Effect of Deposition Temperature on the Structure, Mechanical, Electrochemical Evaluation, Degradation Rate and Peptides Adhesion of Mg and Si-Doped Hydroxyapatite Deposited on AZ31B Alloy

Abstract

Degradable and non-degradable biomaterials are two categories that can be used to classify the existing biomaterials, being a solution for eliminating a second surgical intervention of the implant when the tissue has properly recovered. In the present paper, the effect of deposition temperature on the structure, morphology, hardness, electrochemical evaluation, degradation properties and functional peptides adhesion of Mg and Si-doped hydroxyapatite was investigated. The coatings were obtained by RF magnetron sputtering technique at room temperature (RT) and 200 °C on AZ31B alloy substrate. Results showed that an increase in deposition temperature led to an improvement in hardness and reduced modulus of about 47%. From an electrochemical point of view, a comparative assessment of corrosion resistance was made as a function of the immersion medium used, highlighting the superior behaviour revealed by the coating deposited at elevated temperature when immersed in DMEM medium (icorr~12 µA/cm2, Rcoat = 705 Ω cm2, Rct = 7624 Ω cm2). By increasing the deposition temperature up to 200 °C, the degradation rate of the coatings was slowed, more visible in the case of DMEM, which had a less aggressive effect after 14 days of immersion. Both deposition temperatures are equally suitable for further bio-inspired coating with a mussel-derived peptide, to facilitate biointegration.

In Vitro Characterization of Hydroxyapatite-Based Coatings Doped with Mg or Zn Electrochemically Deposited on Nanostructured Titanium

“…Moreover, because of its structure, HAp allows the addition of several other biocompatible elements such as Mg, Sr, Zn, and Ag, enabling other properties and characteristics of the coatings [20,[24][25][26]. Thus, doping elements, such as Ag, Zn, and Cu, are known to have a bactericidal effect [26][27][28][29][30], while Sr is known to support bone growth in osteoporotic bone [31,32], and Mg can enhance the biodegradability of HAp-based coatings [33][34][35][36].…”

Characterization of Two Types of Polylactic Acid Coating Loaded with Gentamicin Sulphate Deposed on AZ31 Alloy

“…The low corrosion resistance [9], apparently a demerit can be changed into an advantage in the field of implants, due to their biodegradability [10]. Additionally, the use of various coatings [8,11,12] and surface modifications [13] offers promising avenues for controlling and addressing this characteristic. A classification of coatings [8] as a function of the procedures of elaboration introduced mechanical, physical, chemical, and biological methods, each with numerous representatives.…”

Synthetic and Biological-Derived Hydroxyapatite Implant Coatings

“…Hence, within this Special Issue, various techniques have been introduced as alternative methods to plasma spray for coating metallic implants across diverse medical applications. These methods encompass, but are not limited to, pulsed laser deposition (PLD), magnetron sputtering (MS), electrophoretic deposition, dip-coating, hydrothermal treatment, and biomimetic coating [1,2,13,[15][16][17][18][19][20][21][22][23][24].…”