Surface-modified silicone foils for intraocular implantation.

Background: Implantation of silicone materials like iris diaphragms into the eye can be complicated by cell migration and attachment. We studied polydimethylsiloxane (PDMS) foils coated with isocyanate terminated, star-shaped poly(ethylene glycol-stat-propylene glycol) (NCO-sP(EO-stat-PO)) equipped with heparin towards the inhibition of cell attachment without influencing cell viability.

Methods: Mouse fibroblasts L929 were cultured and seeded onto sterilized pieces of either uncoated NCO-sP(EO-stat-PO) or heparin-NCO-sP(EO-stat-PO) loaded foils. Polyvinylchloride (PVC) foils served as the positive control and biomembranes as the negative control. The cultured cells were examined after 24 h for cell viability and adhesion by fluorescence microscopy; morphological cell changes were documented after hemalaun staining. Cell density was measured and quantification of cell proliferation was assessed by a BrdU test; quantification of cell activity was analyzed by a WST-1 test.

Results: The fibroblasts' cell viability was excellent on all tested foils except the toxic PVC foil. NCO-sP(EO-stat-PO) coating provided significantly reduced cell activity. On heparin-loaded coatings, cells were viable and less dense but showed almost the same cell proliferation and cell activity as on the negative control. NCO-sP(EO-stat-PO) coated, heparin loaded foils proved high biocompatibility and reduced cell adhesion.

Conclusions: Both NCO-sP(EO-stat-PO)-coated foils with and without heparin seemed to be a viable implantation material for less cell migration, attachment, and reduced implant complications. Conclusive we give a recommendation for further studies on the intraocular implantation in particular for the NCO-sP(EO-stat-PO)-coated foils.