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1

Investigation of antibacterial properties of ceramic substrates coated with calcium phosphate and polymeric nanoparticles loaded with antibiotics

Marszałek Anna, Pudełko-Prażuch Iwona, Krok-Borkowicz Małgorzata

Engineering of Biomaterials

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2023

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vol. 26, no. 169

11--17

EN

This study investigates a biomimetic method of deposition of bioactive calcium phosphate (CaP) layers on zirconium oxide substrates (ZrO2). The substrates contained polymer nanoparticles of poly(L-lactide-co-glycolide) (PLGA) obtained using the double emulsion method with solvent evaporation. Three antibiotics were encapsulated within the nanoparticles: bacitracin, gentamicin sulphate, and hydrophobic gentamicin, prepared with the use of the ion pairing method. Nanoparticles were immobilized on the substrates using the drop casting or the co-deposition method. The microstructure of the layers and the distribution of the nanoparticles were assessed by scanning electron microscopy. The nanoparticles size and their zeta potential were measured using the dynamic light scattering method. The release of drugs over time was examined and the antibacterial properties were evaluated in contact with Staphylococcus aureus bacteria using the spectrophotometric method and the Kirby-Bauer test. The results show that the layer deposition method is effective and allows to obtain homogenous bioactive coatings. Nanoparticles were agglomerated on the surface or homogenously distributed in the CaP coating, depending on the process used to immobilize them. The drug release profile and antibacterial properties can also be modified by changing the process – the drop casting method allows to obtain a coating with a stronger antimicrobial effect and faster drug release. Nanoparticles obtained by the double emulsion method with solvent evaporation have the required size to be immobilized between the CaP crystallites. Additionally, the encapsulation of drugs decreased the zeta potential of the nanoparticles, which was caused by the interaction of the drug and the polymer. Nanoparticles loaded with bacitracin showed weak antibacterial properties, as the growth inhibition zone in the Kirby-Bauer test was barely visible. Two other types of nanoparticles exhibited good antibacterial properties, exceptionally strong for those loaded with hydrophobic gentamicin

2

Poly lactic-co-glycolic acid (PLGA) as biodegradable layer used in cardiology

Hyla A., Walke W., Kajzer W., Basiaga M., Paszenda Z.

Engineering of Biomaterials

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2018

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Vol. 21, no. 148

110

3

Modification of poly(lactic acid) (PLA) and poly(lactide-co-glycolide) (PLGA) fibres by ceramic particles

Król P., Boguń M.

Engineering of Biomaterials

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2018

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Vol. 21, no. 148

113

4

The comparative study of influence of lactic and glycolic acids copolymers type on properties of daunorubicin loaded nanoparticles and drug release

Nikolskaya E., Sokol M., Faustova M., Zhunina O., Mollaev M., Yabbarov N., Tereshchenko O., Popov R., Severin E.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 1

65--77

EN

The aim of this study was to compare the physico-chemical and biological properties of polymeric nanoparticles obtained from poly(DL-lactide-co-glycolide) (PLGA) with different ratios of monomers loaded with daunorubicin (DNR). Methods: DNR-loaded nanoparticles (NPs) were prepared with use of modified simultaneous double-emulsion solvent evaporation/diffusion technique. NPs were characterized using dynamic light scattering, atomic force microscopy, transmission electron microscopy, scanning electron microscopy, and differential scanning calorimetry and Fourier transform infrared spectroscopy. Results: NPs with DNR were differing in size and zeta potential, depending on the type of polymer. The data obtained show that total content of DNR correlates with the values of the binding constant of DNR with polymers. The release of DNR from NPs proceeds predominantly for polymers with lower binding constants. The in vitro study of NPs on the MCF-7 cells showed similar activity of particles and substances while for the anthracycline-resistant MCF-7Adr cells the cytotoxicity of the nanoparticles was 3 to 7 times higher depending on the type of copolymer. Conclusions: PLGA DNR-loaded nanoparticles can be used to overcome multidrug resistance (MDR) as well as for reducing the frequency of DNR reception due to the prolonged effect, which allows maintaining the concentration of the drug at the required level. The usefulness of binding constant calculations for obtaining nanoparticles with the maximum drug loading was proven. The rate of drug administration and the frequency of administration can be calculated based on the DNR release profiles and release parameters that depend on polymer type.

5

One step 3D printing of surface functionalized composite scaffolds for tissue engineering applications

Kotlarz M., Jordan R., Wegner E., Dobrzyński P., Neunzehn J., Lederer A., Wolf-Brandstetter C., Pamula E., Scharnweber D.

Acta of Bioengineering and Biomechanics

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2018

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Vol. 20, no. 2

35--45

EN

A successful approach widely used in materials science to adapt approved materials to specific applications is to design their surface properties. A main challenge in this area is the development of processing routes enabling for a simple but efficient surface design of complex shaped geometries. Against this background, this work aimed at the implementation of self-assembly principles for surface functionalization of 3D-printed poly(lactic-co-glycolic acid) (PLGA)-based constructs with macro- and microporous geometries via precision extruding deposition. Methods: Three-component melts from PLGA, CaCO3 and amphiphilic polymers (poly(2-oxazoline) block copolymer) were printed and their bulk and surface properties were studied. Results: Melts with up to 30 mass % of CaCO3 could be successfully printed with homogeneously distributed mineral particles. PLGA degradation during the printing process was temperature and time dependent: the molecular weight reached 10 to 15% of the initial values after ca. 120 min of heat exposure. Filament surfaces from melts containing CaCO3 show an increasing microroughness along with increasing CaCO3 content. Surface roughness and amphiphilic polymer content improve scaffold wettability with both factors showing synergistic effects. The CaCO3 content of the melts affected the inner filament structure during in vitro degradation in PBS, resulting in a homogeneous mineral particle-associated microporosity for mineral contents of 20 mass % and above. Conclusions: These results provide novel insights into the behavior of three-component melts from PLGA, CaCO3 and amphiphilic polymers during precision extruding deposition and show for the first time that self-assembly processes can be used to tailor scaffolds surface properties under such processing conditions.

6

Modification of PLGA microspheres’ microstructure for application as cell carriers in modular tissue engineering

Mielan B., Krok-Borkowicz M., Pielichowska K., Pamuła E.

Engineering of Biomaterials

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2017

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Vol. 20, no. 140

7--11

EN

Microspheres (MS) made of resorbable polymer have been proposed as a cell growth support. They may be assembled to form cell constructs or be suspended in hydrogels allowing injection into injury location. High relative surface area of MS provides more efficient cell culture environment than traditional culture on flat substrates (multiwell plates, Petri dishes). In addition, MS structure, topography and surface chemistry can be modified to promote cell adhesion and proliferation. The aim of this study was to obtain resorbable poly(L-lactide-co-glycolide) (PLGA) MS and to modify their properties by changing manufacturing conditions of the oil-in-water emulsification to better control structural and microstructural properties of MS and their biological performance. To this end, water phase was modified by addition of NaCl to change ionic strength, while oil phase by addition of polyethylene glycol (PEG). Microstructural and thermal properties were assessed. Cytocompatibility tests and cell cultures with MG-63 cells were conducted to verify potential relevance of MS as cell carriers. The results showed that it is possible to obtain cytocompatible MS by oil-in-water emulsification method and to control diameter, porosity and crystallinity of MS with the use of additives to oil and/or water phases without negative changes in MS cytocompatibility. The results prove that modification of both phases make it possible to produce MS with desired/controllable properties like surface topography, porosity and crystallinity.

7

Corrosion resistance of PLGA-coated biomaterials

Szewczenko J., Kajzer W., Grygiel-Pradelok M., Jaworska J., Jelonek K., Nowińska K., Gawliczek M., Libera M., Marcinkowski A., Kasperczyk J.

Acta of Bioengineering and Biomechanics

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2017

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Vol. 19, no. 1

173--179

EN

The aim of the study was to determine the influence of PLGA bioresorbable polymer coating on corrosion resistance of metal biomaterial. Polymer coating deposited by immersion method was applied. Corrosion resistance of metal biomaterials (stainless steel, Ti6Al4V, Ti6Al7Nb) coated with PLGA polymer, after 90 days exposure to Ringer’s solution was tested. The amount of metal ions released to the solution was also investigated (inductively coupled plasma–atomic emission spectrometry (ICP-AES) method). The surface of the samples was observed using atomic force microscopy (AFM) and scanning electron microscopy (SEM). Degradation of PLGA was monitored with the use of the 1 H NMR spectroscopy and GPC (Gel Permeation Chromatography). The studies were carried out for non-sterilized (NS) and sterilized (S) samples. Application of the polymer coating causes a reduction of release of metal ions to the solution. Depending on metal substrate different course of destruction of polymer layer was observed. After 90 days of incubation in Ringer’s solution polymer layer was highly degraded, however, the composition of copolymer (ratio of the comonomeric units in the chain) remained unchanged during the whole process, which suggests even degradation. The polymer layer reduced degradation kinetics of the metal substrate. Moreover, degradation process did not change surface morphology of metal substrate and did not disturb its integrity. The results obtained indicate that the applied polymer layer improves corrosion resistance of the alloys being investigated. Thus, the developed implants with bioresorbable coatings could be advantageous for medical applications.

8

Hydrolytic degradation of PLLA and PLGA with surface modified by CO2 laser – preliminary study

Tomanik M., Kobielarz M., Antończak A., Filipiak J., Pezowicz C.

Engineering of Biomaterials

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2016

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Vol. 19, no. 138 spec. iss.

96

9

Badanie własności mechanicznych powłoki polimerowej na podłożu ze stopu Ti6Al7Nb

Solarz J., Grygiel-Pradelok M., Kajzer W., Szewczenko J.

Aktualne Problemy Biomechaniki

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2016

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z. 10

69--74

PL

W pracy przedstawiono wpływ sposobu modyfikacji powierzchni stopu Ti6Al7Nb na własności mechaniczne naniesionej powłoki biodegradowalnego polimeru poli(D,L-laktyd-ko-glikolid) (PLGA). Zakres badań obejmował: pomiary chropowatości oraz obserwacje makroskopowe powierzchni metalowego podłoża oraz obserwacje powierzchni powłoki polimerowej, badanie adhezji do podłoża oraz ultrananotwardości. Badania wykazały istotny wpływ sposobu modyfikowania powierzchni podłoża ze stopu Ti6Al7Nb na własności mechaniczne powłoki polimeru PLGA.

EN

The study describes results of research influence of methods for modifying the surface of the Ti6Al7Nb alloy on the mechanical properties of the applied coating of biodegradable polymer poli(lactid-co-glicolic acid) (PLGA). The research included: assessment of the macroscopic surface of samples in the initial state and after applied polymer coating, measurements of surface roughness of the metal substrate, scratch test and ultrananohardness test. Research has shown a significant impact of used method of modifying metal substrate on mechanical properties of the PLGA coating. The analysis also showed dependence of adhesion polymer coating on roughness of the metal substrate.

10

Obrazowanie trójwymiarowych rusztowań kostnych zasiedlonych komórkami macierzystymi

Szlązak K., Chlanda A., Rębiś J., Idaszek J., Kublik Ż., Jaroszewicz J., Woźniak M. J., Święszkowski W.

Przetwórstwo Tworzyw

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2014

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[R.] 20, nr 1 (157)

100--109

PL

W pierwszym etapie niniejszej pracy wytworzono i zasiedlono agregatami komórek macierzystych innowacyjne biomateriały. Rusztowania wykonano z mieszaniny poli(3-hydroksymaślanu-ko-3-hydroksywalerianu) (PHBV), poli(L-laktydu-ko-glikolidu) (PLGA) oraz trójfosforanu wapnia (TCP). W drugim etapie pracy, scharakteryzowano wytworzone biomateriały wykorzystując techniki rentgenowskiej mikrotomografii komputerowej z użyciem środka kontrastującego. Poddano je także analizie powierzchniowej przy pomocy mikroskopu sił atomowych. Wyniki odniesiono do materiału referencyjnego, którym były rusztowania wykonane z PHBV i PLGA. Mikrotomografia komputerowa zapewniła wnikliwą ocenę struktury rusztowań kostnych. Oprócz obrazowania komórek macierzystych umożliwiła obserwację mikrostruktury w całej objętości badanego materiału w 3D. Kolejną techniką szeroko stosowaną do badań rusztowań polimerowych była mikroskopia sił atomowych. Umożliwiła ona wizualną ocenę topografii badanych materiałów oraz analizę ich chropowatości. Wytworzone rusztowania kostne miały odpowiednie parametry dla proliferacji komórek macierzystych. Wyniki niniejszej pracy wykazały, że tomografia komputerowa jest odpowiednim narzędziem do obrazowania komórek macierzystych zasiedlonych na porowatych biomateriałach. Dodatkowo stwierdzono, że specjalnie modyfikowane sondy skanujące umożliwiły dokładniejszy w stosunku do standardowych pomiar chropowatości powierzchni rusztowań.

EN

The first stage of this study involved the preparation and seeding of innovative biomaterials with stem cell Scaffolds through a mixture of poly (3-hydroxybutyrate-co-3-hydroksy-valerat) (PHBV), poly (L-lactide-co-glycolide) (PLGA) and tricalcium phosphate (TCP). In the second stage, biomaterials were characterized using a X-ray computed microtomography (CT) with a contrast agent. They were also subjected to surface analysis using atomic force microscopy. The results were compared to the reference material, of a PHBV/PLGA composite scaffold. The computed microtomography ensured rigorous assessment of the bone scaffold structure. Apart from stem cell imaging it also enabled the observation of the microstructure in the entire volume of the material in 3D. Another technique used to study polymeric scaffold was atomic force microscopy (AFM). It allowed for the visual assessment of the topography of the tested materials, as well as the analysis of their surface roughness. The tested bone scaffolds showed appropriate parameters for stem cell proliferation. The results of this study indicated that tomography is a suitable tool for the imaging of stem cell seeding on porous biomaterials. In addition, we couclude that specially modified scanning probes enabled more accurate surface roughness measurements.

11

Research concerning fabrication of fibrous osteoconductive PLGA/HAp nanocomposite material using the method of electrospinning from polymer solution

Krucińska I., Boguń M., Chrzanowska O., Chrzanowski M., Król P.

Autex Research Journal

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2013

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Vol. 13, no. 3

57--66

EN

The aim of the work was to obtain nano fibrous structures from biodegradable polymer with the addition of hydroxyapatite using electrospinning technique. Research was conducted with two types of solvent: dichloromethane and 50:50 mixture of dimethyl sulfoxide and dichloromethane. As a polymer a copolymer of L-lactide and glycolide (PLGA), commercial product with trade name Resomer®LG 824, was used. The preliminary electrospinning tests enabled to match optimal polymer solution concentration of tested samples. Rheological properties of all tested polymer solutions has been determined. Influence of electrospinning conditions and the type of solvent on macroscopic structure has been investigated.

12

Wytwarzanie porowatych rusztowań z poli(3-hydroksymaślanu-ko-3-hydroksywalerianu) za pomocą techniki szybkiego prototypowania

Kublik Ż., Idaszek J., Święszkowski W.

Engineering of Biomaterials

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2012

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

79--81

PL

Poli(3-hydroksymaślan-ko-3-hydroksywalerian) (PHBV) jest polimerem biodegradowalnym należącym do grupy poliestrów alifatycznych. Polimer ten jest termoplastem o wysokim wskaźniku szybkości płynięcia, co utrudnia jego przetwarzanie za pomocą wytłaczania. W przedstawionych badaniach wytworzono mieszankę PHBV z PLGA oraz wyznaczono jej masowy wskaźnik szybkości płynięcia (MFR). Dodatek PLGA obniżył MFR, co umożliwiło wytworzenie trójwymiarowego rusztowania za pomocą techniki szybkiego prototypowania.

EN

Poly (3-hydroxybutyrate-co-3-hydroxyvalerate) (PHBV) is a biodegradable polymer which belongs to a group of aliphatic polyesters. PHBV is a thermoplast with a relatively high melt flow index. This property makes it difficult to process by means of extrusion. In the present study we have prepared PHBV blended with PLGA and determined its melt flow rate (MFR). The addition of PLGA decreased MFR, which enabled fabrication of three-dimensional scaffold by means of Fused Deposition Modeling (FDM).

13

Shape memory process in resorbable polymers: effect on surface properties and cell adhesion

Costa A. M., Ferreira A. S., Posadowska U., Krok M., Smola A., Dobrzyński P., Pamuła E.

Engineering of Biomaterials

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2012

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Vol. 15, no. 114

8--11

EN

The objectives of this study were to confirm the shape memory behavior of two new bioresorbable terpolymers (L-lactide, glycolide, and trimethylene carbonate: L-PLGTMC and B-PLGTMC), to follow the influence of the shape memory process on their surface properties and to test their cytocompatibility using osteoblast-like cells. For this purpose, foils of both terpolymers were prepared. The terpolymers' ability to recover up to 92-93% of the memorized shape within 10 seconds was obtained. The influence of shape memory process on the surface properties was assessed by water contact angle (WCA) measurement and atomic force microscopy (AFM) and the results suggested that both terpolymers preserved the hydrophilicity after recovery and also that B-PLGTMC polymer was rougher than L-PLGTMC (about 9 folds more). The AFM pictures showed the presence of spherical shape hills on the B-PLGTMC foil surface which after the stretching procedure became oriented toward the direction of the applied load. The terpolymers were seeded on both sides (Top and Bottom faces) with human MG63 osteoblast-like cells. Cell viability was assessed after 1, 3 and 7 days, using MTT assay. Results revealed an increasing number of metabolically active cells with the incubation time, suggesting, together with nitric oxide (NO) level determination, the cytocompatibility of both terpolymers. Cell spreading and morphology were investigated by H&E staining and obtained results corresponded well with ones of MTT and NO.

14

Porównanie właściwości mechanicznych biodegradowalnych kompozytów podwójnych i potrójnych na osnowie PCL

Korzeb K., Idaszek J., Święszkowski W.

Engineering of Biomaterials

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2012

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

66--68

PL

Celem poniższych badań było porównanie właściwości mechanicznych włókien kompozytów polimerowo-ceramicznych na osnowie polikaprolaktonu (PCL) jako potencjalnego materiału do wytworzenia rusztowań do regeneracji ubytków tkanki kostnej w organizmie człowieka. Jako napełniacz wykorzystano mikro-cząstki trójfosforanu wapnia (TCP). Wytworzono również kompozyt potrójny zawierający dodatkowo kopolimer kwasu mlekowego i glikolowego (PLGA). Przeprowadzono próbę rozciągania oraz obserwację na skaningowym mikroskopie elektronowym. Wprowadzenie mikrocząstek TCP do osnowy PCL tylko w małym stopniu poprawiło właściwości mechaniczne kompozytów. Dopiero dodatek PLGA spowodował znaczy wzrost sztywności oraz podwyższenie granicy plastyczności.

EN

The aim of present study was to compare the mechanical properties of binary and ternary composite fibers fabricated by means of combined solvent casting and fused deposition modeling techniques. The tested composites were composed of polycaprolactone (PCL) matrix and tricalcium (TCP) micro-particles (binary composite) and additionally poly(D,L-lactide- co-glycolide), PLGA, (ternary composite). TCP and PLGA were used as a reinforcement of the composites. Tensile test was conducted in order to determine the effect of TCP and PLGA on mechanical properties of the composites. Introduction to TCP particles had slight effect of the Young's modulus. However, addition of TCP and PLGA to PCL matrix significantly improved the mechanical properties of the ternary composite.

15

Manufacturing and characterization of resorbable PLGA membranes for biomedical applications

Krok M., Ferreira C., Fernandes S., Kościelniak D., Dobrzyński P., Pamuła E.

Engineering of Biomaterials

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2011

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Vol. 14, no. 104

8--13

EN

Porous poly(L-lactide-co-glycolide) (PLGA) membranes were prepared by solvent-casting/porogen leaching method. Poly(ethylene-glycol) (PEG) with two molecular weights was used as a pore former. Mechanical properties of the membranes were analyzed in tensile test. Topography, pore size and surface roughness were characterized by atomic force microscopy on both sites of the membranes. PEG leached out percentage, thickness and wettability were also measured. Osteoblast-like cells were cultured on the membranes for 24 h and 6 days, and morphology, distribution and number of adhered cells as well as secretion of proteins and nitric oxide were measured. The results show that PEG molecular weight affected size and distribution of pores on both surfaces of the membranes. It resulted also in different mechanical characteristics of the membranes. In vitro experiments show that the membranes support adhesion and growth of osteoblast-like cells suggesting their usefulness for guided tissue regeneration (GTR).

16

Optimization of culture conditions of osteoblast-like cells on PLGA scaffolds

Wojak I., Hintze V., Hess R., Scharnweber D. S., Pamuła E.

Engineering of Biomaterials

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2010

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Vol. 13, no. 96-98

144--145