Characterization of surface roughness of new nanophotonic soft contact lenses using lacunarity and AFM method

Aleksandra Mitrovic, Bozica Bojovic, Dragomir Stamenkovic, Dejana Popovic


The aim of this work was to develop new soft contact lens (SCL) materials which would, after recommended and existing machining processes, improve surface roughness. Nanomaterials were incorporated into commercial material for SCL (SL38) based on PHEMA, which were derived by the technology in the production lab of the company Soleko (Milan, Italy). Nanophotonic SCLs (SL38-A, SL38-B, SL38-C) were produced in the company Optix (Belgrade, Serbia) from the obtained materials. For the surface characterization of SCLs, AFM analysis and lacunarity method were performed. The results showed that SL38-B average roughness value is lower than SL38-A and SL38. The topography parameters of SL38-C were between the parameters of SL38-A and SL38-B. Lacunarity analysis of AFM images confirmed that SCLs surface state should belong to either group of adequate (slanted p-diagram) or inadequate (contorted p-diagram) roughness concerning tear film stability. Nanophotonic SCL SL38-C evince more acceptable performance consider SCL surface functional behavior compare other SCLs. The positive result of incorporating nanomaterials into basic material for SCL is better quality of the nanophotonic SCLs surfaces. On the bases of these experiments, the assumption that incorporation of fullerene derivate can play a role in the prevention of a significant increase in roughness is confirmed.


soft contact lenses, nanophotonic contact lenses, fullerenes, AFM, lacunarity

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