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1

Preparation of composite filaments and 3D prints based on PLA modified with carbon materials with the potential applications in tissue engineering

Hunger M., Podgórny W., Frączek-Szczypta A.

Engineering of Biomaterials

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2018

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Vol. 21, no. 147

7--15

EN

This paper discusses the possibilities of obtaining polylactide-based composites and nanocomposites modified with carbon materials using the extrusion method, as well as the potential of their application in 3D printing technology. The aim of this research is to determine the impact of the presence of carbon additives on the properties of composites: mechanical, thermal and chemical. For this purpose, several research techniques were used such as scanning electron microscopy (SEM), X-ray photoelectron spectroscopy (XPS), DSC/TG analysis, infrared Fourier-transform infrared spectroscopy (FTIR) and mechanical tests. It has been shown that it is possible to effectively produce composite materials based on PLA and carbon modifiers after optimization of the extrusion and printing process. Special attention should be paid to the quality of carbon phases homogenization in PLA matrix because the inappropriate dispersion may have a negative effect on the final properties of the composite, especially those modified with nanomaterials. Moreover, the reinforcing effect of carbon phases can be observed, and the quality of obtained filament with carbon fiber after recycling does not differ significantly from the quality of commercially available filaments. The obtained filament was successfully used to print three-dimensional scaffolds. Therefore, both the use of materials which are biodegradable and biocompatible with human tissue and the 3D printing method have the potential to be applied in tissue engineering.

2

Effect of surface titanum modification on interaction with graphene oxide coatings

Frączek-Szczypta A., Kluska S., Młynarska P.

Engineering of Biomaterials

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2017

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Vol. 20, no. 143 spec. iss.

70

3

The influence of different types of carbon nanomaterial on the properties of coatings obtained by EPD process

Wedel-Grzenda A., Tran K., Frączek-Szczypta A.

Engineering of Biomaterials

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2016

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Vol. 19, no. 135

13--20

EN

The first part of research is concentrated on the examination of four kinds of carbon nanomaterials: graphene oxide (GO), multi-walled carbon nanotubes (MWCNT), multi-walled carbon nanotubes functionalized by authors in acids mixture (MWCNT-F) and multi-walled carbon nanotubes with hydroxyl groups (MWCNT-OH). Their microstructure was observed in transmission electron microscopy (TEM). Based on these microphotographs, the diameters of carbon nanotubes were measured. Then, in order to determine the chemical composition of GO, MWCNT-F and MWCNT-OH, X-ray photoelectron spectroscopy was applied. The second part of study concerns the properties of the coatings deposited electrophoretically on titanium surface from previously examined nanomaterials. The coatings from individual nanomaterials, as well as hybrid layers (combination of two kinds of nanomaterial: graphene oxide with one of the nanotubes’ type) were deposited. Microstructure of the coatings was evaluated with the use of scanning electron microscopy (SEM). Furthermore, surface properties, important while considering usage of these materials in biological applications: wettability and surface free energy were evaluated. These materials are meant for application in regeneration and stimulation of nerve cells. All the research carried out so far indicate the influence of nanotubes’ functionalization degree on the properties of their suspension, as well as the characteristics of the deposited coating. It also influences the interaction between two types of nanomaterials. Functionalization in strong acids introduces functional groups which change nanotubes’ dimensions, properties and behavior in solution.

4

Influence of microstructure and chemistry of carbon nanomaterials coatings on nerve cells

Frączek-Szczypta A., Wedel-Grzenda A., Jantas D.

Engineering of Biomaterials

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2016

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Vol. 19, no. 138 spec. iss.

119

5

Otrzymywanie nanorurek węglowych na podłożach metalicznych i kwarcowych metodą CVD

Frączek-Szczypta A., Spisak M., Błażewicz S.

Przemysł Chemiczny

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2012

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T. 91, nr 6

1191-1198

PL

Przedstawiono wyniki badań nad otrzymywaniem nanorurek węglowych (CNT) metodą chemicznego osadzania z fazy gazowej na stali nierdzewnej oraz na kwarcu. Podłoża stalowe nie wymagały stosowania dodatkowej procedury związanej z nanoszeniem katalizatora metalicznego, niezbędnego do krystalizacji węgla w postaci nanorurek. Dla podłoża kwarcowego jako katalizator stosowano żelazo. Opisano sposób przygotowania powierzchni podłoży, warunki doświadczalne otrzymywania CNT z acetylenu i uzyskane wyniki. Podłoża i osady węglowe badano stosując mikroskopię skaningową (SEM), optyczną i spektroskopię rentgenowską z dyspersją energii (EDS). Porównano efektywność wzrostu nanorurek na obu podłożach i określono korzystne zakresy temperaturowe do ich krystalizacji. Badania wykazały, że na podłożu stalowym nanorurki węglowe powstawały w zakresie temperatur 700–800°C. Wzrost nanorurek węglowych na podłożu kwarcowym poprzedzony był tworzeniem się warstwy węgla pirolitycznego. Na warstwie tej wzrastały nanorurki węglowe. Po schłodzeniu reaktora warstwa ta wraz z nanorurkami nie przylegała do powierzchni kwarcu. Taki mechanizm zaobserwowano dla osadów węglowych na powierzchni kwarcowej otrzymanych w temp. 750°C.

EN

C nanotubes were produced on stainless steel and quartz substrates by CVD using CH≡CH at 700–800°C and studied for microstructure and surface roughness. Fe(NO₃)₃ was used as catalyst on the quartz substrate. Formation of mono and multiwall tubes was obsd.

6

Polylactide - carbon nanotubes nanocomposites as membranes for guided nerve regeneration (GNR)

Stodolak-Zych E., Frączek-Szczypta A., Błażewicz M.

Engineering of Biomaterials

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2012

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Vol. 15, no. 116-117 spec. iss.

139--140

EN

New generation of membrane materials can play role in regeneration process in living organism e.g. creation of optimal conditions for regeneration of bone tissue (GBR/GTR technique) or defected peripheral nerve (GNR technique). However, biodegradable polymeric materials which are now widely used in GNR technique (PLA, PCL, collagen) does not have satisfactory mechanical properties such as strength (RM) or Young's modulus (E) because it is difficult to control their porosity [1,2]. Materials suitable for nerve regeneration should exhibit electrical properties which stimulate the regeneration [3]. The main idea of the guided nerve regeneration is utilisation of a membrane separating two tissues i.e. defected nerve tissue and connective tissue. Inside the defected nerve tissue surrounded by the membrane should be present factors influencing the regeneration process such as: ECM protein, nervotrofic factors. On the other hand, the membrane should act as a barrier for fibroblast cells inflowing into the defected area. The work presents results of investigations on porous nanocomposite materials basing on bioresorbable aliphatic polyesters i.e. poly-(L/DL)-lactide and carbon nanotubes (CNT). All materials i.e. nanocomposite foils and porous materials were prepared using synthetic co-polymer of L/DL-lactide with L/DL ratio of 80/20 from Purac®. The polymer had the FDA attestation confirming its biocompability. As the nanofillers, two types of CNTs produced by Nanostructured and Amorphous Materials (Inc. Huston, USA) were used: MWCNTs (multi-wall carbon nanotubes; diameter 10-30 nm and length 1-2 μm) and SWCNTs (single-wall carbon nanotubes; diameter 0.7-2 nm and length 15-30 μm). Nanocomposite membrane materials (PLDLA/0.5% wt. MWCNTs and PLDLA/0.5% wt. SWCNTs) were prepared using combined methods: phase inversion and freeze-drying. Porous microstructure of the nanocomposites was investigated using SEM/EDS. It was found, that the presence of the CNT influenced shape, size (5-50 μm) and distribution of pores in the material (total porosity of PLDLA/ MWCNTs was about ~65% and PLDLA/S WCNTs was about ~35%). The nanoadditives increased mechanical properties of the membrane materials. For example addtition of the SWCNTs increased the membrane strength (RM) form 16 to 24 MPa. Physicochemical properties of the materials surface were investigated by means of wettability and surface energy measurements. It was shown that dispersion part of surface free energy decreased when SWCNTs were used as additives (from 4.5 mm/mJ PLDLA membrane to 0.7 mm/mJ PLDLA/SWCNTs), while in the case of the MWCNTs addition dispersion part of surface energy increased from 4.5 mm/mJ to 6.9 mm/mJ. Such PLDLA-based materials modified with CNTs (MWCNTs, SWCNTs) may be an attractive support for adhering cells. SWCNTs were more suitable nanoad- ditives for PLDLA-matrix membranes than MWCNTs, because such membranes were stronger, hydrophilic and much more bioactive.

7

In vitro studies of different types of carbon nanotubes deposited on PTFE membrane

Frączek-Szczypta A., Menaszek E., Miranowicz M., Błażewicz S.

Engineering of Biomaterials

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2012

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Vol. 15, no. 116-117 spec. iss.

153--154

8

Preliminary investigation of alginate fibers modified with magnetite

Frączek-Szczypta A., Piecek A., Boguń M., Błażewicz S.

Engineering of Biomaterials

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2011

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Vol. 14, no. 106-108

17--20

EN

In this work alginate nanocomposite fibers modified with magnetite were investigated as prospective material for bone tissue regeneration after tumor resection. In the first stage of the research the morphology of composite fibers and their chemical composition were evaluated. Determination of the mechanical properties of the nanocomposite materials indicated that magnetite does not improve the strength of the nanocomposites. A slight increase of Young’s modulus was observed only for composite fibers with a lower concentration of nanoadditive. Weekly and monthly incubation of fibers in distilled water indicates the release of magnetite from the material. This result is optimistic in terms of the applicability of these materials, not only for tissue regeneration, but also to destroy cancer cells using the external magnetic field.

9

Nanokompozyty polimerowe do zastosowań medycznych

Stodolak E., Frączek-Szczypta A., Błażewicz M.

Kompozyty

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2010

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R. 10, nr 4

322-327

PL

Praca obejmuje badania nad biozgodnymi polimerami modyfikowanymi nanocząstkami ceramicznymi. Przedmiotem badań były nanokompozyty polimerowe, wytworzone z trzech różnych polimerów: polimeru biostabilnego (polisulfon - PSU), polimeru resorbowalnego (poli(L/DL)laktyd - PL(L/DL)A) oraz polimeru pochodzenia naturalnego (chitozan - CS). Jako modyfikatory zastosowano nanometryczne cząstki ceramiczne: montmorylonit (MMT), krzemionkę (SiO2) oraz nanorurki węglowe (CNT). Materiały nanokompozytowe zostały scharakteryzowane pod względem parametrów biologicznych i mechanicznych. Wyniki badań wskazują, że modyfikacja wszystkich trzech grup polimerów, przy zastosowaniu nanocząstek ceramicznych, to skuteczna droga do otrzymywania biozgodnych, bioaktywnych tworzyw, posiadających dodatkowo znacznie lepsze parametry mechaniczne w porównaniu z czystymi polimerami.

EN

Nanotechnology generally bases on modification of materials' behaviour. One of the first real products of nanotechnology is polymer nanocomposites, which are a combination of polymer matrix and nanoparticles (so called nanofillers) that have at least one dimension in a nanometric range. The nanofillers such as nanopowders, nanofibers, or nanotubes modify the polymer matrix on a molecular level. Properties of such materials depend both, on the matrix, and the nanoparticles. These materials may exhibit enhanced mechanical (tensile strength, stiffness, toughness), gas barrier, thermal expansion, thermal conductivity, ablation resistance, optical properties, chemical properties, electronic and magnetic properties. Polymer nanocomposites is a promising class of hybrid materials derived from both synthetic and natural polymers and inorganic/organic nanoparticles. The introduction of nanoparticles into a polymer matrix ensures significant improvement of the material's properties. Polymer nanocomposites are of immense interest of such biomedical technologies as; tissue engineering, bone replacement, dental applications and controlled drug delivery. Current opportunities for application of polymer nanocomposites in biomedical applications arise from their tailored bioactivity, biodegrabilty, and mechanical properties. Interaction between nanofillers and a polymer matrix enables them to act as molecular bridges in the polymer structure. High adhesion of nanoparticles to the polymer matrix results in the enhanced strength and Young's modulus of the nanocomposites comparing to conventional composites. The paper presents results of our investigations on three kinds of nanocomposites basing on biocompatible polymer matrices and nanoparticles such as; MMT, SiO2 and CNTs which constitute temporary replacing materials in a missing bone tissue. Such material should be biocompatible, osteoinductive, osteoconductive and porous as well as mechanically compatible with the bone tissue. The results of biological investigations provided evidence of good adhesion, proliferation and morphology of osteoblastic cells on the surface of each polymer nanocomposites. The ability of the polymer nanocomposite to cell attachment, spreading and growth in in vitro conditions, combined with the good mechanical properties suggest potential use of these material as biomedical devices, particularly in the area of regenerative medicine. Values of Young's modulus increase in all nanocomposites, and their tensile strength depends on dispersion of the nanoparticles in the polymer matrix, and in most cases decrease because of agglomeration of the nanoparticles. Polymer nanocomposite containing bioactive nanoprticles shows osteoinductive properties. Treatment of the nanocomposite samples in the simulated body fluid (SBF) induced some changes on the surface of the material containing bioactive ceramic nanoparticles. The results of the tests with SBF show that the material is able to produce apatite structure on its surface.

10

Influence of formation conditions on the structure and properties of nanocomposite PAN fibres containing silver and hydroxyapatite nanoadditives

Mikołajczyk T., Szparaga G., Rabiej S., Frączek-Szczypta A.

Fibres & Textiles in Eastern Europe

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2010

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Vol. 18, no. 5 (82)

16--23

EN

An investigation was made into the influence of the temperature of a coagulation bath and value of the as-spun draw ratio on the porous structure and strength properties of PAN fibres containing two nanoadditives. With the presence of hydroxyapatite in nanocomposite fibres, the transformation of paracrystalline regions, existing in fibers without nanoadditives in a crystalline structure, is connected. Carbon fibres were obtained from nanocomposite fibres. The mechanical properties of the carbon fibres obtained are good enough for medical applications. Based on SEM and EDX analyses, it was found that both nanoadditives are evenly distributed on the surface of precursor and carbon fibres.

PL

W pracy zbadano wpływ temperatury kąpieli koagulacyjnej oraz wartości wyciągu filierowego na strukturę porowatą i właściwości wytrzymałościowe włókien PAN zawierających w tworzywie układ dwóch nanododatków. Z obecnością hydroksyapatytu we włóknach nanokompozytowych związana była przebudowa obszarów parakrystalicznych, obecnych we włóknach bez nanododatku, w strukturę krystaliczną. Z włókien nanokompozytowych otrzymano włókna węglowe. Właściwości mechaniczne otrzymanych włókien węglowych są wystarczające do zastosowań medycznych. Na podstawie analizy SEM+EDS stwierdzono, iż oba nanododatki są dość równomiernie rozmieszczone na powierzchni włókien prekursorowych i węglowych.

11

Preliminary investigations of polylactide-based nanocomposites as potential materials for bone cells proliferation

Frączek-Szczypta A., Stodolak E., Wiecheć A., Błażewicz M.

Engineering of Biomaterials

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2010

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Vol. 13, no. 96-98

1--3

EN

Nanocomposite materials can be used in many application. In this study polymer–based nanocomposites modified with carbon nanotubes (CNTs) and ceramic silica nanoparticles (nSiO2) were used. Size and shape of nanoparticles were observed using transmission electron microscope (TEM). It was shown that, this parameter changes during mixing of nanoparticles with solvent or polymer solution. Dispersion of nanoparticles depends on their chemical composition. The CNTs are more compatible with polymer (PLDL) than nSiO2. Nanoparticles influence rheological parameters of the polymer solution (increase of viscosity). Distribution of nanoparticles within the polymer matrix was determined using DLS method. Nanocomposites in the form of thin foils were used for mechanical tests which show that small amount of nanoparticles increases tensile strength (Rm) and Young’s modulus (E) of the material. The biological properties of the polymer-based nanocomposite materials like viability and proliferation were measured using osteoblast-like human cells MG63. Results of these investigations show that both types of the nanocomposites are suitable for promoting bone tissue for faster regeneration process.