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Appropriate protection and guiding are crucial during peripheral nerves repair. New generation nerve guidance conduits (NGCs) should not only provide mechanical support for the damaged nerve but also support healing processes. One of the most promising tissue regeneration applications is fibrous biomaterials since they are characterized by high porosity, flexibility, and strength. Additionally, they enable cell adhesion and proliferation. In this study, novel fibrous nanocomposites were obtained by applying the electrospinning technique, using polylactic acid (PLA) as a polymeric matrix which was further modified with metallic nanoparticles coated with conductive polymers. Such an approach resulted in the obtainment of biomaterials with a potential ability to conduct nerve impulses. The chemical structure of the obtained composites, as well as the morphology of ready products and separate nanocomponents, were investigated using Fourier-transform infrared spectroscopy (FTIR), transmission electron microscope (TEM) and scanning electron microscope (SEM) techniques. Furthermore, conductive and swelling properties in various media were determined. Finally, biomaterials were confirmed to be non-cytotoxic to L929 mouse fibroblasts and 1321N1 human glial cells. Based on the presented results, it can be concluded that nanofibrous nerve guidance conduits have all the key properties in the process of peripheral nerve regeneration and may constitute an important step in novel NGCs development. [ABSTRACT FROM AUTHOR]

Tissue engineering constitutes the most promising method of severe peripheral nerve injuries treatment and is considered as an alternative to autografts. To provide appropriate conditions during recovery special biomaterials called nerve guide conduits are required. An ideal candidate for this purpose should not only be biocompatible and protect newly forming tissue but also promote the recovery process. In this article a novel, multilayered biomaterial based on polyvinylpyrrolidone, collagen and chitosan of gradient structure modified with conductive nanoparticles is presented. Products were obtained by the combination of electrospinning and electrospraying techniques. Nerve guide conduits were subjected to FT-IR analysis, morphology and elemental composition study using SEM/EDS as well as biodegradation. Furthermore, their effect on 1321N1 human cell line was investigated by long-term cell culture. Lack of cytotoxicity was confirmed by XTT assay and morphology study. Obtained results confirmed a high potential of newly developed biomaterials in the field of nerve tissue regeneration with a special focus on injured nerves recovery. [ABSTRACT FROM AUTHOR]

Skin is the first barrier against pathogens and harmful external factors. Each damage of this tissue may cause microbial infection and danger to internal organs. Burns which may be a result of the exposure to radiation, chemicals or high temperature leads to the significant disruption of skin functions. The most promising method for this tissue recovery is regenerative medicine which requires application of three-dimensional biocompatible scaffolds. The biomaterials enable skin cells proliferation and new tissue formation under in vitro conditions. They can be prepared from synthetic and natural polymers and their combination. The application of additional components such as nanoparticles may enhance their mechanical properties and have a positive impact on fibroblasts divisions and extra cellular formation. One of the most promising raw materials for scaffolds is chitosan -a chitin derivative. It may be obtained from waste biomass such as crabs, shrimps and lobsters exoskeletons. Chitosan is non-toxic, biodegradable and have antibacterial properties. The aim of the following study was to obtain novel chitosan derivatives doped with the gold nanoparticles using only natural components such as orange peels and fatty acid derivative. Proposed modification strategy resulted in the preparation of the novel, biodegradable and biocompatible material with interesting properties. The products were analysed by UV-Vis and FT-IR methods. The scaffolds were investigated over their susceptibility to enzymatic degradation. Finally, the biomaterials were verified over their cyto-compability with human dermal fibroblasts. The results showed that the proposed synthesis pathway resulted in the obtained of the chitosan biomaterials with high potential in medicine. [ABSTRACT FROM AUTHOR]

Tissue engineering is a branch of science that focuses on methods and techniques for the creation of new tissues and organs for the therapeutic reconstruction of the damaged organ by providing support structures, cells, molecular and mechanical signals for regeneration to the desired region. Conventional implants made of inert materials can eliminate only physical and mechanical defects of damaged tissues. The goal of tissue engineering is to restore biological functions, that is regeneration of tissues, and not only to replace it with a substitute made of synthetic material. The most important challenges of tissue engineering include the development of new biomaterials that will be used as three-dimensional scaffolds for cell cultures. Such scaffolding must be characterized by biocompatibility and biodegradability. The aim of the research was to obtain biomaterials based on acylated chitosan. The result of the work was to obtain three-dimensional scaffolding with bioactive properties based on raw materials of natural origin. The biomaterials were modified with ferrimagnetic nanoparticles which are capable of electromagnetic stimulation of proliferation. [ABSTRACT FROM AUTHOR]

Carbon Quantum Dots (CQDs) are objects with a size less than 10 nm that have the ability to emit radiation in the visible range from blue to red depending on the excitation radiation used. Quantum dots are used in in vitro bioimaging of cell structures or creation of biosensors. In contrast to classic nanodots, which are obtained from simple sulphides, selenides or metal tellurides, carbon quantum dots are constructed from a non-toxic, biocompatible carbon core, thanks to which it is possible to apply quantum carbon dots in bio-imaging in-vitro or in-vivo biological structures with minimal cytotoxic effect on cells. The aim of the research was to obtain carbon nanodots capable of emitting fluorescence using lignin from waste biomass. The CQDs were functionalized with amino-acids. The result of the work was to obtain a series of CQDs with advanced luminescence properties using hydrothermal and microwave assisted methods. Ready products were investigated over their cytotoxicity. [ABSTRACT FROM AUTHOR]

Tissue engineering provides alternative solutions to traditional transplantation. In this study a novel strategy of chitosan scaffolds obtainment based on selective O-crosslinking using Aspartic acid and the addition of TiO2 nanoparticles is presented. Prepared under microwave conditions biomaterials were of increased mechanical and thermal durability thanks to NPs presence comparing to pure chitosan. Moreover porous scaffolds maintained antimicrobial activity against S. Aureus and E. Coli. Biomaterials were susceptible to in vitro biodegradation and degradation. Hydrogels exhibited positive impact on proliferation activity of fibroblasts. Thus they may be applied as 3D scaffolds in tissue engineering focused on wound healing. [ABSTRACT FROM AUTHOR]

In this work we present a novel strategy for chitosan-based scaffolds. Chitosan is a versatile biopolymer obtained from waste biomass known of its favorable biological properties. Thus it can replace other polymers in the preparation of bioactive scaffolds. To increase its durability chitosan can be crosslinked into form of the hydrogel yet application of toxic crosslinkers may lead to loss of biocompability. Mesenchymal stem cells can be used in cell therapy for advanced wound treatment. However their culture requires special biomaterials application. In this article a novel microwave-assisted synthesis method for bioactive chitosan scaffolds is presented. [ABSTRACT FROM AUTHOR]

Carbon nanomaterials in the form of quantum dots have a high potential due to their luminescent properties and low cytotoxicity which allows their use in optical probes for use in bioimaging and biodetection. In this article, we present a novel type of nanomaterials and their obtainment method under microwave-assisted conditions using poly(L-lysine) as a raw material. The ready products were characterized over their chemical structure, pH-dependent fluorescence properties and cytotoxicity on human dermal fibroblasts. Moreover, their antioxidant activity as well as ability to biologically active molecules (vitamins) and heavy metal ions detection was evaluated. The results confirmed the obtainment of biocompatible nanomaterials with advanced properties and good water solubility according to sustained development principles. [ABSTRACT FROM AUTHOR]

Bone tissue is the second tissue to be replaced. Annually, over four million surgical treatments are performed. Tissue engineering constitutes an alternative to autologous grafts. Its application requires three-dimensional scaffolds, which mimic human body environment. Bone tissue has a highly organized structure and contains mostly inorganic components. The scaffolds of the latest generation should not only be biocompatible but also promote osteoconduction. Poly (lactic acid) nanofibers are commonly used for this purpose; however, they lack bioactivity and do not provide good cell adhesion. Chitosan is a commonly used biopolymer which positively affects osteoblasts' behavior. The aim of this article was to prepare novel hybrid 3D scaffolds containing nanohydroxyapatite capable of cell-response stimulation. The matrixes were successfully obtained by PLA electrospinning and microwave-assisted chitosan crosslinking, followed by doping with three types of metallic nanoparticles (Au, Pt, and TiO 2 ). The products and semi-components were characterized over their physicochemical properties, such as chemical structure, crystallinity, and swelling degree. Nanoparticles' and ready biomaterials' morphologies were investigated by SEM and TEM methods. Finally, the scaffolds were studied over bioactivity on MG-63 and effect on current-stimulated biomineralization. Obtained results confirmed preparation of tunable biomimicking matrixes which may be used as a promising tool for bone-tissue engineering.

Burns affect almost half a million of Americans annually. In the case of full-thickness skin injuries, treatment requires a transplant. The development of bioactive materials that promote damaged tissue regeneration constitutes a great alternative to autografts. For this reason, special attention is focused on three-dimensional scaffolds that are non-toxic to skin cells and can mimic the extracellular matrix, which is mainly composed of nanofibrous proteins. Electrospinning, which enables the preparation of nanofibers, is a powerful tool in the field of biomaterials. In this work, novel hybrid poly (lactic acid)/chitosan biomaterials functionalized with three types of nanoparticles (NPs) were successfully developed. ZnO, Fe 3 O 4 , and Au NPs were investigated over their morphology by TEM method. The top layer was obtained from PLA nanofibers, while the bottom layer was prepared from acylated chitosan. The layers were studied over their morphology by the SEM method and their chemical structure by FT-IR. To verify their potential in burn wound treatment, the scaffolds' susceptibility to biodegradation as well as moisture permeability were calculated. Also, biomaterials conductivity was determined in terms of electrostimulation. Finally, cytotoxicity tests were carried out by XTT assay and morphology analysis using both fibroblasts cell line and primary cells. The hybrid nanofibrous scaffolds displayed a great potential in tissue engineering.