Preparation and Characterization of Lanthanum-Incorporated Hydroxyapatite Coatings on Titanium Substrates

Abstract

Titanium (Ti) has been widely used in clinical applications for its excellent biocompatibility and mechanical properties. However, the bioinertness of the surface of Ti has motivated researchers to improve the physicochemical and biological properties of the implants through various surface modifications, such as coatings. For this purpose, we prepared a novel bioactive material, a lanthanum-incorporated hydroxyapatite (La-HA) coating, using a dip-coating technique with a La-HA sol along with post-heat treatment. The XRD, FTIR and EDX results presented in this paper confirmed that lanthanum was successfully incorporated into the structure of HA. The La-HA coating was composed of rod-like particles which densely compacted together without microcracks. The results of the interfacial shear strength test indicated that the incorporation of lanthanum increased the bonding strength of the HA coating. The mass loss ratios under acidic conditions (pH = 5.5) suggested that the La-HA coatings have better acid resistance. The cytocompatibility of the La-HA coating was also revealed by the relative activity of alkaline phosphatase, cellular morphology and cell proliferation assay in vitro. The present study suggested that La-HA coated on Ti has promising potential for applications in the development of a new type of bioactive coating for metal implants.

Impact of B2O3 and La2O3 addition on structural, mechanical and biological properties of hydroxyapatite

“…Incorporation of 10 wt.% and 20 wt.% of B 2 O 3 in HA showed slightly toxic effect. It was reported that incorporation of La 3+ increased the proliferation rate of MC3T3-E1 cells [18,55]. For all composites, a time-dependent decrease in the cell viability was observed.…”

“…Lattice parameters of the pure HA and HA-B 2 O 3 -La 2 O 3 composites are summarized in Table 2 and the lattice values were in good agreement with dimensions of hexagonal structure of HA. Few variations in a and c axis of HA-B 2 O 3 -La 2 O 3 composites could be attributed to the dehydroxylation of the hydroxyl group which is very common for the samples calcined at high temperatures [34] or due to the partial substitution of a smaller radius Ca 2+ (0.99 Å) with a larger radius La 3+ ion (1.17Å) [18]. However, the addition of both B 2 O 3 and La 2 O 3 into HA did not result in significant changes in XRD patterns of the HA as they were still matched with the standard JCPDS file for HA.…”

“…Aside, La 2 O 3 added into the silicates resulted in higher elastic modu-lus and hardness [17]. Additionally, it improved tensile and bending strengths of HA [18]. Indeed, an infiltration of a fibrous tissue with no noteworthy sign of inflammation was observed for La-containing HA discs after implantation into the bones of a rat [18,19].…”

“…Additionally, it improved tensile and bending strengths of HA [18]. Indeed, an infiltration of a fibrous tissue with no noteworthy sign of inflammation was observed for La-containing HA discs after implantation into the bones of a rat [18,19]. Fernandez et al reported [18,20] that incorporation of 140-lanthanum into the apatite structure played a vital role in increased resistance of the hard tissues to acid dissolution.…”

Sintesis Komposit Hidroksiapatit-Lantanum Oksida (HA-La2O3) dengan Metode Hidrotermal secara In-Situ dan Ex-Situ

“…La2O3 merupakan oksida logam yang sering digunakan pada aplikasi biomedis karena tidak beracun, tidak menyebabkan iritasi, tidak menyebabkan sensitifitas terhadap sel tubuh, tidak memiliki toksisitas akut dan tidak bepotensi untuk terjadinya mutasi (Brabu et al, 2014). Pada penelitian lainnya komposit HA dengan lantanum oksida tidak beracun pada jaringan tulang dan mampu meningkatkan sifat biologisnya yang ditunjukkan rendahnya tingkat disolusi terhadap asam (Lou et al, 2015). Menurut Gerber et al, (2012) (Lim, 2015).…”