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1
Content available 3D printed poly L-lactic acid (PLLA) scaffolds for nasal cartilage engineering
Jabłoński A., Kopeć J., Jatteau S., Ziąbka M., Rajzer I.
Engineering of Biomaterials
|
2018
|
Vol. 21, no. 144
15--19
EN
In this study the scaffolds for nasal cartilages replacement were designed using a software called Rhino 3D v5.0. The software parameters considered for the design of scaffolds were chosen and the scaffolds were fabricated using Fused Deposition Modeling (FDM), a rapid prototyping technology, using poly(L-lactic acid) (PLLA) filament. The topographical properties of the scaffolds were calculated through 3D model simulation. The morphology of obtained scaffold was observed by Scanning Electron Microscopy (SEM). The biological properties, i.e. bioactivity of the scaffolds, were assessed in Simulated Body Fluid. On the basis of natural cartilages images the external shape of the scaffold was designed using the 3D modeling software. The FDM is a useful method in fabrication of 3D bioactive implants for cartilage tissue engineering. Thanks to the use of 3D modeling software, it is possible to prepare and manufacture artificial cartilage in a controlled manner. Artificial scaffold made of PLLA polymeric matrix may mimic natural one by shape, topography, geometry, pore size, and their distribution. In addition, it is possible to guarantee appropriately selected biological properties such as biocompatibility and high bioactivity of scaffolds, which was proved using scanning electron microscopy (SEM) analysis. The surface observation of the 3D printed scaffolds showed in vitro formation of apatite after immersion in the SBF. What is more, it is possible to match the scaffold not only to the large cavity but also individually to each patient.
2
Content available Modeling, fabrication and characterization of 3D PLLA scaffolds plotted with commercial printer
Jablonski A., Kopec J., Jatteau S., Śliwka M., Ziąbka M., Rajzer I.
Engineering of Biomaterials
|
2017
|
Vol. 20, no. 143 spec. iss.
84
3
Content available A tubular polycaprolactone/hyaluronic acid scaffolds for nasal cartilage tissue engineering
Jatteau S., Kurowska A., Ziąbka M., Rajzer I.
Engineering of Biomaterials
|
2017
|
Vol. 20, no. 141
8--12
EN
In this preliminary study, 3D nanofibrous porous scaffolds in the form of spiral tubes for future application as nasal cartilages implants were fabricated by combining polycaprolactone electrospun fibers with drug modified hyaluronic acid gel. It is expected that the spiral form of the scaffold with open geometries, large surface area, and distance between the scaffold walls will be helpful for improving future cell penetration into the scaffolds, nutrient transport and metabolic waste removal, which are otherwise limited in conventional electrospun tissue-engineered scaffolds. The tubular scaffolds structure, its porosity and fibers’ diameter were assessed via scanning electron microscopy, and biological properties of the scaffolds were evaluated in an in vitro study using Simulated Body Fluid (SBF). SEM results showed that apatite formed within a short period on tubular scaffolds after its immersion in SBF, demonstrating high in vitro bioactivity of the scaffolds.
4
Content available Ocena trwałości włókien przeznaczonych na podłoża dla inżynierii tkankowej w płynach fizjologicznych
Rajzer I., Kwiatkowski R.
Engineering of Biomaterials
|
2014
|
Vol. 17, no. 128-129
11--15
PL
Bardzo dużą rolę w procesie degradacji implantów odgrywa środowisko płynów fizjologicznych, których wpływ zależy od właściwości fizycznych i chemicznych materiału polimerowego oraz od jego reaktywności. W niniejszej pracy oceniono wpływ płynu PBS na trwałość kompozytowych włókien polikaprolakton / hydroksyapatyt w warunkach in vitro. Stopień degradacji włókien określano na podstawie zmian pH medium, stężenia jonów sodu i potasu w płynie po inkubacji próbek oraz zmian masy próbek podczas inkubacji. Ocenę zmian zachodzących we włóknach pod wpływem płynu PBS przeprowadzono wykorzystując skaningową mikroskopię elektronową (SEM) oraz rentgenowską analizę strukturalną (WAXD). Badania degradacji włókien przeprowadzone podczas inkubacji próbek w płynach fizjologicznych wykazały, że wytworzone włókna kompozytowe charakteryzuję się stabilnością w środowisku płynów ustrojowych przez długi okres czasu. Niewielkie zmiany na powierzchni włókien, zaobserwowane po 10 miesiącach inkubacji, w płynie fizjologicznym, wskazują na rozpoczęcie procesu degradacji, stąd też można przypuszczać, że czas całkowitej biodegradacji włókien może być skorelowany z czasem potrzebnym do kompletnego odtworzenia tkanki.
EN
Very important role in the process of implant degradation is played by the physiological fluid environment, the impact of which depends on the physical and chemical properties of the polymers and on its reactivity. This study evaluates the effect of PBS on the stability of composite polycaprolactone/hydroxyapatite fibres in vitro. The degree of degradation of the fibres was determined by the changes in pH of the fluid, the concentration of sodium and potassium ions in the fluid after incubation of the sample, and the changes in the weights of samples during incubation. Assessment of the changes in the fibres under the influence of PBS was carried out using scanning electron microscopy (SEM) and X-ray structural analysis (WAXD). The study of the degradation of fibres carried out during the incubation of samples in physiological fluids showed that the composite fibres produced are stable in the environment of physiological fluids over a long period of time. Minor changes on the surface of the fibres, observed after 10 months of incubation, in a body fluid, indicate the start of a process of degradation, hence it can be assumed that the time of total biodegradation of the fibres may be correlated with the time needed for a complete restoration of tissue.
5
Content available Hyaluronic Acid-Coated Carbon Nonwoven Fabrics as Potential Material for Repair of Osteochondral Defects for medical applications
Rajzer I., Menaszek E., Bacakova L., Orzelski M., Błażewicz M.
Fibres & Textiles in Eastern Europe
|
2013
|
Vol. 21, no. 3 (99)
102--107
EN
Damaged articular cartilage is known to have poor capacity for regeneration. Carbon fibres (CFs) have been widely investigated as cellular growth supports in cartilage tissue engineering. However, the long duration of the process of cartilage restoration limits the applicability of CFs implants in the treatment of cartilage tissue defects. Hyaluronic acid (HA) plays a key role in cartilage tissue development, repair and function. In the present study we focused on the in vitro and in vivo evaluation of two types of carbon nonwoven fabrics: HA modified and non-modified carbon nonwovens. The results of in vitro studies showed that cells attached well and retained their good viability in the carbon nonwoven matrix. The incorporation of hyaluronic acid resulted in the enhancement of cell proliferation. The results of in vivo studies showed a faster process of tissue regeneration in the case of HA modified carbon nonwovens. The results presented indicated that HA-modified carbon materials seem to be a suitable material for the treatment of osteochondral defects.
PL
Uszkodzona chrząstka stawowa posiada słabą zdolność do regeneracji. Od lat prowadzone są badania nad zastosowaniem włókien węglowych w inżynierii tkankowej chrząstki, jako podłoży podtrzymujących wzrost komórek. Niestety długi proces odbudowy chrząstki w obrębie implantu węglowego ogranicza możliwość zastosowania włóknin węglowych w leczeniu ubytków chrzęstnych. Kwas hialuronowy (HA) jest składnikiem chrząstki odpowiedzialnym za jej właściwy rozwój oraz proces regeneracji. Modyfikacja włóknin kwasem hialuronowym może w korzystny sposób wpłynąć na własności biologiczne implantów węglowych. W pracy przedstawiono wyniki badań in vitro oraz in vivo nad włókninami węglowymi modyfikowanymi kwasem hialuronowym oraz nad włókninami niemodyfikowanymi. Z przeprowadzonych badań in vitro wynika, że modyfikacja włóknin węglowych kwasem hialuronowym powoduje wzrost proliferacji komórek hodowanych na tych materiałach. Natomiast wyniki badań in vivo wykazały, że proces regeneracji tkanki następuje szybciej w przypadku włóknin węglowych modyfikowanych kwasem hialuronowym niż w przypadku włóknin niemodyfikowanych. Przeprowadzone badania wskazują, że włóknina węglowa modyfikowana kwasem hialuronowym może być rozważana jako potencjalny materiał w leczeniu ubytków kostno-chrzęstnych.
6
Content available Needle-punched fibrous polycaprolactone scaffold for bone tissue engineering
Rajzer I., Grzybowska-Pietras J., Fabia J., Sarna E.
Engineering of Biomaterials
|
2013
|
Vol. 16, no. 121
2--5
EN
In the present work a three dimensional composite scaffolds for bone tissue engineering were created by a carding and needle-punch processes. Highly porous nonwoven fabrics were obtained from PCL and PCL/n-HAp cut fibers without the use of any chemicals during the manufacturing process. The properties of nonwoven scaffolds were examined by SEM, FTIR, DSC and TGA methods. The average pore diameter as well as the pore size distribution of nonwoven fabrics were measured by a capillary flow porometry. The obtained results suggest that needle-punching method can be used to produce highly porous microstructures with an interconnected pore network.
7
Content available Evaluation of PCL and PCL/n-HAp fibres processed by melt spinning
Rajzer I., Fabia J., Graczyk T., Piekarczyk W.
Engineering of Biomaterials
|
2013
|
Vol. 16, no. 118
2--4
EN
In this work the process for the manufacture of polycaprolactone fibres containing hydroxyapatite nanoparticles by melt spinning method was developed. The effect of nanohydroxyapatite content on the fibre structure and properties was investigated with FTIR, SEM, DSC, TGA methods. The mechanical properties of obtained fibres enable further processing to scaffolds by nonwoven technologies.
8
Content available Elektroprzędzenie i liofilizacja jako metody otrzymywania podłoży dla inżynierii tkankowej
Domalik-Pyzik P., Morawska-Chochół A., Wrona A., Chłopek J., Rajzer I.
Engineering of Biomaterials
|
2013
|
Vol. 16, no. 120
2--7
PL
Inżynieria tkankowa to interdyscyplinarną dziedziną, której celem jest opracowanie biologicznych substytutów pozwalających na zastąpienie i regenerację uszkodzonej tkanki. Bardzo ważnym jej elementem są podłoża, które stanowią rusztowanie umożliwiające wzrost i różnicowanie się odpowiednich komórek. Przedmiotem niniejszych badań było wytworzenie podłoży z polilaktydu i polikaprolaktonu. Materiały te formowano w dwóch procesach: na drodze elektro-przędzenia z roztworu polimeru oraz poprzez liofilizację, czyli suszenie sublimacyjne. Uzyskano w ten sposób podłoża o różnych właściwościach mechanicznych i mikrostrukturze. Wykazano zasadniczy wpływ metody i parametrów otrzymywania podłoży na ich końcowe właściwości. Wynikiem elektroprzędzenia są materiały włókniste o dużej odkształcalności, podczas gdy liofilizacja prowadzi do wytworzenia porowatych materiałów o wyższej wartości wytrzymałości mechanicznej i modułu Younga. Znaczący wpływ na parametry mechaniczne ma także forma podłoży nanowłóknistych. Podłoża w kształcie rurki cechują się wyższymi parametrami mechanicznymi niż w kształcie płaskich mat. Dodatkowo, wzrost wytrzymałości uzyskano poprzez owinięcie rurek włóknami alginianowymi. Połączenie metod elektroprzędzenia i liofilizacji prowadzi do wytworzenia asymetrycznych podłoży o wyższych parametrach mechanicznych. Metodą elektroprzędzenia otrzymano nanowłókniste materiały w formie mat i rurek, nadające się na podłoża do regeneracji naczyń krwionośnych. Liofilizacja pozwoliła natomiast na wytworzenie podłoży o różnej porowatości i morfologii. Dzięki połączeniu obu metod otrzymano asymetryczne podłoża PLAel/PCL40, które mogą znaleźć zastosowanie w sterowanej regeneracji tkanki kostnej.
EN
Tissue engineering is an interdisciplinary field which purpose is to produce biological substitutes able to replace and regenerate damaged tissue. Scaffolds are very important components because they allow growth and proliferation of appropriate cells. The purpose of this study was to manufacture different scaffolds using polylactide (PLA) and polycaprolactone (PCL). Materials were formed in two processes: electrospinning of a polymer solution and freeze-drying. Therefore it was possible to obtain scaffolds with various mechanical properties and microstructure. The influence of scaffold fabrication method and parameters on its final properties was demonstrated. Electrospinning outcomes were fibrous materials with high deformability, while freeze-drying led to fabrication of porous materials with higher mechanical strength and Young's modulus. The shape of nanofibrous scaffolds had also a significant influence on their mechanical properties. Scaffolds in the shape of a tube were characterized by higher mechanical properties than those in the shape of flat mats. Additional increase in mechanical strength has been achieved by wrapping the tubes with alginate fibers. Combination of electrospinning and freeze-drying contributed to formation of asymmetric scaffolds with better mechanical properties. Nanofibrous materials in the shape of mats and tubes, suitable for vascular engineering scaffolds were fabricated by electrospinning, while freeze-drying allowed for fabrication of scaffolds varying in porosity and morphology. Asymmetric PLAel/PCL40 scaffolds suitable for guided bone regeneration (GBR) were manufactured as a result of combining two above-mentioned methods.
9
Content available Elektroprzędzone membrany kompozytowe stymulują mineralizację w hodowlach komórek kostnych
Rajzer I., Menaszek E.
Engineering of Biomaterials
|
2012
|
Vol. 15, no. 113
35--39
PL
Biodegradowalne nanowłókniste membrany poddano badaniom in vitro, pozwalającym na ocenę stopnia różnicowania się i mineralizacji komórek kostnych w obecności potencjalnych podłoży tkankowych. Przedstawione badania oceniają wpływ mikrostruktury i składu chemicznego wytworzonych podłoży na przyczepność, proliferację i morfologię osteoblastów (NHOst). Badania procesu mineralizacji i aktywności ALP pozwoliły na ocenę procesu różnicowania się komórek.
EN
A biodegradable nanofibrous nonwoven membranes were analyzed in vitro as potential scaffolds for differentiation and mineralization of bone cells. In this study we investigate the effects of electrospun membranes microstructure and chemical composition on attachment, proliferation, and morphology of human NHOst osteoblasts. Mineralization process and ALP activity were studied to estimate the cells differentiation.
10
Content available remote Fabrication of Bioactive Carbon Nonwovens for Bone Tissue Regeneration
Rajzer I., Grzybowska-Pietras J., Janicki J.
Fibres & Textiles in Eastern Europe
|
2011
|
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.
11
Content available Properties of bilayer gelatin/polycaprolactone scaffolds
Rajzer I.
Engineering of Biomaterials
|
2011
|
Vol. 14, no. 104
2--4
EN
In this study, nanofibrous composite scaffolds have been fabricated in order to mimic the physical architecture of native extracellular matrix. Gelatin is a good candidate to mimic the chemical composition of natural collagen. It has many integrin-binding sites for cell adhesion and differentiation, which are found in collagen. However, electrospun scaffold made of gelatin had very poor mechanical properties. Therefore, in this study, bilayer nanofibrous scaffolds made of gelatin and poly(caprolactone) were produced by sequential electrospinning. The microscopic morphology, mechanical properties and porosity of electrospun bilayer gelatin/polycaprolactone scaffold were investigated.
12
Content available Mineralization and degradation of poly(ε -caprolactone) / hydroxyapatite electrospun membranes
Rajzer I., Kwiatkowski R., Sarna E., Janicki J.
Engineering of Biomaterials
|
2011
|
Vol. 14, no. 106-108
5--9
EN
The aim of this work was to study mineralization and degradation behavior of poly(ε-caprolactone) membranes modified with hydroxyapatite. The membranes have been obtained by electrospinning method. In vitro mineralization and degradation processes were carried out in simulated body fluid (SBF) as the release medium. The weight loss of the samples, water uptakes, pH and calcium, potassium, sodium ions concentrations of the solutions were determined. The chemistry and microstructure of the membranes after different times of incubation in SBF were characterized using SEM, FTIR, and XRD methods. The results of in vitro study in SBF indicate that incorporation of n-HAp strongly activates precipitation of the apatite like materials on the surface of nanofibers.
13
Content available Evaluation of PCL and PCL/HAp scaffolds processed by electrospinning and porogen leaching techniques
Rajzer I.
Engineering of Biomaterials
|
2011
|
Vol. 14, no. 103
4--7
EN
In order to improve the pore size of the polycapro-lactone (PCL) and polycaprolactone/hydroxyapatite (PCL/HAp) nanofibrous scaffolds, salt-leaching technique together with electrospinning method were applied. Salt particles were incorporated within the polymer nanofibrous matrix and then were leached out to generate some macropores. Microstructure, pore size distribution and average fibre diameter of the scaffold were investigated by scanning electron microscopy and PMI capillary flow porometer. Mechanical properties were determined by means of tensile test. Presence of hydroxyapatite and chemical characterization of the scaffold were done by FTIR analysis.
14
Content available Mechanical properties of carbon/hydroxyapatite nonwovens for bone tissue engineering
Rajzer I., Piekarczyk W., Grzybowska-Pietras J., Janicki J.
Engineering of Biomaterials
|
2010
|
Vol. 13, no. 93
6--9
15
Content available Electrospun biomimetic resorbable scaffold
Rajzer I., Piekarczyk W., Kwiatkowski R., Biniaś W., Janicki J.
Engineering of Biomaterials
|
2010
|
Vol. 13, no. 99-101
13--15
16
Content available Ca-deficient hydroxyapatite scaffolds from injectable calcium phosphate/chitosan cements
Rajzer I., Castano O., Engel E., Planell J. A.
Engineering of Biomaterials
|
2010
|
Vol. 13, no. 92
2--4
EN
Calcium phosphate cement (CPC) has been success-fully used in bone tissue regeneration for many years. However, poor mechanical properties and low biodegradation rate limit any further applications. R-cement has a higher solubility than conventional CPC and its reaction products (CDHA) are similar to the mineral phase of bone. In this work we have developed new CPC composition which consists of a mix of cement R, glycerol as a liquid phase carrier and a biodegradable hydrogel (chitosan) which acts as a binder and was incorporated into R-cement to strengthen this biomaterial. The cement past was found to be stable in a syringe (even after two month of storage in the freezer) and hardened only after being exposed to biological fluids.
17
Content available Biomimetic fibrous composite membranes for bone tissue engineering
Rajzer I., Chrzanowski W., Biniaś W., Sarna E., Janicki J.
Engineering of Biomaterials
|
2010
|
Vol. 13, no. 93
2--5
EN
One of the major challenges in biomaterials and tissue engineering is to guide the cell differentiation to the specific phenotype, therefore allow the formation of the tissue of certain type. This can be achieved by manipulating the structural, geometrical and chemical characteristics of the tissue engineering constructs. In our studies we concentrated on the chemical modifications of the polymer based materials for tissue engineering. The primary aim of our study was to incorporate nano size hydroxyapatite (n-HAp) crystals into the polymer fibres and form membranes, which are a core to the construction of novel scaffolds for tissue regeneration. We hypothesised that n-HAp will significantly improve the bioactivity of the polymer based membranes due to the presence of chemical cues. We developed a simple method to fabricate PLDL/n- HAp composite membranes using electrospinning process. The investigation showed that the incorporation of the n-HAp particles in the polymer spinning solution induced changes in the material surface morphology. FTIR analysis confirmed the presence of apatite on the surface of the membrane' fibers. The bioactivity analysis, which was based on SEM observation of the membranes surface, showed that after only 7 days immersion in SBF, the PLDL/n-HAp -membranes were completely covered by the apatite layer. This was not observed for pure PLDL membranes.
18
Content available remote Repair of knee cartilage defects with modified carbon fibre implants – preliminary study
Menaszek E., Orzelski M., Silmanowicz P., Rajzer I., Błażewicz M.
Engineering of Biomaterials
|
2009
|
Vol. 12, no. 88
11--15
EN
The paper presents promising results of our pilot study. The objective of this study was to investigate the effect of modified carbon fibres on cartilage regeneration. Fullthick knee articular cartilage defects in rabbits were filled with equal portions of pure carbon fibres of carbon fibres enriched with hydroxyapatite, hyaluronan or calcium alginate. Historical specimens containing implanted carbon fibres after 4, 8, 16 and 24 weeks from the surgery were prepared. Carbon fibres modified with hydroxyapatite generated bone growth, while those without modification and modified with hyaluronan supported cartilage regeneration.
19
Content available Opracowanie technologii wytwarzania modyfikowanych hydroksyapatytem włóknin węglowych przeznaczonych na podłoża dla inżynierii tkankowej
Rajzer I., Grzybowska-Pietras J., Morcinek S., Janicki J.
Engineering of Biomaterials
|
2009
|
Vol. 12, no. 89-91
144--146
20
Content available Kompozytowe włókna polilaktyd/hydroksyapatyt otrzymywane metodą przędzenia ze stopu
Rajzer I., Rom M., Fabia J., Morcinek S., Zima A., Ślósarczyk A., Janicki J.
Engineering of Biomaterials
|
2009
|
Vol. 12, no. 89-91
149--150
PL
W pracy zaproponowano metodę produkcji nano-kompozytowych włókien na bazie polilaktydu (PLA) i nano-hydroksyapatytu (n-HAp).
EN
In the present work, the method of production of nanocomposite fibers based on polylactide acid (PLA) and nano-hydroxyapatite (n-HAp) is proposed.
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