Abstract

Lasers are an efficient technology which can be applied for the surface treatment of polymeric biomaterials to enhance insufficient surface properties. That is, the surface chemistry and topography of biomaterials can be modulated to increase the biofunctionality of that material. By employing CO2 laser patterning and whole area processing of nylon 6,6 this paper details how the surface properties were significantly modified. Samples which had undergone whole area processing followed current theory in that the advancing contact angle, θ, with water decreased and the polar component, γp, increased upon an increase in surface roughness. For the patterned samples it was observed that θ increased and γP decreased. This did not follow current theory and can be explained by a mixed-state wetting regime. By seeding osteoblast cells onto the samples for 24 hours and 4 days the laser surface treatment gave rise to modulated cell response. For the laser whole area processing, θ and γP correlated with the observed cell count and cover density. Owed to the wetting regime, the patterned samples did not give rise to any correlative trend. As a result, CO2 laser whole area processing is more likely to allow one to predict biofunctionality prior to cell seeding. What is more, for all samples, cell differentiation was evidenced. On account of this and the modulation in cell response, it has been shown that laser surface treatment lends itself to changing the biofunctional properties of nylon 6,6.