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Fast ongoing research of graphene-based nanomaterials reveals that their exceptional properties could be utized for biomedical applications, especially in tissue engineering and drug delivery. Here, we summarized the results obtained on hydroxyapatite based biocomposite coatings produced by electrophoretic deposition on titanium substrate and reinforced by nanosized graphene, as potential candidates for hard tissue implants. Brzi razvoj istraživanja nanomaterijala koji sadrže grafen otkrio je da se njihova izuzetna svojstva mogu koristiti za biomedicinske primene, posebno u inženjerstvu tkiva i kao nosači lekova. U ovom radu su prikazani rezultati istraživanja biokompozitnih prevlaka na bazi hidroksiapatita koje su dobijene elektroforetskim taloženjem na titanskom supstratu i ojačane nanočestičnim grafenom, kao potencijalnih kandidata za implante koštanog tkiva.

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.

The corrosion behaviour and thermal stability of epoxy coatings electrodeposited on modified aluminum surfaces (anodized, phosphatized and chromatized-phosphatized aluminium) were monitored during exposure to 3% NaCl solution, using electrochemical impedance spectroscopy (EIS) and thermogravimetric analysis (TGA). Better protective properties of the epoxy coatings on anodized and chromatized-phosphatized aluminum with respect to the same epoxy coatings on aluminum and phosphatized aluminum were obtained: higher values of Rp and Rct and smaller values of Cc and Cd, from EIS, and a smaller amount of absorbed water inside the coating, from TGA. On the other hand, a somewhat lower thermal stability of these coatings was obtained (smaller values of the ipdt temperature). This behavior can be explained by the less porous structure of epoxy coatings on anodized and chromatized-phosphatized aluminum, caused by a lower rate of H2 evolution and better wet ability. Postupkom kataforetskog taloženja dobijene su epoksidne zaštitne prevlake na aluminijumu i modifikovanim površinama aluminijuma (anodizirani aluminijum fosfatirani i hromatno-fosfatirani aluminijum). Za ispitivanje zaštitnih osobina ovako dobijenih epoksidnih prevlaka korišćena je spektroskopija elektrohemijske impedancije i termogravimetrijska analiza. Cilj ovog rada je bio da se objasni uticaj modifikacije supstrata na elektrohemijske karakteristike i termičku stabilnost epoksidnih prevlaka taloženih na aluminijumu.