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•Bioactive material includes Hydroxyapatite (HA), Chitosan (CS) and Fullerene C60.•Cell viability test proves no toxicity of 0.3 and 0.15 mg/ml C60-containing composites.•C60 ...concentration of 0.004 mg/ml provides an antimicrobial effect against S. aureus.•C60 ensures a prolonged release of Anaesthesinum up to 18 days.•Anaesthesinum release is close to the zero-order kinetic release profile.
Bioactive composite material in the form of beads, based on natural polysaccharide Chitosan (CS), hydroxyapatite (HA), and C60 fullerene (C60), was synthesized under influence of microwave irradiation (MW). The bead is a 3D matrix consisting of CS macromolecules cross-linked with sodium tripolyphosphate with HA and C60 particles immobilized in its structure. XRD and FTIR data confirmed the formation of calcium deficient carbonate substituted HA with needle-shaped nanocrystallites of about 80 nm. MW does not influence CS structure. C60 enhances the beads shape stability. HPLC studies suggest the (up to 18 days) prolonged release of hydrophobic Anaesthesinum from C60-containing composites. Changing the C60 content allows adjusting the drug release time. The presence of CS and C60 provides the Anaestesinum release profile, according to the calculated correlation coefficient (r = 0.99), close to the zero order kinetic release profile. The inhibition zone test (ZOI) shows the antimicrobial activity of the composites containing 0.004 mg/ml C60 against S. aureus ATCC 25923 and E. coli ATCC 25922 (ZOI 16 ± 1 and 10 ± 2 mm, respectively). Cell viability test indicates no toxicity of 0.3 and 0.15 mg/ml C60-containing composites.
•Ca-deficient HA and carbonate CHA apatites were obtained under US or MW radiation.•The influence of US or MW radiation significantly shortens HA formation.•The cooling of reaction system has led to ...the formation of pure HA.•US and MW influences increase the bioactivity of apatites.•Thermal stability of apatites, synthesized under US and MW radiations, decreases.
The samples of hydroxyapatite and carbonate substituted hydroxyapatite (CHA) were obtained under the influence of physical factors, namely ultrasound (US) and microwave (MW) radiations. The results of Fourier transform infrared spectroscopy and X-ray diffraction analysis have proved the formation of the calcium deficient hydroxyapatite and B-type CHA with the Ca/P ratio in the ranges 1.62–1.87. In vitro studies have showed the increased bioactivity of the samples, synthesized under the influence of physical factors as compared to the standard ones. The samples of both groups, synthesized under the influence of 600 W MW, have shown the greatest stability in biological environment. In vivo tests confirm that obtained under US and MW radiations hydroxyapatite-based biomaterials are biocompatible, non-toxic and exhibit osteoconductive properties. The usage of US and MW radiations can significantly shorten the time (up to 5–20 min) of obtaining of calcium deficient hydroxyapatite and B-type CHA in nanopowder form, close in structure and composition to the biological hydroxyapatite.
The paper presents the results of studies of biocompatibility and antibacterial properties of multiphase nanocomposite materials based on HA-Alg-ZnO (hydroxyapatite‑sodium alginate-biphasic zinc ...oxide) and HA-ZnO (hydroxyapatite‑zinc oxide), which were synthesized from the analytically pure calcium nitrate tetrahydrate, ammonium hydrophosphate, hydrous ammonia, zinc nitrate hexahydrate and calcium chloride. The samples' antimicrobial activity assessment was carried out on Gram-negative (E. coli, P. aeruginosa) and Gram-positive bacteria (S. aureus and S. epidermidis) test cultures by the co-incubation and modified “agar diffusion” methods. The murine fibroblast cells were used for the biocompatibility tests and cytotoxicity evaluation. It was shown that synthesized nanocomposite material has a multiphase nanoscale architecture, where ZnO nanocrystals are represented by two lattices: cubic and hexagonal. The possible explanation of ZnO nanocrystals' phase transition is given. At the same time, a partial replacement of Ca2+ ions by Zn2+ ions in the HA lattice possibly occurs due to processing of composite by US radiation. The replacement was evidenced by the non-stoichiometric Ca/P ratio < 2.16, OPO lines' shifting on FTIR spectrum and TEM analysis. The studied composite demonstrate a pronounced antibacterial activity due to the incorporation of ZnO particles into sodium alginate and moistened powder of hydroxyapatite. Both forms of HA-ZnO (suspension) and HA-Alg-ZnO (beads) are biocompatible. An interpretation of the process of Zn ions' embedding into hydroxyapatite and alginate matrix is given, as well as their influence on the biomimetic composite properties is discussed in details.
A number of studies have shown that Zn effectively inhibits the growth and development of bacteria and yeast fungi. Zinc plays an important role in the creation of new antimicrobial agents, and zinc-doped hydroxyapatite will find further application in biomedicine.
In this regard, the phase states of zinc oxide, as well as the processes of calcium replacement by zinc in calcium apatite and in alginate should be explored fully. Nowadays we have lack of information and the study's results about those interactions.
The present study provides data of the multiphase morphology, antimicrobial activity, biocompatibility and cytotoxicity of the biomimetic nanostructured composite materials, such as sodium alginate/hydroxyapatite/ZnO based granules and hydroxyapatite/ZnO based hydrogel, and the establishing Zn ions' behavior patterns with another composite components.
•The synthesis technique provides occurring two type of ZnO nanocrystal lattice.•The interaction of biocomposite components was studied.•Hexagonal ZnO nanocrystals partially replace calcium ions.•Antibacterial activity assessed by different methods for several types of bacteria.•The synthesized biocomposites show high biocompatibility.
Bioactive composite material in the form of beads, based on natural polysaccharide Chitosan (CS), hydroxyapatite (HA), and C
fullerene (C
), was synthesized under influence of microwave irradiation ...(MW). The bead is a 3D matrix consisting of CS macromolecules cross-linked with sodium tripolyphosphate with HA and C
particles immobilized in its structure. XRD and FTIR data confirmed the formation of calcium deficient carbonate substituted HA with needle-shaped nanocrystallites of about 80 nm. MW does not influence CS structure. C
enhances the beads shape stability. HPLC studies suggest the (up to 18 days) prolonged release of hydrophobic Anaesthesinum from C
-containing composites. Changing the C
content allows adjusting the drug release time. The presence of CS and C
provides the Anaestesinum release profile, according to the calculated correlation coefficient (r = 0.99), close to the zero order kinetic release profile. The inhibition zone test (ZOI) shows the antimicrobial activity of the composites containing 0.004 mg/ml C
against S. aureus ATCC 25923 and E. coli ATCC 25922 (ZOI 16 ± 1 and 10 ± 2 mm, respectively). Cell viability test indicates no toxicity of 0.3 and 0.15 mg/ml C
-containing composites.
Single-walled carbon nanotubes (SWCNTs) containing biomaterial with enhanced mechanical properties for the potential orthopedic application were synthesized and investigated. X-ray diffraction and ...X-ray fluorescence analysis were indications of the formation of calcium-deficient (Ca/P = 1.65) hydroxyapatite (HA) with a small carbonate content under influence of microwave irradiation. The investigated mechanical properties (maximal relative deformation, compressive strength and Young’s modulus) of SWCNT loaded HA–alginate composites confirm their dependence on SWCNTs content. The compressive strength of HA–alginate–SWCNT and the HA–alginate control (202 and 159 MPa, respectively) lies within the values characteristic for the cortical bone. The addition of 0.5% SWCNT, in relation to the content of HA, increases the Young's modulus of the HA–alginate–SWCNT (645 MPa) compared to the SWCNT-free HA–alginate sample (563 MPa), and enhances the material shape stability in simulated physiological conditions. Structural modeling of HA–alginate–SWCNT system showed, that physical adsorption of SWCNT into HA–alginate occurs by forming triple complexes stabilized by solvophobic/van der Waals interactions and H-bonds. The high-performance liquid chromatography demonstrated the influence of SWCNTs on the sustained anaesthesinum drug (used as a model drug) release (456 h against 408 h for SWCNT-free sample). Cell culture assay confirmed biocompatibility and stimulation of osteoblast proliferation of 0.05% and 0.5% SWCNT-containing composites during a 3-day cultivation. All these facts may suggest the potential possibility of using the SWCNT-containing materials, based on HA and alginate, for bone tissue engineering.
The novel bioactive composite material based on hydroxyapatite and multi-walled carbon nanotubes filled by iron was synthesized by the “wet chemistry” method and characterized in detail by various ...experimental techniques including the X-ray diffraction, Fourier transform infrared and energy-dispersive X-ray fluorescence spectroscopy, thermogravimetric and differential thermal analysis. The swelling behaviour was quantified by measuring the changes in sample weight as a function of sample immersion time in a phosphate buffered saline (PBS). Bioactivity test was carried out by soaking the samples in PBS. The material composition influence on the model drug release was studied using the high-performance liquid chromatography method. Finally, the mechanical properties (maximal relative deformation, strength and Young's modulus) of the samples under loading were investigated too. The findings clear demonstrate the possibility of application of the created composite material in bioengineering of bone tissue to fill bone defects of various geometries with the function of prolonged release of the drug. It is assumed that this composite material can be used in 3D modeling of areas of bone tissue that have to bear a mechanical load.
•The novel bioactive composite material based on hydroxyapatite and multi-walled carbon nanotubes filled by iron was synthesized by the "wet chemistry" method and characterized in detail by various experimental techniques.•Bioactivity test was carried out by soaking the samples in a phosphate buffered saline.•The material composition influence on the model drug release was studied using the high-performance liquid chromatography method.•The mechanical properties of the samples under loading were investigated.•The findings demonstrate the possibility for a application of the created composite material in bioengineering of bone tissue to fill bone defects of various geometries with the function of prolonged release of the drug.
The aim of this short review was to discuss applications of a unique biopolymer chitosan in practical medicine, especially for bone tissue engineering. The article highlights the preparation and ...properties of innovative chitosan-based biomaterials such as CaP-chitosan (CS-CP)-composites and chitosan-alginate (CS-AG)-scaffolds. This paper takes a closer look at the physicochemical properties, spectral characteristics and chemical modifications of the chitosan molecule. The obtained chitosan-apatite composites were analysed using X-ray diffraction to verify the crystalline nature of their structures. It was observed that the addition of chitosan to the composite material reduces apatite crystallinity. Besides, an accent was made on antibacterial properties of chitosan, the use of chitosan nanoparticles to produce nanofibers and controlled drug delivery systems. Keywords: chitosan, hydroxyapatite, biocomposites, X-ray diffraction
The undamaged structure and functionality of the skeleton are a prerequisite for ensuring the quality of human life. The introduction of the latest treatment methods and prosthetics in traumatic ...surgery, oncology, cranial surgery, and dentistry form a demand for biomaterials with functionalized properties. The growth of new bone tissue is a cell-regulated process based on creating a specific bone morphology, which combines the organic matrix and its inorganic content. The inorganic component of human bones and teeth is calcium deficiency hydroxyapatite (cdHA), with a molar ratio of Ca/P ranging from 1.5 to 1.67. The combination of cdHA and natural polymers in the material allows the incorporation of proteins and growth factors into the polymer matrix. It promotes biocompatibility and the growth of new bone tissue. This review considers the critical role of the porosity parameter of biomaterials (BM) in their use for bone regeneration. Porosity is an essential characteristic of BM and guarantees the interaction of the material with cells in bone formation, promoting vascularization and the process of biosorption of synthetic graft when it is replaced by newly formed native bone. At the same time, the degree of porosity should correlate with mechanical stability to maintain the structural integrity of BM in the process of hard tissue regeneration. Processes involving cells and proteins during BM implantation with both high (70–80 %) and low (≤ 45 %) degrees of porosity are considered. Data on existing methods of obtaining BM in porous scaffolds are given. The specified degree of porosity is provided by chemical (cross-linking) and physical (sublimation) methods. The effects of pores of different sizes and shapes on bone formation and vascularization are considered. It is shown that porosity is an influential factor influencing the mechanical properties of scaffolds, in particular, the stiffness of BM - a parameter that affects the proliferation of osteoblasts by regulating cell adhesion in the scaffold structure. The influence of the biopolymer component (Sodium Alginate - AN) on the porosity and swelling of hybrid apatite-biopolymer (HA/AN) composites, in which nanometric needle crystallites represent HA, is analyzed in detail.
Influence of the mineralization process of collagen (Cg) by hydroxyapatite (HA) on interactions with water molecules was investigated using infrared and Raman spectroscopy and piezogravimetry ...methods. Hydroxyapatite was synthesized using a simplified basic reaction with and without Ti ions, followed by phase analysis with X-ray diffraction spectroscopy (XRD). Cg–HA film samples have been prepared by a process of slow evaporation of water from the solution at 4 °C. It was found that in the presence of HA some Cg hydration sites, probably corresponding to its gap region, are closed, at least partly, for direct interactions with water molecules from the Cg hydration shell. A model illustrating early mineralization process of two Cg layers in the presence of water molecules are proposed for explaining of obtained experimental data.
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