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Gaafar MS, Yakout SM, Barakat YF, Sharmoukh W. Electrophoretic deposition of hydroxyapatite/chitosan nanocomposites: the effect of dispersing agents on the coating properties. RSC Adv 2022; 12:27564-27581. [PMID: 36276043 PMCID: PMC9516373 DOI: 10.1039/d2ra03622c] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 06/11/2022] [Accepted: 09/08/2022] [Indexed: 11/23/2022] Open
Abstract
In this study, electrophoretic deposition (EPD) was used for the coating on titanium (Ti) substrate with a composite of hydroxyapatite (HA)-chitosan (CS) in the presence of dispersing agents such as polyvinyl butyral (PVB), polyethylene glycol (PEG), and triethanolamine (TEA). The materials were characterized using X-ray diffraction (XRD), transmission electron microscopy (TEM), scanning electron microscopy (SEM), zeta potential, and Fourier transform infrared (FT-IR) spectroscopy. The addition of PVB, PEG, and TEA agents improved the development of Ti coating during the EPD process. These additives increased the suspension stability and promoted the formation of uniform and compact HA/CS nanocomposite coatings on Ti substrates. The electrochemical polarization tests (e.g., potentiodynamic test) of the substrate with and without coating were investigated. Data analysis showed high corrosion resistance of Ti substrate coated with the HA/CS NP composite. The corrosion potentials displayed a shift toward positive values indicating the increase in the corrosion resistance of Ti after coating. In addition to measuring calcium ion release at various pH values and contact times at a biological pH value of 5.5, the stabilities of Ti substrates coated with HA/CS and different dispersing agents were also evaluated. Ti substrates with high anticorrosion properties may have a new potential application in biomedicine. Electrophoretic deposition was used for coating of titanium substrate with a composite of hydroxyapatite (HA)-chitosan (CS) in the presence of polyvinyl butyral (PVB), polyethylene glycol (PEG), and triethanolamine (TEA).![]()
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Affiliation(s)
- M. S. Gaafar
- Department of Chemical Engineering, Tabbin Institute for Metallurgical Studies (TIMS), PO Box: 109 Helwan, 11421 Cairo, Egypt
| | - S. M. Yakout
- Inorganic Chemistry Department, National Research Centre, Tahrir St, Dokki, Giza 12622, Egypt
| | - Y. F. Barakat
- Department of Chemical Engineering, Tabbin Institute for Metallurgical Studies (TIMS), PO Box: 109 Helwan, 11421 Cairo, Egypt
| | - W. Sharmoukh
- Inorganic Chemistry Department, National Research Centre, Tahrir St, Dokki, Giza 12622, Egypt
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2
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El-Ghannam A, Greenier M, Johnson M, Marriott I. Synthesis and characterization of porous bioactive SiC tissue engineering scaffold. J Biomed Mater Res A 2020; 108:2162-2174. [PMID: 32319213 DOI: 10.1002/jbm.a.36973] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 10/08/2019] [Revised: 03/25/2020] [Accepted: 04/04/2020] [Indexed: 12/17/2022]
Abstract
Silicon carbide (SiC) is an inert material with excellent biocompatibility properties. A major issue that limits its use as a medical device is the difficult processing technique that requires hot pressing at a temperature (>2,000o C) and pressure (1,000-2,000 atm). In the present study, we developed a protocol to synthesize a porous SiC scaffold by pressing the powder at 50 MPa and heating at 900o C/2 hr. The surface of SiC was chemically modified by NaOH to facilitate sintering and induce bioactivity. Porous discs with 51.51 ± 3.17% porosity and interconnected pores in the size range from 1 to 1,000 μm were prepared using 40% PEG. The average compressive strength and Young's modulus of the scaffolds were 1.94 ± 0.70 and 169.2 ± 0.08 MPa, respectively. FTIR analysis confirmed the formation of biomimetic hydroxyapatite layer after 2 hr of immersion in simulated body fluid. The Ca/P ratio was dependent on the concentration of the silanol groups created on the material surface. Increasing the atomic % of silicon on the SiC surface from 33.27 ± 9.53% to 45.13 ± 4.74% resulted in a 76% increase in the osteocalcin expression by MC3T3-E1 cells seeded on the material after 7 days. The cells colonized the entire thickness of the template and filled the pores with mineralized extracellular matrix after 14 days. Taken all together, the porous SiC scaffolds can serve as a bone graft for tissue reconstruction and cell delivery in trauma surgery.
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Affiliation(s)
- Ahmed El-Ghannam
- Department of Mechanical Engineering and Engineering Science, University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Madeline Greenier
- Department of Chemistry Nanoscale Science Program, University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Morgan Johnson
- Department of Biological Science, University of North Carolina at Charlotte, Charlotte, North Carolina, USA
| | - Ian Marriott
- Department of Biological Science, University of North Carolina at Charlotte, Charlotte, North Carolina, USA
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3
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Development of Novel Poly (ɛ-Caprolactone)/ Fluorine Substituted Hydroxyapatite Bilayer Coated 316L Ss for <i>In Vitro</i> Corrosion Protection. JOURNAL OF BIOMIMETICS BIOMATERIALS AND BIOMEDICAL ENGINEERING 2019. [DOI: 10.4028/www.scientific.net/jbbbe.43.84] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
A novel biocompatible fluorine substituted hydroxyapatite (F-HAp) / poly (ε-caprolactone) (PCL) bilayer coating on 316L SS with superior adhesion strength and admirable corrosion protection properties. PCL slurry was coated on 316L SS as a first layer using dip coating method followed by F-HAp coating as the second layer using electrodeposition method. The structural and functional group analysis of bilayer coatings were characterized by different analytical technique. Also, the mechanical properties of the bilayer coating showed higher adhesion strength than HAp and F-HAp coatings on 316L SS. The potentiodynamic polarization and electrochemical impedance spectroscopy results indicated that the admirable corrosion protection nature. The in vitro bioactivity test for coated 316L SS substrate was carried out by soaking it in the SBF solution, the induced apatite formation confirming the improved bioactivity of the specimen. Further, dissolution of metal ions was considerably reduced which was confirmed by inductively coupled plasma-atomic emission spectroscopy (ICP-AES). The in vitro cell–material interaction of the bilayer coating was studied with human osteosarcoma MG63 cells for cell viability at 3, 7, 14 and 21 days of incubation and good biocompatibility was observed. The obtained results show that the F-HAp/PCL bilayer coating provides effective corrosion protection and enhanced bioactivity.
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Poorraeisi M, Afshar A. Synthesizing and comparing HA–TiO2 and HA–ZrO2 nanocomposite coatings on 316 stainless steel. SN APPLIED SCIENCES 2019. [DOI: 10.1007/s42452-019-0168-2] [Citation(s) in RCA: 6] [Impact Index Per Article: 1.2] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/21/2022] Open
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5
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Adeleke SA, Bushroa AR, Sopyan I. Recent development of calcium phosphate-based coatings on titanium alloy implants. SURFACE ENGINEERING AND APPLIED ELECTROCHEMISTRY 2017. [DOI: 10.3103/s1068375517050027] [Citation(s) in RCA: 8] [Impact Index Per Article: 1.1] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/30/2022]
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6
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Hsu HC, Wu SC, Hsu SK, Liao YH, Ho WF. Effect of different post-treatments on the bioactivity of alkali-treated Ti–5Si alloy. Biomed Mater Eng 2017; 28:503-514. [DOI: 10.3233/bme-171693] [Citation(s) in RCA: 6] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/15/2022]
Affiliation(s)
- Hsueh-Chuan Hsu
- Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taiwan, ROC
| | - Shih-Ching Wu
- Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taiwan, ROC
| | - Shih-Kuang Hsu
- Department of Dental Technology and Materials Science, Central Taiwan University of Science and Technology, Taiwan, ROC
| | - Yi-Hang Liao
- Department of Materials Science and Engineering, Da-Yeh University, Taiwan, ROC
| | - Wen-Fu Ho
- Department of Chemical and Materials Engineering, National University of Kaohsiung, Kaohsiung 81148, Taiwan, ROC. E-mail:
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7
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Cytocompatibility studies of titania-doped calcium borosilicate bioactive glasses in-vitro. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 77:772-779. [DOI: 10.1016/j.msec.2017.03.245] [Citation(s) in RCA: 24] [Impact Index Per Article: 3.4] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Received: 10/23/2016] [Revised: 01/26/2017] [Accepted: 03/25/2017] [Indexed: 01/06/2023]
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8
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Eliaz N, Metoki N. Calcium Phosphate Bioceramics: A Review of Their History, Structure, Properties, Coating Technologies and Biomedical Applications. MATERIALS (BASEL, SWITZERLAND) 2017; 10:E334. [PMID: 28772697 PMCID: PMC5506916 DOI: 10.3390/ma10040334] [Citation(s) in RCA: 382] [Impact Index Per Article: 54.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Subscribe] [Scholar Register] [Received: 02/11/2017] [Revised: 03/15/2017] [Accepted: 03/22/2017] [Indexed: 02/06/2023]
Abstract
Calcium phosphate (CaP) bioceramics are widely used in the field of bone regeneration, both in orthopedics and in dentistry, due to their good biocompatibility, osseointegration and osteoconduction. The aim of this article is to review the history, structure, properties and clinical applications of these materials, whether they are in the form of bone cements, paste, scaffolds, or coatings. Major analytical techniques for characterization of CaPs, in vitro and in vivo tests, and the requirements of the US Food and Drug Administration (FDA) and international standards from CaP coatings on orthopedic and dental endosseous implants, are also summarized, along with the possible effect of sterilization on these materials. CaP coating technologies are summarized, with a focus on electrochemical processes. Theories on the formation of transient precursor phases in biomineralization, the dissolution and reprecipitation as bone of CaPs are discussed. A wide variety of CaPs are presented, from the individual phases to nano-CaP, biphasic and triphasic CaP formulations, composite CaP coatings and cements, functionally graded materials (FGMs), and antibacterial CaPs. We conclude by foreseeing the future of CaPs.
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Affiliation(s)
- Noam Eliaz
- Biomaterials and Corrosion Lab, Department of Materials Science and Engineering, Tel-Aviv University, Ramat Aviv 6997801, Israel.
| | - Noah Metoki
- Biomaterials and Corrosion Lab, Department of Materials Science and Engineering, Tel-Aviv University, Ramat Aviv 6997801, Israel.
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9
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Yan C, Hao L, Hussein A, Wei Q, Shi Y. Microstructural and surface modifications and hydroxyapatite coating of Ti-6Al-4V triply periodic minimal surface lattices fabricated by selective laser melting. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2017; 75:1515-1524. [PMID: 28415445 DOI: 10.1016/j.msec.2017.03.066] [Citation(s) in RCA: 25] [Impact Index Per Article: 3.6] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Subscribe] [Scholar Register] [Received: 09/14/2016] [Revised: 01/07/2017] [Accepted: 03/09/2017] [Indexed: 11/15/2022]
Abstract
Ti-6Al-4V Gyroid triply periodic minimal surface (TPMS) lattices were manufactured by selective laser melting (SLM). The as-built Ti-6Al-4V lattices exhibit an out-of-equilibrium microstructure with very fine α' martensitic laths. When subjected to the heat treatment of 1050°C for 4h followed by furnace cooling, the lattices show a homogenous and equilibrium lamellar α+β microstructure with less dislocation and crystallographic defects compared with the as-built α' martensite. The as-built lattices present very rough strut surfaces bonded with plenty of partially melted metal particles. The sand blasting nearly removed all the bonded metal particles, but created many tiny cracks. The HCl etching eliminated these tiny cracks, and subsequent NaOH etching resulted in many small and shallow micro-pits and develops a sodium titanate hydrogel layer on the surfaces of the lattices. When soaked in simulated body fluid (SBF), the Ti-6Al-4V TPMS lattices were covered with a compact and homogeneous biomimetic hydroxyapatite (HA) layer. This work proposes a new method for making Ti-6Al-4V TPMS lattices with a homogenous and equilibrium microstructure and biomimetic HA coating, which show both tough and bioactive characteristics and can be promising materials usable as bone substitutes.
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Affiliation(s)
- Chunze Yan
- State key Laboratory of Materials Processing and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China.
| | - Liang Hao
- China University of Giosciences, Gemmological Institute, Lumo Road 388, Wuhan 430074, China
| | - Ahmed Hussein
- College of Engineering, Mathematics and Physical Sciences, University of Exeter, Exeter EX4 4QF, Devon, United Kingdom
| | - Qingsong Wei
- State key Laboratory of Materials Processing and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China
| | - Yusheng Shi
- State key Laboratory of Materials Processing and Die & Mould Technology, Huazhong University of Science and Technology, Wuhan 430074, Hubei, China
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10
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Saleh MM, Touny AH, Al-Omair MA, Saleh MM. Biodegradable/biocompatible coated metal implants for orthopedic applications. Biomed Mater Eng 2017; 27:87-99. [PMID: 27175470 DOI: 10.3233/bme-161568] [Citation(s) in RCA: 22] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/15/2022]
Abstract
Biocompatible metals have been suggested as revolutionary biomaterials for bone-grafting therapies. Although metals and their alloys are widely and successfully used in producing biomedical implants due to their good mechanical properties and corrosion resistance, they have a lack in bioactivity. Therefore coating of the metal surface with calcium phosphates (CaP) is a benign way to achieve well bioactivity and get controlled corrosion properties. The biocompatibility and bioactivity calcium phosphates (CaP) in bone growth were guided them to biomedical treatment of bone defects and fractures. Many techniques have been used for fabrication of CaP coatings on metal substrates such as magnesium and titanium. The present review will focus on the synthesis of CaP and their relative forms using different techniques especially electrochemical techniques. The latter has always been known of its unique way of optimizing the process parameters that led to a control in the structure and characteristics of the produced materials.
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Affiliation(s)
- Mohamed M Saleh
- Kasr Al-Ainy School of Medicine, Cairo University, Cairo, Egypt
| | - A H Touny
- Department of Chemistry, Faculty of Science, Helwan University, Helwan, Cairo, Egypt.,Chemistry Department, College of Science, King Faisal University, Al-Hassa, Saudi Arabia
| | - Mohammed A Al-Omair
- Chemistry Department, College of Science, King Faisal University, Al-Hassa, Saudi Arabia
| | - M M Saleh
- Department of Chemistry, Faculty of Science, Cairo University, Cairo, Egypt.,Chemistry Department, College of Science, King Faisal University, Al-Hassa, Saudi Arabia
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11
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Share K, Westover A, Li M, Pint CL. Surface engineering of nanomaterials for improved energy storage – A review. Chem Eng Sci 2016. [DOI: 10.1016/j.ces.2016.05.034] [Citation(s) in RCA: 37] [Impact Index Per Article: 4.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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12
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Xie T, Vora A, Mulcahey PJ, Nanescu SE, Singh M, Choi DS, Huang JK, Liu CC, Sanders DP, Hahm JI. Surface Assembly Configurations and Packing Preferences of Fibrinogen Mediated by the Periodicity and Alignment Control of Block Copolymer Nanodomains. ACS NANO 2016; 10:7705-7720. [PMID: 27462904 DOI: 10.1021/acsnano.6b03071] [Citation(s) in RCA: 7] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/06/2023]
Abstract
The ability to control the specific adsorption and packing behaviors of biomedically important proteins by effectively guiding their preferred surface adsorption configuration and packing orientation on polymeric surfaces may have utility in many applications such as biomaterials, medical implants, and tissue engineering. Herein, we investigate the distinct adhesion configurations of fibrinogen (Fg) proteins and the different organization behaviors between single Fg molecules that are mediated by the changes in the periodicity and alignment of chemically alternating nanodomains in thin films of polystyrene-block-poly(methyl methacrylate) (PS-b-PMMA) block copolymer (BCP). Specifically, the adsorption characteristics of individual Fg molecules were unambiguously resolved on four different PS-b-PMMA templates of dsa PS-b-PMMA, sm PS-b-PMMA, com PS-b-PMMA, and PS-r-PMMA. By direct visualization through high resolution imaging, the distinct adsorption and packing configurations of both isolated and interacting Fg molecules were determined as a function of the BCP template-specific nanodomain periodicity, domain alignment (random versus fully aligned), and protein concentration. The three dominant Fg adsorption configurations, SP∥, SP⊥, and TP, were observed and their occurrence ratios were ascertained on each PS-b-PMMA template. During surface packing, the orientation of the protein backbone was largely governed by the periodicity and alignment of the underlying PS-b-PMMA nanodomains whose specific direction was explicitly resolved relative to the polymeric nanodomain axis. The use of PS-b-PMMA with a periodicity much smaller than (and comparable to) the length of Fg led to a Fg scaffold with the protein backbone aligned parallel (and perpendicular) to the nanodomain major axis. In addition, we have successfully created fully Fg-decorated BCP constructs analogous to two-dimensional Fg crystals in which aligned protein molecules are arranged either side-on or end-on, depending on the BCP template. Our results demonstrate that the geometry and orientation of the protein can be effectively guided during Fg self-assembly by controlling the physical dimensions and orientations of the underlying BCP templates. Finally, the biofunctionality of the BCP surface-bound Fg was assessed and the Fg/BCP construct was successfully used in the Ca-P nanoparticle nucleation/growth and microglia cell activation.
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Affiliation(s)
- Tian Xie
- Department of Chemistry, Georgetown University , 37th & O Streets NW, Washington, D.C. 20057, United States
| | - Ankit Vora
- IBM Research-Almaden , 650 Harry Rd, San Jose, California 95120, United States
| | - Patrick J Mulcahey
- Department of Chemistry, Georgetown University , 37th & O Streets NW, Washington, D.C. 20057, United States
| | - Sonia E Nanescu
- Department of Biology, Georgetown University , 37th & O Streets NW, Washington, D.C. 20057
| | - Manpreet Singh
- Department of Chemistry, Georgetown University , 37th & O Streets NW, Washington, D.C. 20057, United States
| | - Daniel S Choi
- Department of Chemistry, Georgetown University , 37th & O Streets NW, Washington, D.C. 20057, United States
| | - Jeffrey K Huang
- Department of Biology, Georgetown University , 37th & O Streets NW, Washington, D.C. 20057
| | - Chi-Chun Liu
- IBM Research-Albany Nanotech , 257 Fuller Rd, Albany, New York 12203, United States
| | - Daniel P Sanders
- IBM Research-Almaden , 650 Harry Rd, San Jose, California 95120, United States
| | - Jong-In Hahm
- Department of Chemistry, Georgetown University , 37th & O Streets NW, Washington, D.C. 20057, United States
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13
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Say Y, Aksakal B. Effects of hydroxyapatite/Zr and bioglass/Zr coatings on morphology and corrosion behaviour of Rex-734 alloy. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2016; 27:105. [PMID: 27094320 DOI: 10.1007/s10856-016-5716-3] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 02/11/2016] [Accepted: 04/09/2016] [Indexed: 06/05/2023]
Abstract
To improve corrosion resistance of metallic implant surfaces, Rex-734 alloy was coated with two different bio-ceramics; single-Hydroxyapatite (HA), double-HA/Zirconia(Zr) and double-Bioglass (BG)/Zr by using sol-gel method. Porous surface morphologies at low crack density were obtained after coating and sintering processes. Corrosion characteristics of coatings were determined by Open circuit potential and Potentiodynamic polarization measurements during corrosion tests. Hardness and adhesion strength of coating layers were measured and their surface morphologies before and after corrosion were characterized by scanning electron microscope (SEM), XRD and EDX. Through the SEM analysis, it was observed that corrosion caused degradation and sphere-like formations appeared with dimples on the coated surfaces. The coated substrates that exhibit high crack density, the corrosion was more effective by disturbing and transmitting through the coating layer, produced CrO3 and Cr3O8 oxide formation. It was found that the addition of Zr provided an increase in adhesion strength and corrosion resistance of the coatings. However, BG/Zr coatings had lower adhesion strength than the HA/Zr coatings, but showed higher corrosion resistance.
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Affiliation(s)
- Y Say
- Department of Metallurgical and Materials Engineering, Engineering Faculty, Tunceli University, 62000, Tunceli, Turkey
| | - B Aksakal
- Department of Metallurgical and Materials Engineering, Faculty of Chemical and Metallurgical and Materials Engineering, Yıldız Technical University, 34220, Istanbul, Turkey.
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14
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Kim C, Kendall MR, Miller MA, Long CL, Larson PR, Humphrey MB, Madden AS, Tas AC. Comparison of titanium soaked in 5 M NaOH or 5 M KOH solutions. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2015; 33:327-39. [PMID: 23565038 DOI: 10.1016/j.msec.2012.08.047] [Citation(s) in RCA: 26] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 01/13/2023]
Abstract
Commercially pure titanium plates/coupons and pure titanium powders were soaked for 24 h in 5 M NaOH and 5 M KOH solutions, under identical conditions, over the temperature range of 37° to 90 °C. Wettability of the surfaces of alkali-treated cpTi coupons was studied by using contact angle goniometry. cpTi coupons soaked in 5 M NaOH or 5 M KOH solutions were found to have hydrophilic surfaces. Hydrous alkali titanate nanofibers and nanotubes were identified with SEM/EDXS and grazing incidence XRD. Surface areas of Ti powders increased > 50–220 times, depending on the treatment, when soaked in the above solutions. A solution was developed to coat amorphous calcium phosphate, instead of hydroxyapatite, on Ti coupon surfaces. In vitro cell culture tests were performed with osteoblast-like cells on the alkali-treated samples.
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Affiliation(s)
- Christina Kim
- Oklahoma School of Science and Mathematics, Oklahoma City, OK 73104, USA
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15
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16
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Mehboob H, Awais M, Khalid H, Ch AA, Siddiqi SA, Rehman I. POLYMER-ASSISTED DEPOSITION OF HYDROXYAPATITE COATINGS USING ELECTROPHORETIC TECHNIQUE. BIOMEDICAL ENGINEERING-APPLICATIONS BASIS COMMUNICATIONS 2014. [DOI: 10.4015/s1016237214500732] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/07/2022]
Abstract
Hydroxyapatite (HA) finds use as powder, scaffold, paste, and coatings for orthopedic and dental applications. Plasma spraying is the most commonly used technique to coat HA on metallic implants. However, undesirable phase changes at high temperatures encourage to adopt ambient temperature deposition techniques such as dip coating, electrophoretic, and physical vapor deposition (PVD). Electrophoretic technique is being used extensively to deposit HA, however sintering is required after the deposition to enhance adhesion of coatings to the substrate. In the present work, polyethylene glycol (PEG) modified HA was deposited on 316L Stainless Steel plates using electrophoretic deposition (EPD), which improved the binding strength of the HA to the substrate with increased packing density of HA particles without the need of sintering. PEG is a biocompatible and soluble polymer that helps HA to bond well with the substrate and in addition, prevents the agglomeration and precipitation of HA. Phase identification and crystal structure of the coatings were determined using X-ray diffraction (XRD). The stability of the coatings was assessed by Fourier transform infrared spectroscopy (FTIR), whereas scanning electron microscopy (SEM) was utilized in order to investigate the morphological properties of the deposited coatings. The mechanical properties of the coatings were investigated using the indentation testing that depicted an enhanced level of adhesion of coatings to the substrate.
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Affiliation(s)
- Hassan Mehboob
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology (CIIT), Defence Road, Off Raiwind Road, Lahore, Pakistan
| | - Muhammad Awais
- Department of Industrial Engineering, Faculty of Engineering, King Abdulaziz University, Rabigh, Saudi Arabia
| | - Hamad Khalid
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology (CIIT), Defence Road, Off Raiwind Road, Lahore, Pakistan
| | - Aqif Anwar Ch
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology (CIIT), Defence Road, Off Raiwind Road, Lahore, Pakistan
| | - Saadat Anwar Siddiqi
- Interdisciplinary Research Centre in Biomedical Materials (IRCBM), COMSATS Institute of Information Technology (CIIT), Defence Road, Off Raiwind Road, Lahore, Pakistan
| | - Ihtesham Rehman
- The Kroto Research Institute, North Campus, University of Sheffield, Broad Lane, Sheffield, S3 7HQ, UK
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17
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Gopi D, Murugan N, Ramya S, Kavitha L. Electrodeposition of a porous strontium-substituted hydroxyapatite/zinc oxide duplex layer on AZ91 magnesium alloy for orthopedic applications. J Mater Chem B 2014; 2:5531-5540. [PMID: 32262186 DOI: 10.1039/c4tb00960f] [Citation(s) in RCA: 39] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
Abstract
Magnesium alloy is a potential biomedical implant because of its outstanding biodegradability and mechanical properties. But the poor corrosion resistance of AZ91 magnesium alloy in physiological solution limits its biomedical applications. In order to improve the corrosion resistance and biological performance of AZ91 magnesium alloy, we have fabricated a strontium-substituted porous hydroxyapatite (Sr-HAP)/zinc oxide (ZnO) duplex layer on AZ91 magnesium alloy by electrodeposition. The porous Sr-HAP/ZnO duplex-layer coating on AZ91 magnesium alloy was characterized by Fourier transform infrared spectroscopy, X-ray diffraction, high-resolution scanning electron microscopy and energy dispersive X-ray analysis. Also, the mechanical properties of the duplex-layer coating were evaluated using adhesion and Vickers micro-hardness tests. The effects of the duplex-layer coating on the corrosion behavior of AZ91 magnesium alloy were also investigated in simulated body fluid using electrochemical studies. The potentiodynamic polarization and electrochemical impedance spectroscopy results indicated that the corrosion resistance of AZ91 magnesium alloy was significantly improved by the duplex-layer coating. The in vitro cell-material interaction of the duplex-layer coating was observed with human osteosarcoma MG63 cells for cell viability at 1, 4 and 7 days of incubation and the coating exhibited good biocompatibility. Hence, from the obtained results we believe that the duplex-layer made of ZnO together with porous Sr-HAP on AZ91 magnesium alloy could provide effective corrosion protection and enhanced bioactivity. Thus, duplex-layer-coated AZ91 magnesium alloy can serve as a promising candidate for orthopedic applications.
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Affiliation(s)
- D Gopi
- Department of Chemistry, Periyar University, Salem 636 011, Tamilnadu, India.
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Fatehi K, Moztarzadeh F, Tahriri M, Khoshroo K, Heidari S, Sadeghi A. Biomimetic Synthesis, Characterization, and Adhesion Properties of Bone-Like Apatite on Heat and Alkaline-Treated Titanium Alloy. ACTA ACUST UNITED AC 2014. [DOI: 10.1080/15533174.2013.809747] [Citation(s) in RCA: 3] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 10/25/2022]
Affiliation(s)
- Kambiz Fatehi
- Biomaterials Group, Faculty of Biomedical Engineering (Center of Excellence), Amirkabir University of Technology, Tehran, I. R. Iran
| | - Fathollah Moztarzadeh
- Biomaterials Group, Faculty of Biomedical Engineering (Center of Excellence), Amirkabir University of Technology, Tehran, I. R. Iran
| | - Mohammadreza Tahriri
- Iranian Tissue Bank & Research Center, Tehran University of Medical Sciences, Tehran, I. R. Iran
- Dental Materials Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, I. R. Iran
| | - Kimia Khoshroo
- Dental Materials Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, I. R. Iran
| | - Soolmaz Heidari
- Dental Materials Department, School of Dentistry, Tehran University of Medical Sciences, Tehran, I. R. Iran
| | - Ali Sadeghi
- Biomaterials Group, Faculty of Biomedical Engineering (Center of Excellence), Amirkabir University of Technology, Tehran, I. R. Iran
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Ho WF, Tsou HK, Wu SC, Hsu SK, Chuang SH, Hsu HC. Effect of ethyl alcohol aging on the apatite formation of a low-modulus Ti-7.5Mo alloy treated with aqueous NaOH. BIOMATERIALS AND BIOMECHANICS IN BIOENGINEERING 2014. [DOI: 10.12989/bme.2014.1.1.051] [Citation(s) in RCA: 0] [Impact Index Per Article: 0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/22/2022]
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20
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Zakaria SM, Sharif Zein SH, Othman MR, Yang F, Jansen JA. Nanophase Hydroxyapatite as a Biomaterial in Advanced Hard Tissue Engineering: A Review. TISSUE ENGINEERING PART B-REVIEWS 2013; 19:431-41. [DOI: 10.1089/ten.teb.2012.0624] [Citation(s) in RCA: 170] [Impact Index Per Article: 15.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/12/2022]
Affiliation(s)
- Siti Maisurah Zakaria
- School of Chemical Engineering, Engineering Campus, University Sains Malaysia, Nibong Tebal, Malaysia
| | | | - Mohd. Roslee Othman
- School of Chemical Engineering, Engineering Campus, University Sains Malaysia, Nibong Tebal, Malaysia
| | - Fang Yang
- Department of Biomaterials, College of Dental Science, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
| | - John A. Jansen
- Department of Biomaterials, College of Dental Science, Radboud University Nijmegen Medical Centre, Nijmegen, The Netherlands
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21
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The electrochemical studies of the corrosion resistance behaviour of hydroxyapatite coatings on stainless steel fabricated by electrophoretic deposition. J IND ENG CHEM 2013. [DOI: 10.1016/j.jiec.2012.12.008] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.6] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/21/2022]
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22
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Corrosion protection performance of porous strontium hydroxyapatite coating on polypyrrole coated 316L stainless steel. Colloids Surf B Biointerfaces 2013; 107:130-6. [DOI: 10.1016/j.colsurfb.2013.01.065] [Citation(s) in RCA: 76] [Impact Index Per Article: 6.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 12/04/2012] [Revised: 01/22/2013] [Accepted: 01/23/2013] [Indexed: 11/20/2022]
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23
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Tanaka SI, Fukushima Y, Nakamura I, Tanaki T, Jerkiewicz G. Preparation and characterization of microporous layers on titanium by anodization in sulfuric acid with and without hydrogen charging. ACS APPLIED MATERIALS & INTERFACES 2013; 5:3340-3347. [PMID: 23488951 DOI: 10.1021/am400398d] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 06/01/2023]
Abstract
The formation of microporous oxide layers on titanium (Ti) by anodization in sulfuric acid (H2SO4) solution and the influence of prior hydrogen charging on their properties are examined using electrochemical techniques, scanning electron microscopy, grazing incident X-ray diffraction, and X-ray photoelectron spectroscopy. When Ti is anodized in 1 M aqueous H2SO4 solution at a high direct current (DC) potential (>150 V) for 1 min, a porous surface layer develops, and the process takes place with spark-discharge. Under these conditions, oxygen evolution at the Ti electrode proceeds vigorously and concurrently with the formation of anodic oxide. The oxygen gas layer adjacent to the Ti surface acts as an insulator and triggers spark-discharge; the latter stimulates the development of pores. In the absence of spark-discharge, the oxide layer has extended surface roughness but low porosity. A porous oxide layer can be prepared by applying a lower DC voltage (130 V) and without spark-discharge, but Ti requires prior hydrogen charging by cathodic polarization in 1 M aqueous H2SO4 solution. Mott-Schottky measurements indicate that the oxide layers are n-type semiconductors and that the charge carrier density in the anodic oxide layer on the hydrogen-charged Ti is lower than in the case of untreated Ti. The hydrogen charging also affects the flat band potential of the anodic oxide layers on Ti by increasing its value. The reduced charge carrier density brought about by hydrogen charging decreases the oxide layer conductivity and creates favorable conditions for its electrical breakdown that stimulates the development of pores. The porous layer on the hydrogen-charged Ti consists of anatase and rutile phases of TiO2; it has the same chemical composition as the porous layer obtained on untreated Ti. X-ray photoelectron spectroscopy measurements show that prior hydrogen charging does not affect the thickness of anodic oxides on Ti. The porous oxide layer on Ti enables the growth of hydroxyapatite, thus revealing good bioactivity in simulated body fluids.
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Affiliation(s)
- Shin-ichi Tanaka
- Department of Material Science and Engineering, Kurume National College of Technology, 1-1-1, Komorino, Kurume, Fukuoka 830-8555, Japan.
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24
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The effect of crystallographic orientation of titanium substrate on the structure and bioperformance of hydroxyapatite coatings. Colloids Surf B Biointerfaces 2013. [DOI: 10.1016/j.colsurfb.2012.10.027] [Citation(s) in RCA: 16] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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25
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Gomez Sanchez A, Schreiner W, Duffó G, Ceré S. Surface modification of titanium by anodic oxidation in phosphoric acid at low potentials. Part 1. Structure, electronic properties and thickness of the anodic films. SURF INTERFACE ANAL 2013. [DOI: 10.1002/sia.5210] [Citation(s) in RCA: 22] [Impact Index Per Article: 2.0] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/09/2022]
Affiliation(s)
- A. Gomez Sanchez
- División corrosión - INTEMA; Universidad Nacional del Mar del Plata - CONICET; Juan B. Justo 4302; 7600; Mar del Plata; Argentina
| | - W. Schreiner
- LSI - LANSEN; Departamento de Física UFPR; Curitiba; Brasil
| | | | - S. Ceré
- División corrosión - INTEMA; Universidad Nacional del Mar del Plata - CONICET; Juan B. Justo 4302; 7600; Mar del Plata; Argentina
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26
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Kim C, Kendall MR, Miller MA, Long CL, Larson PR, Humphrey MB, Madden AS, Tas AC. Comparison of titanium soaked in 5 M NaOH or 5 M KOH solutions. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2013. [PMID: 23565038 DOI: 10.1016/j.msec.2012.08.047.] [Citation(s) in RCA: 1] [Impact Index Per Article: 0.1] [Reference Citation Analysis] [Abstract] [Subscribe] [Scholar Register] [Indexed: 11/25/2022]
Abstract
Commercially pure titanium plates/coupons and pure titanium powders were soaked for 24 h in 5 M NaOH and 5 M KOH solutions, under identical conditions, over the temperature range of 37° to 90 °C. Wettability of the surfaces of alkali-treated cpTi coupons was studied by using contact angle goniometry. cpTi coupons soaked in 5 M NaOH or 5 M KOH solutions were found to have hydrophilic surfaces. Hydrous alkali titanate nanofibers and nanotubes were identified with SEM/EDXS and grazing incidence XRD. Surface areas of Ti powders increased > 50–220 times, depending on the treatment, when soaked in the above solutions. A solution was developed to coat amorphous calcium phosphate, instead of hydroxyapatite, on Ti coupon surfaces. In vitro cell culture tests were performed with osteoblast-like cells on the alkali-treated samples.
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Affiliation(s)
- Christina Kim
- Oklahoma School of Science and Mathematics, Oklahoma City, OK 73104, USA
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27
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Physical properties and cellular responses to calcium phosphate coating produced by laser rapid forming on titanium. Lasers Med Sci 2012; 29:9-17. [PMID: 23139072 DOI: 10.1007/s10103-012-1226-9] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 08/15/2012] [Accepted: 10/25/2012] [Indexed: 10/27/2022]
Abstract
In order to improve the surface bioactivity of titanium implants, CaCO₃ and CaHPO₄·2H₂O powder was used to fabricate a calcium phosphate (CaP) coating using laser rapid forming (LRF) technology. The surface characterization showed that a porous and beta-tricalcium phosphate (beta-TCP) layer with small amount of alpha-TCP was formed on commercial pure titanium (Ti). The bonding strength between the coating and the Ti substrate was above 40.17 MPa measured by the means of pull-off test. The elastic modulus and the average microhardness of the coating were 117.61 GPa and 431.2 HV₀.₁, respectively. Through the static immersion test, it was proved that the coating could not only prevent the corrosion of Ti but also promote the redeposition of beta-TCP in artificial saliva. Osteoblasts possessed good attachment performance and strong proliferation ability on the surface of LRF coating (p < 0.05) in our cell experiments. This result demonstrated that the LRF coating could improve the surface cytocompatibility of titanium. Using scanning electron microscopy observation, it was found that osteoblasts grown on LRF coating formed multiple layers in pours. The result of reverse transcription PCR analysis demonstrated that the expressions of ITGβ1 and BMP-2 were significantly (p < 0.05) upregulated on the LRF coating in a time-dependent manner, compared with uncoated Ti. These findings suggested that the LRF technology might be a promising potential treatment for fabricating CaP coatings on titanium implants.
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28
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Dorozhkin SV. Calcium orthophosphate coatings, films and layers. Prog Biomater 2012; 1:1. [PMID: 29470670 PMCID: PMC5120666 DOI: 10.1186/2194-0517-1-1] [Citation(s) in RCA: 47] [Impact Index Per Article: 3.9] [Reference Citation Analysis] [Abstract] [Key Words] [Track Full Text] [Download PDF] [Figures] [Journal Information] [Subscribe] [Scholar Register] [Received: 05/28/2012] [Accepted: 06/14/2012] [Indexed: 11/16/2022] Open
Abstract
In surgical disciplines, where bones have to be repaired, augmented or improved, bone substitutes are essential. Therefore, an interest has dramatically increased in application of synthetic bone grafts. As various interactions among cells, surrounding tissues and implanted biomaterials always occur at the interfaces, the surface properties of the implants are of the paramount importance in determining both the biological response to implants and the material response to the physiological conditions. Hence, a surface engineering is aimed to modify both the biomaterials, themselves, and biological responses through introducing desirable changes to the surface properties of the implants but still maintaining their bulk mechanical properties. To fulfill these requirements, a special class of artificial bone grafts has been introduced in 1976. It is composed of various mechanically stable (therefore, suitable for load bearing applications) biomaterials and/or bio-devices with calcium orthophosphate coatings, films and layers on their surfaces to both improve interactions with the surrounding tissues and provide an adequate bonding to bones. Many production techniques of calcium orthophosphate coatings, films and layers have been already invented and new promising techniques are continuously investigated. These specialized coatings, films and layers used to improve the surface properties of various types of artificial implants are the topic of this review.
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29
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Yang ZP, Zhang CJ, Sun YK, Ren XL. Controlled growth of calcium phosphate using phosphatidylcholine-modified porous titania as reaction compartments. Chem Eng Sci 2012. [DOI: 10.1016/j.ces.2012.05.045] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/27/2022]
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30
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Ballo AM, Xia W, Palmquist A, Lindahl C, Emanuelsson L, Lausmaa J, Engqvist H, Thomsen P. Bone tissue reactions to biomimetic ion-substituted apatite surfaces on titanium implants. J R Soc Interface 2012; 9:1615-24. [PMID: 22279159 DOI: 10.1098/rsif.2011.0808] [Citation(s) in RCA: 37] [Impact Index Per Article: 3.1] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/12/2022] Open
Abstract
The aim of this study was to evaluate the bone tissue response to strontium- and silicon-substituted apatite (Sr-HA and Si-HA) modified titanium (Ti) implants. Sr-HA, Si-HA and HA were grown on thermally oxidized Ti implants by a biomimetic process. Oxidized implants were used as controls. Surface properties, i.e. chemical composition, surface thickness, morphology/pore characteristics, crystal structure and roughness, were characterized with various analytical techniques. The implants were inserted in rat tibiae and block biopsies were prepared for histology, histomorphometry and scanning electron microscopy analysis. Histologically, new bone formed on all implant surfaces. The bone was deposited directly onto the Sr-HA and Si-HA implants without any intervening soft tissue. The statistical analysis showed significant higher amount of bone-implant contact (BIC) for the Si-doped HA modification (P = 0.030), whereas significant higher bone area (BA) for the Sr-doped HA modification (P = 0.034), when compared with the non-doped HA modification. The differences were most pronounced at the early time point. The healing time had a significant impact for both BA and BIC (P < 0.001). The present results show that biomimetically prepared Si-HA and Sr-HA on Ti implants provided bioactivity and promoted early bone formation.
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Affiliation(s)
- Ahmed M Ballo
- Department of Biomaterials, Institute for Clinical Sciences, Sahlgrenska Academy at University of Gothenburg, Gothenburg, Sweden.
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31
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KUWABARA A, HORI N, SAWADA T, HOSHI N, WATAZU A, KIMOTO K. Enhanced biological responses of a hydroxyapatite/TiO 2 hybrid structure when surface electric charge is controlled using radiofrequency sputtering. Dent Mater J 2012; 31:368-76. [DOI: 10.4012/dmj.2011-220] [Citation(s) in RCA: 18] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/23/2022]
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32
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PANG XIN, ZHITOMIRSKY IGOR. ELECTRODEPOSITION OF NANOCOMPOSITE ORGANIC–INORGANIC COATINGS FOR BIOMEDICAL APPLICATIONS. INTERNATIONAL JOURNAL OF NANOSCIENCE 2011. [DOI: 10.1142/s0219581x05003176] [Citation(s) in RCA: 29] [Impact Index Per Article: 2.2] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
Abstract
New method has been developed for the fabrication of nanocomposite hydroxyapatite (HA)-chitosan coatings. The method is based on the electrophoretic deposition (EPD) of HA nanoparticles prepared by a chemical precipitation technique, and electrochemical deposition of chitosan macromolecules. The deposit composition can be varied by the variation of HA concentration in chitosan solutions. X-ray studies revealed preferred orientation of HA nanoparticles in the nanocomposites with c-axis parallel to the coating surface. Nanocomposite coatings were obtained on Ti and Pt foils, Ti wires and gauzes. Deposition yield can be controlled by the variation of the deposition time. Coatings of various thicknesses in the range of up to 50 μm were obtained. The method enables the formation of dense, adherent and uniform deposits on substrates of complex shape. The obtained coatings provide corrosion protection of Ti and can be utilized for the fabrication of advanced biomedical implants.
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Affiliation(s)
- XIN PANG
- Department of Materials Science and Engineering, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4L7, Canada
| | - IGOR ZHITOMIRSKY
- Department of Materials Science and Engineering, McMaster University, 1280 Main Street West, Hamilton, Ontario L8S 4L7, Canada
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Polak SJ, Levengood SKL, Wheeler MB, Maki AJ, Clark SG, Johnson AJW. Analysis of the roles of microporosity and BMP-2 on multiple measures of bone regeneration and healing in calcium phosphate scaffolds. Acta Biomater 2011; 7:1760-71. [PMID: 21199692 DOI: 10.1016/j.actbio.2010.12.030] [Citation(s) in RCA: 75] [Impact Index Per Article: 5.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 09/17/2010] [Revised: 12/23/2010] [Accepted: 12/29/2010] [Indexed: 10/18/2022]
Abstract
Osteoinductive agents, such as BMP-2, are known to improve bone formation when combined with scaffolds. Microporosity (<20 μm) has also been shown to influence bone regeneration in calcium phosphate (CaP) scaffolds. However, many studies use only the term "osteoconductive" to describe the effects of BMP-2 and microporosity on bone formation, and do not assess the degree of healing that occurred. The objective of this study was to quantify the influence of BMP-2 and microporosity on bone regeneration and healing in biphasic calcium phosphate scaffolds using multiple measures including bone volume fraction, radial distribution, and specific surface area. These measures were quantitatively compared by analyzing microcomputed tomography data and used to formally define and assess healing. A custom image segmentation program was used to segment >100 samples, with 900 images each, that were implanted in porcine mandibular defects for 3, 6, 12 and 24 weeks. The assessment of healing presented in this work demonstrates the level of detail possible in evaluating scaffold-guided bone regeneration. The analysis shows that BMP-2 and microporosity accelerate healing up to 4-fold. BMP-2 and microporosity were shown to have different and complementary roles in bone formation that effect the time needed for a defect to heal.
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34
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Zhang Z, Dunn MF, Xiao TD, Tomsia AP, Saiz E. Nanostructured Hydroxyapatite Coatings for Improved Adhesion and Corrosion Resistance for Medical Implants. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-703-v7.5] [Citation(s) in RCA: 19] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
ABSTRACTHydroxyapetite (HA) coating on medical implant has been used in commercial application for several decades. The coating, commercially made by thermal spray method, functions as a intermediate layer between human tissues and the metal implant. The coating can speed up early stage healing after operation but the life span is much limited by low interfacial bond strength, which comes from the dissolution of amorphous HA in human body fluid during its service. This amorphous phase is formed in coating process under high temperature. To overcome these problems, we have developed a novel room temperature electrophoretic deposition process to fabricate nanostructured HA coating. This nanostructured HA coating significantly improved coating's bond strength up to 50-60 MPa, 2-3 times better than the thermal sprayed HA coating. The nanostructured HA coating also has corrosion resistance 50-100 times higher than the conventional HA coating. X-ray diffraction shows that all the HA coating is fully crystalline phase. It is expected that the implants with the nanostructured HA coating will have much longer service life. Other benefits derived from this process include room temperature deposition, the ability to control the coating microstructure and phases, and low cost for production.
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35
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Nancollas GH, Wu W, Tang R. The Control of Mineralization on Natural and Implant Surfaces. ACTA ACUST UNITED AC 2011. [DOI: 10.1557/proc-599-99] [Citation(s) in RCA: 5] [Impact Index Per Article: 0.4] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/13/2022]
Abstract
AbstractThe generation of minerals such as calcium phosphates on the surfaces of dental and joint replacement implants is beneficial since the facilitation of bone formation permits their fixation. In contrast, the prevention of crystallization is desired on other surfaces such as kidney and cardiac valve prostheses. A key to the development of successful biomaterials is therefore an understanding of the factors that control crystal nucleation, growth and dissolution in aqueous solution. The Constant Composition method was used to investigate the influence of factors such as solution composition, ionic strength, pH and temperature on the crystallization and dissolution of the calcium phosphates, brushite (DCPD), octacalcium phosphate (OCP), hydroxyapatite (HAP) and fluorapatite (FAP). In parallel with these studies, a contact angle method along with surface tension component theory was employed to investigate the roles of interfacial free energy in mineralization and demineralization. Values of the interfacial tensions, -4.2, 4.3, 10.4 and 18.5 mJm-2 obtained from contact angle measurements for DCPD, OCP, HAP and FAP, respectively, compare well with those calculated from dissolution kinetics experiments and provide information concerning the growth and dissolution mechanisms. The exploitation of these approaches is illustrated in studies of the coating of specific calcium phosphate phases on titanium metal and alloy surfaces and nucleation and growth of OCP on polymer surfaces modified by silanization to produce amine- and carboxylterminated end groups. In all these reactions involving the calcium phosphates, concomitant dissolution reactions are often involved. Constant Composition kinetic studies have shown that the rate of these reactions decrease markedly with time despite a sustained driving force, and eventually, the rates approach zero even though crystals remain in the undersaturated solutions. Dissolution can be reinitiated by exposing the crystals to the solutions of different undersaturations. These results suggest that dislocation sizes play a significant role in the dissolution kinetic processes.
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Boccaccini AR, Keim S, Ma R, Li Y, Zhitomirsky I. Electrophoretic deposition of biomaterials. J R Soc Interface 2010; 7 Suppl 5:S581-613. [PMID: 20504802 PMCID: PMC2952181 DOI: 10.1098/rsif.2010.0156.focus] [Citation(s) in RCA: 243] [Impact Index Per Article: 17.4] [Reference Citation Analysis] [Abstract] [Key Words] [MESH Headings] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 03/16/2010] [Accepted: 05/05/2010] [Indexed: 12/24/2022] Open
Abstract
Electrophoretic deposition (EPD) is attracting increasing attention as an effective technique for the processing of biomaterials, specifically bioactive coatings and biomedical nanostructures. The well-known advantages of EPD for the production of a wide range of microstructures and nanostructures as well as unique and complex material combinations are being exploited, starting from well-dispersed suspensions of biomaterials in particulate form (microsized and nanoscale particles, nanotubes, nanoplatelets). EPD of biological entities such as enzymes, bacteria and cells is also being investigated. The review presents a comprehensive summary and discussion of relevant recent work on EPD describing the specific application of the technique in the processing of several biomaterials, focusing on (i) conventional bioactive (inorganic) coatings, e.g. hydroxyapatite or bioactive glass coatings on orthopaedic implants, and (ii) biomedical nanostructures, including biopolymer-ceramic nanocomposites, carbon nanotube coatings, tissue engineering scaffolds, deposition of proteins and other biological entities for sensors and advanced functional coatings. It is the intention to inform the reader on how EPD has become an important tool in advanced biomaterials processing, as a convenient alternative to conventional methods, and to present the potential of the technique to manipulate and control the deposition of a range of nanomaterials of interest in the biomedical and biotechnology fields.
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Affiliation(s)
- A R Boccaccini
- Institute of Biomaterials, Department of Materials Science and Engineering, University of Erlangen-Nuremberg, Erlangen, Germany.
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37
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Nijhuis AWG, Leeuwenburgh SCG, Jansen JA. Wet-Chemical Deposition of Functional Coatings for Bone Implantology. Macromol Biosci 2010; 10:1316-29. [DOI: 10.1002/mabi.201000142] [Citation(s) in RCA: 41] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 12/28/2022]
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38
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Ho WF, Lai CH, Hsu HC, Wu SC. Surface modification of a Ti-7.5Mo alloy using NaOH treatment and Bioglass coating. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2010; 21:1479-1488. [PMID: 20069344 DOI: 10.1007/s10856-010-3990-z] [Citation(s) in RCA: 8] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 03/31/2009] [Accepted: 01/04/2010] [Indexed: 05/28/2023]
Abstract
The objective of this study was to propose a surface modification for a low-modulus Ti-7.5Mo alloy to initiate the formation of hydroxyapatite (HA) during in vitro bioactivity tests in simulated body fluid (SBF). Specimens of commercially pure titanium (c.p. Ti) and Ti-7.5Mo were initially immersed in a 15 M NaOH solution at 60 degrees C for 24 h, resulting in the formation of a porous network structure composed of sodium titanate (Na(2)Ti(5)O(11)). Afterwards, bioactive Bioglass particles were deposited on the surface of NaOH-treated c.p. Ti and Ti-7.5Mo. The specimens were then immersed in SBF at 37 degrees C for 1, 7 and 28 days, respectively. The apatite-forming ability of the NaOH-treated and Bioglass-coated Ti-7.5Mo was higher than that of the c.p. Ti under the same condition. The X-ray diffraction (XRD) and energy-dispersive X-ray spectroscopy (EDS) results indicated that the deposited amounts of calcium phosphate were much greater for the surface-treated Ti-7.5Mo than for the c.p. Ti, a finding attributable to or correlated with the higher pH value of the SBF containing surface-treated Ti-7.5Mo. Moreover, in the surface-treated Ti-7.5Mo, the pH value of the SBF approached a peak of 7.66 on the first day. A combination of NaOH treatment and subsequent Bioglass coating was successfully used to initiate in vitro HA formation in the surface of the Ti-7.5Mo alloy.
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Affiliation(s)
- Wen-Fu Ho
- Department of Materials Science and Engineering, Da-Yeh University, 168 University Road, Dacun, Changhua, 51591, Taiwan, ROC.
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Hsu YH, Turner IG, Miles AW. Mechanical properties of three different compositions of calcium phosphate bioceramic following immersion in Ringer's solution and distilled water. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:2367-2374. [PMID: 19579062 DOI: 10.1007/s10856-009-3809-y] [Citation(s) in RCA: 4] [Impact Index Per Article: 0.3] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 04/29/2009] [Accepted: 06/19/2009] [Indexed: 05/28/2023]
Abstract
Dissolution tests were carried out to compare the mechanical properties of calcium phosphate based bioceramics with different compositions, before and after ageing for various time periods in Ringer's solution (pH 7.2) or distilled water (pH 7.2 and 4.0) at 37 degrees C. The results indicate that the sample composition seems to have more of an effect on the mechanical properties than does the storage environment. No obvious decrease in mechanical properties was found after samples had been aged in the various solutions during the different time periods. This indicates that these samples could be of significant clinical interest as their good structural properties were retained.
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Affiliation(s)
- Y H Hsu
- Department of Mechanical Engineering, University of Bath, Bath, UK.
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40
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Tanaka SI, Tobimatsu H, Maruyama Y, Tanaki T, Jerkiewicz G. Preparation and characterization of microporous layers on titanium. ACS APPLIED MATERIALS & INTERFACES 2009; 1:2312-2319. [PMID: 20355867 DOI: 10.1021/am900474h] [Citation(s) in RCA: 13] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Abstract] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 05/29/2023]
Abstract
Microporous layers on titanium (Ti) are formed by chemical treatment in highly concentrated alkaline media, and their properties and growth mechanism are examined using electrochemical techniques, in situ resistometry, scanning electron microscopy (SEM), grazing-incident X-ray diffraction (GIXRD), and glow discharge optical emission spectroscopy (GD-OES). Chemical treatment in a 5 M aqueous KOH solution yields results superior to those from the same treatment in a 5 M aqueous NaOH solution, while a 3 M aqueous LiOH solution does not produce porous layers. The cation constituting the solution plays a vital role in the process. An SEM analysis reveals that the KOH solution is the most effective in forming microporosity and that the longer the treatment time, the more porous the near-surface layer. The results of GIXRD analysis show the presence of Na(2)Ti(5)O(11) and K(2)Ti(6)O(13) in the layers formed in the NaOH and KOH solutions, respectively; in the case of the LiOH solution, TiO(2) is formed. Chemical treatment in the NaOH and KOH solutions resembles a general corrosion process with the existence of local cathodic and anodic sites. The reduction reaction produces H(2), some of which becomes absorbed in the near-surface region of Ti, while the oxidation reaction produces the above-mentioned compounds and/or an oxide layer. The presence of hydrogen (H) within the solid is detected using GD-OES. The H-containing near-surface layer partially dissolves, yielding a microporous structure. The development and dissolution of the H-containing near-surface layer of Ti upon chemical treatment in the NaOH and KOH solutions are confirmed by resistometry measurements. They point to the formation of a compact passive layer on Ti upon exposure to the LiOH solution.
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Affiliation(s)
- Shin-ichi Tanaka
- Department of Materials Science and Engineering, Kurume National College of Technology, 1-1-1 Komorino, Kurume, Fukuoka 830-8555, Japan.
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41
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Das K, Bose S, Bandyopadhyay A. TiO2 nanotubes on Ti: Influence of nanoscale morphology on bone cell-materials interaction. J Biomed Mater Res A 2009; 90:225-37. [PMID: 18496867 DOI: 10.1002/jbm.a.32088] [Citation(s) in RCA: 217] [Impact Index Per Article: 14.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/06/2022]
Abstract
Ti being bioinert shows poor bone cell adhesion with an intervening fibrous capsule. Ti could be made bioactive by several methods including growing in situ TiO2 layer on Ti-surface. TiO2 nanotubes were grown on Ti surface via anodization process and the bone cell-material interactions were evaluated. Human osteoblast cell attachment and growth behavior were studied using an osteoprecursor cell line for 3, 7, and 11 days. An abundant amount of extracellular matrix (ECM) between the neighboring cells was noticed on anodized nanotube surface with filopodia extensions coming out from cells to grasp the nanoporous surface of the nanotube for anchorage. To better understand and compare cell-materials interactions, anodized nanoporous sample surfaces were etched with different patterns. Preferential cell attachment was noticed on nanotube surface compare to almost no cells in etched Ti surface. Cell adhesion with vinculin adhesive protein showed higher intensity, positive contacts on nanoporous surface and thin focal contacts on the Ti-control. Immunochemistry study with alkaline phosphatase showed enhanced osteoblastic phenotype expressions in nanoporous surface. Osteoblast proliferation was significantly higher on anodized nanotube surface. Surface properties changed with the emergence of nanoscale morphology. Higher nanometer scale roughness, low contact angle and high surface energy in nanoporous surface enhanced the osteoblast-material interactions. Mineralization study was done under simulated body fluid (SBF) with ion concentration nearly equal to human blood plasma to understand biomimetic apatite deposition behavior. Although apatite layer formation was noticed on nanotube surface, but it was nonuniform even after 21 days in SBF.
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Affiliation(s)
- Kakoli Das
- W. M. Keck Biomedical Materials Research Laboratory, School of Mechanical and Materials Engineering, Washington State University, Pullman, WA 99164, USA
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Dinda G, Shin J, Mazumder J. Pulsed laser deposition of hydroxyapatite thin films on Ti-6Al-4V: effect of heat treatment on structure and properties. Acta Biomater 2009; 5:1821-30. [PMID: 19269271 DOI: 10.1016/j.actbio.2009.01.027] [Citation(s) in RCA: 82] [Impact Index Per Article: 5.5] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 04/15/2008] [Revised: 01/20/2009] [Accepted: 01/21/2009] [Indexed: 10/21/2022]
Abstract
Hydroxyapatite (HA) is an attractive biomaterial that has been widely used as a coating for dental and orthopedic metal implants. In this work, HA coatings were deposited on Ti-6Al-4V substrates by laser ablation of HA targets with a KrF excimer laser. Deposition was performed at ambient temperature under different working pressures that varied from 10(-4) to 10(-1) torr of oxygen. The as-deposited films were amorphous. They were annealed at 290-310 degrees C in ambient air in order to restore the crystalline structure of HA. The coatings morphology, composition and structure were investigated by scanning electron microscopy, atomic force microscopy, energy-dispersive X-ray spectroscopy and X-ray diffraction techniques. Mechanical and adhesive properties were examined using nanoindentation and scratch tests, respectively. The stability of the HA coatings was tested under simulated physiological conditions. This study reveals that the combination of pulsed laser deposition and post-deposition annealing at 300 degrees C have the potential to produce pure, adherent, crystalline HA coatings, which show no dissolution in a simulated body fluid.
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Miyazaki H, Ushiroda I, Itomura D, Hirashita T, Adachi N, Ota T. Thermal expansion of hydroxyapatite between −100 °C and 50 °C. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2009. [DOI: 10.1016/j.msec.2008.12.001] [Citation(s) in RCA: 14] [Impact Index Per Article: 0.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/21/2022]
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Toworfe GK, Bhattacharyya S, Composto RJ, Adams CS, Shapiro IM, Ducheyne P. Effect of functional end groups of silane self-assembled monolayer surfaces on apatite formation, fibronectin adsorption and osteoblast cell function. J Tissue Eng Regen Med 2009; 3:26-36. [PMID: 19012271 DOI: 10.1002/term.131] [Citation(s) in RCA: 50] [Impact Index Per Article: 3.3] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/10/2022]
Abstract
Bioactive glass (BG) can directly bond to living bone without fibrous tissue encapsulation. Key mechanistic steps of BG's activity are attributed to calcium phosphate formation, surface hydroxylation and fibronectin (FN) adsorption. In the present study, self-assembled monolayers (SAMs) of alkanesilanes with different surface chemistry (OH, NH(2) and COOH) were used as a model system to mimic BG's surface activity. Calcium phosphate (Ca-P) was formed on SAMs by immersion in a solution that simulates the electrolyte content of physiological fluids. FN adsorption kinetics and monolayer coverage was determined on SAMs with or without Ca-P coating. The surface roughness was also examined on these substrates before and after FN adsorption. The effects of FN-adsorbed, Ca-P-coated SAMs on the function of MC3T3-E1 were evaluated by cell growth, expression of alkaline phosphatase activity and actin cytoskeleton formation. We demonstrate that, although the FN monolayer coverage and the root mean square (rms) roughness are similar on --OH and --COOH terminated SAMs with or without Ca-P coating, higher levels of ALP activity, more actin cytoskeleton formation and more cell growth are obtained on --OH- and --COOH-terminated SAMs with Ca-P coating. In addition, although the FN monolayer coverage is higher on Ca-P-coated --NH(2)-terminated SAMs and SiO(x) surfaces, higher levels of ALP activity and more cell growth are obtained on Ca-P-coated --OH- and --COOH-terminated SAMs. Thus, with the same Ca-P coatings, different surface functional groups have different effects on the function of osteoblastic cells. These findings represent new insights into the mechanism of bioactivity of BG and thereby may lead to designing superior constructs for bone grafting.
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Affiliation(s)
- G K Toworfe
- Center for Bioactive Materials and Tissue Engineering, University of Pennsylvania, Philadelphia, PA 19104, USA
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Wang J, de Groot K, van Blitterswijk C, de Boer J. Electrolytic deposition of lithium into calcium phosphate coatings. Dent Mater 2009; 25:353-9. [DOI: 10.1016/j.dental.2008.07.013] [Citation(s) in RCA: 22] [Impact Index Per Article: 1.5] [Reference Citation Analysis] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Received: 02/08/2008] [Accepted: 07/21/2008] [Indexed: 10/21/2022]
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Xiao X, Liu R, Tang X. Electrophoretic deposition of silicon-substituted hydroxyapatite/poly(epsilon-caprolactone) composite coatings. JOURNAL OF MATERIALS SCIENCE. MATERIALS IN MEDICINE 2009; 20:691-697. [PMID: 18949536 DOI: 10.1007/s10856-008-3619-7] [Citation(s) in RCA: 9] [Impact Index Per Article: 0.6] [Reference Citation Analysis] [Abstract] [MESH Headings] [Track Full Text] [Subscribe] [Scholar Register] [Received: 07/06/2008] [Accepted: 10/06/2008] [Indexed: 05/27/2023]
Abstract
Silicon-substituted hydroxyapatite/poly(epsilon-caprolactone) composite coatings were prepared on titanium substrate by electrophoretic deposition in n-butanol and chloroform mixture. The effect of the concentration of poly(epsilon-caprolactone) in suspension on the morphology and the microstructure of coatings were investigated, furthermore, the thermal behavior and in vitro bioactivity were also investigated. The results show that the coarse and accidented silicon-substituted hydroxyapatite/poly(epsilon-caprolactone) composite coatings were obtained by electrophoretic deposition when the concentration of poly(epsilon-caprolactone) in suspension was 6-16 g/l. The adsorption of poly(epsilon-caprolactone) on the surface of Si-HA particles hinders the electrophoretic deposition of Si-HA. The shear-testing experiments indicated that the addition of poly(epsilon-caprolactone) in suspension is in favor of improving the bonding strength of the coatings. After immersion in simulated body fluid for 8 days, silicon-substituted hydroxyapatite/poly(epsilon-caprolactone) composite coatings have the ability to induce the bone-like apatite formation.
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Affiliation(s)
- Xiufeng Xiao
- College of Chemistry and Materials Science, Fujian Normal University, Fuzhou, 350007, China
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Narayanan R, Kim SY, Kwon TY, Kim KH. Nanocrystalline hydroxyapatite coatings from ultrasonated electrolyte: preparation, characterization, and osteoblast responses. J Biomed Mater Res A 2009; 87:1053-60. [PMID: 18257064 DOI: 10.1002/jbm.a.31852] [Citation(s) in RCA: 27] [Impact Index Per Article: 1.8] [Reference Citation Analysis] [Abstract] [Track Full Text] [Journal Information] [Subscribe] [Scholar Register] [Indexed: 11/08/2022]
Abstract
An electrochemical method of producing nanograined hydroxyapatite coatings on titanium surface is reported in this article. The electrolyte contained Ca(NO(3))(2) and NH(4)H(2)PO(4) in the molar ratio of 1.67:1. The electrolyte had physiological pH and was ultrasonically agitated throughout the time of electrolysis. Coatings were deposited for 30 minutes at 10 and 15 mA/cm(2) and contained monohydroxyapatite phase whose grain sizes were 18 and 25 nm, respectively. These sizes are comparable with the grain size of bone. Small globules of hydroxyapatite covered the coating surface completely. Cell viability and total protein assay studies were carried out using SaOS-2 human osteoblast-like cell line. Of the two, the coating produced at 10 mA/cm(2) showed higher viability and protein activity and seems to be a promising material for osseointegration.
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Affiliation(s)
- R Narayanan
- Department of Dental Biomaterials, College of Dentistry and Institute for Biomaterials Research and Development, Kyungpook National University, Daegu, Korea
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Surface microstructure and cell biocompatibility of silicon-substituted hydroxyapatite coating on titanium substrate prepared by a biomimetic process. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2009. [DOI: 10.1016/j.msec.2008.07.001] [Citation(s) in RCA: 43] [Impact Index Per Article: 2.9] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/18/2022]
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49
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Javidi M, Javadpour S, Bahrololoom M, Ma J. Electrophoretic deposition of natural hydroxyapatite on medical grade 316L stainless steel. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2008. [DOI: 10.1016/j.msec.2008.04.003] [Citation(s) in RCA: 75] [Impact Index Per Article: 4.7] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 10/22/2022]
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50
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Narayanan R, Kwon TY, Kim KH. Direct nanocrystalline hydroxyapatite formation on titanium from ultrasonated electrochemical bath at physiological pH. MATERIALS SCIENCE & ENGINEERING. C, MATERIALS FOR BIOLOGICAL APPLICATIONS 2008. [DOI: 10.1016/j.msec.2007.11.009] [Citation(s) in RCA: 40] [Impact Index Per Article: 2.5] [Reference Citation Analysis] [Track Full Text] [Subscribe] [Scholar Register] [Indexed: 11/29/2022]
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