Synthetic and Biological-Derived Hydroxyapatite Implant Coatings

A special issue of Coatings (ISSN 2079-6412). This special issue belongs to the section "Bioactive Coatings and Biointerfaces".

Deadline for manuscript submissions: closed (30 April 2023) | Viewed by 36587

Printed Edition Available!
A printed edition of this Special Issue is available here.

Special Issue Editors

National Institute for Laser, Plasma and Radiation Physics, RO-077125 Magurele, Romania
Interests: thin films deposition; biomaterials and protective coatings; characterization methods; natural origin calcium phosphates as sustainable biofunctional coatings for medical applications; biomimetic metallic implants
Special Issues, Collections and Topics in MDPI journals

E-Mail Website
Guest Editor
Marmara University, Faculty of Engineering, Bioengineering Department, Istanbul, Turkey; Nanotechnology and Biomaterial Research and Implementation Centre, Istanbul, Turkey
Interests: Pulsed laser deposition (PLD); Plasma coating; Production methods of nano-biomaterials and application areas in health sector; Drug release systems; In vitro and in vivo studies; Biomimetic production methods and applications; Electro-Spinning technique and related applications; Production methods and development of bioceramics; Production of smart nano-biopolymers to be used as carrier systems

Special Issue Information

Dear Colleagues,

We warmly invite you to submit your recent work in the field of synthesis and characterization techniques of hydroxyapatite (HA) coatings to the Special Issue “Synthetic and Biological-derived Hydroxyapatite Implant Coatings”.

In the last few decades, the field of bioactive materials for bone tissue engineering has emerged as one of the prominent approaches to tackling bone traumas and ailments, with an emphasis on the production of durable implants and bone substitutes capable of bypassing rejection complications.

HA is a well-known bioceramic which possesses a close chemical and structural resemblance to the mineral composition of bones and teeth of vertebrates. Despite their favorable bone regeneration properties, HA ceramics are very brittle, and this restricts their usage in high load-bearing applications. To overcome this drawback, HA can be applied as a coating on either metallic or polymeric implants, aiming to significantly improve the implant’s overall performance by harmoniously combining the excellent bioactivity of the ceramic with the mechanical advantages of the substrate implants.

Synthetic HA is commonly produced by several chemical routes, but recent methods to either extract or derive HA from natural sustainable resources (e.g., bones, sea-shells, various mineralogical resources) were reported. Biological-derived apatite is a carbonated HA, which contains various amounts of oligoelements and has a reduced crystallinity. Therefore, it differs from synthetic HA in terms of composition, stoichiometry, crystallinity degree, crystal size/morphology, and thus, degradation rate and overall biological performance.

Moreover, commercial thick plasma-sprayed HA coatings are susceptible to cracking and delamination and, owing to the high processing temperatures, could contain residual decomposition phases. In this respect, current research interests are rapidly advancing on two focused directions: (i) Increasing the biomimicry of HA coatings with respect to the composition and structure of bone apatite, and (ii) improving the present or even discovering alternative deposition techniques to allow for the fabrication of novel (doped) HA coatings with increased mechanical and biological performance.

In particular, the topics of interest of this Special Issue include, but are not limited to:

  • Synthetic and biological-derived HA coatings for orthopedic and dental implants;
  • Drug delivery;
  • Composite HA-based coatings;
  • Doping of synthetic and biological-derived HA coatings;
  • Alternative methods for the deposition of synthetic and biological-derived HA coatings;
  • Biofunctional assessment of synthetic and biological-derived HA coatings.

Dr. Liviu Duta
Prof. Dr. Faik Nüzhet Oktar
Guest Editors

Manuscript Submission Information

Manuscripts should be submitted online at www.mdpi.com by registering and logging in to this website. Once you are registered, click here to go to the submission form. Manuscripts can be submitted until the deadline. All submissions that pass pre-check are peer-reviewed. Accepted papers will be published continuously in the journal (as soon as accepted) and will be listed together on the special issue website. Research articles, review articles as well as short communications are invited. For planned papers, a title and short abstract (about 100 words) can be sent to the Editorial Office for announcement on this website.

Submitted manuscripts should not have been published previously, nor be under consideration for publication elsewhere (except conference proceedings papers). All manuscripts are thoroughly refereed through a single-blind peer-review process. A guide for authors and other relevant information for submission of manuscripts is available on the Instructions for Authors page. Coatings is an international peer-reviewed open access monthly journal published by MDPI.

Please visit the Instructions for Authors page before submitting a manuscript. The Article Processing Charge (APC) for publication in this open access journal is 2600 CHF (Swiss Francs). Submitted papers should be well formatted and use good English. Authors may use MDPI's English editing service prior to publication or during author revisions.

Keywords

  • synthetic and biological-derived hydroxyapatite coatings
  • adherence
  • osseointegration
  • biocompatibility
  • medical applications

Published Papers (12 papers)

Order results
Result details
Select all
Export citation of selected articles as:

Editorial

Jump to: Research

3 pages, 175 KiB  
Editorial
Synthetic and Biological-Derived Hydroxyapatite Implant Coatings
by Liviu Duta and Faik Nüzhet Oktar
Coatings 2024, 14(1), 39; https://doi.org/10.3390/coatings14010039 - 27 Dec 2023
Viewed by 715
Abstract
Bone and joint defects or diseases, coupled with edentation, pose challenging and commonly encountered clinical issues with a significant incidence in the medical domain [...] Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)

Research

Jump to: Editorial

15 pages, 36535 KiB  
Article
Bioactivity and Mechanical Properties of Hydroxyapatite on Ti6Al4V and Si(100) Surfaces by Pulsed Laser Deposition
by Salizhan Kylychbekov, Yaran Allamyradov, Zikrulloh Khuzhakulov, Inomjon Majidov, Simran Banga, Justice ben Yosef, Liviu Duta and Ali Oguz Er
Coatings 2023, 13(10), 1681; https://doi.org/10.3390/coatings13101681 - 25 Sep 2023
Cited by 1 | Viewed by 1525
Abstract
In this study, the effects of substrate temperature and ablation wavelength/mechanism on the structural, mechanical, and bioactivity properties of hydroxyapatite (HA) coatings were investigated. HA coatings were deposited on both Si(100) and Ti6Al4V surfaces. Substrate temperature varied from room temperature to 800 °C. [...] Read more.
In this study, the effects of substrate temperature and ablation wavelength/mechanism on the structural, mechanical, and bioactivity properties of hydroxyapatite (HA) coatings were investigated. HA coatings were deposited on both Si(100) and Ti6Al4V surfaces. Substrate temperature varied from room temperature to 800 °C. Depositions were performed in Ar/H2O and vacuum environments. X-ray diffraction, scanning electron microscopy, and atomic force microscopy techniques were used to analyze structural and morphological variations. The adherence of coatings to the substrates was assessed by the pull-out method. The obtained data indicated that with the temperature increase, the coatings steadily crystallized. However, temperatures above 700 °C adversely affected protein adsorption and adhesion properties. Similar trends were confirmed via pull-out testing, protein adsorption, and cell proliferation tests. The ablation mechanism was also proven to play an important role in the deposition process. Overall, this study provides further evidence that crystallinity is a vital factor in the functionality of the coatings and depends on the deposition conditions. However, all measurements directly indicated that beyond 700 °C, the morpho-structural, mechanical, and bioactivity properties degrade. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

18 pages, 4459 KiB  
Article
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
by Anca Constantina Parau, Mihaela Dinu, Cosmin Mihai Cotrut, Iulian Pana, Diana Maria Vranceanu, Lidia Ruxandra Constantin, Giuseppe Serratore, Ioana Maria Marinescu, Catalin Vitelaru, Giuseppina Ambrogio, Dennis Alexander Böhner, Annette G. Beck-Sickinger and Alina Vladescu (Dragomir)
Coatings 2023, 13(3), 591; https://doi.org/10.3390/coatings13030591 - 9 Mar 2023
Cited by 5 | Viewed by 1507
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 [...] Read more.
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. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

12 pages, 8469 KiB  
Article
Characterization of Hydroxyapatite/Chitosan Composite Coating Obtained from Crab Shells on Low-Modulus Ti–25Nb–8Sn Alloy through Hydrothermal Treatment
by Hsueh-Chuan Hsu, Shih-Ching Wu, Chien-Yu Lin and Wen-Fu Ho
Coatings 2023, 13(2), 228; https://doi.org/10.3390/coatings13020228 - 18 Jan 2023
Cited by 6 | Viewed by 1739
Abstract
In this study, hydroxyapatite/chitosan (HA/CS) composite coatings were prepared by hydrothermal treatment on the surface of low-modulus Ti–25Nb–8Sn alloy to improve the surface bioactivity of the alloy. HA, the main mineral composition of the human skeleton, has excellent bioactivity and is often used [...] Read more.
In this study, hydroxyapatite/chitosan (HA/CS) composite coatings were prepared by hydrothermal treatment on the surface of low-modulus Ti–25Nb–8Sn alloy to improve the surface bioactivity of the alloy. HA, the main mineral composition of the human skeleton, has excellent bioactivity and is often used as a surface coating on biometal implants. CS, a natural polymer with good antibacterial, hydrophilic and non-toxic characteristics, is often used as dermal regeneration templates, hemostatic agents and drug delivery systems. In this experiment, a natural crab shell was used as a raw material to prepare the HA/CS composite coating by alkali treatment and hydrothermal reaction at various temperatures. The microstructure, morphology and phase composition of the coating surfaces were analyzed by XRD, SEM, and FTIR, and the sample coated with HA/CS was soaked in simulated body fluid (SBF) to evaluate its bioactivity. The experimental results showed that the HA/CS composite coatings through hydrothermal treatment at various temperatures can be successfully fabricated on the surface of the Ti alloy. HA on the coating surface exhibited mainly spherical particles and contained A- and B-type carbonate. When the hydrothermal temperature was up to 200 °C, the spherical particles were approximately 20–40 nm. An ultrasonic vibration test was used to evaluate the adhesion of the coatings, showing that the CS exhibited significantly improved adhesion capacity to the substrate. After being soaked in SBF for 7 days, apatite was deposited on the entire surfaces of the HA/CS coatings, indicating that the coating possesses excellent bioactivity. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

25 pages, 4317 KiB  
Article
Influence of Post-Deposition Thermal Treatments on the Morpho-Structural, and Bonding Strength Characteristics of Lithium-Doped Biological-Derived Hydroxyapatite Coatings
by L. Duta, G. E. Stan, G. Popescu-Pelin, I. Zgura, M. Anastasescu and F. N. Oktar
Coatings 2022, 12(12), 1883; https://doi.org/10.3390/coatings12121883 - 4 Dec 2022
Cited by 3 | Viewed by 2340
Abstract
We report on hydroxyapatite (HA) of biological-origin doped with lithium carbonate (LiC) and lithium phosphate (LiP) coatings synthesized by Pulsed laser deposition onto Ti6Al4V substrates fabricated by the Additive manufacturing technique. A detailed comparison from the structural, morphological, chemical composition, wetting behavior and [...] Read more.
We report on hydroxyapatite (HA) of biological-origin doped with lithium carbonate (LiC) and lithium phosphate (LiP) coatings synthesized by Pulsed laser deposition onto Ti6Al4V substrates fabricated by the Additive manufacturing technique. A detailed comparison from the structural, morphological, chemical composition, wetting behavior and bonding strength standpoints of as-deposited (NTT) and post-deposition thermal-treated (TT) coatings at temperatures ranging from 400 to 700 °C (i.e., TT400–TT700), was performed. Structural investigations indicated a complete crystallization of the initially amorphous HA-based layers at temperatures in excess of 500 °C. The morphological analyses emphasized the rough appearance of the film surfaces, consisting of particulates whose dimensions increased at higher temperatures, with an emphasis on LiC coatings. AFM investigations evidenced rough surfaces, with a clear tendency to increase in corrugation with the applied temperature, in the case of LiC coatings. A hydrophobic behavior was observed for control, NTT and TT400 samples, whilst a radical shift towards hydrophilicity was demonstrated for both types of structures at higher temperatures. In the case of TT500–TT700 coatings, the pull-out adherence values increased considerably compared to control ones. Taking into consideration the obtained results, the positive influence of post-deposition thermal treatments (performed at higher temperatures) on the physical–chemical and mechanical properties of LiC and LiP coatings was indicated. Alongside these improved characteristics observed at elevated temperatures, the sustainable nature of the used BioHA materials should recommend them as viable alternatives to synthetic HA ones for bone implant applications. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Graphical abstract

15 pages, 3980 KiB  
Article
Investigation into Effect of Natural Shellac on the Bonding Strength of Magnesium Substituted Hydroxyapatite Coatings Developed on Ti6Al4V Substrates
by Ritwik Aravindakshan, Kaiprappady Kunchu Saju and Reghuraj Aruvathottil Rajan
Coatings 2021, 11(8), 933; https://doi.org/10.3390/coatings11080933 - 4 Aug 2021
Cited by 8 | Viewed by 2838
Abstract
The bioactive and biocompatible properties of hydroxyapatite (HA) promote the osseointegration process. To enhance other bio-functions of HA such as improving the antibacterial property of the implant, increasing the rate of cell proliferation, or improving tissue generation capability, HA is substituted with many [...] Read more.
The bioactive and biocompatible properties of hydroxyapatite (HA) promote the osseointegration process. To enhance other bio-functions of HA such as improving the antibacterial property of the implant, increasing the rate of cell proliferation, or improving tissue generation capability, HA is substituted with many elements such as Zn, Cl, Ba, Fe, Cu, Ag, Sr, F, Na, etc. This study reports development of Magnesium substituted HA (Mg-HA) coatings on Ti6Al4V substrates using the dip coating technique. To improve the adhesion and stability of the coating, an intermediate layer of shellac was applied between the coating and Ti6Al4V substrate. The dip coating process parameters were optimized using the Taguchi technique and it was found that dipping time of 35 s and 13% w/w of shellac concentration provided the maximum bonding strength of 12.5 MPa. The biocompatibility, dissolution, and corrosion study of the developed coating using the optimal parameters obtained were carried out in this study. An improvement in cell growth and cell proliferation was observed in the extract medium prepared from coated substrates. Release of Ca, P and Mg ions from the surface of the coated substrate into the simulated body fluid (SBF) was found to be almost constant which shows the stability of the thin film coating formed. The Mg-HA coated substrate also exhibited better corrosion resistance than the uncoated substrate. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

17 pages, 8286 KiB  
Article
Development of Arabinoxylan-Reinforced Apple Pectin/Graphene Oxide/Nano-Hydroxyapatite Based Nanocomposite Scaffolds with Controlled Release of Drug for Bone Tissue Engineering: In-Vitro Evaluation of Biocompatibility and Cytotoxicity against MC3T3-E1
by Wafa Shamsan Al-Arjan, Muhammad Umar Aslam Khan, Samina Nazir, Saiful Izwan Abd Razak and Mohammed Rafiq Abdul Kadir
Coatings 2020, 10(11), 1120; https://doi.org/10.3390/coatings10111120 - 20 Nov 2020
Cited by 38 | Viewed by 3715
Abstract
Fabrication of reinforced scaffolds to repair and regenerate defected bone is still a major challenge. Bone tissue engineering is an advanced medical strategy to restore or regenerate damaged bone. The excellent biocompatibility and osteogenesis behavior of porous scaffolds play a critical role in [...] Read more.
Fabrication of reinforced scaffolds to repair and regenerate defected bone is still a major challenge. Bone tissue engineering is an advanced medical strategy to restore or regenerate damaged bone. The excellent biocompatibility and osteogenesis behavior of porous scaffolds play a critical role in bone regeneration. In current studies, we synthesized polymeric nanocomposite material through free-radical polymerization to fabricate porous nanocomposite scaffolds by freeze drying. Functional group, surface morphology, porosity, pore size, and mechanical strength were examined through Fourier Transform Infrared Spectroscopy (FTIR), Single-Electron Microscopy (SEM), Brunauer-Emmet-Teller (BET), and Universal Testing Machine (UTM), respectively. These nanocomposites exhibit enhanced compressive strength (from 4.1 to 16.90 MPa), Young’s modulus (from 13.27 to 29.65 MPa) with well appropriate porosity and pore size (from 63.72 ± 1.9 to 45.75 ± 6.7 µm), and a foam-like morphology. The increasing amount of graphene oxide (GO) regulates the porosity and mechanical behavior of the nanocomposite scaffolds. The loading and sustained release of silver-sulfadiazine was observed to be 90.6% after 260 min. The in-vitro analysis was performed using mouse pre-osteoblast (MC3T3-E1) cell lines. The developed nanocomposite scaffolds exhibited excellent biocompatibility. Based on the results, we propose these novel nanocomposites can serve as potential future biomaterials to repair defected bone with the load-bearing application, and in bone tissue engineering. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

15 pages, 5271 KiB  
Article
Fabrication of Silver- and Zinc-Doped Hydroxyapatite Coatings for Enhancing Antimicrobial Effect
by Daniela Predoi, Simona Liliana Iconaru and Mihai Valentin Predoi
Coatings 2020, 10(9), 905; https://doi.org/10.3390/coatings10090905 - 20 Sep 2020
Cited by 32 | Viewed by 3744
Abstract
This study develops, for the first time, composite coatings based on silver and zinc doped hydroxyapatite in chitosan matrix (AgZnHApCs). The AgZnHApCs composite coatings were prepared by dip coating method. The hydroxyapatite (HAp), biocompatible material for regenerating and strengthening damaged bones were doped [...] Read more.
This study develops, for the first time, composite coatings based on silver and zinc doped hydroxyapatite in chitosan matrix (AgZnHApCs). The AgZnHApCs composite coatings were prepared by dip coating method. The hydroxyapatite (HAp), biocompatible material for regenerating and strengthening damaged bones were doped with silver and zinc ions and coated with chitosan in order to produce a uniform and homogenous coating with biocompatibility and antimicrobial properties. The stability of AgZnHApCs suspensions was evaluated by ultrasound measurements. The value of stability parameters of AgZnHApCs suspension is in good agreement with the value of bidistilled water used as reference fluid. Homogeneously dispersed solutions of AgZnHApCs were synthesized to endeavor to optimize the physico-chemical and biological characteristics of the coatings obtained at room temperature. The AgZnHApCs composite suspension and coatings were analyzed using various investigation techniques, such as X-ray diffraction (XRD), Fourier transformed infrared spectroscopy (FTIR), MTT (3-[4,5-dimethylthiazol-2-yl]-2,5-diphenylte-2H-tetrazolium bromide) assay and antimicrobial studies. The optical spectroscopy, atomic force microscopy (AFM), metallographic examination and X-ray photoelectron spectroscopy (XPS) on AgZnHApCs composite coatings were also conducted. Cell culture and MTT assays demonstrate that AgZnHApCs composite suspension and coatings have no negative effect on the cell viability and proliferation. The cell morphology was not affected in presence of AgZnHApCs composite suspension and coatings. The antimicrobial assays conducted against Staphylococcus aureus ATCC 25923, Escherichia coli ATCC 25922, and Candida albicans ATCC 90029 microbial strains revealed that both the AgZnHApCs composite suspension and coatings exhibited great antimicrobial properties. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

15 pages, 4745 KiB  
Article
Magnesium Doped Hydroxyapatite-Based Coatings Obtained by Pulsed Galvanostatic Electrochemical Deposition with Adjustable Electrochemical Behavior
by Diana Maria Vranceanu, Ionut Cornel Ionescu, Elena Ungureanu, Mihai Ovidiu Cojocaru, Alina Vladescu and Cosmin Mihai Cotrut
Coatings 2020, 10(8), 727; https://doi.org/10.3390/coatings10080727 - 24 Jul 2020
Cited by 31 | Viewed by 5290
Abstract
The aim of this study was to adapt the electrochemical behavior in synthetic body fluid (SBF) of hydroxyapatite-based coatings obtained by pulsed galvanostatic electrochemical deposition through addition of Mg in different concentrations. The coatings were obtained by electrochemical deposition in a typical three [...] Read more.
The aim of this study was to adapt the electrochemical behavior in synthetic body fluid (SBF) of hydroxyapatite-based coatings obtained by pulsed galvanostatic electrochemical deposition through addition of Mg in different concentrations. The coatings were obtained by electrochemical deposition in a typical three electrodes electrochemical cell in galvanic pulsed mode. The electrolyte was obtained by subsequently dissolving Ca(NO3)2·4H2O, NH4H2PO4, and Mg(NO3)2·6H2O in ultra-pure water and the pH value was set to 5. The morphology consists of elongated and thin ribbon-like crystals for hydroxyapatite (HAp), which after the addition of Mg became a little wider. The elemental and phase composition evidenced that HAp was successfully doped with Mg through pulsed galvanostatic electrochemical deposition. The characteristics and properties of hydroxyapatite obtained electrochemically can be controlled by adding Mg in different concentrations, thus being able to obtain materials with different properties and characteristics. In addition, the addition of Mg can lead to the control of hydroxyapatite bioactive ceramics in terms of dissolution rate. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

11 pages, 2221 KiB  
Article
Development of Apatite Nuclei Precipitated Carbon Nanotube-Polyether Ether Ketone Composite with Biological and Electrical Properties
by Chihiro Ishizaki, Takeshi Yabutsuka and Shigeomi Takai
Coatings 2020, 10(2), 191; https://doi.org/10.3390/coatings10020191 - 24 Feb 2020
Cited by 5 | Viewed by 3072
Abstract
We aimed to impart apatite-forming ability to carbon nanotube (CNT)-polyether ether ketone (PEEK) composite (CNT-PEEK). Since CNT possesses electrical conductivity, CNT-PEEK can be expected to useful not only for implant materials but also biosensing devices. First of all, in this study, CNT-PEEK was [...] Read more.
We aimed to impart apatite-forming ability to carbon nanotube (CNT)-polyether ether ketone (PEEK) composite (CNT-PEEK). Since CNT possesses electrical conductivity, CNT-PEEK can be expected to useful not only for implant materials but also biosensing devices. First of all, in this study, CNT-PEEK was treated with sulfuric acid to form fine pores on its surface. Then, the hydrophilicity of the substrate was improved by oxygen plasma treatment. After that, the substrate was promptly immersed in simulated body fluid (SBF) which was adjusted at pH 8.40, 25.0 °C (alkaline SBF) and held in an incubator set at 70.0 °C for 1 day to deposit fine particles of amorphous calcium phosphate, which we refer to as ‘apatite nuclei’. When thus-treated CNT-PEEK was immersed in SBF, its surface was spontaneously covered with hydroxyapatite within 1 day by apatite nuclei deposited in the fine pores and high apatite-forming ability was successfully demonstrated. The CNT-PEEK also showed conductivity even after the above treatment and showed smaller impedance than that of the untreated CNT-PEEK substrate. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

11 pages, 4515 KiB  
Article
Characterization of Nano-Scale Hydroxyapatite Coating Synthesized from Eggshells Through Hydrothermal Reaction on Commercially Pure Titanium
by Hsing-Ning Yu, Hsueh-Chuan Hsu, Shih-Ching Wu, Cheng-Wei Hsu, Shih-Kuang Hsu and Wen-Fu Ho
Coatings 2020, 10(2), 112; https://doi.org/10.3390/coatings10020112 - 28 Jan 2020
Cited by 21 | Viewed by 4303
Abstract
Commercially pure titanium (c.p. Ti) is often used in biomedical implants, but its surface cannot usually combine with the living bone. A coating of hydroxyapatite (HA) on the surface of titanium implants provides excellent mechanical properties and has good biological activity and biocompatibility. [...] Read more.
Commercially pure titanium (c.p. Ti) is often used in biomedical implants, but its surface cannot usually combine with the living bone. A coating of hydroxyapatite (HA) on the surface of titanium implants provides excellent mechanical properties and has good biological activity and biocompatibility. For optimal osteocompatibility, the structure, size, and composition of HA crystals should be closer to those of biological apatite. Our results show that the surface of c.p. Ti was entirely covered by rod-like HA nanoparticles after alkali treatment and subsequent hydrothermal treatment at 150 °C for 48 h. Nano-sized apatite aggregates began to nucleate on HA-coated c.p. Ti surfaces after immersion in simulated body fluid (SBF) for 6 h, while no obvious precipitation was found on the uncoated sample. Higher apatite-forming ability (bioactivity) could be acquired by the samples after HA coating. The HA coating featured bone-like nanostructure, high crystallinity, and carbonate substitution. It can be expected that HA coatings synthesized from eggshells on c.p. Ti through a hydrothermal reaction could be used in dental implant applications in the future. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Figure 1

13 pages, 4601 KiB  
Article
Lithium-Doped Biological-Derived Hydroxyapatite Coatings Sustain In Vitro Differentiation of Human Primary Mesenchymal Stem Cells to Osteoblasts
by Paula E. Florian, Liviu Duta, Valentina Grumezescu, Gianina Popescu-Pelin, Andrei C. Popescu, Faik N. Oktar, Robert W. Evans and Anca Roseanu Constantinescu
Coatings 2019, 9(12), 781; https://doi.org/10.3390/coatings9120781 (registering DOI) - 21 Nov 2019
Cited by 13 | Viewed by 3548
Abstract
This study is focused on the adhesion and differentiation of the human primary mesenchymal stem cells (hMSC) to osteoblasts lineage on biological-derived hydroxyapatite (BHA) and lithium-doped BHA (BHA:LiP) coatings synthesized by Pulsed Laser Deposition. An optimum adhesion of the cells on the surface [...] Read more.
This study is focused on the adhesion and differentiation of the human primary mesenchymal stem cells (hMSC) to osteoblasts lineage on biological-derived hydroxyapatite (BHA) and lithium-doped BHA (BHA:LiP) coatings synthesized by Pulsed Laser Deposition. An optimum adhesion of the cells on the surface of BHA:LiP coatings compared to control (uncoated Ti) was demonstrated using immunofluorescence labelling of actin and vinculin, two proteins involved in the initiation of the cell adhesion process. BHA:LiP coatings were also found to favor the differentiation of the hMSC towards an osteoblastic phenotype in the presence of osteoinductive medium, as revealed by the evaluation of osteoblast-specific markers, osteocalcin and alkaline phosphatase. Numerous nodules of mineralization secreted from osteoblast cells grown on the surface of BHA:LiP coatings and a 3D network-like organization of cells interconnected into the extracellular matrix were evidenced. These findings highlight the good biocompatibility of the BHA coatings and demonstrate that the use of lithium as a doping agent results in an enhanced osteointegration potential of the synthesized biomaterials, which might therefore represent viable candidates for future in vivo applications. Full article
(This article belongs to the Special Issue Synthetic and Biological-Derived Hydroxyapatite Implant Coatings)
Show Figures

Graphical abstract

Back to TopTop