In-Situ Synthesis and Characterization of Chitosan/Hydroxyapatite Nanocomposite Coatings to Improve the Bioactive Properties of Ti6Al4V Substrates

Abstract

Ti6Al4V alloy is still attracting great interest because of its application as an implant material for hard tissue repair. This research aims to produce and investigate in-situ chitosan/hydroxyapatite (CS/HA) nanocomposite coatings based on different amounts of HA (10, 50 and 60 wt.%) on alkali-treated Ti6Al4V substrate through the sol-gel process to enhance in vitro bioactivity. The influence of different contents of HA on the morphology, contact angle, roughness, adhesion strength, and in vitro bioactivity of the CS/HA coatings was studied. Results confirmed that, with increasing the HA content, the surface morphology of crack-free CS/HA coatings changed for nucleation modification and HA nanocrystals growth, and consequently, the surface roughness of the coatings increased. Furthermore, the bioactivity of the CS/HA nanocomposite coatings enhanced bone-like apatite layer formation on the material surface with increasing HA content. Moreover, CS/HA nanocomposite coatings were biocompatible and, in particular, CS/10 wt.% HA composition significantly promoted human mesenchymal stem cells (hMSCs) proliferation. In particular, these results demonstrate that the treatment strategy used during the bioprocess was able to improve in vitro properties enough to meet the clinical performance. Indeed, it is predicted that the dense and crack-free CS/HA nanocomposite coatings suggest good potential application as dental implants.

Chitosan and Hydroxyapatite Based Biomaterials to Circumvent Periprosthetic Joint Infections

“…Chitosan-HAp composites can be produced in several forms: pastes [ 120 , 121 , 122 , 123 , 124 , 125 ], coatings [ 126 , 127 , 128 , 129 , 130 ], particles [ 111 , 123 , 131 , 132 ], scaffolds [ 133 , 134 , 135 ], hydrogels [ 122 ], and films [ 136 , 137 ]. The methods employed to produce chitosan-HAp composites for orthopedic and tissue engineering applications are considerable and depend on the type of structure.…”

“…The simple mixture of HAp into a chitosan solution drives to the formation of a paste [ 120 , 121 , 122 , 124 , 125 ] that can be used for bone regeneration or to carry osteogenic inducing factors, such as bone marrow aspirate, BMP-2, or cells [ 124 ]. Chitosan-HAp coatings are mainly produced to be deposited over a titanium or other metallic substrate (simulating prosthetic materials) by spraying [ 126 ], electrophoretic deposition [ 127 ], electrochemical deposition [ 128 , 129 ], or sol-gel process [ 130 ]. Chitosan-HAp particles can be microparticles produced by spray-drying achieved [ 111 , 132 ] or nanoparticles generated by precipitation [ 123 ] or in situ hybridization [ 131 ].…”

“…Ch/HAp nanocomposite coatings were biocompatible, in particular the Ch/10 wt.% HAp composition. [130] Ch, chitosan; HAp, hydroxyapatite; nHAp, nano hydroxyapatite; Ag, silver; β-GP, beta-glycerophosphate; ormoHAp, organically modified hydroxyapatite ZnO, zinc oxide; CaO, calcium oxide; NaOH, sodium hydroxide; SEM, scanning electron microscopy; TEM, transmission electron microscope; TGA, thermogravimetric analysis; XRD, X-ray diffraction; XPS, X-ray photoelectron spectroscopy; FTIR, Fourier transformed infrared spectroscopy; EDS, energy dispersive spectroscopy; AFM, atomic force microscope; DSC, differential scanning calorimetry; NPs, nanoparticles; Ti, titanium; BMD, bone mineral density; BET, Brunauer, Emmett, and Telleru method; µCT, micro computed tomography; CCHCs, chitosan/carbonated hydroxyapatite composite coatings; CCCs, calcium carbonate coatings; CHACs, carbonated hydroxyapatite coatings; NSN, net-shape-nonwoven; 3D, tridimensional; LDH, lactate dehydrogenase; MC3T3-E1, mouse Joint replacement demands a structure with high mechanical properties, which is not the case of any of the described forms of chitosan-HAp composite. For the purpose of preventing PJI, a chitosan-HAp composite in the form of a coating or paste to cover the metallic implant would be the most appropriate.…”

Plasma Spray vs. Electrochemical Deposition: Toward a Better Osteogenic Effect of Hydroxyapatite Coatings on 3D-Printed Titanium Scaffolds

“…The mismatch of the coefficient of thermal expansion of Ti and HA results in comparatively greater shrinkage in Ti while the solution is cooled at room temperature. The residual stress that occurs during thermal spraying may induce the formation of microcracks and affect the continuity of the PSHA surface coatings ( Kotian et al, 2019 ; Ansari et al, 2020 ; Vilardell et al, 2020 ). It is noteworthy that these 2 parameters (aperture and porosity) are crucial for the 3D printing of Ti scaffolds, as they directly impact cell proliferation and differentiation.…”

Ursolic Acid Loaded-Mesoporous Hydroxylapatite/ Chitosan Therapeutic Scaffolds Regulate Bone Regeneration Ability by Promoting the M2-Type Polarization of Macrophages

“…19 Functional groups, such as ~OH and ~NH 2 in the CS structure could enhance drug release through hydrogen bond interactions. [20][21][22] Ursolic acid (UA) is a traditional medicinal plant in China that exhibits anti-cancer, anti-inflammatory, anti-virus, antibacterial, anti-diabetes, cardiovascular and anti-oxidative properties. [23][24][25][26] Most studies on UA focus on signal transduction pathways, such as transforming growth factor-β/SMAD signal transduction, mitogen-activated protein kinase and nuclear factor κB.…”