standardization.
  12. ISO International Standard 9913-2: 2000. Optics and optical instruments, Determination of Oxygen Permeability and Transmissibility by the Coulometric Method. Geneva, Switzerland: International Organization for Standardization.
  13. ISO International Standard 18369-3: 2006. Ophthalmic optics-Contact lenses. Part 3: Measurement methods. Geneva: International Organization for Standardization.
  14. Oberndorf, D., Wilhelm, M., 2003. “Determination of oxygen permeability/transmissibility and storage of contact lenses using HPLC with reductive electrochemical detection in combination with specifically designed sampling unit”, Anal. Chem. 75, 1374-1381.
  15. Hadassah, J., Sehgal, P. K., 2006. “A novel method to measure oxygen permeability and transmissibility of contact lenses”, Clin. Exp. Optom., 89, 6, 374-380.
  16. Hale, G. M., Querry, M. R., 1973, “Optical constants of water in the 200nm to 200µm wavelength region”, Appl. Opt., 12, 555-563.
  17. Prahl, S., 2009, “Optical Absorption of Water”, Optical Spectra, http://omlc.org/index.html.
  18. Taiz, L., Zieger, E., 2015. Plant Physiology and Development, Sinauer Associates, Inc.6th edition.
Download


Paper Citation


in Harvard Style

Hung C., Huang K., Tsai H., Lin Y. and Shum P. (2017). Development of Instant Measuring Model for Oxygen Permeability and Water Content of Hydrogel Contact Lens . In Proceedings of the 5th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS, ISBN 978-989-758-223-3, pages 175-182. DOI: 10.5220/0006107301750182


in Bibtex Style

@conference{photoptics17,
author={Chih-Wei Hung and Kuo-Cheng Huang and Hsin-Yi Tsai and Yu-Hsuan Lin and Patrick Joi-Tsang Shum},
title={Development of Instant Measuring Model for Oxygen Permeability and Water Content of Hydrogel Contact Lens},
booktitle={Proceedings of the 5th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS,},
year={2017},
pages={175-182},
publisher={SciTePress},
organization={INSTICC},
doi={10.5220/0006107301750182},
isbn={978-989-758-223-3},
}


in EndNote Style

TY - CONF
JO - Proceedings of the 5th International Conference on Photonics, Optics and Laser Technology - Volume 1: PHOTOPTICS,
TI - Development of Instant Measuring Model for Oxygen Permeability and Water Content of Hydrogel Contact Lens
SN - 978-989-758-223-3
AU - Hung C.
AU - Huang K.
AU - Tsai H.
AU - Lin Y.
AU - Shum P.
PY - 2017
SP - 175
EP - 182
DO - 10.5220/0006107301750182