AFM in peak force mode applied to worn siloxane-hydrogel contact lenses.
The objective of this work is to apply Atomic Force Microscopy in Peak Force mode to obtain topographic characteristics (mean roughness, root-mean-square roughness, skewness and kurtosis) and mechanical characteristics (adhesion, elastic modulus) of Siloxane-Hydrogel Soft Contact Lenses (CLs) of two different materials, Lotrafilcon B of Air Optix (AO) and Asmofilcon A of PremiO (P), after use (worn CLs). Thus, the results obtained with both materials will be compared, as well as the changes produced by the wear at a nanoscopic level. The results show significant changes in the topographic and mechanical characteristics of the CLs, at a nanoscopic level, due to wear. The AO CL show values of the topographic parameters lower than those of the P CL after wear, which correlates with a better comfort qualification given to the former by the wearers. A significant correlation has also been obtained between the adhesion values found after the use of the CLs with tear quality tests, both break-up-time and Schirmer.
Universitat Politècnica de Catalunya, School of Optics and Optometry, Department of Optics and Optometry, 08222 Terrassa, Barcelona, Spain.
Clara
C
Abadías
Universitat Politècnica de Catalunya, School of Optics and Optometry, Department of Optics and Optometry, 08222 Terrassa, Barcelona, Spain.
Carme
C
Serés
Universitat Politècnica de Catalunya, School of Optics and Optometry, Department of Chemical Engineering, 08222 Terrassa, Barcelona, Spain; Institut de Bioenginyeria de Catalunya (IBEC), 08028 Barcelona, Spain. Electronic address: juan.torrent@upc.edu.
Juan
J
Torrent-Burgués
D000328:Adult; D003263:Contact Lenses, Hydrophilic; D055119:Elastic Modulus; D017743:Equipment Reuse; D005260:Female; D006801:Humans; D020100:Hydrogels / Q000737:chemistry*; D008297:Male; D008422:Materials Testing; D018625:Microscopy, Atomic Force / Q000379:methods; D012828:Silicones / Q000737:chemistry*; D012833:Siloxanes / Q000737:chemistry*; D017155:Wettability
D020100:Hydrogels; D012828:Silicones; D012833:Siloxanes; C524582:lotrafilcon B
Adhesion; Atomic force microscopy-peak force mode; Surface topography; Worn siloxane-hydrogel contact lenses; Young modulus