Mechanical characterization supposes a key step in the development of cultured meat to help mimicking the sensorial properties of already existing commercial products based on traditional meat. This work presents two well stablished methods that can help studying cultured meat mechanical characteristics: texture profile analysis (double compression test) and rheology. These techniques provide data about the elastic and viscous behaviour of the samples but also values about other texture characteristics such as springiness, cohesiveness, chewiness and resilience. In this work, we present a comparison of cultured meat-based samples with commercial of the shelf common meat products (sausage, turkey and chicken breast). Results show that both Young's and Shear modulus in the cultured meat samples can be compared to commercial products in order to understand its properties. The texture characteristics for the cultured meat studied, show values within the range of commercial products. These results demonstrate the applicability of this methodology for the adjustment of mechanical properties of cultured meat products.

An appealing strategy that overcomes the hydrophobicity of pristine graphene and favors its interaction with biological media is colloidal stabilization in aqueous medium with the support of a biomolecule, such as flavin mononucleotide (FMN), as exfoliating/dispersing agent. However, to establish FMN-stabilized graphene (PG-FMN) as suitable for use in biomedicine, its biocompatibility must be proved by a complete assessment of cytotoxicity at the cellular level. Furthermore, if PG-FMN is to be proposed as a theranostic agent, such a study should include both healthy and tumoral cells and its outcome should reveal the nanomaterial as selectively toxic to the latter. Here, we provide an in-depth comparative in vitro analysis of the response of Saos-2 human sarcoma osteoblasts (model tumor cells) and MC3T3-E1 murine preosteoblasts (undifferentiated healthy cells) upon incubation with different concentrations (10-50 μg mL-1) of PG-FMN dispersions constituted by flakes with different average lateral size (90 and 270 nm). Specifically, the impact of PG-FMN on the viability and cell proliferation, reactive oxygen species (ROS) production, and the cellular incorporation process, cell-cycle progression, and apoptosis has been evaluated. PG-FMN was found to be toxic to both types of cells by increasing ROS production and triggering cell-cycle arrest. The present results constitute a cautionary tale on the need to establish the effect of a nanomaterial not only on tumor cells but also on healthy ones before proposing it as anticancer agent.

Two-dimensional transition metal dichalcogenides (TMDCs), such as MoS2 and WS2, have recently emerged as nanomaterials with potential use in biomedicine. An attractive means to favor their interaction with biological media is the use of proper biomolecules as exfoliating/dispersing agents. Here, MoS2 flakes were stabilized with different small functional biomolecules such as adenosine monophosphate (AMP), guanosine monophosphate (GMP) and flavin mononucleotide (FMN) through the strong nucleotide−MoS2 interaction of Lewis acid-base type, rather than just on the weak dispersive and hydrophobic forces commonly associated with the use of many surfactants. The impact of the nucleotide-stabilized MoS2 flakes on the viability and cell proliferation, on the production of intracellular reactive oxygen species (ROS), and on the preosteoblast differentiation process (early stage) has been also evaluated, as well as the incorporation and intracellular localization of the nanomaterials by MC3T3-E1 and Saos-2 cells. The nucleotide-stabilized MoS2 flakes were found to exhibit excellent biocompatibility. Furthermore, their incorporation did not affect the integrity of the cell plasma membrane, which makes them ideal candidates for delivering drug/gene directly into cells. The in vitro cell response of tumor cells to these nanomaterials differs from that of undifferentiated cells, which provides the basis for their potential use in cancer therapy.

Macroscopic fibers of carbon nanotubes (CNT) have emerged as an ideal architecture to exploit the exceptional properties of CNT building blocks in applications ranging from energy storage to reinforcement in structural composites. Controlled synthesis and scalability are amongst the most pressing challenges to further materialize the potential of CNT fibers. This work shows that under floating catalyst chemical vapor conditions in the direct spinning method, used both in research and industry, the ceramic reactor tube plays an unsuspected active role in CNT growth, leading for example to doubling of reaction yield when mullite (Al 4+2x Si 2−2x O 10−x (x ≈ 0:4)) is used instead of alumina (Al 2 O 3 ), but without affecting CNT morphology in terms of number of layers, purity or degree of graphitization. This behaviour is confirmed for different carbon sources and when growing either predominantly single-walled or multi-walled CNTs by adjusting promotor concentration. Analysis of large Si-based impurities occasionally found in CNT fiber fabric samples, attributed to reactor tube fragments that end up trapped in the porous fibers, indicate that the role of the reactor tube is in catalyzing the thermal decomposition of hydrocarbons, which subsequently react with floating Fe catalyst nanoparticles and produce extrusion of the CNTs and formation of an aerogel. Reactor gas analysis confirms that extensive thermal decomposition of the carbon source occurs in the absence of Fe catalyst particles, and that the concentration of different carbon species (e.g. carbon dioxide and ethylene) is sensitive to the reactor tube type. These finding open new avenues for controlled synthesis of CNT fibers by decoupling precursor decomposition from CNT extrusion at the catalyst particle.

The preparation of graphene-based nanomaterials (GBNs) with appropriate stability and biocompatibility is crucial for their use in biomedical applications. In this work, three GBNs differing in size and/or functionalization have been synthetized and characterized, and their in vitro biological effects were compared. Pegylated graphene oxide (GO-PEG, 200-500 nm) and flavin mononucleotide-stabilized pristine graphene with two different sizes (PG-FMN, 200-400 nm and 100-200 nm) were administered to macrophages, chosen as cellular model due to their key role in the processing of foreign materials and the regulation of inflammatory responses. The results showed that cellular uptake of GBNs was mainly influenced by their lateral size, while the inflammatory potential depended also on the type of functionalization. PG-FMN nanomaterials (both sizes) triggered significantly higher nitric oxide (NO) release, together with some intracellular metabolic changes, similar to those induced by the prototypical inflammatory stimulus LPS. NMR metabolomics revealed that macrophages incubated with smaller PG-FMN displayed increased levels of succinate, itaconate, phosphocholine and phosphocreatine, together with decreased creatine content. The latter two variations were also detected in cells incubated with larger PG-FMN nanosheets. On the other hand, GO-PEG induced a decrease in the inflammatory metabolite succinate and a few other changes distinct from those seen in LPS-stimulated macrophages. Assessment of TNF-alpha secretion and macrophage surface markers (CD80 and CD206) further corroborated the low inflammatory potential of GO-PEG. Overall, these findings revealed distinct phenotypic and metabolic responses of macrophages to different GBNs, which inform on their immunomodulatory activity and may contribute to guide their therapeutic applications.

Enhancing the stability of spectrally selective coatings (SSC) at high temperatures in air is necessary to push the concentrated solar power (CSP) technology to the next level. To avoid failures that might not be discovered for years, advanced knowledge of the chemical properties related to the degradation mechanisms with temperature is required. For this purpose, the Mo local environment is investigated here for Mo-Si3N4 and MoSi2-Si3N4 nanocomposites SSCs. The atomic short-range order around Mo proves that MoSi2 is the stable form that appears in high temperature vacuum annealing and that MoO3 formation is associated with optical degradation in air annealing. Deposition of Al2O3 capping layers with different techniques is found of paramount relevance in the long term performance of MoSi2-Si3N4 based SSCs. MoSi2-Si3N4 hybrid composite with Al2O3 capping layer shows exceptional functional stability even after 2900 h at 600 degrees C in air. Antireflective Al2O3 layer synthesized by atomic layer deposition (ALD) shows an extraordinarily efficient protection against oxidation with unprecedented MoSi2 stability in MoSi2-Si3N4 hybrid composite, and optimum long-term optical performance. On the other hand, Al2O3 layer deposited by sputtering blocks the formation of detrimental MoO3 at 600 degrees C but allows the formation of MoO2 in MoSi2-Si3N4 for long annealing times which, however, also provides excellent and stable optical functionality related to MoO2 high stability.

Nanographene oxide (nGO)-mediated hyperthermia has been increasingly investigated as a localised, minimally invasive anticancer therapeutic approach. Near InfraRed (NIR) light irradiation for inducing hyperthermia is particularly attractive, because biological systems mostly lack chromophores that absorb in this spectral window, facilitating the selective heating and destruction of cells which have internalized the NIR absorbing-nanomaterials. However, little is known about biological effects accompanying nGO-mediated hyperthermiaat cellular and molecular levels.In this work, well-characterised pegylatednGOsheets with an hydrodynamic size of 300 nm were incubated with human Saos-2 osteosarcoma cells for 24h and their incorporation verified by flow cytometry and confocal microscopy. No effect on cell viability was observed after nGO incorporation by Saos-2 cells. However, a proliferation delay was observed due to the presence of nGO sheets in the cytoplasm.1H NMR metabolomicswas employed to screen for changes in the metabolic profile of cells, as this could help to improve understanding of celular responses to nanomaterials and provide new endpoint markers of effect.Cells incorporating nGO sheets showed noticeable changes in 10 metabolites compared to control cells, including decreased levels of several amino acids, taurine and creatine and increased levels of phosphocholine and uridine/adenosine nucleotides. After NIR irradiation, cells showed decreases in glutamate and uridine nulceotides, together with increases in glycerophosphocholine and adenosine monophosphate. Overall, this study has shown that the celular metabolome sensitively responded to nGO exposure and nGO-mediated hyperthermia and that NMR metabolomics is a powerful tool toinvestigate treatment responses.

Nanographene oxide (nGO) has been recently proposed as a new antitumoral therapeutic agent, drug delivery carrier and gene transfection vehicle, among others. Treatment is carried out by hyperthermia induced by infrared irradiation. After treatment, the nanosystems will be inevitably excreted and released to the environment. To understand the potential impacts of pegylated nGO (nGO-PEG), three key species from different trophic levels were used: the green micro-algae Raphidocelis subcapitata (growth inhibition test), the cladocera Daphnia magna (acute and chronic tests), and the fish Danio rerio (fish embryo test). Besides a regular standard procedure to assess toxicity, and considering the mode of action of nGO-PEG in cancer treatment, a simultaneous infrared lamp exposure was carried out for D. magna and D. rerio. Additionally, and taking advantage of the phenotypic transparency of D. magna, nGO-PEG was fluorescently tagged to evaluate the potential uptake of nGO-PEG. The R. subcapitata growth inhibition test showed effects during the first 48 h, recovering till the end of the test (96 h). No acute or chronic effects were observed for D. magna, under standard or infrared light exposures although confocal microscope images showed nGO-PEG uptake. Very small percentages of mortality and abnormalities were observed in D. rerio exposed with and without the infrared lamp. Although low hazard may be expected for nGO-PEG in aquatic ecosystems, further studies with species with different life traits should be accomplished, in order to derive more accurate conclusions.

A new approach for in-situ specific functionalization of graphene with carboxylic groups through a single-step growth is presented. Depending on the fabrication parameters, it is possible to synthesize functionalized single layer or multilayer graphene. The homogeneity and functionalization degree are evaluated combining micro-Raman and XPS spectroscopies. The obtained COOH content reaches around 5%, similar to the values obtained by the other methods but with significantly lower contents of the other oxygen groups (carbonyl and hydroxyl) and of other sp(3) defects which are detrimental for electronic transport. The obtained COOH-functionalized single-layer graphene presents optimum values of the sheet resistance, around 8 k Omega, and high mobility, around 800 cm(2) V(-1)s(-1). Anchoring of antibodies is demonstrated through the immobilization of IgG1-FITC by the carbodiimide method, showing that these COOH-functionalized single-layer graphene can be very promising materials for electronic sensing applications. (C) 2018 Elsevier Ltd. All rights reserved.

Bioceramic foams obtained through agri-waste products, such as egg shell and white egg recycle, represent an interesting way for waste prevention and waste management developing potentially commercial products. The aim is to design and investigate a new method to shape foams in a easy and environmental viable process. The use of egg shell as ecocompatible reactant instead of commercial ones, and the egg white as foaming agent to produce a tridimensional macroporous structures were optimized by a sol-gel route. The crystalline and quantitative phase composition were studied by Rietveld refinement, optimization of the foaming process and porosity determination by SEM and Hg porosimetry. The work demonstrated that the use of egg shell and white egg allows to obtain bioceramic foams with composition of 60wt.% HA and 40wt.% -TCP with a total porosity of 70% and a porosity ranging from 5 to 300 m. These features are ideal for bone regeneration scaffolds and heavy metal capture from polluted waters.

Nano-graphene oxide (GO) and its functionalized derivatives have aroused a great interest for drug delivery, tissue engineering and photothermal cancer therapy, but their biocompatibility has not yet been fully assessed. The aim of the present study was to evaluate the proliferation and differentiation of MC3T3-E1 pre-osteoblasts after the uptake of GO nanosheets (c.a. 400nm), functionalized with poly(ethylene glycol-amine) (PEG) and labelled with fluorescein isothiocyanate (FITC). Significant proliferation decrease and apoptosis increase were observed 3days after incorporation of FITC-PEG-GO by MC3T3-E1 cells. However, alterations on healthy pre-osteoblast differentiation into cells exhibiting osteoblast phenotype were not observed, as they showed normal alkaline phosphatase levels and matrix mineralization 12days after nanosheet uptake. The results suggest that 40μg/mL concentrations of these nanosheets would not affect the differentiation of healthy pre-osteoblasts, thus these PEG-GO nanosheets have potential to be used for biomedical applications after their internalization, as the induction of local hyperthermia on bone cancer.

The exfoliation and colloidal stabilization of layered transition metal dichalcogenides (TMDs) in an aqueous medium using functional biomolecules as dispersing agents have a number of potential benefits toward the production and practical use of the corresponding two-dimensional materials, but such a strategy has so far remained underexplored. Here, we report that DNA and RNA nucleotides are highly efficient dispersants in the preparation of stable aqueous suspensions of MoS2 and other TMD nanosheets at significant concentrations (up to 5-10 mg mL-1). Unlike the case of common surfactants, for which adsorption on 2D materials is generally based on weak dispersive forces, the exceptional colloidal stability of the TMD flakes was shown to rely on the presence of relatively strong, specific interactions of Lewis acid-base type between the DNA/RNA nucleotide molecules and the flakes. Moreover, the nucleotide-stabilized MoS2 nanosheets were shown to be efficient catalysts in the reduction of nitroarenes (4-nitrophenol and 4-nitroaniline), thus constituting an attractive alternative to the use of expensive heterogeneous catalysts based on noble metals, and exhibited an electrocatalytic activity toward the hydrogen evolution reaction that was not impaired by the possible presence of nucleotide molecules adsorbed on their active sites. The biocompatibility of these materials was also demonstrated on the basis of cell proliferation and viability assays. Overall, the present work opens new vistas on the colloidal stabilization of 2D materials based on specific interactions that could be useful toward different practical applications.

The compositional, structural and morphological recovery of α-MoO3 nanoplates implanted with Eu and Er ions has been assessed as a function of post-implantation thermal treatments. Rapid thermal annealing induces the formation of phases different from α-MoO3 and seems to be unable to recover the original oxygen content of the nanostructures. In contrast, conventional annealing in air at 450 °C for 4 hours fully recovers the original molybdenum trioxide structure and leads to an effective optical activation of both Er and Eu ions. Synchrotron-based X-ray photoelectron spectroscopy and X-ray absorption studies confirm the incorporation of the rare earth ions into their trivalent charge state and reveal the modification of the original valence band structure of the nanoplates.

The current study reports on the manufacturing by rapid prototyping technique of three-dimensional (3D) scaffolds based on silicon substituted hydroxyapatite with Elastin-like Recombinamers (ELRs) functionalized surfaces. Silicon doped hydroxyapatite (Si-HA), with Ca-10(PO4)(5.7)(SiO4)(0.3)(OH)(1.7)h(0.3) nominal formula, was surface functionalized with two different types of polymers designed by genetic engineering: ELR-RGD that contain cell attachment specific sequences and ELR-SNA15/RGD with both hydroxyapatite and cells domains that interact with the inorganic phase and with the cells, respectively. These hybrid materials were subjected to in vitro assays in order to clarify if the ELRs coating improved the well-known biocompatible and bone regeneration properties of calcium phosphates materials. The in vitro tests showed that there was a total and homogeneous colonization of the 3D scaffolds by Bone marrow Mesenchymal Stromal Cells (BMSCs). In addition, the BMSCs were viable and able to proliferate and differentiate into osteoblasts.Statement of SignificanceBone tissue engineering is an area of increasing interest because its main applications are directly related to the rising life expectancy of the population, which promotes higher rates of several bone pathologies, so innovative strategies are needed for bone tissue regeneration therapies. Here we use the rapid prototyping technology to allow moulding ceramic 3D scaffolds and we use different bio-polymers for the functionalization of their surfaces in order to enhance the biological response. Combining the ceramic material (silicon doped hydroxyapatite, Si-HA) and the Elastin like Recombinamers (ELRs) polymers with the presence of the integrin-mediate adhesion domain alone or in combination with SNAI 5 peptide that possess high affinity for hydroxyapatite, provided an improved Bone marrow Mesenchymal Stromal Cells (BMSCs) differentiation into osteoblastic linkage. (C) 2016 Acta Materialia Inc. Published by Elsevier Ltd. All rights reserved.

The functionalization of nanographene oxide (GO) with polymers is desirable for increasing the interface compatibility of GO, thereby enabling its use in a variety of applications such as biomedical and energy storage systems. Typically, wet chemistry processes are used to achieve polymer functionalization of GO, having limitations of high heterogeneity, time consumption, and difficult purification processes. Two approaches for dry functionalization of the nano-GO surface are therefore proposed, utilizing an atomic layer deposition (ALD) reactor: (1) vaporization-condensation of polyethylene glycol amine (PEG-NH2) and (ii) molecular layer deposition (MLD) of a polymer hybrid from trimethylaluminum (TMA) and ethylene glycol (EG). Carboxylic activated nano-GO (GO-COON) powders were exposed to PEG at variable temperatures, determining that a minimum of 100 degrees C was sufficient for adsorption of the polymer. In addition, a layer by layer deposition (an MLD route) is proposed to impart control over the growth of a polymer hybrid onto the GO COOH surface and to enhance the efficiency of polymer deposition by sequentially supplying a passivation layer, -Al- bonds, for monomer attachment. FTIR and XPS results showed effective control on the growth of the hybrid polymer at the GO COOH surface, achieved through optimization of ALD reactor experimental conditions.

A novel technology for the preparation of bioceramic foams (BF) using a simple and economic procedure is presented. This technology combines two conventional methods to produce a tridimensional macroporous structure by using a sol–gel route, submitted afterward to a microwave treatment and thermal annealing. The use of agri-waste products on this procedure, such as egg shell and white egg recycle, represents an interesting way for waste management while developing potential commercial biomaterials. The use of egg shell as eco-compatible reactant instead of commercial ones and the egg white as foaming agent to produce a tridimensional macroporous structures has been optimized by using a sol–gel route. The crystalline phase and quantitative phase composition has been studied by Rietveld refinement and the optimization of the foaming process and determination of interconnected porosity by scanning electron microscopy, Hg porosimetry and X-ray micro-CT imaging. Our results show that BF samples showed a composition of 60 wt% HA (hydroxyapatite) and 40 wt% β-TCP (β-tricalcium phosphate) with a total porosity of approx. 70 % and a porosity ranging from 5 to 300 μm. These features indicate that BF samples are ideal for bone regeneration, and they are produced in an easy and environmental friendly viable process.

The nanocarbon allotropes constitute valid alternatives when designing control and actuation devices for electrically assisted tissue regeneration purposes, gathering among them important characteristics such as chemical inertness, biocompatibility, extreme mechanical properties, and, importantly, low and tailorable electrical resistivity. In this work, coatings of thin (100 nm) vertically aligned nanoplatelets composed of diamond (5 nm) and graphite were produced via a microwave plasma chemical vapor deposition (MPCVD) technique and used as substrates for electrical stimulation of MC3T3-E1 preosteoblasts. Increasing the amount of N2 up to 14.5 vol % during growth lowers the coatings' electrical resistivity by over 1 order of magnitude, triggers the nanoplatelet vertical growth, and leads to the higher crystalline quality of the nanographite phase. When preosteoblasts were cultured on these substrates and subjected to two consecutive daily cycles of 3 μA direct current stimulation, enhanced cell proliferation and metabolism were observed accompanied by high cell viability. Furthermore, in the absence of DC stimulation, alkaline phosphatase (ALP) activity is increased significantly, denoting an up-regulating effect of preosteoblastic maturation intrinsically exerted by the nanoplatelet substrates.