RESUMO
In this study, a biomimetic coating in which hydroxyapatite (HAp) and collagen (Col), the major components of bone, were coated together on titanium was performed using the ECD method. The polished CP-Ti (commocially pure–titanium) disks (Ti-As), and the roughened CP-Ti disks (Ti-R) fabricated by anodic oxidation method were prepared. An electrolyte (E) was prepared by mixing Ca(NO 3 ) 2 and NH 4 H 2 PO 4 . Collagen-contaiing electrolyte (ECol) was prepared by adding collagen (Type-I) to E electrolyte. A pulse-type negative electric current of -5 mA, -10 mA, and -15 mA was applied to the titanium specimens, respectively.The temperature of electrolyte solution was maintained at 37℃. The fabricated specimens were named to Ti-As-E-5, Ti-As-E-10, Ti-As-E-15, Ti-As-ECol-5, Ti-As-ECol-10, Ti-As-ECol-15, Ti-R-E-5, Ti-R-E-10, Ti-R-E-15, Ti-R-ECol-5, Ti-R-ECol-10, and Ti-R-ECol-15, respectively. The nanorod-shaped crystallites were evenly formed on the surface of Ti-As-E groups. The length of nanorods on Ti-As-ECol groups was shorter than that on Ti-As-E groups. A low crystalline HAp structure was detected in X-ray diffraction (XRD) patterns of Ti-As-E groups. For Ti-As-ECol groups, the HAp structure was confirmed by analysis of the selected area electron diffraction (SAED) patterns obtained from a transmission electron microscope (TEM). Fourier-transform infrared spectroscopy (FT-IR) spectra of Ti-As-ECol groups showed the amide peaks assigned to collagen and related to carbonate apatite. Similarly to the Ti-As specimens, HAp crystallites were coated on Ti-R-E and Ti-R-ECol groups and their surface roughness was maintained. It is expected that the results of this study could be applied to the development of a biomimetic surface treatment method for titanium implants.
RESUMO
In this study, the hydroxyapatite (HAps) containing bovine serum albumin (BSA) were coated on titanium using the electrochemical deposition (ECD) method. Negative electric current pulses were applied to titanium specimens at 37 ℃ using a Ca- and P-containing electrolyte in which BSA was added E-BSA-10, E-BSA-15, and E-BSA-20 groups were prepared by changing the electric current to –10 mA, –15 mA, and –20 mA, respectively. As a comparative group, an E-15 specimen was prepared by applying a current of -15 mA to the specimen in Ca- and P-containing electrolyte without BSA. A coating film composed of nanosheet-shaped crystals was observed on the surface of each specimen, and the size of the nanocrystals on the BSA-containing groups was larger than that of the E-15 group. These crystals were smaller in size and higher in density as the applied current values were increased. All specimens had HAp crystalline structure. BSA-containing specimens showed a tendency of preferential growth of HAp crystals in c-axis orientation, and this tendency decreased as the applied current values were increased. In the FT-IR spectrum, amide peaks that corresponds to BSA were identified. As a result of soaking the BSA-containing group specimens in phosphate-buffered saline (PBS) for 60 hours, it was observed that the crystal structure aligned with the c-axis was disordered, and BSA was released slowly with the decomposition of HAp. This study is expected to be applied to the development of a surface treatment method for coating titanium implants with HAp containing various biological factors in the future.
RESUMO
In this study, the hydroxyapatite (HAps) containing bovine serum albumin (BSA) were coated on titanium using the electrochemical deposition (ECD) method. Negative electric current pulses were applied to titanium specimens at 37 ℃ using a Ca- and P-containing electrolyte in which BSA was added E-BSA-10, E-BSA-15, and E-BSA-20 groups were prepared by changing the electric current to –10 mA, –15 mA, and –20 mA, respectively. As a comparative group, an E-15 specimen was prepared by applying a current of -15 mA to the specimen in Ca- and P-containing electrolyte without BSA. A coating film composed of nanosheet-shaped crystals was observed on the surface of each specimen, and the size of the nanocrystals on the BSA-containing groups was larger than that of the E-15 group. These crystals were smaller in size and higher in density as the applied current values were increased. All specimens had HAp crystalline structure. BSA-containing specimens showed a tendency of preferential growth of HAp crystals in c-axis orientation, and this tendency decreased as the applied current values were increased. In the FT-IR spectrum, amide peaks that corresponds to BSA were identified. As a result of soaking the BSA-containing group specimens in phosphate-buffered saline (PBS) for 60 hours, it was observed that the crystal structure aligned with the c-axis was disordered, and BSA was released slowly with the decomposition of HAp. This study is expected to be applied to the development of a surface treatment method for coating titanium implants with HAp containing various biological factors in the future.