Dermal fibroblast and epidermal keratinocyte functionality on titania nanotube arrays

Transcutaneous implants that penetrate through the depth of the skin are used in numerous clinical applications, including prosthetics and dental implants. Favorable interactions between the implant surface and the respective skin layers are critical for the long-term success of transcutaneous implantable devices, hence, it is essential to understand the physiologic response elicited by skin-biomaterial interactions. Recent studies have shown that material surfaces that provide topographic cues at the nanoscale level may provide one possible solution to enhanced biomaterial integration, thus preventing biomaterial rejection. In this study titania nanotube arrays were fabricated using a simple anodization technique as potential interfaces for transcutaneous implantable devices. The in vitro functionality of human dermal fibroblasts and epidermal keratinocytes were evaluated on these nanotube arrays (diameter 70-90 nm, length 1-1.5 μm). Cellular functionality in terms of adhesion, proliferation, orientation, viability, cytoskeletal organization, differentiation and morphology were investigated for up to 4 days in culture using fluorescence microscope imaging, a cell viability assay, indirect immunofluorescence and scanning electron microscopy. The results reported in this study indicate increased dermal fibroblast and decreased epidermal keratinocyte adhesion, proliferation and differentiation on titania nanotube arrays.