IMMOBILIZATION OF ZN SPECIES IN A POLYPYRROLE MATRIX TO PREVENT CORROSION AND MICROBIAL GROWTH ON TI-6AL-4V ALLOY FOR BIOMEDICAL APPLICATIONS

A. MARTÍNEZ; BRUGNONI, L.I.; D. FLAMINI; S. SAIDMAN

PROPRESS IN ORGANIC COATINGS

Elsevier

Año: 2020 vol. 144

0300-9440

Polypyrrole (PPy) films were potentiostatically synthesized from an aqueous solution containing sodium salicylate (NaSa) on Ti-6Al-4 V alloy. In order to develop a coating to prevent corrosion and microbial growth on thealloy, the microstructured polymer matrix was employed for the immobilization of Zn species by means of twodifferent methods. One of them involved the immobilization after the PPy electropolymerization (method 1) andthe other one during the electrosynthesis process (method 2). The antimicrobial activity against Candida albicansand Staphylococcus aureus was evaluated. Only the coating obtained by method 2 showed antibacterial activityagainst S. aureus.To verify the acceptability of the coated samples for dental implant applications, the anticorrosive propertieswere evaluated by different electrochemical techniques (open circuit potential (OCP), linear sweep voltammetry(LSV), chronoamperometry (CA)) and electrochemical impedance spectroscopy (EIS) measurements). Theelectrolyte selected to simulate the intraoral condition was artificial saliva (AS) at pH 4 containing 0.20 % NaF. Itwas found that the electrode coated with unmodified and modified PPy showed a good corrosion protectionbehavior. The active dissolution process of the alloy was suppressed. Moreover, the coatings reduce the steadystate current densities at 0.20 V (vs. saturated calomel electrode (SCE)) and decrease the release of Ti and V ions.No cracks or corrosion products were detected on the films after immersion in AS solution