scholarly journals Synthesis and Characterization of Silicone Contact Lenses Based on TRIS-DMA-NVP-HEMA Hydrogels

Polymers ◽  
2019 ◽  
Vol 11 (6) ◽  
pp. 944 ◽  
Author(s):  
Nguyen-Phuong-Dung Tran ◽  
Ming-Chien Yang
Keyword(s):  
Contact Angle ◽  
Water Content ◽  
Protein Adsorption ◽  
Oxygen Permeability ◽  
Contact Lenses ◽  
Mechanical Test ◽  
Optical Transparency ◽  
Equilibrium Water Content ◽  
Silicone Hydrogel ◽  
Hydrogel Polymers

In this study, silicone-based hydrogel contact lenses were prepared by the polymerization of 3-(methacryloyloxy)propyltris(trimethylsiloxy)silane (TRIS), N,N-dimethylacrylamide (DMA), 1-vinyl-2-pyrrolidinone (NVP), and 2-hydroxyethylmethacrylate (HEMA). The properties of silicone hydrogel lenses were analyzed based on the methods such as equilibrium water content, oxygen permeability, optical transparency, contact angle, mechanical test, protein adsorption, and cell toxicity. The results showed that the TRIS content in all formulations increased the oxygen permeability and decreased the equilibrium water content, while both DMA and NVP contributed the hydrophilicity of the hydrogels. The maximum value of oxygen permeability was 74.9 barrers, corresponding to an equilibrium water content of 44.5% as well as a contact angle of 82°. Moreover, L929 fibroblasts grew on all these hydrogels, suggesting non-cytotoxicity. In general, the silicone hydrogels in this work exhibited good oxygen permeability, stiffness, and optical transparency as well as anti-protein adsorption. Hence, these silicone hydrogel polymers would be feasible for making contact lens.

Refractive index and equilibrium water content of conventional and silicone hydrogel contact lenses

2006 ◽  
Vol 26 (1) ◽  
pp. 57-64 ◽  
Author(s):  
Jose M. Gonzalez-Meijome ◽  
Madalena Lira ◽  
Antonio Lopez-Alemany ◽  
Jose B. Almeida ◽  
Manuel A. Parafita ◽  
...  
Keyword(s):  
Refractive Index ◽  
Water Content ◽  
Contact Lenses ◽  
Equilibrium Water Content ◽  
Silicone Hydrogel

scholarly journals Equivalences between refractive index and equilibrium water content of conventional and silicone hydrogel soft contact lenses from automated and manual refractometry

2006 ◽  
Vol 80B (1) ◽  
pp. 184-191 ◽  
Author(s):  
José M. González-Méijome ◽  
Antonio López-Alemany ◽  
Madalena Lira ◽  
José B. Almeida ◽  
M. Elisabete C. D. Real Oliveira ◽  
...  
Keyword(s):  
Refractive Index ◽  
Water Content ◽  
Contact Lenses ◽  
Equilibrium Water Content ◽  
Soft Contact ◽  
Silicone Hydrogel ◽  
Soft Contact Lenses

scholarly journals The influence of surface treatment on hydrophobicity, protein adsorption and microbial colonisation of silicone hydrogel contact lenses

2007 ◽  
Vol 30 (3) ◽  
pp. 183-188 ◽  
Author(s):  
Lívia Santos ◽  
Diana Rodrigues ◽  
Madalena Lira ◽  
M. Elisabete C.D. Real Oliveira ◽  
Rosário Oliveira ◽  
...  
Keyword(s):  
Surface Treatment ◽  
Protein Adsorption ◽  
Contact Lenses ◽  
Silicone Hydrogel

scholarly journals Refractive behavior changes with six months daily wear of high and low oxygen permeability hydrogel contact lenses

2006 ◽  
Vol 65 (2) ◽  
Author(s):  
W.D.H. Gillan
Keyword(s):  
Oxygen Permeability ◽  
Contact Lenses ◽  
The Other ◽  
Behavior Changes ◽  
Low Oxygen ◽  
Soft Contact ◽  
Silicone Hydrogel ◽  
Refractive State ◽  
Soft Contact Lenses ◽  
Silicone Hydrogels

Introduction: The investigation of myopia and soft contact lenses is not new. Many reports show  that  the  wearing  of  silicone  hydrogel lenses as opposed to conventional disposable hydrogel lenses results in little progression of myopia in the eyes wearing silicone hydrogels. Method: Six subjects wore a silicone hydro-gel lens on one eye while the other eye wore a habitual disposable hydrogel lens for six months of daily wear. Fifty measurements of refractive state in each eye were taken prior to the subjects wearing a silicone lens in one eye and a conven-tional hydrogel lens in the other eye. After six months of daily wear another fifty measurements of refractive state were taken for each subject. Results:  Although  there  is  no  statisti-cal  support  for  the  findings  of  this  study, comet stereo-pairs are used to show the chang-es in refractive state for each subject. Four of  the  six  subjects  showed  an  increase  in myopia in the eye wearing the silicone lens. Discussion:  The  increase  in  myopia in eyes wearing a silicone hydrogel lens is contrary  to  the  findings  of  other  studies.

scholarly journals Influence of Tear Protein Deposition on the Oxygen Permeability of Soft Contact Lenses

2017 ◽  
Vol 2017 ◽  
pp. 1-6 ◽  
Author(s):  
Se Eun Lee ◽  
So Ra Kim ◽  
Mijung Park
Keyword(s):  
Oxygen Permeability ◽  
Contact Lenses ◽  
Boundary Effect ◽  
Soft Contact ◽  
Silicone Hydrogel ◽  
Artificial Tear ◽  
Protein Deposition ◽  
Soft Contact Lenses ◽  
Tear Proteins ◽  
Tear Protein

Purpose. To investigate the effect of tear protein deposition on the change in oxygen permeability (Dk) of soft contact lenses (SCL). Methods. Three hydrogel lenses (polymacon, nelfilcon A, and etafilcon A) and two silicon hydrogel lenses (lotrafilcon A and balafilcon A) were investigated. Etafilcon A lenses were incubated in artificial tear solution for 1, 6, 12, and 48 h, whereas the other SCL were incubated for 1, 3, 7, and 14 days. Oxygen permeability was measured using the polarographic method, and lenses were stacked in four layers to correct the boundary effect. Results. The Dk of all investigated SCL was decreased by the protein deposition. Silicone hydrogel lenses showed a smaller deposition of artificial tear proteins than conventional hydrogel lenses. However, their Dk was reduced twofold than those of 3 conventional hydrogel lenses when compared at the same level of protein deposition. Despite a large amount of total deposited protein in etafilcon A lenses, their Dk was more stable than other SCL. Conclusions. From the results, it was revealed that the Dk of SCL is different from the value provided by manufacturers because of the tear protein deposition on surface and/or in pore of SCL; however, the degree of Dk change in SCL was not simply correlated with the amount of tear protein deposition. Thus, it is considered that the correlation between tear protein deposition and properties of lens materials affects Dk change.

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