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1

In vitrotests of dense hydroxyapatite materials

100%

Sobczak A., Kida A., Kowalski Z., Wzorek Z.

Polish Journal of Chemical Technology

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2009

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vol. 11

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issue 1

44-49

EN

The paper presents the results of the calcining process of deproteinised and defatted bone pulp called bone sludge. The calcining process was performed in two stages. The first step of the calcining process was realized at the temperature of 600°C in a rotary kiln. In the second stage the obtained bone ashes were calcined at five different temperatures from 650°C to 950°C for 2 hours in a chamber kiln and in air atmosphere. The products of the calcining process were characterized by the XRD method. Calcium content was determined by titration whereas the contents of total phosphorus and acid-soluble phosphorus - by the spectrophotometric method. The X-ray analysis confirmed that hydroxyapatite is the main component of the calcining products. Calcium and phosphorus contents were kept at the level of 40% and 17.5%, respectively, which corresponded to the Ca/P ratio of not stechiometric hydroxyapatite. In vitro studies, in the simulated body fluid, Ringer liquid and distilled water were realised. The measurements of pH value of SBF and Ringer fluid were realized. Additionally electrical conductivity as well as pH for distilled water where conducted. The goal of these tests was to evaluate chemical durability of dense hydroxyapatite materials.

2

CHITIN NANOFIBRES AS REINFORCEMENT FOR HYDROXYAPATITE-BASED COMPOSITE PREPARATION

100%

Machałowski T., Kozłowski M., Kołodziejczak-Radzimska A., Jakubowicz J., Jesionowski T.

Progress on Chemistry and Application of Chitin and its Derivatives

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2022

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vol. 27

162-174

EN

The development and improvement of chitin applications have drawn special attention from the global scientific community due to their extraordinary features and abundance. In this study, β-chitin nanofibres were obtained using the ultrasonication treatment method. Then, hydroxyapatite/nanochitin (HAp/NCh) composites were prepared at different maturation times. In this case, mixtures of various amounts of β-chitin nanofibres (1%, 2%, and 5%) were added during the HAp precipitation approach. The prepared HAp/NCh materials were characterised with Fourier-transform infrared spectroscopy, thermogravimetric analysis, X-ray diffraction, and energy-dispersive X-ray spectroscopy. The surface of prepared specimens was observed using scanning electron microscopy. The presence of nanofibres was confirmed by non-invasive backscattering with dynamic light scattering particle size analysis. Moreover, the synergic effect of chitin nanofibres on the mechanical resistance of HAp-based composite was investigated. The sample with 5% of chitin nanofibres exhibited about 10 times higher compression strength than the pure HAp. All these results essentially indicate that the prepared material can be a potential candidate for bone tissue engineering applications and further development.

3

The suitability of scanning electron microscopy in the evaluation of bone structure surfaces and selection of alloplastic materials for facial skeletal reconstruction

100%

Job K., Składzień J.

Polish Journal of Otolaryngology

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2021

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vol. 75

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issue 4

14-19

EN

Introduction: Functional and aesthetic problems can arise even from small losses created in the facial skeleton. Injuries and oncological surgeries are the most frequent causes of these losses within the facial skeleton. Advances in surgical interventions have allowed for ever-increasing degrees of resections, increasing oncological radicality as well as treatment effectiveness, providing the patient with the chance for a longer life. However, this subsequently requires the use of even more advanced reconstruction techniques in order to restore quality of life and comfort to the patient, as well as enable their return to professional and social activities. The necessity of reconstructive surgery applies not only to patients with cancer, but also to patients with impaired or failing sensory and organ function as a result of inflammatory conditions, injuries, or non-oncological surgeries. There are many available reconstruction procedures, which depend on the location of the loss, the type of tissue lost, the degree of loss and patient-dependent factors. Materials used in reconstruction surgeries may include the patients’ tissues when available, and artificial reconstruction materials otherwise. Material and methods: The analysis involved fragments of bone tissue removed during surgery. Due to the nature of the medical procedure and the inability to replant the tissue, it was regarded as medical waste. The preparations used were observed under an optical microscope and an electron scanning microscope, and a chemical analysis was performed. The chemical composition of samples was analysed using a low vacuum detector (LVD) at an accelerating voltage of 15 kV and 10 kV and at a spot size of 4 and 3.5. The observations were performed in a secondary electron (SE) detection system. Results: Observation of parameters under an optical microscope and of images obtained using an electron scanning microscope showed the presence of typical, compact bone tissue with varied surface shapes in each case (various degrees of unevenness and porosity). Chemical composition analysis confirmed the presence of compounds from the CaO-P2O5-H20 system. The Ca/P (calcium/phosphorus) ratio obtained from the chemical analysis varied from 1.33 to 2.1, and indicated a varied morphology of calcium phosphates forming the bone structures of the facial skeleton. Conclusions: 1. Calcium phosphates are characterised by excellent biocompatibility because of their chemical affinity to bone, and are ideal for the reconstruction of bone losses within the facial skeleton. 2. Biodegradable polymers have the highest functional potential among several groups of biomaterials used in tissue engineering because of their ability to be tailored individually, in addition to their high biocompatibility.

4

Studies on sintering process of synthetic hydroxyapatite

100%

Malina D., Biernat K., Sobczak-Kupiec A.

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2013

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vol. 60

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issue 4

851-855

EN

In this study the effect of sintering process in different temperatures on microstructure and morphological properties of sintered hydroxyapatite (HAp) was investigated. HAp powder was prepared by wet precipitation method from following reagents: Ca(OH)2 + H3PO4 in an alkaline conditions. Thermal analysis (TA), X-Ray diffraction method (XRD), FT-IR spectrometry (FT-IR) and scanning electron microscopy (SEM) were used to elaborate the phase composition and properties of sintered HAp samples and raw HAp powder as well. The total and apparent density and total porosity of sintered compacts, shrinkage and weight loss during the sintering were also measured. The results show that there is a difference in sintering behavior of synthetic hydroxyapatites depending on sintering temperature. The main differences refer to the loss of mass, shrinkage, changes in porosity and density of the investigated materials.

5

Surface engineering in formation of modern multilayer structures - biofunctional hydroxyapatite coatings produced by pulsed laser ablation and glow discharge nitriding multiplex method

100%

Major B., Wierzchoń T., Mróz W., Haberko K., Ebner R., Bonarski J., Major R., Prokopiuk A.

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issue 4

6

Manufacturing of phosphoric acid from hydroxyapatite, contained in the ashes of the incinerated meat-bone wastes

100%

Krupa-Żuczek K., Kowalski Z., Wzorek Z.

Polish Journal of Chemical Technology

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2008

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vol. 10

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issue 3

13-20

EN

The results of the investigations concerning phosphoric acid manufacturing, by the extraction method, from the ashes containing hydroxyapatite, obtained through the thermal treatment of bone sludge have been presented. The incinerated bone sludge with ~ 16% P content and the minimal amount of impurities can be an alternative source for phosphoric acid production. The process consists in two stages. In the 1st stage, reaction of hydroxyapatite with phosphoric acid resulting in monocalcium phosphate formation in the solution obtained is carried out. The tests revealed that overall hydroxyapatite dissolution in phosphoric acid takes place when the concentration is 37% H3PO4. In the 2nd stage monocalcium phosphate is converted into calcium sulphate using concentrated sulphuric acid at the recommended temperature of 95°C. The principles of the technological idea of the process of phosphoric acid manufacturing from HA-containing ashes, obtained by bone wastes incineration, as well as a preliminary economic analysis for the production of 10 000 t/year of food-grade phosphoric acid have been developed.

7

Investigation of Bio-Functional Properties of Titanium Substrates after Hybrid Oxidation

88%

Jasinski J. J., Jasinski J. J.

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vol. 65

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issue 1

8

The roles of annexins and alkaline phosphatase in mineralization process.

88%

Balcerzak M., Hamade E., Zhang L., Pikula S., Azzar G., Radisson J., Bandorowicz-Pikula J., Buchet R.

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2003

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vol. 50

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issue 4

1019-1038

EN

In this review the roles of specific proteins during the first step of mineralization and nucleation are discussed. Mineralization is initiated inside the extracellular organelles-matrix vesicles (MVs). MVs, containing relatively high concentrations of Ca2+ and inorganic phosphate (Pgi), create an optimal environment to induce the formation of hydroxyapatite (HA). Special attention is given to two families of proteins present in MVs, annexins (AnxAs) and tissue-nonspecific alkaline phosphatases (TNAPs). Both families participate in the formation of HA crystals. AnxAs are Ca2+- and lipid-binding proteins, which are involved in Ca2+ homeostasis in bone cells and in extracellular MVs. AnxAs form calcium ion channels within the membrane of MVs. Although the mechanisms of ion channel formation by AnxAs are not well understood, evidence is provided that acidic pH or GTP contribute to this process. Furthermore, low molecular mass ligands, as vitamin A derivatives, can modulate the activity of MVs by interacting with AnxAs and affecting their expression. AnxAs and other anionic proteins are also involved in the crystal nucleation. The second family of proteins, TNAPs, is associated with Pi homeostasis, and can hydrolyse a variety of phosphate compounds. ATP is released in the extracellular matrix, where it can be hydrolyzed by TNAPs, ATP hydrolases and nucleoside triphosphate (NTP) pyrophosphohydrolases. However, TNAP is probably not responsible for ATP-dependent Ca2+/phosphate complex formation. It can hydrolyse pyrophosphate (PPi), a known inhibitor of HA formation and a byproduct of NTP pyrophosphohydrolases. In this respect, antagonistic activities of TNAPs and NTP pyrophosphohydrolases can regulate the mineralization process.

9

Synthesis of bio-active titanium oxide coatings stimulated by electron-beam plasma

88%

Vasilieva T., Sokolov I., Sigarev A., Tun Win A.

Open Chemistry

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2015

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vol. 13

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issue 1

EN

Advantages of the electron-beam plasma (EBP) for production of bioactive titanium oxide coatings were experimentally studied. The coatings were synthesized in EBP of oxygen on the surface of plane titanium substrates. A number of analytical techniques were used to characterize morphology, chemical composition, and structure of the synthesized titanium oxide. The analysis showed the titanium oxide (IV) in the rutile form to predominate in the coatings composition. The samples with plasmachemically synthesized TiO2-coatings were more hydrophilic than untreated titanium. The effect was stable during two weeks and then the degradation of the wettability began. The EBP-stimulated TiO2 synthesis improved the hydroxyapatite formation on the surface of plane titanium substrates. The EBP-stimulated TiO2 synthesis is promising technique to produce bioactive coatings on the surface of titanium medical dental and bone implants. The computer simulation of plasma-surface interaction was carried out to predict the plasma composition, to find the spatial distribution of the sample temperature, and to calculate the flows of the chemically active plasma particles bombarding the tube wall. The flows of atomic and singlet oxygen were found to be the most intensive and, therefore, these particles are likely to be responsible for the formation of the biocompatible TiO2-coaings.

10

Structural and morphological properties of HA-ZnO powders prepared for biomaterials

88%

Moldovan M., Prodan D., Popescu V., Prejmerean C., Saroși C., Saplonţai M., Țălu S., Vasile E.

Open Chemistry

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2015

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vol. 13

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issue 1

EN

The purpose of this study was to investigate the structural and morphological properties of hydroxyapatite – zinc oxide (HA-ZnO) powders prepared to be used in an endodontic sealer formulation. The HA-ZnO was synthesized from hydroxyapatite (HA) in the presence of zinc oxide (ZnO) sol. The starting reagents were CaO, H3PO4 and a suspention of ZnO (25% in water). Following precipitation, the obtained sol was subjected to heat treatment at 110°C, 400°C, 850°C and 1050°C. The study focused on the influence of the thermal treatment on the cristallinity of precipitated powders. X-ray diffraction was used in order to study the structural properties of the obtained powder. Fourier Transform Infrared Spectroscopy (FT-IR) was used in order to evaluate the interactions between HA and ZnO. The morphology of the samples was studied by Scanning Electron Microscopy (SEM). Transmission Electron Microscopy and High Resolution Transmission Electron Microscopy (TEM, HRTEM) were used for the determination of particle size and fractal analysis. The fractal analysis of images using the standard box-counting method is presented and the results are discussed. It was demonstrated that the fractal dimension analysis is a useful method to quantitatively describe the complex microstructures and it can reveal the relation between fractal parameters.

11

Evaluation of the biomedical properties of hydroxyapatite obtained from bone waste

75%

Sobczak A., Kida A., Kowalski Z., Wzorek Z.

Polish Journal of Chemical Technology

|

2009

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vol. 11

|

issue 1

37-43

EN

The method of obtaining hydroxyapatite by thermal treatment of deproteinised and defatted bone pulp called bone sludge was presented. The products of the calcining process were characterized with X-ray diffraction (XRD) and Fourier transformed infrared spectroscopy (FT-IR). The calcium content was determined with titration, whereas the contents of total phosphorus - with a spectrophotomertric method. X-ray investigations confirmed that hydroxyapatite was the main component of the calcining products in the calcining process. The FT-IR spectra confirmed that all organic substances were removed during the calcining process. On the basis of the research into physiological liquids the propensity to resorption of hydroxyapatite bioceramic was evaluated.

12

SURFACE PROPERTIES OF CHITOSAN COMPOSITES WITH POLY(VINYL ALCOHOL) AND HYDROXYAPATITE

75%

Lewandowska K.

Progress on Chemistry and Application of Chitin and its Derivatives

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2015

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vol. 20

177-182

EN

Surface properties of composites containing chitosan (Ch), poly(vinyl alcohol) (PVA) with hydroxyapatite (HAP) were investigated by contact angle measurements and atomic force microscopy (AFM). Thin films of Ch/HAP and Ch/PVA/HAP composites have been formed by casting methods from acetic acid solutions. Measurements of the contact angle for diiodomethane (D), and glycerol (G) on the surface of chitosan films, Ch/HAP and chitosan/PVA/HAP films were made and surface free energy was calculated. It was found that chitosan/HAP or Ch/PVA/HAP blend surface is enriched in high surface energy component i.e. chitosan. The study of composites by AFM showed a completely different morphology when compared with unmodified components. The roughness of composites increase after the addition of hydroxyapatite. This may indicates a strong interaction between the polymeric components and inorganic additive.

13

Synthesis of hydroxyapatite in a continuous reactor: a review

75%

Latocha J., Wojasiński M., Sobieszuk P., Ciach T.

Chemical and Process Engineering

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2018

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vol. 39

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issue 3

14

Examination of Sol-Gel Derived Hydroxyapatite Enhanced with Silver Nanoparticles using OCT and Raman Spectroscopy

75%

Głowacki M. J., Gnyba M., Strąkowska P., Gardas M., Kraszewski M., Trojanowski M., Strąkowski M. R.

Metrology and Measurement Systems

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2017

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vol. 24

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issue 1

15

Corrosion protection of 316L stainless steel by (PVDF/HA) composite coating using a spinning coating technique

75%

Hussein A. A., Dawood N. M., Emad A.-k. A., Hussein A. A., Dawood N. M., Emad A.-k. A.

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2021

16

SYNTHESIS OF NEW CHITOSAN-CARBONATE HYDROXYAPATITE COMPOSITES WITH POTENTIAL APPLICATION IN BONE TISSUE ENGINEERING – PHYSICOCHEMICAL ANALYSIS

75%

Urbaniak J., Kołodziejska B., Kaflak A.

Progress on Chemistry and Application of Chitin and its Derivatives

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2022

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vol. 27

217-227

EN

The subject of this study was the synthesis of 12 chitosan-hydroxyapatite (CH:HA) composites with different contents of carbonate ions (CO3 2-), in two weight ratios of CH to HA (30:70 and 50:50), and two viscosities of CH (low [L] and high [H]). The method of direct co-precipitation of the introduced reagents was used. The structure of the obtained materials was characterised by Fourier-transform infrared (FT-IR) spectroscopy, powder X-ray diffraction, and scanning electron microscopy. The FT-IR spectra revealed the bands and ranges of the characteristic bands for CH and HA. The presence of CO3 2- introduced into the structure of the obtained composites was identified by infrared spectroscopy. A reduction in the size of HA unit cells was observed in the obtained CH:HA biocomposites, in materials with a higher content of incorporated CO3 2-. The obtained nanomaterials are similar to natural bone tissue. Future research will focus on the evaluation of the obtained materials as a drug delivery system.

17

SYNTHESIS AND APPLICATION OF CHITOSAN HYDROXYAPATITE: A REVIEW

51%

Vokhidova N. R., Ergashev K. H., Rashidova S. S.

Progress on Chemistry and Application of Chitin and its Derivatives

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2022

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vol. 27

5-34

EN

In this review, the research devoted to synthesising chitosan apatites, their biologically active properties, and their application in medical practice is analysed. The data are from articles published between 2001 and 2022 on the formation of calcium- and phosphorus-containing chitosan composites and the mechanism of their interaction

Refine search results

In vitrotests of dense hydroxyapatite materials

CHITIN NANOFIBRES AS REINFORCEMENT FOR HYDROXYAPATITE-BASED COMPOSITE PREPARATION

The suitability of scanning electron microscopy in the evaluation of bone structure surfaces and selection of alloplastic materials for facial skeletal reconstruction

Studies on sintering process of synthetic hydroxyapatite

Surface engineering in formation of modern multilayer structures - biofunctional hydroxyapatite coatings produced by pulsed laser ablation and glow discharge nitriding multiplex method

Manufacturing of phosphoric acid from hydroxyapatite, contained in the ashes of the incinerated meat-bone wastes

Investigation of Bio-Functional Properties of Titanium Substrates after Hybrid Oxidation

The roles of annexins and alkaline phosphatase in mineralization process.

Synthesis of bio-active titanium oxide coatings stimulated by electron-beam plasma

Structural and morphological properties of HA-ZnO powders prepared for biomaterials

Evaluation of the biomedical properties of hydroxyapatite obtained from bone waste

SURFACE PROPERTIES OF CHITOSAN COMPOSITES WITH POLY(VINYL ALCOHOL) AND HYDROXYAPATITE

Synthesis of hydroxyapatite in a continuous reactor: a review

Examination of Sol-Gel Derived Hydroxyapatite Enhanced with Silver Nanoparticles using OCT and Raman Spectroscopy

Corrosion protection of 316L stainless steel by (PVDF/HA) composite coating using a spinning coating technique

SYNTHESIS OF NEW CHITOSAN-CARBONATE HYDROXYAPATITE COMPOSITES WITH POTENTIAL APPLICATION IN BONE TISSUE ENGINEERING – PHYSICOCHEMICAL ANALYSIS

SYNTHESIS AND APPLICATION OF CHITOSAN HYDROXYAPATITE: A REVIEW