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Surface-Functionalized Model Contact Lenses with a Bioinspired Proteoglycan 4 (PRG4)-Grafted Layer
Myrto Korogiannaki1, Michael Samsom2, Tannin A Schmidt2
1Department of Chemical Engineering , McMaster University , Hamilton , Ontario L8S 4L7 , Canada.
ACS Applied Materials & Interfaces
|August 17, 2018
Summary
Surface modification of contact lenses with Proteoglycan 4 (PRG4) improves lubrication and antifouling properties. This bioinspired approach enhances silicone hydrogel (SiHy) contact lenses for better comfort and performance.
Area of Science:
- Biomaterials Science
- Ophthalmology
- Surface Chemistry
Background:
- Contact lens wear is often discontinued due to ocular dryness and discomfort, primarily caused by poor lens hydration and increased friction.
- Proteoglycan 4 (PRG4), a natural lubricant in the eye, prevents tear evaporation and protects the ocular surface.
- Improving the interaction between the ocular surface and contact lenses is crucial for enhanced wearer comfort and lens performance.
Purpose of the Study:
- To synthesize and characterize model contact lenses surface-modified with Proteoglycan 4 (PRG4).
- To evaluate the impact of PRG4 grafting on lens properties, including antifouling, optical clarity, and biocompatibility.
- To assess the effect of PRG4 modification on surface wettability and friction against ocular tissues.
Main Methods:
- Recombinant human PRG4 (rhPRG4) was grafted onto conventional and silicone hydrogel (SiHy) model contact lenses using N, N'-carbonyldiimidazole linking chemistry.
- Grafting was confirmed using Fourier transform infrared spectroscopy-attenuated total reflectance, X-ray photoelectron spectroscopy, and radioactive labeling.
- Antifouling properties, optical transparency, cytotoxicity, surface wettability, and kinetic friction were evaluated.
Main Results:
- Surface immobilization of rhPRG4 resulted in improved antifouling properties for both conventional and SiHy model lenses.
- Optical transparency and cytotoxicity assays showed no adverse effects on human corneal epithelial cells.
- Only rhPRG4-grafted SiHy lenses demonstrated a reduced contact angle and kinetic friction coefficient compared to unmodified surfaces.
Conclusions:
- Clinical-grade rhPRG4 can be effectively grafted onto SiHy contact lenses, enhancing their surface properties.
- rhPRG4-modified SiHy lenses show potential for improved ocular surface lubrication and reduced friction.
- This bioinspired approach offers a promising strategy for developing next-generation contact lenses with superior comfort and performance.
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