Sol-gel based calcium phosphates coating deposited on Co-Cr-Ni-Mo alloys modified by laser beam irradiation for cardiovascular devices

Abstract

Co-Cr-Ni-Mo alloy samples were irradiated by pulsed Yb: YAG laser beam under air and atmospheric pressure. Calcium phosphate coatings were deposited on the irradiated surfaces by the sol-gel method. The sol was prepared from the precursors Ca (NO3)(2)center dot 4H(2)O and H3PO4 and the modified surfaces were submitted to heat treatment conditions at 400 degrees C. The samples were characterized by the techniques of XRD, FTIR, SEM and contact angle measurements. The physicochemical and morphological analyzes showed the formation of a mixture of phases for the coating by the sol-gel method: calcium pyrophosphate and beta-TCP. Thus, through the coatings, it was possible to transform the surface of the Co-Cr-Ni-Mo alloy into a bioactive surface constituted of calcium phosphate ceramics of biological interest. The hemolysis percentage of all Co-Cr-Ni-Mo alloy models were less than 5%, and no sign of thrombogenicity was observed. In this manner, the method of surface modification by laser beam irradiation and bioactive coatings of calcium phosphates of biological interest are promising and economically feasible for use in cardiovascular devices. (C) 2019 Elsevier Ltd. All rights reserved.