Friction studies of hydrogel contact lenses using AFM: Non-crosslinked polymers of low friction at the surface

Seong Kim, Chris Marmo, Gabor A. Somorjai

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The surface of soft contact lenses made of crosslinked poly(2-hydroxyethyl methacrylate), pHEMA, has been investigated with atomic force microscopy in contact mode. The friction force and adhesive force measurements were able to differentiate the non-crosslinked pHEMA chains from the surface of the crosslinked pHEMA networks. These non-crosslinked pHEMA chains at the surface were anchored to the crosslinked pHEMA network, most likely by entanglement and their surfaces were about 2-4nm higher than the surrounding surface in a dehydrated state. In saline solution, the surface friction and adhesive force of the contact lens were significantly reduced compared to those measured for the surface-dehydrated contact lens.

Original languageEnglish (US)
Pages (from-to)3285-3294
Number of pages10
Issue number24
Publication statusPublished - Dec 15 2001


All Science Journal Classification (ASJC) codes

  • Biotechnology
  • Bioengineering
  • Biomedical Engineering

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