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1

Properties of hydroxyapatite layers used for implant coatings

100%

Dudek A. , Adamczyk L.

Optica Applicata

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2013

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tom Vol. 43, nr 1

143--151

EN

Metallic materials such as titanium and titanium alloy generally show good mechanical properties but their biocompatibility is limited. In order to manufacture implants which combine improved mechanical properties of metallic material with biotolerance of ceramics, hydroxyapatite coatings are applied. In this paper, plasma sprayed coatings (deposited on titanium Ti–6Al– 4V ELI alloy) were analysed. The phase composition of hydroxyapatite (HA) coatings can be determined using a number of methods. The most commonly used are Joel 5400 scanning microscope, scratch test, X-ray diffraction and Raman. The increase of the zirconium and aluminium phase significantly affects the coating adhesion, estimated by the scratch test technique.

2

Przemiany hydroksyapatytu pochodzenia naturalnego w podwyższonych temperaturach i wybranych atmosferach

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Haberko K. , Bućko M. M. , Mozgawa W. , Haberko M. , Pyda A. , Carpentier J.

Inżynieria Biomateriałów

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2006

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tom R. 9, nr 58-60

35-35

PL

Ostatnie nasze badania wskazały na istotne różnice pomiędzy syntetycznym hydroksyapatytem (HAp) a materiałem wyekstrahowanym z kości zwierzęcych. Ten ostatni jest niestechiometryczny: stosunek Ca do P jest większy, od 1,67, co jest wartością charakterystyczną dla stechiometrycznego HAp. Ponadto hydroksyapatyt pochodzenia naturalnego zawiera grupy CO3(-2) oraz niewielki udział Mg. Oba te składniki są wbudowane w strukturę HAp. Są to cechy występujące w materiale z kości świńskich, wołowych a także ludzkich. Opracowano metodę ekstrakcji naturalnego hydroksyapatytu z korowej części zwierzęcych kości długich. Aby uzyskać z tego materiału kształtki użyteczne do badań biologicznych i zastosowań medycznych należy go poddać obróbce cieplnej w toku której zachodzi proces spiekania nadający wyrobom pożądane cechy mechaniczne. Stwierdzono jednakże, iż w podwyższonych temperaturach, począwszy od około 700 stopni Celsjusza podlega rozkładowi. Wydzielanie się z materiału CO2 wskazuje na zmniejszanie się w nim udziału grup CO3(-2). Potwierdzenie tego wniosku uzyskano poprzez pomiary metodą spektroskopii w podczerwieni. Pojawia się również wolny tlenek wapnia (CaO). Jakkolwiek pozostała część układu zachowuje nadal strukturę hydroksyapatytu, to obecność wolnego CaO dyskwalifikuje materiał do zastosowań biologicznych i medycznych. Przedmiotem niniejszej pracy były badania nad zachowaniem się hydroksyapatytu w temperaturach do 1000 stopni Celsjusza w atmosferze tlenu i CO2 (suchego i nasyconego parą wodną). Otrzymane próbki poddano analizie chemicznej, badaniom metodą dyfrakcji rentgenowskiej i metodą spektroskopii w podczerwieni. Stwierdzono, że atmosfera CO2 (zarówno suchego jak i nasyconego parą H2O) hamuje rozkład hydroksyapatytu: w próbkach preparowanych w ten sposób nie pojawia się wolny tlenek wapniowy. Równocześnie w temperaturach >900 stopni Celsjusza udział grup CO3(-2) w strukturze materiału nawet wzrasta. W przeciwieństwie do tego w atmosferze tlenu obserwuje się wydzielanie wolnego tlenku wapnia i ubytek udziału grup CO3(-2), podobnie jak poprzednio w atmosferze powietrza. W wyniku opisanej pracy stało się możliwe przygotowanie próbek użytecznych do badań nad zachowaniem się hydroksyapatytu pochodzenia naturalnego w środowisku biologicznym.

EN

Our previous investigations show essential difference between synthetic hydroxyapatite (HAp) and the material which occurs in animal bones. The latter one is non-stoichiometric; its Ca/P ratio in higher than 1.67, contains carbonate groups (CO3(-2)) and usually some Mg built into the HAp structure. This is a mutual feature of the material extracted from bovine, pig and human bones. A method of extracting HAp from animal cortical bones was elaborated. Application of such material involves subjecting it to the treatment et elevated temperatures in order to prepare useful shapes for biological and medical purposes. However it was found that the material decomposes starting from about 700 degrees of Celsius; emission of CO2 indicates the decrease in the CO3(-2) groups content. It was confirmed by IR measurements. Some free CaO also appears. Although the remaining material retains the HAp structure, the process of its decomposition is detrimental from the point of view of biological applications of the material or at least limits them. In the present work the behavior of HAp extracted from pig bones at elevated temperatures up to 1000 degrees of Celsius in O2 and CO2 (wet and dry) atmospheres was studied. Chemical analysis, X-ray diffraction and IR spectroscopy were useful to study changes in the material structure during processing. It was found that CO2 (dry and wet) atmosphere arrests HAp decomposition. At sufficiently high temperatures (>900 degrees of Celsius) concentration of CO3(-2) groups even increases. No free CaO appears. In contrast to that in oxygen atmosphere decomposition of HAp occurs, as it was previously observed in air atmosphere. Results of this work allow manufacturing samples useful for biological investigations.

3

Naturalny hydroksyapatyt - właściwości, zmiany podczas ogrzewania

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Haberko K. , Bućko M. M. , Brzezińska-Miecznik J. , Haberko M. , Mozgawa W. , Panz T. , Pyda A. , Zarębski J.

Materiały Ceramiczne

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2004

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tom R. 56, nr 3

93-97

PL

Naturalny hydroksyapatyt ekstrahowano z kości zwierzęcych drogą ich traktowania gorącym roztworem Na-OH. Pozostająca po tej obróbce część organiczną kości utleniono w umiarkowanych temperaturach w warunkach ogrzewania preparatu w atmosferze powietrza. Pozostający po tej obróbce materiał wykazywał obecność grup węglanowych i niewielkiej ilości magnezu. Stosunek Ca/P w materiale świńskiej kości korowej był wyraźnie wyższy niż w stechiometrycznym hydroksyapatycie. Udział grup węglanowych zmniejszał się ze wzrostem temperatury prażenia. Równocześnie pojawiał się wolny tlenek wapnia (CaO). Pomimo tego struktura charakterystyczna dla hydroksyapatytu została zachowana. Transmisyjna mikroskopia elektronowa pokazała, że uzyskany opisaną drogą hydroksyapatyt ma postać krystalitów o rozmiarach mniejszych od 20 nm. Intensywny rozrost tych krystalitów obserwuje się w temperaturach > 750 stopni C. Równocześnie wypraski z tego materiału wyraźnie się kurczą.

EN

Natural origin hydroxyapatite (HAp) was extracted from animal bones by their treatment with hot NaOH solution. The remaining organic matter oxidizes in air atmosphere at moderate temperatures. In the material of this kind carbonate groups and small amounts of magnesium were found. Ca/P ratio in pig cortical bones was higher than in the stoichiometric HAp. Fraction of carbonate groups decreases with temperature and CaO appears at higher temperatures, but structure of hydroxyapatite becomes preserved. Transmission electron microscopy showed that natural HAp powders consisted of nanosized crystallites (<20 nm). Crystallite growth becomes intensive at temperatures >750 Celsius degrees and simultaneously compacts of such powder show large shrinkage.

4

Alginate-based hydrogels modified with graphene oxide and hydroxyapatite for cartilage tissue regeneration

80%

Lach A. , Skoczeń M. , Ordon K. , Pielichowska K.

Engineering of Biomaterials

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2018

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tom Vol. 21, no. 148

52

5

Bioactive hydroxyapatite ceramics as scaffolds for bone tissue engineering – a preliminary study

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Soukup D. , Horakova D. , Sumberova H. , Andertova J. , Bacakova M. , Bacakova L.

Engineering of Biomaterials

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2011

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tom Vol. 14, no. 106-108

13--16

6

Ceramic-polymer composites with nano hydroxyapatite for orthopedic implants

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Dabrowska S. , Pietrzykowska E. , Chodara A. , Mukhovskyi R. , Chudoba T. , Locs J. , Lojkowski W.

Engineering of Biomaterials

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2016

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tom Vol. 19, no. 138 spec. iss.

117

7

Polyoxymethylene homo- and copolymer composites stabilized with PEG-grafted hydroxyapatite

80%

Król K. , Pielichowska K.

Engineering of Biomaterials

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2016

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tom Vol. 19, no. 138 spec. iss.

84

8

Fabrication of Bioactive Carbon Nonwovens for Bone Tissue Regeneration

80%

Rajzer I. , Grzybowska-Pietras J. , Janicki J.

Fibres & Textiles in Eastern Europe

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2011

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tom Vol. 19, no. 1 (84)

66-72

EN

The aim of tissue engineering is to repair or replace the function of defective or damaged tissue. One of the key factors is the creation of a scaffold as an artifcial extracellular matrix (ECM) for cellular attachment, proliferation and differentiation. In scaffold-based bone tissue engineering, both the porosity and mechanical properties of the scaffold are of great importance. To mimic the structure of natural ECM, three fbrous scaffolds based on composite carbon fbres containing nanohydroxyapatite were fabricated using nonwoven techniques. The overall objective of the present work was to compare and analyse the properties of needlepunched nonwoven produced from PAN and PAN/HAp fbres before and after stabilization and carboniation processes. The characterisation of the scaffold showed that after the carbonisation process, the nonwoven had an interconnective microporous structure (70-150 žm), high porosity as well as mechanical and structural integrity. Soaking the nonwoven in simulated body fuid (SBF) at body temperature formed a bone-like apatite on the fbre surface. The formation of the bone-like apatite demonstrates the potential of nonwovens for integration with bone.

9

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

80%

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

Polish Journal of Chemical Technology

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2008

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tom 10

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nr 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.

10

EPR study on biominerals as materials for retrospective dosimetry

80%

Sadło J. , Michalik J. , Stachowicz W. , Strzelczak G. , Dziedzic-Gocławska A. , Ostrowski K.

Nukleonika

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2006

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tom Vol. 51,suppl.1

95-100

EN

Stable paramagnetic species, induced by irradiation in biominerals, can be successfully used as an EPR dosimeter in numerous domains of scientific activity. In hydroxyapatite, the main mineral component of bones, the most stable signal is assigned to CO2 - ion radical. The signal is dose dependent and allows to determine the absorbed dose in a wide range till 20 kGy, with detection limit for tooth enamel below 1 Gy. The additive dose method was applied to EPR dating of archeological objects and EPR dosimetry after accidental overexposing during radiotherapy. It was found that the age of remains excavated from the “tomb of giants” belonging to Nuraghic culture developed in Sardinia island is about 3160 years old (1160 years BC). The dose obtained by patients during the accident at the Białystok Oncological Center was evaluated at about 75 Gy. Searching for potential dosimeters among other biominerals shows that mollusc shells have very promising properties. The lowest dose detection limit was found for an Arcidae shell. Both fresh water and sea mollusc shells are useful to be used for dosimetry in the low dose range.

11

Effect of retardants on the heat release during setting of bone cement-type composites

80%

Pijocha D. , Łój G. , Nocuń-Wczelik W. , Ślósarczyk A.

Journal of Achievements in Materials and Manufacturing Engineering

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2011

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tom Vol. 49, nr 2

204--209

EN

Purpose: The aim of this work was to investigate the influence of retardants on the heat release during setting of the new hydroxyapatite (HA) - magnesium phosphate cement (MPC) - calcium sulphate hemihydrate (CSH) composites. Design/methodology/approach: We used the calorimetric method to measure the temperature effect of setting reaction in these new composites. Microstructure observations by means of scanning electron microscopy was also performed. Findings: The decrease in maximum temperature reached during hardening process with use of different retardants was confirmed. Research limitations/implications: Biological evaluation and in vitro physico-chemical tests of the novel composites need to be done. Practical implications: The highly exothermic setting reaction of cement composites based on MPC can be lowered to avoid harmful necrosis of the tissues surrounding the implant material. Originality/value: Detailed studies on the heat release during setting of HA - MPC - CSH composites were performed for a first time, giving an opportunity to choose the best composition for further studies.

12

Carbonate-Containing barium Hydroxyapatite Synthesized by Solid State Reactions

80%

Getman E. , Loboda S. , Ignatov A. , Demchenko P.

Polish Journal of Chemistry

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2004

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tom Vol. 78 / nr 1

35-43

EN

The carbonate-containing barium hydroxyapatite was prepared by solid state reactions in air at 950°C. Obtained samples were investigated by X-ray powder diffraction and IR spectroscopy. The stoichiometry of these samples conforms to Ba5(PO4)3-x(CO3)x(OH)1-xOx as the result of CO3 2 and O2- substitution for PO4 3 and OH- in the hydroxyapatite lattice under the scheme: PO4 3 + OH- _ CO3 2 + O2-. The crystal structure of some carbonated barium hydroxyapatite patterns were refined by Rietveld method using X-ray powder diffraction data. The analysis of the crystallographic site occupation has shown that the single phase range of Ba5(PO4)3-x(CO3)x(OH)1-xOx is limited by x = 0.32.

13

Modification of hydroxyapatite as a filler for PMMA bone cements

80%

Rejs K. , Laska-Leśniewicz A. , Szymanowski H. , Niedzielski P. , Sobczyk-Guzenda A.

Engineering of Biomaterials

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2018

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tom Vol. 21, no. 148

37

14

Kinetic and equilibrium studies on adsorption of Reactive Blue 19 dye from aqueous solutions by nanohydroxyapatite adsorbent

80%

Ciobanu G. , Barna S. , Harja M.

Archives of Environmental Protection

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2016

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tom Vol. 42, no. 2

3--11

EN

In the present study the adsorption of Reactive Blue 19 dye on the hydroxyapatite (HAp) nanopowders was investigated. The batch adsorption experiments were performed by monitoring the adsorbent dosage, contact time, dye solution concentration, pH and temperature. At pH 3 and 20ºC, high dye removal rates of about 95.58% and 86.95% for the uncalcined and calcined nanohydroxyapatites, respectively, were obtained. The kinetic studies indicated the dye adsorption onto nanohydroxyapatite samples to follow a pseudo-second order model. The Langmuir isotherm was found to be the best to represent the equilibrium with experimental data. The maximum adsorption capacity of uncalcined and calcined nanohydroxyapatite samples has been found to be 90.09 mg/g and 74.97 mg/g, respectively.

15

Synthesis and characterization of hydroxyapatite/chitosan composites

80%

Szatkowski T. , Kołodziejczak-Radzimska A. , Zdarta J. , Szwarc-Rzepka K. , Paukszta D. , Wysokowski M. , Ehrlich H. , Jesionowski T.

Physicochemical Problems of Mineral Processing

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2015

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tom Vol. 51, iss. 2

575--585

EN

Hydroxyapatite (HAp)/chitosan (CS) composites were synthesized via a one-step co-precipitation method from aqueous solution, with the use of calcium chloride (CaCl2) and disodium hydrogen phosphate (Na2HPO4). CS was obtained via partial deacetylation of chitin with the use of strong sodium hydroxide solution. Composites were prepared with various HAp/CS ratios (30/70, 50/50, 70/30, 85/15) for comprehensive comparison of their properties. Fourier Transform Infrared Spectroscopy (FT-IR) analysis showed that hydrogen bonds were formed between the organic matrix and the mineral compound, confirming a successful phase interconnection. X-ray diffraction patterns were obtained, enabling examination of the crystalline properties of the composites, including HAp identification. The porous structure parameters of the composites were investigated, and morphological analysis (SEM) was performed. Differential Thermal Gravimetry (DTG) analysis of the composites indicated that the material is thermally stable up to 200 oC. Additionally, Energy Dispersive Spectroscopy (EDS) analysis of the mineral was carried out to check the Ca/P ratio, and confirmed its similarity to pure HAp.

16

The properties of nanosilver – doped nanohydroxyapatite coating

80%

Bartmański M.

Engineering of Biomaterials

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2018

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tom Vol. 21, no. 148

74

17

Bioapatite made from chicken femur bone

80%

Supova M. , Simha-Martynkova G. , Sucharda Z. , Suchy T.

Engineering of Biomaterials

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2011

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tom Vol. 14, no. 109-111 spec. iss.

11--13

18

FEM approach to estimate the behaviour of biocomposite metal-surface coating systems

80%

Sobieszczyk S. , Wojnicz W. , Nowak B.

Advances in Materials Science

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2008

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tom Vol. 8, nr 1(15)

153-158

EN

A three dimensional (3D) model of biocomposite metal-surface coating system, which is influenced by known external forces, is proposed. This model consists of the metallic substrate (Ti6AI4V) and the hydroxyapatite (HA) coating. Using FEM (finite element method), strain-stress maps of model were generated for investigating rela-tions between the extreme stress of HA coating and the magnitude of external force and the thickness of the coat-ing. The analysis of numerical simulations results confirms that the system with the greatest coating thickness (i.e. 10-3 m) has the least extreme stress in this surface coating.

19

Hydroxyapatite - chitosan material with silver nanoparticles

80%

Zima A. , Czechowska J. , Cichoń E. , Ślósarczyk A.

Engineering of Biomaterials

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2018

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tom Vol. 21, no. 148

57

20

Sposób wytwarzania materiałów o kontrolowanej porowatości z hydroksyapatytu przy wykorzystaniu metody Robocasting

80%

Gryń K. , Chłopek J. , Saiz E. , Tomsia A. P.

Engineering of Biomaterials

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2007

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tom Vol. 10, no. 62

26-29

PL

W artykule przedstawiono nowatorską metodę umożliwiającą wytwarzanie struktur przestrzennych - Robocasting (drukowanie przestrzenne) do budowania bioceramicznych porowatych materiałów implantacyjnych. Celem prowadzonych badań jest wytworzenie idealnie dopasowanego implantu do konkretnego pacjenta pod względem budowy, struktury i funkcji. Takie wszczepy mogą być wykorzystane np. : w chirurgii rekonstrukcyjnej - ubytki tkanki kostnej będące następstwem zmian nowotworowych, urazowych itp. Zaprezentowano sposób przygotowania materiału wsadowego poprzez przeprowadzenie proszku ceramicznego do postaci gęstej mieszaniny - pasty. W badaniach użyto proszku hydroksyapatytu jako najbardziej odpowiedniego do zastosowań medycznych. Przy pomocy omawianej techniki wydrukowano kilka rodzajów próbek, które poddano procesowi wypalania. Pokazano wyniki wstępnych badań strukturalnych.

EN

In the article novel rapid prototyping technique - Robocasting - as a method for porous bioceramic scaffolds assembling is presented. The research of focused on personalized implant fabrication individually designed for a specific patient (shape, structure, properties, biocompatibility). For the base material hydroxyapatite was chosen because of its possible medical application. Plastic or reconstructive surgery is a field of potential use of such implants (neoplasm of the bone, destroyed bone tissue after injuries, etc.). For printing purpose a special feedstock is necessary. A preparation of a dense slurry containing ceramic powder (the paste/ink) is described. Different shapes and sizes of hydroxyapatite scaffolds were printed, fired and tested.