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Materials, Volume 7, Issue 9 (September 2014), Pages 6105-6892

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Open AccessArticle Diffusion and Interface Effects during Preparation of All-Solid Microstructured Fibers
Materials 2014, 7(9), 6879-6892; https://doi.org/10.3390/ma7096879
Received: 25 June 2014 / Revised: 15 September 2014 / Accepted: 19 September 2014 / Published: 25 September 2014
Cited by 2 | PDF Full-text (1546 KB) | HTML Full-text | XML Full-text
Abstract
All-solid microstructured optical fibers (MOF) allow the realization of very flexible optical waveguide designs. They are prepared by stacking of doped silica rods or canes in complex arrangements. Typical dopants in silica matrices are germanium and phosphorus to increase the refractive index (RI),
[...] Read more.
All-solid microstructured optical fibers (MOF) allow the realization of very flexible optical waveguide designs. They are prepared by stacking of doped silica rods or canes in complex arrangements. Typical dopants in silica matrices are germanium and phosphorus to increase the refractive index (RI), or boron and fluorine to decrease the RI. However, the direct interface contact of stacking elements often causes interrelated chemical reactions or evaporation during thermal processing. The obtained fiber structures after the final drawing step thus tend to deviate from the targeted structure risking degrading their favored optical functionality. Dopant profiles and design parameters (e.g., the RI homogeneity of the cladding) are controlled by the combination of diffusion and equilibrium conditions of evaporation reactions. We show simulation results of diffusion and thermal dissociation in germanium and fluorine doped silica rod arrangements according to the monitored geometrical disturbances in stretched canes or drawn fibers. The paper indicates geometrical limits of dopant structures in sub-µm-level depending on the dopant concentration and the thermal conditions during the drawing process. The presented results thus enable an optimized planning of the preform parameters avoiding unwanted alterations in dopant concentration profiles or in design parameters encountered during the drawing process. Full article
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Open AccessArticle A Novel Exploration of a Combination of Gambogic Acid with TiO2 Nanofibers: The Photodynamic Effect for HepG2 Cell Proliferation
Materials 2014, 7(9), 6865-6878; https://doi.org/10.3390/ma7096865
Received: 17 July 2014 / Revised: 28 August 2014 / Accepted: 28 August 2014 / Published: 24 September 2014
Cited by 5 | PDF Full-text (496 KB) | HTML Full-text | XML Full-text | Supplementary Files
Abstract
As a good photosensitizer, TiO2 nanomaterials show potential biomedical applications, such as drug carriers or enhancers in photodynamic therapy. In this contribution, novel nanocomposites through the blending of TiO2 nanofibers with the active compound, gambogic acid (GA), were explored, and the
[...] Read more.
As a good photosensitizer, TiO2 nanomaterials show potential biomedical applications, such as drug carriers or enhancers in photodynamic therapy. In this contribution, novel nanocomposites through the blending of TiO2 nanofibers with the active compound, gambogic acid (GA), were explored, and the results showed that GA could inhibit cancer cell proliferation in a time-dependent and dose-dependent manner, inducing apoptosis and cell cycle arrest at the G0/G1 phase in HepG2 cells. It is evident that after the GA-TiO2 nanocomposites were cultured with the cancer cells, the cooperation effect could effectively enhance the cytotoxicity of GA for HepG2 cells. Meanwhile, if activated by UV irradiation, under the presence of GA-TiO2 nanocomposites, this would lead to significant apoptosis and necrosis for HepG2 cells with a photodynamic therapy (PDT) effect. Associated with the controlled drug-release from these nanocomposites, TiO2 nanofibers could readily cut down the drug consumption in HepG2 cells and reduce the side-effect for the normal cells and tissue, which may be further utilized in the therapeutic alliance for cancer therapy. Full article
(This article belongs to the Special Issue Materials for Drug Delivery)
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Open AccessArticle Evaluation of Binding Effects in Wood Flour Board Containing Ligno-Cellulose Nanofibers
Materials 2014, 7(9), 6853-6864; https://doi.org/10.3390/ma7096853
Received: 30 May 2014 / Revised: 22 August 2014 / Accepted: 19 September 2014 / Published: 22 September 2014
Cited by 8 | PDF Full-text (639 KB) | HTML Full-text | XML Full-text
Abstract
Wood-based materials are used extensively in residual construction worldwide. Most of the adhesives used in wood-based materials are derived from fossil resources, and some are not environmentally friendly. This study explores nanofiber technology as an alternative to such adhesives. Previous studies have shown
[...] Read more.
Wood-based materials are used extensively in residual construction worldwide. Most of the adhesives used in wood-based materials are derived from fossil resources, and some are not environmentally friendly. This study explores nanofiber technology as an alternative to such adhesives. Previous studies have shown that the three-dimensional binding effects of cellulose nanofiber (CNF), when mixed with wood flour, can significantly improve the physical and mechanical properties of wood flour board. In this study, ligno-cellulose nanofibers (LCNF) were fabricated by wet disk milling of wood flour. Composite boards of wood flour and LCNF were produced to investigate the binding effect(s) of LCNF. The fabrication of LCNF by disk milling was simple and effective, and its incorporation into wood flour board significantly enhanced the physical and mechanical properties of the board. Full article
(This article belongs to the Special Issue Advances in Cellulosic Materials 2014)
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Open AccessCommunication A Label-Free Immunosensor for IgG Based on an Extended-Gate Type Organic Field Effect Transistor
Materials 2014, 7(9), 6843-6852; https://doi.org/10.3390/ma7096843
Received: 31 July 2014 / Revised: 7 September 2014 / Accepted: 16 September 2014 / Published: 22 September 2014
Cited by 23 | PDF Full-text (2283 KB) | HTML Full-text | XML Full-text
Abstract
A novel biosensor for immunoglobulin G (IgG) detection based on an extended-gate type organic field effect transistor (OFET) has been developed that possesses an anti-IgG antibody on its extended-gate electrode and can be operated below 3 V. The titration results from the target
[...] Read more.
A novel biosensor for immunoglobulin G (IgG) detection based on an extended-gate type organic field effect transistor (OFET) has been developed that possesses an anti-IgG antibody on its extended-gate electrode and can be operated below 3 V. The titration results from the target IgG in the presence of a bovine serum albumin interferent, clearly exhibiting a negative shift in the OFET transfer curve with increasing IgG concentration. This is presumed to be due an interaction between target IgG and the immobilized anti-IgG antibody on the extended-gate electrode. As a result, a linear range from 0 to 10 µg/mL was achieved with a relatively low detection limit of 0.62 µg/mL (=4 nM). We believe that these results open up opportunities for applying extended-gate-type OFETs to immunosensing. Full article
(This article belongs to the Special Issue Organic Transistor)
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Open AccessArticle Cold-Curing Structural Epoxy Resins: Analysis of the Curing Reaction as a Function of Curing Time and Thickness
Materials 2014, 7(9), 6832-6842; https://doi.org/10.3390/ma7096832
Received: 23 July 2014 / Revised: 22 August 2014 / Accepted: 5 September 2014 / Published: 22 September 2014
Cited by 8 | PDF Full-text (570 KB) | HTML Full-text | XML Full-text
Abstract
The curing reaction of a commercial cold-curing structural epoxy resin, specifically formulated for civil engineering applications, was analyzed by thermal analysis as a function of the curing time and the sample thickness. Original and remarkable results regarding the effects of curing time on
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The curing reaction of a commercial cold-curing structural epoxy resin, specifically formulated for civil engineering applications, was analyzed by thermal analysis as a function of the curing time and the sample thickness. Original and remarkable results regarding the effects of curing time on the glass transition temperature and on the residual heat of reaction of the cold-cured epoxy were obtained. The influence of the sample thickness on the curing reaction of the cold-cured resin was also deeply investigated. A highly exothermal reaction, based on a self-activated frontal polymerization reaction, was supposed and verified trough a suitable temperature signal acquisition system, specifically realized for this measurement. This is one of the first studies carried out on the curing behavior of these peculiar cold-cured epoxy resins as a function of curing time and thickness. Full article
(This article belongs to the Section Advanced Composites)
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Open AccessArticle Optimization of Aluminum Stressed Skin Panels in Offshore Applications
Materials 2014, 7(9), 6811-6831; https://doi.org/10.3390/ma7096811
Received: 28 February 2014 / Revised: 18 April 2014 / Accepted: 3 September 2014 / Published: 19 September 2014
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Abstract
Since the introduction of general European rules for the design of aluminium structures, specific rules for the design of aluminum stressed skin panels are available. These design rules have been used for the optimization of two extrusion products: one for explosions and wind
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Since the introduction of general European rules for the design of aluminium structures, specific rules for the design of aluminum stressed skin panels are available. These design rules have been used for the optimization of two extrusion products: one for explosions and wind load governing and one for explosions and floor load governing. The optimized extrusions fulfill Class 3 section properties, leading to weight reductions up to 25% of regularly-used shear panel sections. When the design is based on Class 4 section properties, even more weight reduction may be reached. The typical failure mode of the optimized stressed skin panels depends on the applied height of the hat stiffeners. For sections using relatively high hat stiffeners, failure is introduced by yielding of the heat-affected zone. For this type of cross-section, Eurocode 9 design rules and numerical calculations show very good agreement. For sections using relatively low hat stiffeners, failure is introduced by global buckling. For this type of cross-section, Eurocode 9 gives rather conservative results. Full article
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Open AccessArticle Fabrication of Aluminum Foam-Filled Thin-Wall Steel Tube by Friction Welding and Its Compression Properties
Materials 2014, 7(9), 6796-6810; https://doi.org/10.3390/ma7096796
Received: 18 July 2014 / Revised: 25 August 2014 / Accepted: 16 September 2014 / Published: 19 September 2014
Cited by 12 | PDF Full-text (1287 KB) | HTML Full-text | XML Full-text
Abstract
Aluminum foam has received considerable attention in various fields and is expected to be used as an engineering material owing to its high energy absorption properties and light weight. To improve the mechanical properties of aluminum foam, combining it with dense tubes, such
[...] Read more.
Aluminum foam has received considerable attention in various fields and is expected to be used as an engineering material owing to its high energy absorption properties and light weight. To improve the mechanical properties of aluminum foam, combining it with dense tubes, such as aluminum foam-filled tubes, was considered necessary. In this study, an aluminum foam-filled steel tube, which consisted of ADC12 aluminum foam and a thin-wall steel tube, was successfully fabricated by friction welding. It was shown that a diffusion bonding layer with a thickness of approximately 10 μm was formed, indicating that strong bonding between the aluminum foam and the steel tube was realized. By the X-ray computed tomography observation of pore structures, the fabrication of an aluminum foam-filled tube with almost uniform pore structures over the entire specimen was confirmed. In addition, it was confirmed that the aluminum foam-filled steel tube exhibited mechanical properties superior to those of the ADC12 aluminum foam and steel tube. This is considered to be attributed to the combination of the aluminum foam and steel tube, which particularly prevents the brittle fracture and collapse of the ADC12 foam by the steel tube, along with the strong metal bonding between the aluminum foam and the steel tube. Full article
(This article belongs to the Section Porous Materials)
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Open AccessArticle Preparation and Characterization of Injectable Brushite Filled-Poly (Methyl Methacrylate) Bone Cement
Materials 2014, 7(9), 6779-6795; https://doi.org/10.3390/ma7096779
Received: 4 August 2014 / Revised: 6 September 2014 / Accepted: 15 September 2014 / Published: 19 September 2014
Cited by 10 | PDF Full-text (1629 KB) | HTML Full-text | XML Full-text
Abstract
Powder-liquid poly (methyl methacrylate) (PMMA) bone cements are widely utilized for augmentation of bone fractures and fixation of orthopedic implants. These cements typically have an abundance of beneficial qualities, however their lack of bioactivity allows for continued development. To enhance osseointegration and bioactivity,
[...] Read more.
Powder-liquid poly (methyl methacrylate) (PMMA) bone cements are widely utilized for augmentation of bone fractures and fixation of orthopedic implants. These cements typically have an abundance of beneficial qualities, however their lack of bioactivity allows for continued development. To enhance osseointegration and bioactivity, calcium phosphate cements prepared with hydroxyapatite, brushite or tricalcium phosphates have been introduced with rather unsuccessful results due to increased cement viscosity, poor handling and reduced mechanical performance. This has limited the use of such cements in applications requiring delivery through small cannulas and in load bearing. The goal of this study is to design an alternative cement system that can better accommodate calcium-phosphate additives while preserving cement rheological properties and performance. In the present work, a number of brushite-filled two-solution bone cements were prepared and characterized by studying their complex viscosity-versus-test frequency, extrusion stress, clumping tendency during injection through a syringe, extent of fill of a machined void in cortical bone analog specimens, and compressive strength. The addition of brushite into the two-solution cement formulations investigated did not affect the pseudoplastic behavior and handling properties of the materials as demonstrated by rheological experiments. Extrusion stress was observed to vary with brushite concentration with values lower or in the range of control PMMA-based cements. The materials were observed to completely fill pre-formed voids in bone analog specimens. Cement compressive strength was observed to decrease with increasing concentration of fillers; however, the materials exhibited high enough strength for consideration in load bearing applications. The results indicated that partially substituting the PMMA phase of the two-solution cement with brushite at a 40% by mass concentration provided the best combination of the properties investigated. This alternative material may find applications in systems requiring highly injectable and viscous cements such as in the treatment of spinal fractures and bone defects. Full article
(This article belongs to the Section Biomaterials)
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Open AccessArticle Sol-Gel Synthesis and Antioxidant Properties of Yttrium Oxide Nanocrystallites Incorporating P-123
Materials 2014, 7(9), 6768-6778; https://doi.org/10.3390/ma7096768
Received: 25 June 2014 / Revised: 30 August 2014 / Accepted: 5 September 2014 / Published: 19 September 2014
Cited by 7 | PDF Full-text (1184 KB) | HTML Full-text | XML Full-text
Abstract
Yttrium oxide (Y2O3) nanocrystallites were synthesized by mean of a sol-gel method using two different precursors. Raw materials used were yttrium nitrate and yttrium chloride, in methanol. In order to promote oxygen vacancies, P-123 poloxamer was incorporated. Synthesized systems
[...] Read more.
Yttrium oxide (Y2O3) nanocrystallites were synthesized by mean of a sol-gel method using two different precursors. Raw materials used were yttrium nitrate and yttrium chloride, in methanol. In order to promote oxygen vacancies, P-123 poloxamer was incorporated. Synthesized systems were heat-treated at temperatures from 700 °C to 900 °C. Systems at 900 °C were prepared in the presence and absence of P-123 using different molar ratios (P-123:Y = 1:1 and 2:1). Fourier transform infrared spectroscopy (FTIR) results revealed a characteristic absorption band of Y–O vibrations typical of Y2O3 matrix. The structural phase was analyzed by X-ray diffraction (XRD), showing the characteristic cubic phase in all systems. The diffraction peak that presented the major intensity corresponded to the sample prepared from yttrium chloride incorporating P-123 in a molar ratio of P-123:Y = 2:1 at 900 °C. Crystallites sizes were determined by Scherrer equation as between 21 nm and 32 nm. Antioxidant properties were estimated by 2,2-diphenyl-1-picrylhydrazyl (DPPH•) assays; the results are discussed. Full article
(This article belongs to the Special Issue Selected Papers from the 1st International e-Conference on Materials)
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Open AccessArticle Matrix Structure Evolution and Nanoreinforcement Distribution in Mechanically Milled and Spark Plasma Sintered Al-SiC Nanocomposites
Materials 2014, 7(9), 6748-6767; https://doi.org/10.3390/ma7096748
Received: 13 June 2014 / Revised: 30 August 2014 / Accepted: 9 September 2014 / Published: 19 September 2014
Cited by 13 | PDF Full-text (2772 KB) | HTML Full-text | XML Full-text
Abstract
Development of homogenous metal matrix nanocomposites with uniform distribution of nanoreinforcement, preserved matrix nanostructure features, and improved properties, was possible by means of innovative processing techniques. In this work, Al-SiC nanocomposites were synthesized by mechanical milling and consolidated through spark plasma sintering. Field
[...] Read more.
Development of homogenous metal matrix nanocomposites with uniform distribution of nanoreinforcement, preserved matrix nanostructure features, and improved properties, was possible by means of innovative processing techniques. In this work, Al-SiC nanocomposites were synthesized by mechanical milling and consolidated through spark plasma sintering. Field Emission Scanning Electron Microscope (FE-SEM) with Energy Dispersive X-ray Spectroscopy (EDS) facility was used for the characterization of the extent of SiC particles’ distribution in the mechanically milled powders and spark plasma sintered samples. The change of the matrix crystallite size and lattice strain during milling and sintering was followed through X-ray diffraction (XRD). The density and hardness of the developed materials were evaluated as function of SiC content at fixed sintering conditions using a densimeter and a digital microhardness tester, respectively. It was found that milling for 24 h led to uniform distribution of SiC nanoreinforcement, reduced particle size and crystallite size of the aluminum matrix, and increased lattice strain. The presence and amount of SiC reinforcement enhanced the milling effect. The uniform distribution of SiC achieved by mechanical milling was maintained in sintered samples. Sintering led to the increase in the crystallite size of the aluminum matrix; however, it remained less than 100 nm in the composite containing 10 wt.% SiC. Density and hardness of sintered nanocomposites were reported and compared with those published in the literature. Full article
(This article belongs to the Section Structure Analysis and Characterization)
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Open AccessArticle Preparation and Characterization of Lignocellulosic Oil Sorbent by Hydrothermal Treatment of Populus Fiber
Materials 2014, 7(9), 6733-6747; https://doi.org/10.3390/ma7096733
Received: 17 July 2014 / Revised: 7 September 2014 / Accepted: 11 September 2014 / Published: 18 September 2014
Cited by 12 | PDF Full-text (1128 KB) | HTML Full-text | XML Full-text
Abstract
This study is aimed at achieving the optimum conditions of hydrothermal treatment and acetylation of Populus fiber to improve its oil sorption capacity (OSC) in an oil-water mixture. The characteristics of the hydrolyzed and acetylated fibers were comparatively investigated by FT-IR, CP-MAS 13
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This study is aimed at achieving the optimum conditions of hydrothermal treatment and acetylation of Populus fiber to improve its oil sorption capacity (OSC) in an oil-water mixture. The characteristics of the hydrolyzed and acetylated fibers were comparatively investigated by FT-IR, CP-MAS 13C-NMR, SEM and TGA. The optimum conditions of the hydrothermal treatment and acetylation were obtained at170 °C for 1 h and 120 °C for 2 h, respectively. The maximum OSC of the hydrolyzed fiber (16.78 g/g) was slightly lower than that of the acetylated fiber (21.57 g/g), but they were both higher than the maximum OSC of the unmodified fiber (3.94 g/g). In addition, acetylation after hydrothermal treatment for the Populus fiber was unnecessary as the increment of the maximum OSC was only 3.53 g/g. The hydrolyzed and the acetylated Populus fibers both displayed a lumen orifice enabling a high oil entrapment. The thermal stability of the modified fibers was shown to be increased in comparison with that of the raw fiber. The hydrothermal treatment offers a new approach to prepare lignocellulosic oil sorbent. Full article
(This article belongs to the Special Issue Advances in Cellulosic Materials 2014)
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Open AccessReview Review on Polymers for Thermoelectric Applications
Materials 2014, 7(9), 6701-6732; https://doi.org/10.3390/ma7096701
Received: 30 May 2014 / Revised: 23 August 2014 / Accepted: 5 September 2014 / Published: 18 September 2014
Cited by 71 | PDF Full-text (3268 KB) | HTML Full-text | XML Full-text
Abstract
In this review, we report the state-of-the-art of polymers in thermoelectricity. Classically, a number of inorganic compounds have been considered as the best thermoelectric materials. Since the prediction of the improvement of the figure of merit by means of electronic confinement in 1993,
[...] Read more.
In this review, we report the state-of-the-art of polymers in thermoelectricity. Classically, a number of inorganic compounds have been considered as the best thermoelectric materials. Since the prediction of the improvement of the figure of merit by means of electronic confinement in 1993, it has been improved by a factor of 3–4. In the mean time, organic materials, in particular intrinsically conducting polymers, had been considered as competitors of classical thermoelectrics, since their figure of merit has been improved several orders of magnitude in the last few years. We review here the evolution of the figure of merit or the power factor during the last years, and the best candidates to compete with inorganic materials. We also outline the best polymers to substitute classical thermoelectric materials and the advantages they present in comparison with inorganic systems. Full article
(This article belongs to the Special Issue New Energy Materials)
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Open AccessArticle Analysis of Pelletizing of Granulometric Separation Powder from Cork Industries
Materials 2014, 7(9), 6686-6700; https://doi.org/10.3390/ma7096686
Received: 25 July 2014 / Revised: 13 August 2014 / Accepted: 28 August 2014 / Published: 18 September 2014
Cited by 3 | PDF Full-text (3326 KB) | HTML Full-text | XML Full-text
Abstract
Cork industries generate a considerable amount of solid waste during their processing. Its management implies a problem for companies that should reconsider its reuse for other purposes. In this work, an analysis of pelletizing of granulometric separation powder, which is one of the
[...] Read more.
Cork industries generate a considerable amount of solid waste during their processing. Its management implies a problem for companies that should reconsider its reuse for other purposes. In this work, an analysis of pelletizing of granulometric separation powder, which is one of the major wastes in cork industries and which presents suitable properties (as an raw material) for its thermal use, is studied. However, its characteristic heterogeneity, along with its low bulk density (which makes its storage and transportation difficult) are restrictive factors for its energy use. Therefore, its densified form is a real alternative in order to make the product uniform and guarantee its proper use in boiler systems. Thus, the cork pellets (from granulometric separation powder) in the study met, except for ash content specification, the specifications in standard European Norm EN-Plus (B) for its application as fuel for domestic use. Full article
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Open AccessArticle Life Cycle Assessment for Proton Conducting Ceramics Synthesized by the Sol-Gel Process
Materials 2014, 7(9), 6677-6685; https://doi.org/10.3390/ma7096677
Received: 12 June 2014 / Revised: 3 September 2014 / Accepted: 8 September 2014 / Published: 16 September 2014
Cited by 1 | PDF Full-text (383 KB) | HTML Full-text | XML Full-text
Abstract
In this report, the environmental aspects of producing proton conducting ceramics are investigated by means of the environmental Life Cycle Assessment (LCA) method. The proton conducting ceramics BaZr0.8Y0.2O3-δ (BZY), BaCe0.9Y0.1O2.95 (BCY10), and Sr(Ce
[...] Read more.
In this report, the environmental aspects of producing proton conducting ceramics are investigated by means of the environmental Life Cycle Assessment (LCA) method. The proton conducting ceramics BaZr0.8Y0.2O3-δ (BZY), BaCe0.9Y0.1O2.95 (BCY10), and Sr(Ce0.9Zr0.1)0.95Yb0.05O3-δ (SCZY) were prepared by the sol-gel process. Their material requirements and environmental emissions were inventoried, and their energy requirements were determined, based on actual production data. This latter point makes the present LCA especially worthy of attention as a preliminary indication of future environmental impact. The analysis was performed according to the recommendations of ISO norms 14040 and obtained using the Gabi 6 software. The performance of the analyzed samples was also compared with each other. The LCA results for these proton conducting ceramics production processes indicated that the marine aquatic ecotoxicity potential (MAETP) made up the largest part, followed by fresh-water aquatic ecotoxicity potential (FAETP) and Human Toxicity Potential (HTP). The largest contribution was from energy consumption during annealing and calcinations steps. Full article
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Open AccessArticle Sustained Release of Lidocaine from Solvent-Free Biodegradable Poly[(d,l)-Lactide-co-Glycolide] (PLGA): In Vitro and In Vivo Study
Materials 2014, 7(9), 6660-6676; https://doi.org/10.3390/ma7096660
Received: 24 July 2014 / Revised: 19 August 2014 / Accepted: 9 September 2014 / Published: 16 September 2014
Cited by 4 | PDF Full-text (1906 KB) | HTML Full-text | XML Full-text
Abstract
Local anesthetics are commonly used for pain relief by regional nerve blocking. In this study, we fabricated solvent-free biodegradable pellets to extend the duration of lidocaine release without any significant local or systemic toxicity levels. To manufacture the pellets, poly[(d,l)-lactide-co-glycolide] (PLGA) was first
[...] Read more.
Local anesthetics are commonly used for pain relief by regional nerve blocking. In this study, we fabricated solvent-free biodegradable pellets to extend the duration of lidocaine release without any significant local or systemic toxicity levels. To manufacture the pellets, poly[(d,l)-lactide-co-glycolide] (PLGA) was first pre-mixed with lidocaine powder into different ratios. The powder mixture was then compressed with a mold (diameter of 1, 5, 8 or 10 mm) and sintered at 65 °C to form pellets. The in vitro release study showed that the lidocaine/PLGA pellets exhibited a tri-phase release behavior (a burst, a diffusion-controlled release and a degradation-dominated release) and reached completion around day 28. Scanning electron microscope (SEM) photos show that small channels could be found on the surfaces of the pellets on day 2. Furthermore, the polymer matrix swelled and fell apart on day 7, while the pellets became viscous after 10 days of in vitro elution. Perineural administration of the lidocaine/PLGA pellets produced anti-hypersensitivity effects lasting for at least 24 h in rats, significant when compared to the control group (a pure PLGA was pellet administered). In addition, no inflammation was detected within the nerve and in the neighboring muscle by histopathology. Full article
(This article belongs to the Section Biomaterials)
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