scholarly journals Bioactive composite gradient coatings of nano-hydroxyapatite/polyamide66 fabricated on polyamide66 substrates

2012 ◽  
Vol 9 (72) ◽  
pp. 1450-1457 ◽  
Author(s):  
Di Huang ◽  
Yi Zuo ◽  
Jidong Li ◽  
Qin Zou ◽  
Li Zhang ◽  
...  
Keyword(s):  
Cell Attachment ◽  
Polymeric Matrix ◽  
Bone Tissue Regeneration ◽  
Gradual Transition ◽  
Chemical Corrosion ◽  
Bioactive Coating ◽  
High Adhesion ◽  
Coating Method ◽  
Coating Methods ◽  
Convenient Technique

Tightly bonding of bioactive coating is the first crucial need for orthopaedic implants. This study describes a novel and convenient technique to prepare bioactive coating with high adhesion on orthopaedic substitutes made of polymeric matrix. Here, a chemical corrosion method has been adopted to fabricate a coating on the surface of injection-moulded polyamide66 (PA66) substrates by corrosive nano-hydroxyapatite/polyamide66 (n-HA/PA66) composite slurry. Scanning electron microscopy observation shows that a porous chemical corrosion region presents between the coating and dense PA66 substrate. Energy-dispersive X-ray spectroscopy analysis indicates that the chemical corrosion region is mainly composed of PA66 matrix, and the coating layer is an n-HA-rich layer. Both the pore size and n-HA composition increase gradually from the polymeric substrate towards the coating surface. Mechanical testing shows the bonding strength can reach 13.7 ± 0.2 MPa, which is much higher than that fabricated on polymeric matrix by other coating methods. The gradual transition in coating structure and composition benefits for the interface bonding and for the surface bone-bonding bioactivity. Subsequent cell experiments corroborate n-HA-rich coating and a porous structure is benefitting for cell attachment and proliferation. The convenient coating method could be popularized and applied on similar polymer implants to produce a tightly and porous bioactive coating for bone tissue regeneration.

scholarly journals Osteogenic Properties of 3D-Printed Silica-Carbon-Calcite Composite Scaffolds: Novel Approach for Personalized Bone Tissue Regeneration

2021 ◽  
Vol 22 (2) ◽  
pp. 475
Author(s):  
Parastoo Memarian ◽  
Francesco Sartor ◽  
Enrico Bernardo ◽  
Hamada Elsayed ◽  
Batur Ercan ◽  
...  
Keyword(s):  
Osteogenic Differentiation ◽  
Bone Tissue ◽  
Cell Attachment ◽  
Three Dimensional ◽  
Bone Tissue Regeneration ◽  
Hemolysis Assay ◽  
Novel Approach ◽  
Related Transcription Factor ◽  
Diphenyl Tetrazolium Bromide

Carbon enriched bioceramic (C-Bio) scaffolds have recently shown exceptional results in terms of their biological and mechanical properties. The present study aims at assessing the ability of the C-Bio scaffolds to affect the commitment of canine adipose-derived mesenchymal stem cells (cAD-MSCs) and investigating the influence of carbon on cell proliferation and osteogenic differentiation of cAD-MSCs in vitro. The commitment of cAD-MSCs to an osteoblastic phenotype has been evaluated by expression of several osteogenic markers using real-time PCR. Biocompatibility analyses through 3-(4,5-dimethyl- thiazol-2-yl)-2,5-diphenyl tetrazolium bromide (MTT), lactate dehydrogenase (LDH) activity, hemolysis assay, and Ames test demonstrated excellent biocompatibility of both materials. A significant increase in the extracellular alkaline phosphatase (ALP) activity and expression of runt-related transcription factor (RUNX), ALP, osterix (OSX), and receptor activator of nuclear factor kappa-Β ligand (RANKL) genes was observed in C-Bio scaffolds compared to those without carbon (Bio). Scanning electron microscopy (SEM) demonstrated excellent cell attachment on both material surfaces; however, the cellular layer on C-Bio fibers exhibited an apparent secretome activity. Based on our findings, graphene can improve cell adhesion, growth, and osteogenic differentiation of cAD-MSCs in vitro. This study proposed carbon as an additive for a novel three-dimensional (3D)-printable biocompatible scaffold which could become the key structural material for bone tissue reconstruction.

PCL and PCL/PLA Scaffolds for Bone Tissue Regeneration

2013 ◽  
Vol 683 ◽  
pp. 168-171 ◽  
Author(s):  
Tatiana Patrício ◽  
Antonio Gloria ◽  
Paulo J. Bártolo
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Tissue Regeneration ◽  
Cell Attachment ◽  
Bone Tissue Regeneration ◽  
Engineering Applications ◽  
Printing System

This paper investigates the use of PCL and PCL/PLA scaffolds, produced using a novel additive biomanufacturing system called BioCell Printing, for bone tissue engineering applications. Results show that the BioCell Printing system produces scaffolds with regular and reproducible architecture, presenting no toxicity and enhancing cell attachment and proliferation. It was also possible to observe that the addition of PLA to PCL scaffolds strongly improves the biomechanical performance of the constructs.

Transformed Cuttlefish Bone Scaffolds for Bone Tissue Engineering

2010 ◽  
Vol 89-91 ◽  
pp. 47-52 ◽  
Author(s):  
Elisa Battistella ◽  
Silvia Mele ◽  
S. Pietronave ◽  
Ismaela Foltran ◽  
G.I. Lesci ◽  
...  
Keyword(s):  
Tissue Engineering ◽  
Bone Tissue Engineering ◽  
Bone Tissue ◽  
Cell Attachment ◽  
Engineering Application ◽  
Surface Characteristics ◽  
Bone Tissue Regeneration ◽  
Tissue Engineering Application ◽  
Bone Scaffolds ◽  
Surface Development

Nature is full of many interesting things to work with, but many natural resources are also protected. In this view the recycling of aquaculture and fishery residues may lead to the manufacture of new devices and the isolation of new molecules with potential application in medicine. The aim of the present study was to explore the possibility to transform the cuttlefish bone into an hydroxyapatite scaffold suitable for bone tissue engineering application. The mixture of different lamellar porous structure of cuttlefish bone from the species Sepia Officinalis was selected and characterized, according to morphology (including porosity, surface development, surface characteristics) and mechanical properties. The material was transformed into suitable scaffold for bone tissue regeneration, trying to totally or partially convert calcium carbonate (aragonite) into calcium phosphate (hydroxyapatite HA) using hydrothermal transformation. The studies on cell attachment and proliferation (by MTT assay at different experimental times), cell morphology with Scanning Electron Microscopy (SEM), alkaline phosphatase (ALP) and osteocalcin (OC) activities and expressions by mouse osteoblast-like MC3T3-E1 cells on HA were investigated at different experimental times in cultures, in comparison with those observed on titanium specimens used as a control (ET and ST). Cell proliferation was less in HA transformed cuttlefish bone scaffolds than in ET and ST specimens. In contrast, good performance for osteoblasts differentiation was observed on HA transformed cuttlefish bone scaffolds, similar to those observed onto titanium scaffolds.

scholarly journals A durable and biocompatible ascorbic acid-based covalent coating method of polydimethylsiloxane for dynamic cell culture

2017 ◽  
Vol 14 (132) ◽  
pp. 20170318 ◽  
Author(s):  
Joni Leivo ◽  
Sanni Virjula ◽  
Sari Vanhatupa ◽  
Kimmo Kartasalo ◽  
Joose Kreutzer ◽  
...  
Keyword(s):  
Ascorbic Acid ◽  
Cell Attachment ◽  
Collagen Type I ◽  
Contact Angle Measurement ◽  
Angle Measurement ◽  
Type I ◽  
Simple Method ◽  
Dynamic Conditions ◽  
Coating Method ◽  
Cross Linker

Polydimethylsiloxane (PDMS) is widely used in dynamic biological microfluidic applications. As a highly hydrophobic material, native PDMS does not support cell attachment and culture, especially in dynamic conditions. Previous covalent coating methods use glutaraldehyde (GA) which, however, is cytotoxic. This paper introduces a novel and simple method for binding collagen type I covalently on PDMS using ascorbic acid (AA) as a cross-linker instead of GA. We compare the novel method against physisorption and GA cross-linker-based methods. The coatings are characterized by immunostaining, contact angle measurement, atomic force microscopy and infrared spectroscopy, and evaluated in static and stretched human adipose stem cell (hASC) cultures up to 13 days. We found that AA can replace GA as a cross-linker in the covalent coating method and that the coating is durable after sonication and after 6 days of stretching. Furthermore, we show that hASCs attach and proliferate better on AA cross-linked samples compared with physisorbed or GA-based methods. Thus, in this paper, we provide a new PDMS coating method for studying cells, such as hASCs, in static and dynamic conditions. The proposed method is an important step in the development of PDMS-based devices in cell and tissue engineering applications.

scholarly journals Research and development of processes of vacuum ion-plasma parts surface treatment

2021 ◽  
Vol 2131 (2) ◽  
pp. 022037
Author(s):  
A Sychev ◽  
I Kolesnikov ◽  
A Voropaev ◽  
I Bolshykh
Keyword(s):  
Surface Treatment ◽  
Lower Layer ◽  
High Hardness ◽  
Middle Layer ◽  
Substrate Material ◽  
Wear Resistant Coatings ◽  
Ion Plasma ◽  
High Adhesion ◽  
Coating Methods ◽  
Combined Coatings

Abstract The application of electron-ion-plasma technologies for increasing the service life of machine parts, tools and technological equipment has been investigated. The technology of vacuum ion-plasma surface treatment is proposed for the deposition of coatings, which makes it possible to create internal, external and combined coatings. The manufacturability of coating methods is largely determined by the level of the developed equipment. The entire technological process of deposition of wear-resistant coatings on parts of friction units is carried out in one cycle on a BRV600F vacuum unit, which is equipped with all the necessary technical means. A method has been developed for the technology of obtaining a superhard carbon-metal coating with desired properties, namely, improving the quality of diamond-like films by changing their structure and composition, while the lower layer should have high adhesion to the substrate material, the middle layer should have high hardness and increased wear resistance, and the upper layer should have good thermal conductivity and heat resistance with low coefficient of friction.

scholarly journals Assessment of hot-melt coating methods for multiparticulate substrates: Mortar-coating vs. pan-coating

2021 ◽  
Vol 71 (1) ◽  
pp. 35-54
Author(s):  
Jelisaveta Ignjatović ◽  
Jelena Đuriš ◽  
Mihal Đuriš ◽  
Teodora Bočarski ◽  
Vanja Vasilijević ◽  
...  
Keyword(s):  
Sodium Chloride ◽  
Liquid Paraffin ◽  
Practical Method ◽  
Coating Agent ◽  
Coated Particles ◽  
Coated Material ◽  
Model Substance ◽  
Coating Method ◽  
Coating Methods ◽  
Hot Melt

Hot-melt coating (HMC) is an alternative, solvent-free coating method generally used to modify substrate release rate and/or mask its unpleasant taste. The aim of this study was to assess two HMC methods (pan-coating and mortar-coating) by assaying functional properties of the coated material. The selected substrates included highly soluble sodium chloride (model substance) and caffeine (bitter drug), and the coating agent was glycerol distearate without/with the addition of liquid paraffin. Experiments with sodium chloride revealed that pan-coating yielded particles of more regular shape, while mortar-coating yielded samples of more uniform coating layer. The flowability of the coated material depended on the particle size. Sustained sodium chloride release was achieved for all mortar-coated and some pan-coated samples. The analysis of the results indicated mortar-coating as a preferable HMC method for caffeine coating. The resulting caffeine yield in the coated samples was high (99%), the material showed satisfactory mechanical properties and drug release from the coated particles was sustained. Overall, the obtained results suggest that both pan-and mortar-coating can be used to sustain the release of drugs with unpleasant taste, but mortar-coating can be considered as a more simple and practical method that can be potentially used in compounding pharmacies.

scholarly journals PROMISING COMPOSITE MATERIALS BASED ON NANOSCALE APATITE WITH GELATIN AS A BINDING AGENT

2021 ◽  
pp. 664-671
Author(s):  
Екатерина Анатольевна Богданова ◽  
Владимир Михайлович Скачков
Keyword(s):  
Colloidal Suspension ◽  
Aqueous Suspension ◽  
Gelatin Solution ◽  
Binding Agent ◽  
Porous Films ◽  
Bioactive Coatings ◽  
Bioactive Material ◽  
Bioactive Coating ◽  
High Adhesion ◽  
Patent Applications

Порошки наноразмерных гидроксиапатита и фторапатита синтезированы методом осаждения из растворов. В качестве связующего вещества использован пищевой желатин. Такая композиция имеет высокую адгезию на материалах различной природы и пористости. Получены также пористые пленки и гранулы с развитой удельной поверхностью. Рассмотрены их микроструктуры. Изучена возможность использования коллоидной суспензии и водной суспензии кристаллического апатита в сочетании с раствором желатина в качестве биоактивного материала, как для создания покрытий, так и получения гранул. Установлено, что использование порошка апатита совместно с желатином позволяет существенно сократить сроки формирования биоактивного покрытия и значительно повысить его адгезионную прочность. Сопоставлены получаемые гранулы апатита по размерам в зависимости от концентрации желатина в водном растворе. На разработанные биоактивные покрытия и гранулированный материал на основе наноразмерного апатита со связующим агентом поданы заявки на патент. Nanoscale hydroxyapatite and fluorapatite powders were synthesized by precipitation from solutions. Food gelatin is used as a binder. This composition has a high adhesion on materials of different nature and porosity. Porous films and granules with a developed specific surface area were also obtained. Their microstructures are considered. The possibility of using a colloidal suspension and an aqueous suspension of crystalline apatite in combination with a gelatin solution as a bioactive material, both for creating coatings and obtaining granules, has been studied. It is established that the use of apatite powder together with gelatin can significantly reduce the time of formation of a bioactive coating and significantly increase its adhesive strength. The obtained apatite granules are compared in size depending on the concentration of gelatin in an aqueous solution. Patent applications have been filed for the developed bioactive coatings and granular material based on nanoscale apatite with a binding agent.

scholarly journals Effect of Mo Addition on the Chemical Corrosion Process of SiMo Cast Iron

Materials ◽  
2020 ◽  
Vol 13 (7) ◽  
pp. 1745
Author(s):  
Marcin Stawarz ◽  
Paweł M. Nuckowski
Keyword(s):  
Cast Iron ◽  
Substrate Material ◽  
Metallographic Analysis ◽  
X Ray Diffraction ◽  
Oxide Layers ◽  
Chemical Corrosion ◽  
High Adhesion ◽  
Cyclic Operation ◽  
Mo Content ◽  
Si Content

The study was carried out to evaluate five SiMo cast iron grades and their resistance to chemical corrosion at elevated temperature. Corrosion tests were carried out under conditions of an actual cyclic operation of a retort coal-fired boiler. The duration of the study was 3840 h. The range of temperature changes during one cycle was in the range of 300–650 °C. Samples of SiMo cast iron with Si content at the level of 5% and variable Mo content in the range 0%–2.5% were used as the material for the study. The examined material was subjected to preliminary metallographic analysis using scanning microscopy and an Energy dispersive spectroscopy (EDS) system. The chemical composition was determined on the basis of a Leco spectrometer and a Leco carbon and sulfur analyzer. The examination of the oxide layer was carried out with the use of Scanning electron microscope (SEM), EDS, and X-ray diffraction (XRD) methods. It was discovered that, in the analyzed alloys, oxide layers consisting of Fe2O3, Fe3O4, SO2, and Fe2SiO4 were formed. The analyzed oxide layers were characterized by high adhesion to the substrate material, and their total thickness was about 20 μm.

Thin coatings for paper by foam coating

TAPPI Journal ◽  
2014 ◽  
Vol 13 (7) ◽  
pp. 9-19 ◽  
Author(s):  
KARITA KINNUNEN-RAUDASKOSKI ◽  
TUOMO HJELT ◽  
EIJA KENTTÄ ◽  
ULLA FORSSTRÖM
Keyword(s):  
Pilot Scale ◽  
Coating Materials ◽  
Coating Technology ◽  
Paper Properties ◽  
Thin Coatings ◽  
Paper Surface ◽  
Ultrathin Layers ◽  
Coating Method ◽  
Coating Methods ◽  
New Type

The future of paper products is predicted to lie in intelligent and functional paper properties. These properties are achieved by using coating materials, which are usually very expensive, but the amount needed is also very small. The application of these small amounts requires a new type of coating method; conventional coating methods used in the industry today are not capable of providing ultrathin layers. In this study we introduce foam coating, a technology widely used in the textile and nonwovens industries. Foam coating technology offers a unique opportunity to apply coating on the web surface thinly enough to be economically viable. Our pilot-scale studies show that a thin coating of nanomaterial at a thickness of 1 μm or less and coat weight of 0.3-2.0 g/m2 is enough to change paper surface properties and enable the functionalization of the paper surface. This report describes the applicability of the curtain-like foam coating technology in unmodified cellulose nanofiber (CNF) applications.

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