Preparation of bioactive coatings on the surface of bioinert polymers through an innovative auto-catalytic electroless route

The aim of this research was to develop a new methodology to obtain bioactive coatings on bioinert and biodegradable polymers that are not intrinsically bioactive. In this study, three types of materials were used as substrates: (i) high molecular weight polyethylene (HMWPE) and two different types of starch based blends (ii) starch/ethylene vinyl alcohol blends, SEVA-C, and (iii) starch/cellulose acetate blends, SCA. These materials were obtained by injection moulding and by extrusion with blowing agents in order to obtain compact/porous 3D architectures. Three types of baths were developed in order to produce the newly proposed auto-catalytic Ca-P coatings: (i) alkaline, (ii) acid, and (iii) oxidant bath. The obtained results indicated that it was possible to coat the materials surfaces with calcium phosphate (Ca-P) layer with only 60 min of immersion in the different types of auto-catalytic solutions. These innovative auto-catalytic electroless route allows for the production of an adherent bioactive film on the polymeric surfaces. Furthermore, it was possible observe by SEM/EDS the clear bioactive nature of the Ca-P coatings after different immersion periods, in a simulated body fluid (SBF).