Synthesis and characterization of sintered hydroxyapatite/lignin coatings on titanium

Abstract

To improve corrosion stability and biocompatibility of titanium surface, hydroxyapatite (Ca10(PO4)6(OH)2, HAP) has been used as coated material because it has similar chemical composition as bone tissue. Incorporation of lignin (Lig) is interesting in medical applications because it leads to thermal stability, hydrophilicity, biocompatibility and biodegrability of different materials. Bioceramic hydroxyapatite/ lignin (HAP/Lig) coatings on titanium were obtained from ethanol suspension by electrophoretic deposition method. The uniform and compact HAP/Lig coatings were deposited at constant voltage of 60 V for 45 s and sintered at 900°C in argon atmosphere. The corrosion stability of sintered HAP/Lig coatings in simulated body fluid (SBF) at 37°C was investigated by open circuit potential-time measurements and electrochemical impedance spectroscopy (EIS). The higer values of open circuit potential, as well as EIS results, indicated improved corrosion resistance and good corrosion stability of HAP/Lig coatings in simulated body fluid at 37°C.

Sinteza biokeramičkih prevlaka hidroksiapatit/lignin (HAP/Lig) na titanu vršena je elektroforetskim taloženjem iz etanolske suspenzije. Uniformne i kompaktne HAP/Lig prevlake dobijene su pri konstantnom naponu od 60 V tokom 45s. Nakon sinteze prevlake su sinterovane na 900°C u atmosferi argona. Koroziona stabilnost dobijenih sinterovanih HAP/Lig prevlaka ispitivana je u simuliranoj telesnoj tečnosti (SBF) na 37°C metodom potencijal-vreme i spektroskopijom elektrohemijske impedancije. Ispitivanja su pokazala da sinterovane HAP/Lig prevlake pokazuju dobru korozionu stabilnost u ispitivanom rastvoru.