Laser Modification of the Wettability Characteristics of a 316L Stainless Steel Bio-Metal and the Effects Thereof on Human Fibroblast Cell Response
J. Lawrence, H.R. Chew, C.K. Chong and L. Hao
This work elucidates and analyses the factors responsible for modifications to the wettability characteristics of a 316L stainless steel bio-metal following Nd:YAG laser treatment and the effects thereof on the cell response of human fibroblast cells. The specific forms of cell response analysed were the cell adhesion and cell proliferation. In this way it was possible to determine the change in the degree of biocompatibility of the 316L stainless steel after Nd:YAG laser treatment and relate this change to wettability characteristics modifications. It was found that interaction of Nd:YAG laser beam with the 316L stainless steel resulted in the wettability characteristics of the steel improving. Such improvements in the wettability characteristics of the 316L stainless steel were found to be due to: (i) modifications to the surface roughness; (ii) changes in the surface O2 content and (iii) the increase in the polar component of the surface energy. From the cell response tests it was determined that the cell proliferation and adhesion on the Nd:YAG laser treated 316L stainless steel samples were consistently less than on the untreated samples. This was found to be due entirely to the increased surface roughness effected by the Nd:YAG laser treatment. Consequently, it was possible to conclude that there was a negative correlation between wettability characteristics and human fibroblast cell response on the Nd:YAG laser treated 316L stainless steel.