Betanin is the only betalain approved for use in food and pharmaceutical products as a natural red colorant. However, the antioxidant power and health-promoting properties of this pigment have been ...disregarded, perhaps due to the difficulty in obtaining a stable chemical compound, which impairs its absorption and metabolism evaluation. Herein, betanin was purified by semi-preparative HPLC-LC/MS and identified by LC-ESI(+)-MS/MS as the pseudomolecular ion
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551.16. Betanin showed significant stability up to -30 °C and mild stability at chilling temperature. The stability and antioxidant ability of this compound were assessed during a human digestion simulation and ex vivo colon fermentation. Half of the betanin amount was recovered in the small intestine digestive fluid and no traces were found after colon fermentation. Betanin high antioxidant ability was retained even after simulated small intestine digestion. Betanin, besides displaying an inherent colorant capacity, was equally effective as a natural antioxidant displaying peroxy-radical scavenger ability in pork meat. Betanin should be considered a multi-functional molecule able to confer an attractive color to frozen or refrigerated foods, but with the capacity to avoid lipid oxidation, thereby preserving food quality. Long-term supplementation by beetroot, a rich source of betanin, should be stimulated to protect organisms against oxidative stress.
The additive‐manufacturing (AM) technique, known as three‐dimensional (3D) printing, has attracted much attention in industry and academia in recent years. 3D printing has been developed for a ...variety of applications. Printable inks are the most important component for 3D printing, and are related to the materials, the printing method, and the structures of the final 3D‐printed products. Carbon materials, due to their good chemical stability and versatile nanostructure, have been widely used in 3D printing for different applications. Good inks are mainly based on volatile solutions having carbon materials as fillers such as graphene oxide (GO), carbon nanotubes (CNT), carbon blacks, and solvent, as well as polymers and other additives. Studies of carbon materials in 3D printing, especially GO‐based materials, have been extensively reported for energy‐related applications. In these circumstances, understanding the very recent developments of 3D‐printed carbon materials and their extended applications to address energy‐related challenges and bring new concepts for material designs are becoming urgent and important. Here, recent developments in 3D printing of emerging devices for energy‐related applications are reviewed, including energy‐storage applications, electronic circuits, and thermal‐energy applications at high temperature. To close, a conclusion and outlook are provided, pointing out future designs and developments of 3D‐printing technology based on carbon materials for energy‐related applications and beyond.
The additive manufacturing (AM) technique, known as three‐dimensional (3D) printing, has attracted much attention in industry and academia in recent years. Understanding the very recent development of 3D‐printed carbon materials and its extended applications to address energy‐related challenges is becoming urgent and important. Recent developments of 3D‐printed carbon materials for energy‐related applications are reviewed, including energy storage, electronic circuits, and thermal‐energy applications at high temperature.
Water samples from agricultural drains were tested for the presence of nonylphenol and nonylphenol mono- and diethoxylates. The analytes belong to biodegradation products of long-chained nonylphenol ...ethoxylates, which are used as additives in pesticide formulations. Quantification of these analytes was performed by HPLC with fluorescence detection after isolation by using multi-capillary polytetrafluoroethylene (PTFE) trap extraction. This newly developed technique allowed obtaining about 90% recovery of these analytes in synthetic samples and several percent lower recovery in real samples. Also, no additional sample cleaning was needed before chromatographic analysis. The limit of quantitation for all the analytes was 0.1kgL super(-) super(1). The nonylphenol, nonylphenol mono- and diethoxylates were detected at the concentrations ranging from 0.5 to 6.0kgL super(-) super(1), from 0.2 to 0.7kgL super(-) super(1) and from below 0.02 to 0.4kgL super(-) super(1), respectively. Concentrations of nonylphenol and its derivatives were higher in samples taken in spring than in summer.
The presence, dissolution, agglomeration state, and release of materials in the nano-size range from food containing engineered nanoparticles during human digestion is a key question for the safety ...assessment of these materials. We used an in vitro model to mimic the human digestion. Food products subjected to in vitro digestion included (i) hot water, (ii) coffee with powdered creamer, (iii) instant soup, and (iv) pancake which either contained silica as the food additive E551, or to which a form of synthetic amorphous silica or 32 nm SiO2 particles were added. The results showed that, in the mouth stage of the digestion, nano-sized silica particles with a size range of 5–50 and 50–500 nm were present in food products containing E551 or added synthetic amorphous silica. However, during the successive gastric digestion stage, this nano-sized silica was no longer present for the food matrices coffee and instant soup, while low amounts were found for pancakes. Additional experiments showed that the absence of nano-sized silica in the gastric stage can be contributed to an effect of low pH combined with high electrolyte concentrations in the gastric digestion stage. Large silica agglomerates are formed under these conditions as determined by DLS and SEM experiments and explained theoretically by the extended DLVO theory. Importantly, in the subsequent intestinal digestion stage, the nano-sized silica particles reappeared again, even in amounts higher than in the saliva (mouth) digestion stage. These findings suggest that, upon consumption of foods containing E551, the gut epithelium is most likely exposed to nano-sized silica.
Tribological performance of polyalphaolefin 32, PAO, is investigated by adding two nanomaterials (graphene nanoplatelets, GnP, and hexagonal boron nitride nanoparticles, h-BN) and an ionic liquid ...(P6,6,6,14DEHP, IL1, P2,4,4,4DEP, IL2, or P6,6,6,14(iC8)2PO2, IL3). Designed double hybrid nanodispersions are PAO/1 wt% ILX/0.05 wt% GnP/0.1 wt% h-BN (X = 1, 2 or 3). The best anti-friction behavior corresponds to PAO/IL3/GnP/h-BN (40% reduction compared to that achieved with PAO). Anti-wear behavior is similar for the three double hybrid nanodispersions. Roughness of the worn surface tested with PAO is higher than that obtained for each of the nanodispersions. Tribo-film formation and repair effect on worn surfaces due to ILs and nanoparticles are revealed. Some positive synergies were found between each IL and GnP/h-BN as hybrid PAO additives.
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•Three ILs combined with h-BN/GnP as hybrid additives of PAO32 were analyzed.•PAO/ILX/GnP/h-BN improve the tribological behavior of PAO32 and of single additives.•40% friction reduction with 1 wt% IL3 + 0.1 wt% h-BN + 0.05 wt% GnP added to PAO32.•18% worn area reduction with 1 wt% IL1 + 0.1 wt% h-BN + 0.05 wt% GnP added to PAO32.•Tribofilm formation on worn surfaces formed by ILs and/or nanoadditives.
Engineered nanomaterials (ENM) are used extensively in food products to fulfill a number of roles, including enhancement of color and texture, for nutritional fortification, enhanced bioavailability, ...improved barrier properties of packaging, and enhanced food preservation. Safety assessment of ingested engineered nanomaterials (iENM) has gained interest in the nanotoxicology community in recent years. A variety of test systems and approaches have been used for such evaluations, with in vitro monoculture cell models being the most common test systems, owing to their low cost and ease-of-use. The goal of this review is to systematically assess the current state of science in toxicological testing of iENM, with particular emphasis on model test systems, their physiological relevance, methodological strengths and challenges, realistic doses (ranges and rates), and then to identify future research needs and priorities based on these assessments.
Extensive searches were conducted in Google Scholar, PubMed and Web of Science to identify peer-reviewed literature on safety assessment of iENM over the last decade, using keywords such as "nanoparticle", "food", "toxicity", and combinations thereof. Relevant literature was assessed based on a set of criteria that included the relevance of nanomaterials tested; ENM physicochemical and morphological characterization; dispersion and dosimetry in an in vitro system; dose ranges employed, the rationale and dose realism; dissolution behavior of iENM; endpoints tested, and the main findings of each study. Observations were entered into an excel spreadsheet, transferred to Origin, from where summary statistics were calculated to assess patterns, trends, and research gaps.
A total of 650 peer-reviewed publications were identified from 2007 to 2017, of which 39 were deemed relevant. Only 21% of the studies used food grade nanomaterials for testing; adequate physicochemical and morphological characterization was performed in 53% of the studies. All in vitro studies lacked dosimetry and 60% of them did not provide a rationale for the doses tested and their relevance. Only 12% of the studies attempted to consider the dissolution kinetics of nanomaterials. Moreover, only 1 study attempted to prepare and characterize standardized nanoparticle dispersions.
We identified 5 clusters of factors deemed relevant to nanotoxicology of food-grade iENM: (i) using food-grade nanomaterials for toxicity testing; (ii) performing comprehensive physicochemical and morphological characterization of iENM in the dry state, (iii) establishing standard NP dispersions and their characterization in cell culture medium, (iv) employing realistic dose ranges and standardized in vitro dosimetry models, and (v) investigating dissolution kinetics and biotransformation behavior of iENM in synthetic media representative of the gastrointestinal (GI) tract fluids, including analyses in a fasted state and in the presence of a food matrix. We discussed how these factors, when not considered thoughtfully, could influence the results and generalizability of in vitro and in vivo testing. We conclude with a set of recommendations to guide future iENM toxicity studies and to develop/adopt more relevant in vitro model systems representative of in vivo animal and human iENM exposure scenarios.
Additive manufacturing of metals Herzog, Dirk; Seyda, Vanessa; Wycisk, Eric ...
Acta materialia,
09/2016, Volume:
117
Journal Article
Peer reviewed
Open access
Additive Manufacturing (AM), the layer-by layer build-up of parts, has lately become an option for serial production. Today, several metallic materials including the important engineering materials ...steel, aluminium and titanium may be processed to full dense parts with outstanding properties.
In this context, the present overview article describes the complex relationship between AM processes, microstructure and resulting properties for metals. It explains the fundamentals of Laser Beam Melting, Electron Beam Melting and Laser Metal Deposition, and introduces the commercially available materials for the different processes. Thereafter, typical microstructures for additively manufactured steel, aluminium and titanium are presented. Special attention is paid to AM specific grain structures, resulting from the complex thermal cycle and high cooling rates. The properties evolving as a consequence of the microstructure are elaborated under static and dynamic loading. According to these properties, typical applications are presented for the materials and methods for conclusion.
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The need for energy efficiency is leading to the growing use of additives that reduce friction in thin film boundary and mixed lubrication conditions. Several classes of such friction modifier ...additive exist, the main ones being organic friction modifiers, functionalised polymers, soluble organo-molybdenum additives and dispersed nanoparticles. All work in different ways. This paper reviews these four main types of lubricant friction modifier additive and outlines their history, research and the mechanisms by which they are currently believed to function. Aspects of their behaviour that are still not yet fully understood are highlighted.
Hot melt extrusion (HME) has been widely used for producing amorphous solid dispersions (ASD). There is an extensive body of literature on the pharmaceutical applications of solid dispersions ...produced by HME for improving the dissolution rates of poorly soluble drugs, but most systems are either binary polymer-drug or ternary polymer-drug-surfactant mixtures. There is still limited number of studies exploring the use of low quantities of functional additives in hot melt extruded solid dispersions to (1) tune the drug release rate from the formulations (for either immediate release or controlled release applications) and (2) to increase the drug loading capacity. The aim of this project is to develop fundamental understanding and formulation strategies in order to achieve these two new capabilities. Such knowledge has excellent potential to extend the application of solid dispersions for a much wider range of products. Firstly, to develop tuneable drug release capability of ASD produced via HME, this project used carbamazepine as the model drug and HPMCAS as the base formulation and a range of low-quantity functional additives to investigate for their abilities to alter the drug release rate of the extrudates. We developed in depth understanding of the effects of these additives on the control of internal microstructure of HME extrudates. Secondly, to develop innovative approaches to increase the drug loading of ASD without compromising physical stability, we used tolbutamide as the model drug and Soluplus as the base formulation and mesoporous silica (MPS) as the functional additive. The results indicated the potential and limitations of MPS as a functional excipient for increasing drug loading in ASD prepared by HME. In this project, all hot melt extruded ASDs were characterised using conventional techniques including DSC, MTDSC, TGA, ATR-FTIR, PXRD, SEM, EDS, XμCT, in-vitro dissolution testing. Novel UV-imaging methodology was developed and performed on carbamazepine-loaded ASDs which facilitated the understand of the in-vitro dissolution behaviour of the ASDs. The results of this project demonstrate the practicality of using low-quality functional additives in a single-step hot melt extrusion (HME) process to tune drug release behaviour and drug loading of ASDs which can bring new insights into the industrial applications of HME and ASDs.
Since most starting materials for tissue engineering are in powder form, using powder-based additive manufacturing methods is attractive and practical. The principal point of employing additive ...manufacturing (AM) systems is to fabricate parts with arbitrary geometrical complexity with relatively minimal tooling cost and time. Selective laser sintering (SLS) and inkjet 3D printing (3DP) are two powerful and versatile AM techniques which are applicable to powder-based material systems. Hence, the latest state of knowledge available on the use of AM powder-based techniques in tissue engineering and their effect on mechanical and biological properties of fabricated tissues and scaffolds must be updated. Determining the effective setup of parameters, developing improved biocompatible/bioactive materials, and improving the mechanical/biological properties of laser sintered and 3D printed tissues are the three main concerns which have been investigated in this article.
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