Electrochemical impedance spectroscopy of a silver-doped hydroxyapatite coating in simulated body fluid used as a corrosive agent

Abstract

Titanium is a key biomedical material due to its good biocompatibility, mechanical properties and corrosion stability, but infections at the implantation site still pose a serious threat. One approach to prevent infection is to improve the antimicrobial ability of the coating material. Silver-doped hydroxyapatite (Ag/HAP) nanoparticles were synthesized by a new modified precipitation method. The synthesized powder was used for the preparation of Ag/HAP coating on titanium by electrophoretic deposition. The coating was characterized in terms of phase composition and structure by attenuated total reflection Fourier transform infrared spectroscopy (ATR-FTIR) and X-ray diffraction (XRD); the surface morphology and chemical composition was assessed using scanning electron microscopy (SEM) and energy dispersive spectroscopy (EDS). The research focused on an evaluation of the corrosion behaviour of Ag/HAP coating in simulated body fluid (SBF) at 37°C during prolonged immersion time by electrochemical impedance spectroscopy (EIS). The silver-doped HAP coating provided good corrosion protection in SBF solution.

Titan predstavlja ključni biomedicinski materijal zahvaljujući svojoj dobroj biokompatibilnosti, mehaničkim svojstvima i korozionoj stabilnosti, ali infekcije na mestu implantiranja i dalje predstavljaju ozbiljan problem. Jedan način da se predupredi infekcija je da se poboljša antimikrobna aktivnost materijala. Srebrom dopirane nanočestice hidroksiapatita sintetisane su novom modifikovanom precipitacionom metodom. Ovako sintetisani prah je korišćen za nanošenje prevlake srebro/hidroksiapatit na titan elektoforetskim taloženjem. Fazni sastav i struktura prevlake su karakterisani spektroskopijom infracrvene svetlosti sa Furijeovom transformacijom u modu totalne refleksije i difrakcijom X-zraka. Morfologija površine i hemijski sastav ispitivani su korišćenjem skenirajuće elektronske mikroskopije i energetske disperzione spektroskopije. Cilj istraživanja je ispitivanje korozione stabilnosti prevlake srebro/hidroksiapatit u simuliranoj telesnoj tečnosti koristeći spektroskopiju elektrohemijske impedancije. Prevlaka srebro/hidroksi-apatit obezbeđuje dobru zaštitu od korozije u simuliranoj telesnoj tečnosti.