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The aim of this work was to develop new method for the production of chitosan/agarose (CHN/A) film that could serve as a potential artificial skin substitute for regenerative medicine applications. Within this new production method, the concentrations of biomaterial components (chitosan in CH3COOH and agarose in NaOH) were optimized to provide neutralization of the resultant mixture up to pH approx. 6.0 without uncontrolled precipitation (gelation) of chitosan constituent. Produced thin film was subjected to comprehensive evaluation of its biomedical potential by determination of mechanical, physicochemical, and biological properties. It was demonstrated that the developed CHN/A film reveals slightly acidic pH of 5.98 known to support skin regeneration, high exudate absorption capacity, and is prone to biodegradation in simulated enzymatic wound environment. Performed tensile test proved high elastic deformations of the film (Young's modulus = 0.02 MPa, elongation at break = 23%) in a wet state, which would allow suitable stretching after application at the wound site. Moreover, novel biomaterial is non-toxic and supports fibroblast growth on its surface. Based on the obtained results it may be concluded that the produced CHN/A film possesses all necessary features of the artificial skin substitute.

There is currently a growing demand for more effective thermal insulation materials with the best performance properties. This research paper presents the investigation results on the influence of two types of filler on the structure and properties of rigid polyurethane foam composites. Fly ash as a product of coal combustion in power plants and microspheres of 5, 10, 15, and 20 wt.%, were used as rigid polyurethane foams modifiers. The results of thermal analysis, mechanical properties testing, and cellular structure investigation performed for polyurethane composites show that the addition of fly ash, up to 10 wt.%, significantly improved the majority of the tested parameters. The use of up to 20 wt.% of microspheres improves the mechanical and thermal properties and thermal stability of rigid polyurethane foams.

The aim of this paper is the comparison of the thermal destruction course of one of the commercially available binders applied in the ALPHASET technology in dependence of the temperature, heating rate and the character of the atmosphere (inert, oxidising or reducing). The thermogravimetric analysis/differential scanning calorimetry/Fourier-transform infrared spectroscopy (TG/DSC/FTIR) system allowed for real-time analysis of the composition and intensity of gases emitted during slow heating in the inert and oxidising atmospheres. In addition, the TG/DTG/DSC investigation of the binder was performed in the reducing atmosphere. The pyrolysis gas chromatography coupled with mass spectrometry system allowed for the analysis of gases evolved at very fast heating in the inert atmosphere (pyrolysis) as a function of temperature. It has been proven that the type and amount of the gases emitted is highly dependent on the temperature, heating rate and the atmosphere in which it is performed. The highest versatility of harmful volatiles is produced during heating in the inert atmosphere. This type of atmosphere is present in the closest proximity of the liquid metal. Thus, to reduce the risk of exposure of the foundry workers, the extraction of the casting should be done under the hood, and sufficient personal protective equipment should be used.

Usage of CNTs as matrix modifiers during fabrication of CNFs from the electrospun polymer precursor is an interesting approach to obtain composite materials with a new set of properties. However, the progress in this field is hindered by the lack of consistency of the CNTs used in the studies and sometimes insufficient materials characterization. In this study, two types of CNTs were at first characterized to reveal their chemical composition and morphology (by TEM and XPS) and then used as matrix additives in the process of electrospinning. The outcome product was evaluated for morphology (SEM), chemical composition (XPS, FTIR), course of thermal transition (STA-FTIR) and level of structural arrangement (TEM combined with SAED) to answer the question how do CNTs interact with polymer matrix and how it impacts the process of thermal transition and properties of the as-received carbon nanofibers. Highly oxidized and short CNTs were found to increase the structural arrangement, catalyzing the thermal transition, while thin and long CNTs, with low amount of oxygen, entrap the nitrogen atoms, yielding nitrogen-doped CNFs that might be suggested as high-performance oxygen reduction reaction catalysts.

The aim of this work was to investigate how chemical functionalization affects the electronic properties of multi-walled carbon nanotubes, altering the electrophoretic deposition process: a method of choice for the fabrication of high quality, all-carbon nanotube (CNT) layers. Wet chemistry methods were applied to modify the surfaces of CNTs by insertion of various oxygen- and nitrogen-containing groups. Transmission electron microscopy revealed no significant changes in the material morphology, while X-ray photoelectron spectroscopy and Raman spectroscopy showed that changes in the chemical composition did not translate to the changes in the structure. Molecularly modelled optimized surface functional group geometries and electron density distributions allowed the calculation of the dipole moments (–COOH = 0.77; –OH = 1.65; –CON(CH3CH2)2 = 3.33; –CONH2 = 2.00; –NH2 = 0.78). Due to their polarity, the introduction of surface functional groups resulted in significant modifications of the electronic properties of CNTs, as elucidated by work function measurements via the Kelvin method and ultraviolet photoelectron spectroscopy. The work function changed from 4.6 eV (raw CNTs) to 4.94 eV for the –OH functionalized CNTs and 4.3 eV for the CNTs functionalized with –CON(CH3CH2), and was inversely proportional to the dipole moment values. Finally, using CNT dispersions, electrophoretic deposition was conducted, allowing the correlation of the work function of CNTs and the measured electrophoretic current with the impact on the deposits' qualities. Thus, a rational background for the development of carbon-based biomaterials was provided.

The impact of nanotechnology has triggered significant advances in a wide variety of fields, especially medicine. Within the biomedical field, the identification of key compounds involved in different pathologies and the diagnoses of those has become a pivotal activity that has been tremendously benefited from the use of nanobiosensors. These nanostructures, with the potential to identify a wide array of molecules through biological recognition processes, had provided a powerful tool for the rapid and sensitive quantification of pathogens, diseases, drug screening, genetic diseases, among other in vitro diagnostics applications. Therefore, the use of nanomaterials with different compositions, configurations, and morphologies had enabled a faster detection and higher reproducibility. In this chapter, novel examples of the use of different nanobiosensors are given, along with a detailed interpretation of their interactions with different biological targets, with the aim to elucidate the new trends of the field toward a better use of nanomaterials in medicine.

Cancer is one of the biggest healthcare concerns in our century, a disease whose treatment has become even more difficult following reports of drug-resistant tumors. When this happens, chemotherapy treatments fail or decrease in efficiency, leading to catastrophic consequences to the patient. This discovery, along with the fact that drug resistance limits the efficacy of current treatments, has led to a new wave of discovery for new methods of treatment. The use of nanomedicine has been widely studied in current years as a way to effectively fight drug resistance in cancer. Research in the area of cancer nanotechnology over the past decades has led to tremendous advancement in the synthesis of tailored nanoparticles with targeting ligands that can successfully attach to chemotherapy-resistant cancer by preferentially accumulating within the tumor region through means of active and passive targeting. Consequently, these approaches can reduce the off-target accumulation of their payload and lead to reduced cytotoxicity and better targeting. This review explores some categories of nanocarriers that have been used in the treatment of drug-resistant cancers, including polymeric, viral, lipid-based, metal-based, carbon-based, and magnetic nanocarriers, opening the door for an exciting field of discovery that holds tremendous promise in the treatment of these tumors.

Three-dimensional macroporous scaffolds are commonly used in bone tissue engineering applications since they provide sufficient space for cell migration and proliferation, facilitating bone ingrowth and implant vascularisation. The aim of this work was to combine two simple methods, freeze-drying and gas-foaming, in order to fabricate highly macroporous bone scaffolds made of chitosan/agarose matrix reinforced with nanohydroxyapatite. The secondary goal of this research was to comprehensively assess biomedical potential of developed biomaterials. In this work, it was demonstrated that simultaneous application of freeze-drying and gas-foaming technique allows to obtain hybrid (as proven by ATR-FTIR) macroporous bone scaffolds (pore diameter > 50¿µm) characterized by high open (70 %) and interconnected porosity. Novel scaffolds were non-toxic, favoured osteoblasts adhesion and growth and induced apatite formation on their surfaces, indicating their high bioactivity that is essential for good implant osseointegration. Biomaterials were also prone to enzymatic degradation, degradation in acidified microenvironment (e.g. osteoclast-mediated), and slow degradation under physiological pH of 7.4. Moreover, the scaffolds revealed microstructure (70 % open porosity, SSA approx. 30¿m2/g, high share of macropores with diameter in the range 100-410¿µm) and compressive strength (1–1.4¿MPa) comparable to cancellous bone, indicating that they are promising implants for cancellous bone regeneration.

Physicochemical, electrochemical and biological performance of 4 types of all-carbon nanotube layers was studied. Higher oxidation state of carbon was responsible for micro-scaled uniformity of the layers and excellent electrical conductivity, while nitrogen containing functional groups yielded materials with anisotropy similar to natural tissues and reduced work function. All materials were cytocompatible with mammalian fibroblasts (viability80%, cytotoxicity3% at day 7) and human dermal fibroblast (viability of cells70% at day 1), while reducing bacterial and cancer cells proliferation without adding any drug. After 8 h culture, a ~50% depletion in the number of Gram-positive bacteria was observed on materials with lower work function, while Gram-negative bacteria were more sensitive towards carbon coordination number and presence of nitrogen atoms (cell depletion of up to 48% on amidized carbon nanotubes). After 1-day culture,80% reduction in the melanoma cells number, connected with enhanced production of reactive oxygen species (ROS) was observed. All-carbon nanotube layers decreased bacteria and cancer cell functions without negatively influencing mammalian cells nor using drugs and we believe that this can be explained by various sensitivity of the tested cells towards exogenous ROS overproduction. As the concerns over implant-related infections as well as rates of antibiotic-resistant bacteria and chemotherapeutic-resistant cancer cells are growing, such materials should pave the way for a wide range of biomedical applications.

Osteochondral defects remain a huge problem in medicine today. Biomimetic bi- or multi-phasic scaffolds constitute a very promising alternative to osteochondral autografts and allografts. In this study, a new curdlan-based scaffold was designed for osteochondral tissue engineering applications. To achieve biomimetic properties, it was enriched with a protein component - whey protein isolate as well as a ceramic ingredient - hydroxyapatite granules. The scaffold was fabricated via a simple and cost-efficient method, which represents a significant advantage. Importantly, this technique allowed generation of a scaffold with two distinct, but integrated phases. Scanning electron microcopy and optical profilometry observations demonstrated that phases of biomaterial possessed different structural properties. The top layer of the biomaterial (mimicking the cartilage) was smoother than the bottom one (mimicking the subchondral bone), which is beneficial from a biological point of view because unlike bone, cartilage is a smooth tissue. Moreover, mechanical testing showed that the top layer of the biomaterial had mechanical properties close to those of natural cartilage. Although the mechanical properties of the bottom layer of scaffold were lower than those of the subchondral bone, it was still higher than in many analogous systems. Most importantly, cell culture experiments indicated that the biomaterial possessed high cytocompatibility towards adipose tissue-derived mesenchymal stem cells and bone marrow-derived mesenchymal stem cells in vitro. Both phases of the scaffold enhanced cell adhesion, proliferation, and chondrogenic differentiation of stem cells (revealing its chondroinductive properties in vitro) as well as osteogenic differentiation of these cells (revealing its osteoinductive properties in vitro). Given all features of the novel curdlan-based scaffold, it is worth noting that it may be considered as promising candidate for osteochondral tissue engineering applications.

Increased application of organic compounds, mainly in form of synthetic resins, used as binders for moulding and core sands in metal casting, may have an adverse effect on the environment and work conditions in foundry plants. In this article we focused on the identification of the degradation products formed during laboratory scale simulation of complex thermal degradation of commercial binder. For our investigation we have chosen the phenol-formaldehyde based resin hardened by a mixture of organic esters (PFRE) as it is widely used in the core and mould sand technology. The identified degradation products obtained during the experiments varied depending on mechanism used for pyrolysis. In the “slow” evaluation, simple compounds such as: CO, CO2, NH3, H2O, phenol and CH4 were generated. Meanwhile, during the “flash” pyrolysis (500, 700, 900 and 1100 °C), mainly phenol and its methyl and ethyl derivatives as well as benzene were released. It was determined that the pyrolysis products and their ratio depended on the temperature during the degradation process.

The aim of this study was to determine which procedure for β-1,3-glucan gelation - newly developed dialysis against calcium salt or described in the literature thermal technique - is more appropriate for fabrication of a biomaterial designed for bone tissue engineering applications. Thus, β-1,3-glucan/hydroxyapatite scaffolds were prepared based on two different methods and their physicochemical, microstructural, and biological properties were compared. Obtained results demonstrated that unlike thermal method-prepared β-1,3-glucan/hydroxyapatite material (glu/HAT), bone scaffold fabricated via dialysis method (glu/HA D) possessed rough surface resulting from the presence of CaCl2 precipitates as proven by SEM and EDS analysis. As a consequence, glu/HA D scaffold released Ca2+ ions to the surrounding environment positively affecting osteoblast behaviour and biomineralization in vitro. Since glu/HA D material exhibited better bioactivity and biocompatibility compared to the glu/HA T scaffold, it may be concluded that the dialysis method is more suitable for β-1,3-glucan/hydroxyapatite biomaterial fabrication.

Coating the material of choice with a layer of well-adhered carbon nanotubes is a subject of interest in many fields of materials science and industry. Electrophoretic deposition is one of the methods to handle this challenging task. In this process, careful designing of the deposition parameters is crucial in obtaining the product of strictly desired properties. This study was aimed to identify the influence of the diluent on the physicochemical ad electrochemical qualities of the final product. By analyzing the properties of the suspensions being used, we were able to hypothesize on the mechanisms of carbon nanotubes—liquid interactions and their outcome on the thickness, homogeneity, chemical and structural composition and electrical conductivity of the metal substrate covered with a layer of carbon nanotubes. We obtained a materials, composed of metal and a layer of CNTs, with conductivity that is superior to an unmodified metal. This types of materials may find numerous applications in fabrication of novel electronic devices, including the implantable electrodes for biomedicine—as reported in our previous studies, these types of coating are biocompatible.

Paulina Kazimierczak,1 Aleksandra Benko,2 Marek Nocun,2 Agata Przekora11Department of Biochemistry and Biotechnology, Medical University of Lublin, Lublin, Poland; 2Faculty of Materials Science and Ceramics, AGH University of Science and Technology, Krakow, PolandCorrespondence: Agata PrzekoraDepartment of Biochemistry and Biotechnology, Medical University of Lublin, Chodzki 1 Street, Lublin 20-093, PolandTel +48 81 448 7026Fax +48 81 448 7020Email agata.przekora@umlub.plBackground: Nanocomposites produced by reinforcement of polysaccharide matrix with nanoparticles are widely used in engineering of biomaterials. However, clinical applications of developed novel biomaterials are often limited due to their poor biocompatibility.Purpose: The aim of this work was to comprehensively assess biocompatibility of highly macroporous chitosan/agarose/nanohydroxyapatite bone scaffolds produced by a novel method combining freeze-drying with a foaming agent. Within these studies, blood plasma protein adsorption, osteoblast (MC3T3-E1 Subclone 4 and hFOB 1.19) adhesion and proliferation, and osteogenic differentiation of mesenchymal stem cells derived from bone marrow and adipose tissue were determined. The obtained results were also correlated with materials’ surface chemistry and wettability to explain the observed protein and cellular response.Results: Obtained results clearly showed that the developed nanocomposite scaffolds were characterized by high biocompatibility and osteoconductivity. Importantly, the scaffolds also revealed osteoinductive properties since they have the ability to induce osteogenic differentiation (Runx2 synthesis) in undifferentiated mesenchymal stem cells. The surface of biomaterials is extremely hydrophilic, prone to protein adsorption with the highest affinity toward fibronectin binding, which allows for good osteoblast adhesion, spreading, and proliferation.Conclusion: Produced by a novel method, macroporous nanocomposite biomaterials have great potential to be used in regenerative medicine for acceleration of the bone healing process.Keywords: XPS, wettability, protein adsorption, osteogenic differentiation, cell proliferation, cryogel

Effective management of chronic wounds with excessive exudate may be challenging for medical doctors. Over the years, there has been an increasing interest in the engineering of biomaterials, focusing on the development of polymer-based wound dressings to accelerate the healing of exuding wounds. The aim of this study was to use curdlan, which is known to support wound healing, as a base for the production of superabsorbent hybrid biomaterials (curdlan/agarose and curdlan/chitosan) with the intended use as wound dressings for highly exuding wound management. To evaluate the biomedical potential of the fabricated curdlan-based biomaterials, they were subjected to a comprehensive assessment of their microstructural, physicochemical, and biological properties. The obtained results showed that foam-like biomaterials with highly porous structure (66–77%) transform into soft gel after contact with the wound fluid, acting as typical hydrocolloid dressings. Novel biomaterials have the superabsorbent ability (1 g of the biomaterial absorbs approx. 15 ml of exudate) with horizontal wicking direction while keeping dry edges, and show water vapor transmission rate of approx. 1700–1800 g/m2/day which is recommended for optimal wound healing. Moreover, they are stable in the presence of collagenases, but prone to biodegradation in lysozyme solution (simulated infected wound environment). Importantly, the developed biomaterials are non-toxic and their surface hinders fibroblast attachment, which is essential during dressing changes to avoid damage to newly formed tissues in the wound bed. All mentioned features make the developed biomaterials promising candidates to be used as the wound dressings for the management of chronic wounds with moderate to high exudate.

Structural changes accompanying stabilization and carbonization processes of the two types of polyacrylonitrile (PAN) nanofiber precursors (pure PAN and PAN with carbon nanotubes) were studied using infrared spectroscopy (FTIR) and X-ray photoelectron spectroscopy (XPS). The fibrous membranes were preliminary stabilized in air followed by the two-step carbonization process under nitrogen atmosphere. IR absorption spectra showed that the introduction of a small amount of functionalized multiwall carbon nanotubes (MWCNT) into the PAN precursor has a significant impact on its stabilization process. Raman spectroscopy study showed that the structure of carbon nanofibers containing CNT is distinctly more ordered in comparison to pure carbon nanofibers. Based on the XPS analysis the concentration of heteroatoms and the type and amount of functional groups on the surfaces of both types of nanofibers were determined. The results indicate a high potential of functionalized MWCNT as a pyrolysis modifier of polymer precursor leading to the formation of carbon nanofibers with controlled structure and defined chemical state of the surface.

Common materials used as orthopedic implants are titanium and its alloys. To improve its compatibility with the environment of a living organism titanium implant surfaces are covered with bioactive layers of MWCNT. During the insertion into a living organism such material is exposed to direct contact with the patient's blood, which includes proteins – eg. albumin. The adsorption of albumin may constitute one of the early stages of implant surface modification serving cell adhesion. An analysis of this phenomenon in terms of the kinetics of deposition of protein on the surface of the implant confirms its biocompatibility in vivo . The proposed working model of the adsorption of albumin allows for choosing the best of time for the protein to form a stable connection with the surface of the titanium implant. Traditional methods of materials engineering and chemistry allow for the obtaining of information about the presence of a protein on the surface (UV–Vis, the wettability). The application of 2D correlation analysis, in turn, gains insight into the dynamics of the changes associated with the deposition of protein (the formation of a uniform layer, the change in conformation). This analysis has allowed for the selection of an optimal time of protein adsorption to the surface of the implant. Better compatibility with the body of the implant provides its modification by introducing layers that accelerate the material–tissue interactions. Such a composition is a layer of carbon nanotubes (MWCNTs) deposited on titanium by the electrophoretic (EPD) method. Using Raman spectroscopy and analyzing the spectra with the 2D correlation method it is possible to gain insight into the molecular structure of this layer. Our studies indicate that albumin in contact with the surface of titanium has obtained stable conformation after 30 min (confirmed by: UV–Vis, Raman). Shifts of the CH 2 , CH 3 stretching bands position as well as an analysis of the amide I band confirms this conformation. The dynamics of these changes are noticed as correlation peaks observed on 2D maps.

Multi-walled carbon nanotubes (MWCNTs) as a modifying phase on the titanium support can be potentially used for medical purposes as a material for the production of implants or implantable electrodes or for applications for cardiac surgery. Developing better blood compatible biomaterials must be connected with the condition of their anti-thrombogenic characteristic. A carbon nanotube layer was formed on a titanium plate coated in half with MWCNTs to have admission to: MWCNTs coating, to the Ti/MWCNTs interface region at the MWCNTs coating edge and finally to the Ti support. The Raman measurements were performed in two different locations: in the interface/edge region of the titanium and MWCNTs coating and in the center of the MWCNTs layer. For each of these positions, measurements in two different depths were performed: on the sample top surface of the MWCNT layer and near the bottom of the MWCNTs layer, i.e. at the titanium support interface. The studied sample regions differ in G-, D- and D′-mode structural characteristics as dispersion, crystallinity, the size of the arranged domains, and the distance between the point defects. The phase boundary region is more disordered and exposed to a greater surface tension. These features influence the interactions with albumin which represented the material behavior in contact with the tissue. The MWCNTs coating is hydrophilic (contact angle ∼55°), in the border area this value increases to ∼60°, then Ti support is hydrophobic (∼98°). Two dimensional correlation analysis allows us to unravel albumin-MWCNTs' interaction. The cross-peaks show a contribution from G + and G − carbon nanotubes bands and protein secondary structure demonstrating the formation of a film on the surface of the test sample and indicate the change of the albumin conformation during adhesion.

Fly ash (FA) is a waste material having great potential as modifier of mechanical and thermal properties in polyurethane (PUR) technology. There are very few reporting the use of fluidized bed combustion (FBC) FA in the production of PUR foams. In this work, authors have used the as received FBC FA as an additive to PUR rigid foams. The composite materials containing 5, 10, 15, and 20 wt% of FA were obtained by hand mixing and casting method. Microscopic observations of both unmodified and composite foams showed a well formed, cellular structure of the rigid foam. The cell structure was uniform; most of the cells were closed, which was an important parameter influencing thermal insulation properties of PUR materials. FA was uniformly distributed within PUR matrix and placed between cells. When the content of FA in composite foams increased, cells’ dimensions decreased, which suggested that FA particles acted as nucleation sites during the foam formation process. The absorption bands presented in IR spectrum of PUR foam confirmed the presence of urethane bonds in the unmodified foam material. The IR spectrum of as-received FA reconfirmed the crystalline phases recognized by XRD analysis, which were anhydrite, quartz, lime, calcite and aluminosilicate. No additional bands were observed which suggested that no chemical bonding between PUR matrix and FA particles occurred in the composite foam. The incorporation of FA into the PUR matrix, up to 10 wt%, improved the mechanical performance of the composite materials, when compared to unmodified PUR foam. Such a tendency suggested the occurrence of interfacial interactions between polymer matrix and FA particles, as well as the uniform distribution of the filler within PUR material. For all the materials analyzed, the addition of FA to PUR foam reduced both carbon content and the gross calorific value. The addition of FA improved the thermal stability of the PUR foam material (barrier effect of the FA prevented the release of gases from the foam structure).

The purpose of this study was to determine whether dialysis method allows for efficient protein entrapment in curdlan-based hydrogel. Thus, bovine serum albumin, a model of bioactive protein, was incorporated into curdlan matrix using ion-exchanging dialysis method against two concentrations of CaCl2 solution – 2% and 10%, respectively. Then, physicochemical, mechanical, and biological properties of the bovine serum albumin-loaded curdlan hydrogels were evaluated. Received results show that neither the polymer nor the entrapment procedure change the bovine serum albumin conformation (as proven by Fourier transform infrared spectroscopy and circular dichroism spectroscopy) and the process guarantees high protein entrapment efficiency (above 95%). The curdlan-based carrier obtained against 2% of CaCl2 solution was found to possess higher swelling ability, release greater amounts of bovine serum albumin (up to 4 weeks), and exhibit superior biocompatibility compared to curdlan-based carrier obtained against 10% of CaCl2 solution. Thus, dialysis method enables efficient protein entrapment in curdlan hydrogel and obtained protein carrier via dialysis method into 2% of CaCl2 solution may be considered as a promising protein delivery system especially for tissue engineering applications. It should be noted that we are the first who presented effective method for protein entrapment in curdlan hydrogel.

The aim of this study was to evaluate the impact of multi-walled carbon nanotubes (MWCNTs) after chemical surface functionalization on the interaction with a titanium surface. Two kinds of MWCNTs differing in terms of concentration of functional groups were deposited on the Ti surface using the electrophoretic deposition method (EPD). The study has shown the detailed analysis of the physicochemical properties of this form of carbon nanomaterial and received on their base coatings using various techniques, such as scanning electron microscopy (SEM), confocal microscopy, X-ray photoelectron spectroscopy (XPS) and Raman spectroscopy. The adhesion of the MWCNTs coatings to the Ti surface was determined using the shear test method, according to standard ASTM F-1044-05. These results indicated that one type of MWCNTs characterized by a higher concentration of functional groups has better adhesion to the metal surface than the second type. Analysis of the MWCNT–metal interface using Raman spectroscopy and SEM and STEM indicates the presence of phase built of MWCNT and TiO2. This phase could be a type of nanocomposite that affects the improvement of the adhesion of MWCNT to the Ti surface.

Coating the material with a layer of carbon nanotubes (CNTs) has been a subject of particular interest for the development of new biomaterials. Such coatings, made of properly selected CNTs, may constitute an implantable electronic device that facilitates tissue regeneration both by specific surface properties and an ability to electrically stimulate the cells. The goal of the presented study was to produce, evaluate physicochemical properties and test the applicability of highly conductible material designed as an implantable electronic device. Two types of CNTs with varying level of oxidation were chosen. The process of coating involved suspension of the material of choice in the diluent followed by the electrophoretic deposition to fabricate layers on the surface of a highly biocompatible metal—titanium. Presented study includes an assessment of the physicochemical properties of the material’s surface along with an electrochemical evaluation and in vitro biocompatibility, cytotoxicity and apoptosis studies in contact with the murine fibroblasts (L929) in attempt to answer the question how the chemical composition and CNTs distribution in the layer alters the electrical properties of the sample and whether any of these properties have influenced the overall biocompatibility and stimulated adhesion of fibroblasts. The results indicate that higher level of oxidation of CNTs yielded materials more conductive than the metal they are deposited on. In vitro study revealed that both materials were biocompatible and that the cells were not affected by the amount of the functional group and the morphology of the surface they adhered to.

The aim of the study was to fabricate titanium (Ti) material coated with functionalized carbon nanotubes (f-CNTs) that would have potential medical application in orthopaedics as an implantable electronic device. The novel biomedical material (Ti-CNTs-H2O) would possess specific set of properties, such as: electrical conductivity, non-toxicity, and ability to inhibit connective tissue cell growth and proliferation protecting the Ti-CNTs-H2O surface against covering by cells. The novel material was obtained via an electrophoretic deposition of CNTs-H2O on the Ti surface. Then, physicochemical, electrical, and biological properties were evaluated. Electrical property evaluation revealed that a Ti-CNTs-H2O material is highly conductive and X-ray photoelectron spectroscopy analysis demonstrated that there are mainly COOH groups on the Ti-CNTs-H2O surface that are found to inhibit cell growth. Biological properties were assessed using normal human foetal osteoblast cell line (hFOB 1.19). Conducted cytotoxicity tests and live/dead fluorescent staining demonstrated that Ti-CNTs-H2O does not exert toxic effect on hFOB cells. Moreover, fluorescence laser scanning microscope observation demonstrated that Ti-CNTs-H2O surface retards to a great extent cell proliferation. The study resulted in successful fabrication of highly conductive, non-toxic Ti-CNTs-H2O material that possesses ability to inhibit osteoblast proliferation and thus has a great potential as an orthopaedic implantable electronic device.

Recent researches suggest participation of minerals in the formation of life under primordial conditions. Among all of the minerals, quartz seems to be one of the most probable to take part in such processes. However, an external source of energy is needed, e.g. electric discharge. A device simulating the proposed conditions was designed and was used to simulate prebiotic conditions. Investigation of processes occurring during the stimulation of quartz with electric discharge was studied by means of Ultraviolet–visible (UV–VIS) spectroscopy, in order to monitor the generation kinetics of free radicals. Additionally, infrared spectroscopy was applied to identify chemical reaction products created in a solution of alanine or glycine, in the presence of quartz treated with electric discharge. Formation of increased amounts of free radicals, compared to experiments performed without quartz and/or amino acid, is reported, along with identification of possible degradation products of alanine. No synthetic reactions were observed. Electronic supplementary material The online version of this article (doi:10.1007/s11084-013-9328-3) contains supplementary material, which is available to authorized users.

Initial protein adsorption to the material surface is crucial for osteoblast adhesion, survival, and rapid proliferation resulting in intensive new bone formation. The aim of this study was to demonstrate that modification of a chitosan matrix of chitosan/hydroxyapatite (chit/HA) biomaterial for bone tissue engineering applications with linear β-1,3-glucan (curdlan) leads to promotion of serum protein adsorption to the resultant scaffold (chit/glu/HA) and thus in enhancement of osteoblast adhesion, spreading and proliferation. Fabricated biomaterials were pre-adsorbed with different protein solutions and then protein adsorption and osteoblast behavior on the scaffolds were compared. Moreover, surface chemical composition, wettability and surface energy of biomaterials were compared. Modification of the chitosan matrix with β-1,3-glucan introduces a greater polarpart in the resultant chitosan/β-1,3-glucan matrix presumably resulting from more OH groups within the curdlan structure. Moreover, FTIR-ATR results suggest that there might be some sort of chemical interaction between the NH group of chitosan and the OH group of β-1,3-glucan. As a consequence, the chit/glu/HA scaffold adsorbs significantly more adhesion proteins that are crucial for osteoblasts compared to the chit/HA material, providing a higher density culture of well-spread osteoblasts on its surface. Obtained results revealed that not only is chit/glu/HA biomaterial a promising scaffold for bone tissue engineering applications, but the specific polysaccharide chit/glu matrix itself is promising for use in the biomedical material field to modify various biomaterials in order to enhance osteoblast adhesion and proliferation on their surfaces.

The aim of the study was to fabricate and extensively characterize a layer of carbon nanotubes deposited on the surface of titanium, in order to prove that, by selecting proper type of carbon nanotubes and altering different parameters of the electrophoretic deposition process, we are able to obtain products having a different influence on cells—either favouring or inhibiting their survival. In the study, a novel mixture of solvents was used to suspend as-received tubes and then applied in the electrophoretic deposition. High charging capability and high yield of the obtained deposits are promising results when considering up-scaling the process. The surface of the obtained multi-walled carbon nanotubes-coated titanium samples was characterized using SEM, AFM, XPS and Raman microspectroscopy. The carbon nanotube layer showed nanorough topography and was formed of randomly and loosely distributed tubes, and XPS study revealed that there was a significant amount of C–O bonds. These properties were found to be favourable to osteoblast survival, spreading and growth.