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Streszczenie:
An innovative approach to treating bone defects is using synthetic bone substitutes made of biomaterials. The proposed method to obtain polylactide scaffolds using the phase inversion technique with a freeze extraction variant enables the production of substitutes with morphology similar to cancellous bone (pore size 100–400 µm, open porosity 94%). The high absorbability of the implants will enable their use as platelet-rich plasma (PRP) carriers in future medical devices. Surface modification by dipping enabled the deposition of the hydrophilic chitosan (CS) layer, maintaining good bone tissue properties and high absorbability (850% dry weight). Introducing CS increases surface roughness and causes local changes in surface free energy, promoting bone cell adhesion. Through this research, we have developed a new and original method of low-temperature modification of PLA substitutes with chitosan. This method uses non-toxic reagents that do not cause changes in the structure of the PLA matrix. The obtained bone substitutes are characterised by exceptionally high hydrophilicity and morphology similar to spongy bone. In vitro studies were performed to analyse the effect of morphology and chitosan on cellular viability. Substitutes with properties similar to those of cancellous bone and which promote bone cell growth were obtained.

Słowa kluczowe:
chitosan, polylactide, bone substitute, tissue regeneration

Streszczenie:
In 2002, Robert Langer proposed that new polyester for tissue engineering should have good mechanical properties followed by: covalent bonding (as crosslinking) and hydrogen-bonding interactions; and should be elastic like rubber materials due to three-dimensional network structure. Considering these hypotheses, a polyester made of glycerol and citric acid was designed in this work. Poly(glycerol citrate) should be attractive for tissue engineering because both glycerol and citric acid, taking part in natural human metabolic pathways; and due to the reactant's functionality, 3D networks should be produced easily. Moreover, the reagents are cheap, available, and often used in the food and pharmaceutical industries. In this work, poly(glycerol citrate) was synthesized and then used with PLA for creating porous nonwovens by electrospinning. Produced materials were tested for possible application in the field of tissue engineering. The obtained materials have properties similar to collagen fibers, but still, require refinement for medical applications.

Słowa kluczowe:
electrospinning, poly(glycerol citrate), polylactide, tissue engineering

Streszczenie:
A nonplanar polylactide scaffold to be used in tissue engineering was obtained by freeze‐extraction method. Properties of the scaffold were modified by adding Eudragit® E100. The impact of the modification on morphology, porosity and pore size, mass absorbability, mechanical properties was determined. Scanning electron microscopy (SEM), hydrostatic weighing test, static compression test was used to this end. The chemical composition of the scaffold was defined based on infrared spectroscopy (FTIR) and energy‐dispersive X‐ray spectroscopy (EDX). Biocompatibility was confirmed by quantitative tests and microscopic observation. The obtained results show that the obtained scaffolds may be applied as a carrier of hydrophilic cellular growth factors for more efficient tissue regeneration.

Słowa kluczowe:
cellular studies, Eudragit® E100, freeze-extraction, poly-L-lactide

Streszczenie:
Implants in the form of polymer scaffolds are commonly used to regenerate bone tissue after traumas or tooth extractions. However, few implant formation methods enable building polymer scaffolds allowing to reconstruct larger bone losses without immune response. Spacious, porous poly-l-lactide implants with considerable volume were obtained using the phase inversion method with the freeze-extraction variant. The calcium phosphate (CaP) coating was deposited on implant surfaces with the biomimetic method to improve the implant's osteoconductivity. The substitues morphology was characterized-porosity, size and shape of pores; mechanical properties, mass absorbability of implants before and after mineralization. The characteristics were provided with scanning electron microscopy (SEM), static compression test and hydrostatic weighing, respectively. The presence of CaPs in the entire volume of the implant was confirmed with SEM and infrared spectroscopy with Fourier transform (FTIR). The biocompatibility of scaffolds was confirmed with in vitro quantitative test and microscopic observations. The obtained results show that the implants can be used in tissue engineering as a vehicle of platelet-rich plasma to regenerate critical spongy bone losses.

Słowa kluczowe:
bone graft, calcium phosphate(s), cell culture

Streszczenie:
This study was conducted as a first step in obtaining eco-friendly fibres for medical applications using a synthesised oligomer poly(glycerol succinate) (PGSu) as an additive for synthetic poly(L-lactic acid) (PLLA) and poly (L-lactide-co-caprolactone) (PLCL). The effects of the oligomer on the structure formation, morphology, crystallisation behaviour, and mechanical properties of electrospun bicomponent fibres were investigated. Nonwovens were investigated by means of scanning electron microscopy (SEM), wide angle X-ray scattering (WAXS), differential scanning calorimetry (DSC), and mechanical testing. The molecular structure of PLLA fibres is influenced by the presence of PGSu mainly acting as an enhancer of molecular orientation. In the case of semicrystalline PLCL, chain mobility was enhanced by the presence of PGSu molecules, and the crystallinity of bicomponent fibres increased in relation to that of pure PLCL. The mechanical properties of bicomponent fibres were influenced by the level of PGSu present and the extent of crystal formation of the main component. An in vitro study conducted using L929 cells confirmed the biocompatible character of all bicomponent fibres.

Słowa kluczowe:
poly(glycerol succinate), plasticiser, eco-friendly polymer, electrospinning, hyperbranched polyester

Streszczenie:
The main goal of tissue engineering (TE) is supporting the regeneration of damaged tissues that are difficult to regenerate. The experimental results of the preparation of semi-permeable membranes for cell cultures are presented. The effect of the PLA molecular weight and addition of pore precursors on the morphology of the membranes was studied. The pore precursor of choice was polyvinylpyrrolidone (PVP). It was found that semi-permeable membranes for application in tissue engineering can be prepared with polylactides of molecular weight more significant than 37,000 g/mol. Moreover, it was observed that the growth of the molecular weight of the polymer, the porosity, the size of the pores, the Young modulus and maximum tensile increased. Additionally, to obtain a better morphology of the membranes, PVP should be added to the polymeric solution. Positive growth of L929 fibroblast cells on the obtained scaffolds was shown.

Słowa kluczowe:
biodegradable polymers, cell cultures, L929 fibroblasts, polylactide, scaffolds, tissue engineering

Streszczenie:
Polyester 3D scaffolds were obtained by dry inversion phase method. The influence of a polymer and liquid pore precursor type on the 3D scaffolds morphology, porosity and mechanical properties was tested. Polymers and precursors forming a porous structure were identified. It was found that 3D scaffolds having the most preferable structure for cell cultures were obtained from polylactide with the addition of n‐butanol as the liquid pore precursor.

Słowa kluczowe:
liquid pore precursors, mechanical properties, dry inversion phase method, 3D scaffolds

Streszczenie:
Two types of poly(glycerol sebacate) (PGS) prepolymers were synthesized and electrospun with poly(l-lactic acid) (PLA), resulting in bicomponent nonwovens. The obtained materials were pre-heated in a vacuum, at different times, to crosslink PGS and investigate morphological and structural dependencies in that polymeric, electrospun system. As both PGS and PLA are sensitive to pre-heating (crosslinking) conditions, research concerns both components. More interest is focused on the properties of PGS, considering further research for mechanical properties and subsequent experiments with PGS synthesis. Electrospinning of PGS blended with PLA does not bring difficulties, but obtaining elastomeric properties of nonwovens is problematic. Even though PGS has many potential advantages over other polyesters when soft tissue engineering is considered, its full utilization via the electrospinning process is much harder in practice. Further investigations are ongoing, especially with the promising PGS prepolymer with a higher esterification degree and its variations.

Słowa kluczowe:
electrospinning, degradable polymers, synthesis, structure, crosslinking

Streszczenie:
Zbadano wpływ dodatku ciekłych prekursorów porów na morfologię, porowatość i właściwości mechaniczne polilaktydowych rusztowań komórkowych. Rusztowania otrzymano metodą mokrej inwersji faz w wariancie freeze extraction. Oceniono cytotoksyczność wybranych rusztowań w stosunku do fibroblastów mysich oraz ich przydatność do hodowli komórkowych. Wykazano, że dodatek prekursora porów dopolilaktydu korzystnie zmienia morfologię wytworzonych rusztowań, jednocześnie pogarszając ich wytrzymałość mechaniczną. Stwierdzono, że polilaktydowe rusztowania komórkowe z powodzeniem mogą być wykorzystywane do hodowli komórkowych.

Słowa kluczowe:
usztowania komórkowe, polilaktyd, hodowle komórkowe, fibroblasty

Streszczenie:
Results of the preparation of semi-permeable membranes made of biodegradable polymers membranes were presented. Among known polyesters, polylactide was selected for research. The membranes were obtained using wet phase inversion method. The influence of polyvinylpyrrolidone and polymeric nano-non-wovens as pores precursors on the structure of obtained membranes was analysed. It was shown, that utilisation of polymeric nano-non-wovens enabled preparation of semi-permeable membranes, which could be used as wide-pore 3D-type cellular scaffolds.

Słowa kluczowe:
Biodegradable polymers membranes, Biodegradable polyesters, Porous three-dimensional scaffolds, Inversion phase method