Investigation of the in vitro corrosion behavior and biocompatibility of niobium (Nb)-reinforced hydroxyapatite (HA) coating on CoCr alloy for medical implants

Biodegradable metals have been under significant research as promising alternatives to the currently in-use nonbiodegradable materials in the field of supportive medical implants. In this scope, magnesium and its alloys were widely investigated due to their superior biocompatibility over other metals. Most of the research effort in the literature has been focused on assuring the biocompatibility, improving mechanical properties, and tailoring the corrosion rate of magnesium-based implants. Furthermore, considerable research was done to develop numerical models towards an inexpensive and fast designing tools capable of simulating the degradation/corrosion behavior of magnesium-based implants. Due to the complexity of the degradation process and the various factors that can be involved, several hypotheses were introduced to provide a realistic simulation of the corrosion behavior in vitro and in vivo. A review of the current literature hypothesis and different modeling constitutive equations for modeling the corrosion of magnesium alloys along with a summary of the supplementary experimental methods is provided in this paper.

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ELECTROHYDRODYNAMIC PROCESSING OF CALCIUM PHOSPHATES: COATING AND PATTERNING FOR MEDICAL IMPLANTS

Nano LIFE ◽

10.1142/s1793984411000426 ◽

2012 ◽

Vol 02 (01) ◽

pp. 1250008 ◽

Cited By ~ 3

Author(s):

GILLIAN MUNIR ◽

JIE HUANG ◽

MOHAN EDIRISINGHE ◽

RAFIQUE NANGREJO ◽

WILLIAM BONFIELD

Keyword(s):

Surface Topography ◽

Cellular Response ◽

Cell Attachment ◽

Calcium Phosphates ◽

Life Time ◽

Medical Implants ◽

Osteoblast Cells ◽

Ha Coating ◽

Electrohydrodynamic Atomization

Hydroxyapatite (HA)-coated metallic prostheses, which combine the osteoconductivity of HA and high strength of metallic alloys, have been increasingly the choice of joint replacement prostheses by surgeons as the general population lives longer. Surface modification of metallic implant surfaces is one of the key focal points to implantation technology. In addition to material chemistry, surface topography has been found to positively impact cellular response and is able to enhance the life time of the implant. Recently, a new technique, template-assisted electrohydrodynamic atomization (TAEA) spraying, developed using the principles of electrohydrodynamic atomization spraying, which is an electrically driven jet-based deposition method, is of considerable interest in surface topography formation. The process offers the attractive advantages of compatibility with micro-fabrication technology and versatility in pattern specification for advanced implant designs. This technology incorporates nanosized calcium phosphate to mimic the size and chemical composition of bone mineral in a micrometer-dimension pattern configuration to guide cellular responses. In vitro studies showed that both pillar and track nano Silicon-substituted HA (SiHA) patterns were able to encourage the attachment and growth of osteoblast cells, the track patterns provided the favourite surface for the initial cell attachment while a fast cell proliferation rate was found on the pillar pattern from day 1 to day 5 in comparison with that of a SiHA-coated surface. The alignment of actin cytoskeleton of osteoblast cells matched the orientation of the entire cell. The shear peel strength of the patterned interlocking nano-HA coating was found to be at least an order of magnitude higher than the conventional HA coating. Therefore, TAEA offers great potential for producing new coatings with a tailored surface topography, on both the micro- and nano-scale in a more cost effective way to enhance the performance of medical implants.

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Biodegradable Metallic Materials for Temporary Medical Implants

Materials Science Forum ◽

10.4028/www.scientific.net/msf.891.395 ◽

2017 ◽

Vol 891 ◽

pp. 395-399 ◽

Cited By ~ 1

Author(s):

Dalibor Vojtěch ◽

Jiří Kubásek ◽

Jaroslav Čapek ◽

Iva Pospíšilová

Keyword(s):

Blood Vessels ◽

Corrosion Behavior ◽

Mechanical Performance ◽

Metallic Materials ◽

Medical Implants ◽

Advantages And Disadvantages ◽

Fe Alloys

Biodegradable Mg, Zn and Fe alloys are currently studied as prospective biomaterials for temporary medical implants like stents for repairing damaged blood vessels and devices (screws and plates) for fixing fractured bones. In the present paper, novel Mg-, Zn- and Fe-biodegradable alloys are proposed. Advantages and disadvantages of the three kinds of alloys are demonstrated regarding the mechanical performance, in vitro corrosion behavior and biocompatibility.

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Sem Studies of Co-Cr-Mo Surgical Implant Alloy Corrosion Behavior

Proceedings, annual meeting, Electron Microscopy Society of America ◽

10.1017/s0424820100055448 ◽

1982 ◽

Vol 40 ◽

pp. 520-521

Author(s):

Ann Chidester Van Orden ◽

John L. Chidester ◽

Anna C. Fraker ◽

Pei Sung

Keyword(s):

Electron Microscopy ◽

Corrosion Behavior ◽

Anodic Polarization ◽

Saline Solution ◽

Saturated Calomel Electrode ◽

Physiological Saline ◽

X Ray ◽

Physiological Saline Solution ◽

Scanning Electron

The influence of small variations in the composition on the corrosion behavior of Co-Cr-Mo alloys has been studied using scanning electron microscopy (SEM), energy dispersive x-ray analysis (EDX), and electrochemical measurements. SEM and EDX data were correlated with data from in vitro corrosion measurements involving repassivation and also potentiostatic anodic polarization measurements. Specimens studied included the four alloys shown in Table 1. Corrosion tests were conducted in Hanks' physiological saline solution which has a pH of 7.4 and was held at a temperature of 37°C. Specimens were mechanically polished to a surface finish with 0.05 µm A1203, then exposed to the solution and anodically polarized at a rate of 0.006 v/min. All voltages were measured vs. the saturated calomel electrode (s.c.e.).. Specimens had breakdown potentials near 0.47V vs. s.c.e.

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In Vitro Assessment of Hydroxyapatite Coating on the Surface of Additive Manufactured Ti6Al4V Scaffolds

Materials Science Forum ◽

10.4028/www.scientific.net/msf.879.2444 ◽

2016 ◽

Vol 879 ◽

pp. 2444-2449 ◽

Cited By ~ 1

Author(s):

Ekaterina Chudinova ◽

Maria Surmeneva ◽

Andrey Koptioug ◽

Irina V. Savintseva ◽

Irina Selezneva ◽

...

Keyword(s):

Stem Cells ◽

Mesenchymal Stem Cells ◽

Human Mesenchymal Stem Cells ◽

Nanocrystalline Structure ◽

X Ray Diffraction ◽

Ha Coating ◽

Magnetron Sputter Deposition ◽

In Vitro Assessment ◽

Average Size

Custom orthopedic and dental implants may be fabricated by additive manufacturing (AM), for example using electron beam melting technology. This study is focused on the modification of the surface of Ti6Al4V alloy coin-like scaffolds fabricated via AM technology (EBM®) by radio frequency (RF) magnetron sputter deposition of hydroxyapatite (HA) coating. The scaffolds with HA coating were characterized by Scanning Electron microscopy, X-ray diffraction. HA coating showed a nanocrystalline structure with the crystallites of an average size of 32±9 nm. The ability of the surface to support adhesion and the proliferation of human mesenchymal stem cells was studied using biological short-term tests in vitro. In according to in vitro assessment, thin HA coating stimulated the attachment and proliferation of cells. Human mesenchymal stem cells cultured on the HA-coated scaffold also formed mineralized nodules.

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Heparin-mediated antibiotic delivery from an electrochemically-aligned collagen sheet

Bio-Medical Materials and Engineering ◽

10.3233/bme-201133 ◽

2021 ◽

pp. 1-12

Author(s):

Olivia T. Cheng ◽

Andrew P. Stein ◽

Eric Babajanian ◽

Kathryn R. Hoppe ◽

Shawn Li ◽

...

Keyword(s):

High Performance ◽

Inhibitory Concentration ◽

Medical Implants ◽

Implantable Medical Devices ◽

Antibiotic Solution ◽

Inhibition Zones ◽

Antibiotic Release ◽

Local Antibiotic ◽

Antibiotic Delivery

BACKGROUND: Implantable medical devices and hardware are prolific in medicine, but hardware associated infections remain a major issue. OBJECTIVE: To develop and evaluate a novel, biologic antimicrobial coating for medical implants. METHODS: Electrochemically compacted collagen sheets with and without crosslinked heparin were synthesized per protocol developed by our group. Sheets were incubated in antibiotic solution (gentamicin or moxifloxacin) overnight, and in vitro activity was assessed with five-day diffusion assays against Pseudomonas aeruginosa. Antibiotic release overtime from gentamicin infused sheets was determined using in vitro elution and high performance liquid chromatography (HPLC). RESULTS: Collagen-heparin-antibiotic sheets demonstrated larger growth inhibition zones against P. aeruginosa compared to collagen-antibiotic alone sheets. This activity persisted for five days and was not impacted by rinsing sheets prior to evaluation. Rinsed collagen-antibiotic sheets did not show any inhibition zones. Elution of gentamicin from collagen-heparin-gentamicin sheets was slow and remained above the minimal inhibitory concentration for gentamicin sensitive organisms for 29 days. Conversely, collagen-gentamicin sheets eluted their antibiotic payload within 24 hours. Overall, heparin associated sheets demonstrated larger inhibition zones against P. aeruginosa and prolonged elution profile via HPLC. CONCLUSION: We developed a novel, local antibiotic delivery system that could be used to coat medical implants/hardware in the future and reduce post-operative infections.

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