WorldWideScience

Sample records for sample encapsulation technology

  1. Performance evaluation soil samples utilizing encapsulation technology

    Science.gov (United States)

    Dahlgran, James R.

    1999-01-01

    Performance evaluation soil samples and method of their preparation using encapsulation technology to encapsulate analytes which are introduced into a soil matrix for analysis and evaluation by analytical laboratories. Target analytes are mixed in an appropriate solvent at predetermined concentrations. The mixture is emulsified in a solution of polymeric film forming material. The emulsified solution is polymerized to form microcapsules. The microcapsules are recovered, quantitated and introduced into a soil matrix in a predetermined ratio to form soil samples with the desired analyte concentration.

  2. Review of encapsulation technologies

    International Nuclear Information System (INIS)

    Shaulis, L.

    1996-09-01

    The use of encapsulation technology to produce a compliant waste form is an outgrowth from existing polymer industry technology and applications. During the past 12 years, the Department of Energy (DOE) has been researching the use of this technology to treat mixed wastes (i.e., containing hazardous and radioactive wastes). The two primary encapsulation techniques are microencapsulation and macroencapsulation. Microencapsulation is the thorough mixing of a binding agent with a powdered waste, such as incinerator ash. Macroencapsulation coats the surface of bulk wastes, such as lead debris. Cement, modified cement, and polyethylene are the binding agents which have been researched the most. Cement and modified cement have been the most commonly used binding agents to date. However, recent research conducted by DOE laboratories have shown that polyethylene is more durable and cost effective than cements. The compressive strength, leachability, resistance to chemical degradation, etc., of polyethylene is significantly greater than that of cement and modified cement. Because higher waste loads can be used with polyethylene encapsulant, the total cost of polyethylene encapsulation is significantly less costly than cement treatment. The only research lacking in the assessment of polyethylene encapsulation treatment for mixed wastes is pilot and full-scale testing with actual waste materials. To date, only simulated wastes have been tested. The Rocky Flats Environmental Technology Site had planned to conduct pilot studies using actual wastes during 1996. This experiment should provide similar results to the previous tests that used simulated wastes. If this hypothesis is validated as anticipated, it will be clear that polyethylene encapsulation should be pursued by DOE to produce compliant waste forms

  3. Polyethylene encapsulation full-scale technology demonstration. Final report

    International Nuclear Information System (INIS)

    Kalb, P.D.; Lageraaen, P.R.

    1994-10-01

    A full-scale integrated technology demonstration of a polyethylene encapsulation process, sponsored by the US Department of Energy (DOE) Office of Technology Development (OTD), was conducted at the Environmental ampersand Waste Technology Center at Brookhaven National Laboratory (BNL.) in September 1994. As part of the Polymer Solidification National Effort, polyethylene encapsulation has been developed and tested at BNL as an alternative solidification technology for improved, cost-effective treatment of low-level radioactive (LLW), hazardous and mixed wastes. A fully equipped production-scale system, capable of processing 900 kg/hr (2000 lb/hr), has been installed at BNL. The demonstration covered all facets of the integrated processing system including pre-treatment of aqueous wastes, precise feed metering, extrusion processing, on-line quality control monitoring, and process control

  4. Advances in encapsulation technologies for the management of mercury-contaminated hazardous wastes

    International Nuclear Information System (INIS)

    Randall, Paul; Chattopadhyay, Sandip

    2004-01-01

    Although industrial and commercial uses of mercury have been curtailed in recent times, there is a demonstrated need for the development of reliable hazardous waste management techniques because of historic operations that have led to significant contamination and ongoing hazardous waste generation. This study was performed to evaluate whether the U.S. EPA could propose treatment and disposal alternatives to the current land disposal restriction (LDR) treatment standards for mercury. The focus of this article is on the current state of encapsulation technologies that can be used to immobilize elemental mercury, mercury-contaminated debris, and other mercury-contaminated wastes, soils, sediments, or sludges. The range of encapsulation materials used in bench-scale, pilot-scale, and full-scale applications for mercury-contaminated wastes are summarized. Several studies have been completed regarding the application of sulfur polymer stabilization/solidification, chemically bonded phosphate ceramic encapsulation, and polyethylene encapsulation. Other materials reported in the literature as under development for encapsulation use include asphalt, polyester resins, synthetic elastomers, polysiloxane, sol-gels, Dolocrete TM , and carbon/cement mixtures. The primary objective of these encapsulation methods is to physically immobilize the wastes to prevent contact with leaching agents such as water. However, when used for mercury-contaminated wastes, several of these methods require a pretreatment or stabilization step to chemically fix mercury into a highly insoluble form prior to encapsulation. Performance data is summarized from the testing and evaluation of various encapsulated, mercury-contaminated wastes. Future technology development and research needs are also discussed

  5. Recent progress on thin-film encapsulation technologies for organic electronic devices

    Science.gov (United States)

    Yu, Duan; Yang, Yong-Qiang; Chen, Zheng; Tao, Ye; Liu, Yun-Fei

    2016-03-01

    Among the advanced electronic devices, flexible organic electronic devices with rapid development are the most promising technologies to customers and industries. Organic thin films accommodate low-cost fabrication and can exploit diverse molecules in inexpensive plastic light emitting diodes, plastic solar cells, and even plastic lasers. These properties may ultimately enable organic materials for practical applications in industry. However, the stability of organic electronic devices still remains a big challenge, because of the difficulty in fabricating commercial products with flexibility. These organic materials can be protected using substrates and barriers such as glass and metal; however, this results in a rigid device and does not satisfy the applications demanding flexible devices. Plastic substrates and transparent flexible encapsulation barriers are other possible alternatives; however, these offer little protection to oxygen and water, thus rapidly degrading the devices. Thin-film encapsulation (TFE) technology is most effective in preventing water vapor and oxygen permeation into the flexible devices. Because of these (and other) reasons, there has been an intense interest in developing transparent barrier materials with much lower permeabilities, and their market is expected to reach over 550 million by 2025. In this study, the degradation mechanism of organic electronic devices is reviewed. To increase the stability of devices in air, several TFE technologies were applied to provide efficient barrier performance. In this review, the degradation mechanism of organic electronic devices, permeation rate measurement, traditional encapsulation technologies, and TFE technologies are presented.

  6. Laboratory techniques for safe encapsulation of α-emitting powder samples

    International Nuclear Information System (INIS)

    Chamberlain, H.E.; Pottinger, J.S.

    1984-01-01

    Plutonium oxide powder samples can be encapsulated in thin plastic film to prevent spread of contamination in counting and X-ray diffraction equipment. The film has to be thin enough to transmit X-rays and α-particles. Techniques are described for the wrapping process and the precautions necessary to keep the sample processing line free of significant contamination. (author)

  7. Encapsulation by Janus spheroids

    OpenAIRE

    Li, Wei; Liu, Ya; Brett, Genevieve; Gunton, James D.

    2011-01-01

    The micro/nano encapsulation technology has acquired considerable attention in the fields of drug delivery, biomaterial engineering, and materials science. Based on recent advances in chemical particle synthesis, we propose a primitive model of an encapsulation system produced by the self-assembly of Janus oblate spheroids, particles with oblate spheroidal bodies and two hemi-surfaces coded with dissimilar chemical properties. Using Monte Carlo simulation, we investigate the encapsulation sys...

  8. Reverse micelle-loaded lipid nano-emulsions: new technology for nano-encapsulation of hydrophilic materials.

    Science.gov (United States)

    Anton, Nicolas; Mojzisova, Halina; Porcher, Emilien; Benoit, Jean-Pierre; Saulnier, Patrick

    2010-10-15

    This study presents novel, recently patented technology for encapsulating hydrophilic species in lipid nano-emulsions. The method is based on the phase-inversion temperature method (the so-called PIT method), which follows a low-energy and solvent-free process. The nano-emulsions formed are stable for months, and exhibit droplet sizes ranging from 10 to 200 nm. Hydrophilic model molecules of fluorescein sodium salt are encapsulated in the oily core of these nano-emulsion droplets through their solubilisation in the reverse micellar system. As a result, original, multi-scaled nano-objects are generated with a 'hydrophilic molecule in a reverse-micelles-in-oil-in-water' structure. Once fluorescein has been encapsulated it remains stable, for thermodynamic reasons, and the encapsulation yields can reach 90%. The reason why such complex objects can be formed is due to the soft method used (PIT method) which allows the conservation of the structure of the reverse micelles throughout the formulation process, up to their entrapment in the nano-emulsion droplets. In this study, we focus the investigation on the process itself, revealing its potential and limits. Since the formulation of nanocarriers for the encapsulation of hydrophilic substances still remains a challenge, this study may constitute a significant advance in this field. Copyright 2010 Elsevier B.V. All rights reserved.

  9. Technology of mammalian cell encapsulation

    NARCIS (Netherlands)

    Uludag, H; De Vos, P; Tresco, PA

    2000-01-01

    Entrapment of mammalian cells in physical membranes has been practiced since the early 1950s when it was originally introduced as a basic research tool. The method has since been developed based on the promise of its therapeutic usefulness in tissue transplantation. Encapsulation physically isolates

  10. Micro-Encapsulation of Probiotics

    Science.gov (United States)

    Meiners, Jean-Antoine

    Micro-encapsulation is defined as the technology for packaging with the help of protective membranes particles of finely ground solids, droplets of liquids or gaseous materials in small capsules that release their contents at controlled rates over prolonged periods of time under the influences of specific conditions (Boh, 2007). The material encapsulating the core is referred to as coating or shell.

  11. Integrating Micro- or Nanoscale Encapsulation Technology with Vitreous Cryopreservation: A New Strategy to Improve Biopreservation.

    Science.gov (United States)

    Zheng, Y Y; Zhao, G

      BACKGROUND: None-uniform distributions of temperatures, limited freezing and thawing rates, and thermal stresses are three main hindering factors for successful vitreous cryopreservation of mass volume of biosamples. Micro- and nanoscale encapsulation, owning the intrinsic features to avoid those limitations introduced by the traditional approaches, has been opened up a new way for effective and high-efficiency biopreservation. This short review article summarizes recent advances in cell encapsulation technology for biopreservation by manipulating cells and biological agents in micro- or nanoscale volume droplets and microgels, and discusses its promising applications for future vitreous cryopreservation.

  12. Encapsulated Islet Transplantation: Where Do We Stand?

    Science.gov (United States)

    Vaithilingam, Vijayaganapathy; Bal, Sumeet; Tuch, Bernard E

    2017-01-01

    Transplantation of pancreatic islets encapsulated within immuno-protective microcapsules is a strategy that has the potential to overcome graft rejection without the need for toxic immunosuppressive medication. However, despite promising preclinical studies, clinical trials using encapsulated islets have lacked long-term efficacy, and although generally considered clinically safe, have not been encouraging overall. One of the major factors limiting the long-term function of encapsulated islets is the host's immunological reaction to the transplanted graft which is often manifested as pericapsular fibrotic overgrowth (PFO). PFO forms a barrier on the capsule surface that prevents the ingress of oxygen and nutrients leading to islet cell starvation, hypoxia and death. The mechanism of PFO formation is still not elucidated fully and studies using a pig model have tried to understand the host immune response to empty alginate microcapsules. In this review, the varied strategies to overcome or reduce PFO are discussed, including alginate purification, altering microcapsule geometry, modifying alginate chemical composition, co-encapsulation with immunomodulatory cells, administration of pharmacological agents, and alternative transplantation sites. Nanoencapsulation technologies, such as conformal and layer-by-layer coating technologies, as well as nanofiber, thin-film nanoporous devices, and silicone based NanoGland devices are also addressed. Finally, this review outlines recent progress in imaging technologies to track encapsulated cells, as well as promising perspectives concerning the production of insulin-producing cells from stem cells for encapsulation.

  13. Different encapsulation strategies for implanted electronics

    Directory of Open Access Journals (Sweden)

    Winkler Sebastian

    2017-09-01

    Full Text Available Recent advancements in implant technology include increasing application of electronic systems in the human body. Hermetic encapsulation of electronic components is necessary, specific implant functions and body environments must be considered. Additional functions such as wireless communication systems require specialized technical solutions for the encapsulation.

  14. Perspective of metal encapsulation of waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-01-01

    A conceptual flow sheet is presented for encapsulating solid, stabilized calcine (e.g., supercalcine) in a solid lead alloy, using existing or developing technologies. Unresolved and potential problem areas of the flow sheet are outlined and suggestions are made as how metal encapsulation might be applied to other solid wastes from the fuel cycle. It is concluded that metal encapsulation is a technique applicable to many forms of solid wastes and is likely to meet future waste isolation criteria and regulations

  15. Encapsulation of nodal segments of lobelia chinensis

    Directory of Open Access Journals (Sweden)

    Weng Hing Thong

    2015-04-01

    Full Text Available Lobelia chinensis served as an important herb in traditional chinese medicine. It is rare in the field and infected by some pathogens. Therefore, encapsulation of axillary buds has been developed for in vitro propagation of L. chinensis. Nodal explants of L. chinensis were used as inclusion materials for encapsulation. Various combinations of calcium chloride and sodium alginate were tested. Encapsulation beads produced by mixing 50 mM calcium chloride and 3.5% sodium alginate supported the optimal in vitro conversion potential. The number of multiple shoots formed by encapsulated nodal segments was not significantly different from the average of shoots produced by non-encapsulated nodal segments. The encapsulated nodal segments regenerated in vitro on different medium. The optimal germination and regeneration medium was Murashige-Skoog medium. Plantlets regenerated from the encapsulated nodal segments were hardened, acclimatized and established well in the field, showing similar morphology with parent plants. This encapsulation technology would serve as an alternative in vitro regeneration system for L. chinensis.

  16. Acoustically excited encapsulated microbubbles and mitigation of biofouling

    KAUST Repository

    Qamar, Adnan

    2017-08-31

    Provided herein is a universally applicable biofouling mitigation technology using acoustically excited encapsulated microbubbles that disrupt biofilm or biofilm formation. For example, a method of reducing biofilm formation or removing biofilm in a membrane filtration system is provided in which a feed solution comprising encapsulated microbubbles is provided to the membrane under conditions that allow the encapsulated microbubbles to embed in a biofilm. Sonication of the embedded, encapsulated microbubbles disrupts the biofilm. Thus, provided herein is a membrane filtration system for performing the methods and encapsulated microbubbles specifically selected for binding to extracellular polymeric substances (EFS) in a biofilm.

  17. Considerations for successful transplantation of encapsulated pancreatic islets

    NARCIS (Netherlands)

    de Vos, P; Hamel, AF; Tatarkiewicz, K

    Encapsulation of pancreatic islets allows for transplantion in the absence of immunosuppression. The technology is based on the principle that transplanted tissue is protected for the host immune system by an artificial membrane. Encapsulation offers a solution to the shortage of donors in clinical

  18. Arsenic Encapsulation Using Portland Cement With Ferrous Sulfate/Lime And Terra-BondTM Technologies - Microcharacterization And Leaching Studies

    Science.gov (United States)

    This work reports the results of an investigation on the treatment and encapsulation of arsenic-containing materials by Portland cement with ferrous sulfate and lime (PFL) and Terra-BondTM, a commercially available patented technology. The arsenic materials treated we...

  19. Ensuring the Safety and Security of Frozen Lung Cancer Tissue Collections through the Encapsulation of Dried DNA

    Directory of Open Access Journals (Sweden)

    Kevin Washetine

    2018-06-01

    Full Text Available Collected specimens for research purposes may or may not be made available depending on their scarcity and/or on the project needs. Their protection against degradation or in the event of an incident is pivotal. Duplication and storage on a different site is the best way to assure their sustainability. The conservation of samples at room temperature (RT by duplication can facilitate their protection. We describe a security system for the collection of non-small cell lung cancers (NSCLC stored in the biobank of the Nice Hospital Center, France, by duplication and conservation of lyophilized (dried, encapsulated DNA kept at RT. Therefore, three frozen tissue collections from non-smoking, early stage and sarcomatoid carcinoma NSCLC patients were selected for this study. DNA was extracted, lyophilized and encapsulated at RT under anoxic conditions using the DNAshell technology. In total, 1974 samples from 987 patients were encapsulated. Six and two capsules from each sample were stored in the biobanks of the Nice and Grenoble (France Hospitals, respectively. In conclusion, DNA maintained at RT allows for the conservation, duplication and durability of collections of interest stored in biobanks. This is a low-cost and safe technology that requires a limited amount of space and has a low environmental impact.

  20. Ensuring the Safety and Security of Frozen Lung Cancer Tissue Collections through the Encapsulation of Dried DNA.

    Science.gov (United States)

    Washetine, Kevin; Kara-Borni, Mehdi; Heeke, Simon; Bonnetaud, Christelle; Félix, Jean-Marc; Ribeyre, Lydia; Bence, Coraline; Ilié, Marius; Bordone, Olivier; Pedro, Marine; Maitre, Priscilla; Tanga, Virginie; Gormally, Emmanuelle; Mossuz, Pascal; Lorimier, Philippe; Marquette, Charles Hugo; Mouroux, Jérôme; Cohen, Charlotte; Lassalle, Sandra; Long-Mira, Elodie; Clément, Bruno; Dagher, Georges; Hofman, Véronique; Hofman, Paul

    2018-06-11

    Collected specimens for research purposes may or may not be made available depending on their scarcity and/or on the project needs. Their protection against degradation or in the event of an incident is pivotal. Duplication and storage on a different site is the best way to assure their sustainability. The conservation of samples at room temperature (RT) by duplication can facilitate their protection. We describe a security system for the collection of non-small cell lung cancers (NSCLC) stored in the biobank of the Nice Hospital Center, France, by duplication and conservation of lyophilized (dried), encapsulated DNA kept at RT. Therefore, three frozen tissue collections from non-smoking, early stage and sarcomatoid carcinoma NSCLC patients were selected for this study. DNA was extracted, lyophilized and encapsulated at RT under anoxic conditions using the DNAshell technology. In total, 1974 samples from 987 patients were encapsulated. Six and two capsules from each sample were stored in the biobanks of the Nice and Grenoble (France) Hospitals, respectively. In conclusion, DNA maintained at RT allows for the conservation, duplication and durability of collections of interest stored in biobanks. This is a low-cost and safe technology that requires a limited amount of space and has a low environmental impact.

  1. Photovoltaic module encapsulation design and materials selection, volume 1

    Science.gov (United States)

    Cuddihy, E.; Carroll, W.; Coulbert, C.; Gupta, A.; Liang, R. H.

    1982-01-01

    Encapsulation material system requirements, material selection criteria, and the status and properties of encapsulation materials and processes available are presented. Technical and economic goals established for photovoltaic modules and encapsulation systems and their status are described. Available encapsulation technology and data are presented to facilitate design and material selection for silicon flat plate photovoltaic modules, using the best materials available and processes optimized for specific power applications and geographic sites. The operational and environmental loads that encapsulation system functional requirements and candidate design concepts and materials that are identified to have the best potential to meet the cost and performance goals for the flat plate solar array project are described. Available data on encapsulant material properties, fabrication processing, and module life and durability characteristics are presented.

  2. Radioactive Waste Conditioning, Immobilisation, And Encapsulation Processes And Technologies: Overview And Advances (Chapter 7)

    Energy Technology Data Exchange (ETDEWEB)

    Jantzen, Carol M. [Savannah River National Lab., Aiken SC (United States); Lee, William E. [Imperial College, London (United Kingdom). Dept. of Materials; Ojovan, Michael I. [Univ. of Sheffield (United Kingdom). Dept. of Materials Science and Engineering

    2012-10-19

    The main immobilization technologies that are available commercially and have been demonstrated to be viable are cementation, bituminization, and vitrification. Vitrification is currently the most widely used technology for the treatment of high level radioactive wastes (HLW) throughout the world. Most of the nations that have generated HLW are immobilizing in either alkali borosilicate glass or alkali aluminophosphate glass. The exact compositions of nuclear waste glasses are tailored for easy preparation and melting, avoidance of glass-in-glass phase separation, avoidance of uncontrolled crystallization, and acceptable chemical durability, e.g., leach resistance. Glass has also been used to stabilize a variety of low level wastes (LLW) and mixed (radioactive and hazardous) low level wastes (MLLW) from other sources such as fuel rod cladding/decladding processes, chemical separations, radioactive sources, radioactive mill tailings, contaminated soils, medical research applications, and other commercial processes. The sources of radioactive waste generation are captured in other chapters in this book regarding the individual practices in various countries (legacy wastes, currently generated wastes, and future waste generation). Future waste generation is primarily driven by interest in sources of clean energy and this has led to an increased interest in advanced nuclear power production. The development of advanced wasteforms is a necessary component of the new nuclear power plant (NPP) flowsheets. Therefore, advanced nuclear wasteforms are being designed for robust disposal strategies. A brief summary is given of existing and advanced wasteforms: glass, glass-ceramics, glass composite materials (GCM’s), and crystalline ceramic (mineral) wasteforms that chemically incorporate radionuclides and hazardous species atomically in their structure. Cementitious, geopolymer, bitumen, and other encapsulant wasteforms and composites that atomically bond and encapsulate

  3. Lead macro-encapsulation conceptual and experimental studies

    International Nuclear Information System (INIS)

    Orebaugh, E.G.

    1993-01-01

    Macro-encapsulation, the regulatory treatment for radioactively contaminated lead (mixed) waste has been conceptually and experimentally evaluated for practical application. Epoxy encapsulants molded around lead billets have proven to be exceptionally rugged, easily applied, have high radiation and chemical stability, and minimize required process equipment and production of secondary wastes. This technology can now be considered developed, and can be applied as discussed in this report

  4. Review of potential processing techniques for the encapsulation of wastes in thermoplastic polymers

    International Nuclear Information System (INIS)

    Patel, B.R.; Lageraaen, P.R.; Kalb, P.D.

    1995-08-01

    Thermoplastic encapsulation has been extensively studied at Brookhaven National Laboratory's (BNL) Environmental and Waste Technology Center (EWTC) as a waste encapsulation technology applicable to a wide range of waste types including radioactive, hazardous and mixed wastes. Encapsulation involves processing thermoplastic and waste materials into a waste form product by heating and mixing both materials into a homogeneous molten mixture. Cooling of the melt results in a solid monolithic waste form in which contaminants have been completely surrounded by a polymer matrix. Heating and mixing requirements for successful waste encapsulation can be met using proven technologies available in various types of commercial equipment. Processing techniques for thermoplastic materials, such as low density polyethylene (LDPE), are well established within the plastics industry. The majority of commercial polymer processing is accomplished using extruders, mixers or a combination of these technologies. Extruders and mixers are available in a broad range of designs and are used during the manufacture of consumer and commercial products as well as for compounding applications. Compounding which refers to mixing additives such as stabilizers and/or colorants with polymers, is analogous to thermoplastic encapsulation. Several processing technologies were investigated for their potential application in encapsulating residual sorbent waste in selected thermoplastic polymers, including single-screw extruders, twin-screw extruders, continuous mixers, batch mixers as well as other less conventional devices. Each was evaluated based on operational ease, quality control, waste handling capabilities as well as degree of waste pretreatment required. Based on literature review, this report provides a description of polymer processing technologies, a discussion of the merits and limitations of each and an evaluation of their applicability to the encapsulation of sorbent wastes

  5. Review of potential processing techniques for the encapsulation of wastes in thermoplastic polymers

    Energy Technology Data Exchange (ETDEWEB)

    Patel, B.R.; Lageraaen, P.R.; Kalb, P.D.

    1995-08-01

    Thermoplastic encapsulation has been extensively studied at Brookhaven National Laboratory`s (BNL) Environmental and Waste Technology Center (EWTC) as a waste encapsulation technology applicable to a wide range of waste types including radioactive, hazardous and mixed wastes. Encapsulation involves processing thermoplastic and waste materials into a waste form product by heating and mixing both materials into a homogeneous molten mixture. Cooling of the melt results in a solid monolithic waste form in which contaminants have been completely surrounded by a polymer matrix. Heating and mixing requirements for successful waste encapsulation can be met using proven technologies available in various types of commercial equipment. Processing techniques for thermoplastic materials, such as low density polyethylene (LDPE), are well established within the plastics industry. The majority of commercial polymer processing is accomplished using extruders, mixers or a combination of these technologies. Extruders and mixers are available in a broad range of designs and are used during the manufacture of consumer and commercial products as well as for compounding applications. Compounding which refers to mixing additives such as stabilizers and/or colorants with polymers, is analogous to thermoplastic encapsulation. Several processing technologies were investigated for their potential application in encapsulating residual sorbent waste in selected thermoplastic polymers, including single-screw extruders, twin-screw extruders, continuous mixers, batch mixers as well as other less conventional devices. Each was evaluated based on operational ease, quality control, waste handling capabilities as well as degree of waste pretreatment required. Based on literature review, this report provides a description of polymer processing technologies, a discussion of the merits and limitations of each and an evaluation of their applicability to the encapsulation of sorbent wastes.

  6. A chemically stable PVD multilayer encapsulation for lithium microbatteries

    International Nuclear Information System (INIS)

    Ribeiro, J F; Sousa, R; Cunha, D J; Vieira, E M F; Goncalves, L M; Silva, M M; Dupont, L

    2015-01-01

    A multilayer physical vapour deposition (PVD) thin-film encapsulation method for lithium microbatteries is presented. Lithium microbatteries with a lithium cobalt oxide (LiCoO 2 ) cathode, a lithium phosphorous oxynitride (LiPON) electrolyte and a metallic lithium anode are under development, using PVD deposition techniques. Metallic lithium film is still the most common anode on this battery technology; however, it presents a huge challenge in terms of material encapsulation (lithium reacts with almost any materials deposited on top and almost instantly begins oxidizing in contact with atmosphere). To prove the encapsulation concept and perform all the experiments, lithium films were deposited by thermal evaporation technique on top of a glass substrate, with previously patterned Al/Ti contacts. Three distinct materials, in a multilayer combination, were tested to prevent lithium from reacting with protection materials and atmosphere. These multilayer films were deposited by RF sputtering and were composed of lithium phosphorous oxide (LiPO), LiPON and silicon nitride (Si 3 N 4 ). To complete the long-term encapsulation after breaking the vacuum, an epoxy was applied on top of the PVD multilayer. In order to evaluate oxidation state of lithium films, the lithium resistance was measured in a four probe setup (cancelling wires/contact resistances) and resistivity calculated, considering physical dimensions. A lithium resistivity of 0.16 Ω μm was maintained for more than a week. This PVD multilayer exonerates the use of chemical vapour deposition (CVD), glove-box chambers and sample manipulation between them, significantly reducing the fabrication cost, since battery and its encapsulation are fabricated in the same PVD chamber. (paper)

  7. A chemically stable PVD multilayer encapsulation for lithium microbatteries

    Science.gov (United States)

    Ribeiro, J. F.; Sousa, R.; Cunha, D. J.; Vieira, E. M. F.; Silva, M. M.; Dupont, L.; Goncalves, L. M.

    2015-10-01

    A multilayer physical vapour deposition (PVD) thin-film encapsulation method for lithium microbatteries is presented. Lithium microbatteries with a lithium cobalt oxide (LiCoO2) cathode, a lithium phosphorous oxynitride (LiPON) electrolyte and a metallic lithium anode are under development, using PVD deposition techniques. Metallic lithium film is still the most common anode on this battery technology; however, it presents a huge challenge in terms of material encapsulation (lithium reacts with almost any materials deposited on top and almost instantly begins oxidizing in contact with atmosphere). To prove the encapsulation concept and perform all the experiments, lithium films were deposited by thermal evaporation technique on top of a glass substrate, with previously patterned Al/Ti contacts. Three distinct materials, in a multilayer combination, were tested to prevent lithium from reacting with protection materials and atmosphere. These multilayer films were deposited by RF sputtering and were composed of lithium phosphorous oxide (LiPO), LiPON and silicon nitride (Si3N4). To complete the long-term encapsulation after breaking the vacuum, an epoxy was applied on top of the PVD multilayer. In order to evaluate oxidation state of lithium films, the lithium resistance was measured in a four probe setup (cancelling wires/contact resistances) and resistivity calculated, considering physical dimensions. A lithium resistivity of 0.16 Ω μm was maintained for more than a week. This PVD multilayer exonerates the use of chemical vapour deposition (CVD), glove-box chambers and sample manipulation between them, significantly reducing the fabrication cost, since battery and its encapsulation are fabricated in the same PVD chamber.

  8. Suppression of intrinsic roughness in encapsulated graphene

    DEFF Research Database (Denmark)

    Thomsen, Joachim Dahl; Gunst, Tue; Gregersen, Søren Schou

    2017-01-01

    Roughness in graphene is known to contribute to scattering effects which lower carrier mobility. Encapsulating graphene in hexagonal boron nitride (hBN) leads to a significant reduction in roughness and has become the de facto standard method for producing high-quality graphene devices. We have...... fabricated graphene samples encapsulated by hBN that are suspended over apertures in a substrate and used noncontact electron diffraction measurements in a transmission electron microscope to measure the roughness of encapsulated graphene inside such structures. We furthermore compare the roughness...... of these samples to suspended bare graphene and suspended graphene on hBN. The suspended heterostructures display a root mean square (rms) roughness down to 12 pm, considerably less than that previously reported for both suspended graphene and graphene on any substrate and identical within experimental error...

  9. Encapsulation Efficiency, Oscillatory Rheometry

    Directory of Open Access Journals (Sweden)

    Z. Mohammad Hassani

    2014-01-01

    Full Text Available Nanoliposomes are one of the most important polar lipid-based nanocarriers which can be used for encapsulation of both hydrophilic and hydrophobic active compounds. In this research, nanoliposomes based on lecithin-polyethylene glycol-gamma oryzanol were prepared by using a modified thermal method. Only one melting peak in DSC curve of gamma oryzanol bearing liposomes was observed which could be attributed to co-crystallization of both compounds. The addition of gamma oryzanol, caused to reduce the melting point of 5% (w/v lecithin-based liposome from 207°C to 163.2°C. At high level of lecithin, increasing of liposome particle size (storage at 4°C for two months was more obvious and particle size increased from 61 and 113 to 283 and 384 nanometers, respectively. The encapsulation efficiency of gamma oryzanol increased from 60% to 84.3% with increasing lecithin content. The encapsulation stability of oryzanol in liposome was determined at different concentrations of lecithin 3, 5, 10, 20% (w/v and different storage times (1, 7, 30 and 60 days. In all concentrations, the encapsulation stability slightly decreased during 30 days storage. The scanning electron microscopy (SEM images showed relatively spherical to elliptic particles which indicated to low extent of particles coalescence. The oscillatory rheometry showed that the loss modulus of liposomes were higher than storage modulus and more liquid-like behavior than solid-like behavior. The samples storage at 25°C for one month, showed higher viscoelastic parameters than those having been stored at 4°C which were attributed to higher membrane fluidity at 25°C and their final coalescence.Nanoliposomes are one of the most important polar lipid based nanocarriers which can be used for encapsulation of both hydrophilic and hydrophobic active compounds. In this research, nanoliposomes based on lecithin-polyethylene glycol-gamma oryzanol were prepared by using modified thermal method. Only one

  10. Comparisons of alternative sites for the encapsulation plant

    International Nuclear Information System (INIS)

    Havel, R.

    2000-12-01

    This report discuses the pros and cons of localizing the spent fuel encapsulation plant at the planned Swedish repository for spent nuclear fuel or at CLAB (Central interim storage facility for spent nuclear fuel). After weighing together all aspects (economy, technology, safety, transports, personnel and environment) it is concluded that building the encapsulation plant in direct connection to CLAB is the most advantageous alternative

  11. Flat-plate solar array project. Volume 7: Module encapsulation

    Science.gov (United States)

    Cuddihy, E.; Coulbert, C.; Gupta, A.; Liang, R.

    1986-01-01

    The objective of the Encapsulation Task was to develop, demonstrate, and qualify photovoltaic (PV) module encapsulation systems that would provide 20 year (later decreased to 30 year) life expectancies in terrestrial environments, and which would be compatible with the cost and performance goals of the Flat-Plate Solar Array (FSA) Project. The scope of the Encapsulation Task included the identification, development, and evaluation of material systems and configurations required to support and protect the optically and electrically active solar cell circuit components in the PV module operating environment. Encapsulation material technologies summarized include the development of low cost ultraviolet protection techniques, stable low cost pottants, soiling resistant coatings, electrical isolation criteria, processes for optimum interface bonding, and analytical and experimental tools for evaluating the long term durability and structural adequacy of encapsulated modules. Field testing, accelerated stress testing, and design studies have demonstrated that encapsulation materials, processes, and configurations are available that meet the FSA cost and performance goals.

  12. Limonene encapsulation in freeze dried gellan systems.

    Science.gov (United States)

    Evageliou, Vasiliki; Saliari, Dimitra

    2017-05-15

    The encapsulation of limonene in freeze-dried gellan systems was investigated. Surface and encapsulated limonene content was determined by measurement of the absorbance at 252nm. Gellan matrices were both gels and solutions. For a standard gellan concentration (0.5wt%) gelation was induced by potassium or calcium chloride. Furthermore, gellan solutions of varying concentrations (0.25-1wt%) were also studied. Limonene was added at two different concentrations (1 and 2mL/100g sample). Gellan gels encapsulated greater amounts of limonene than solutions. Among all gellan gels, the KCl gels had the greater encapsulated limonene content. However, when the concentration of limonene was doubled in these KCl gels, the encapsulated limonene decreased. The surface limonene content was significant, especially for gellan solutions. The experimental conditions and not the mechanical properties of the matrices were the dominant factor in the interpretation of the observed results. Copyright © 2016 Elsevier Ltd. All rights reserved.

  13. Properties of probiotics and encapsulated probiotics in food.

    Science.gov (United States)

    Ozyurt, V Hazal; Ötles, Semih

    2014-01-01

    Probiotics are microorganisms which confer health benefits upon application in sufficiently-high viable cell amounts. Probiotics are typically members of Lactobacillus and Bifidobacterium species commonly associated with human gastrointestinal tracts. In the recent past, there has been a rising interest in producing functional foods containing encapsulated probiotic bacteria. Recent studies have been reported using dairy products like cheese, yogurt and ice cream as food carrier, and non-dairy products like meat, fruits, cereals, chocolate, etc. However, the industrial sector contains only few encapsulated probiotic products. Probiotics have been developed by several companies in a capsule or a tablet form. The review compiles probiotics, encapsulation technology and cell life in the food matrices.

  14. Novel encapsulation systems and processes for overcoming the challenges of polypharmacy.

    Science.gov (United States)

    Orlu-Gul, Mine; Topcu, Ahmet Alptekin; Shams, Talayeh; Mahalingam, Suntharavathanan; Edirisinghe, Mohan

    2014-10-01

    The encapsulation process has been studied to develop smart drug delivery systems for decades. In particular, micro-encapsulation and nano-encapsulation approaches have gained wide interest in the development of particulate drug delivery and achieved progress in specialties such as nano-medicine. Encapsulation technologies have evolved through various platforms including emulsion solvent evaporation, spray drying and polymer conjugation. Among current encapsulation methods, electrohydrodynamic and microfluidic processes stand out by enabling the making of formulations with uniform shape and nanoscale size. Pressurized gyration is a new method of combining rotation and controlled pressure to produce encapsulated structures of various morphologies. In this review we address key developments in electrohydrodynamic, microfluidic, their combined and new approaches as well as their potential to obtain combined therapies with desired drug release profiles. Copyright © 2014 Elsevier Ltd. All rights reserved.

  15. Polycaprolactone Thin-Film Micro- and Nanoporous Cell-Encapsulation Devices.

    Science.gov (United States)

    Nyitray, Crystal E; Chang, Ryan; Faleo, Gaetano; Lance, Kevin D; Bernards, Daniel A; Tang, Qizhi; Desai, Tejal A

    2015-06-23

    Cell-encapsulating devices can play an important role in advancing the types of tissue available for transplantation and further improving transplant success rates. To have an effective device, encapsulated cells must remain viable, respond to external stimulus, and be protected from immune responses, and the device itself must elicit a minimal foreign body response. To address these challenges, we developed a micro- and a nanoporous thin-film cell encapsulation device from polycaprolactone (PCL), a material previously used in FDA-approved biomedical devices. The thin-film device construct allows long-term bioluminescent transfer imaging, which can be used for monitoring cell viability and device tracking. The ability to tune the microporous and nanoporous membrane allows selective protection from immune cell invasion and cytokine-mediated cell death in vitro, all while maintaining typical cell function, as demonstrated by encapsulated cells' insulin production in response to glucose stimulation. To demonstrate the ability to track, visualize, and monitor the viability of cells encapsulated in implanted thin-film devices, we encapsulated and implanted luciferase-positive MIN6 cells in allogeneic mouse models for up to 90 days. Lack of foreign body response in combination with rapid neovascularization around the device shows promise in using this technology for cell encapsulation. These devices can help elucidate the metrics required for cell encapsulation success and direct future immune-isolation therapies.

  16. Elastin-like polypeptides: the power of design for smart cell encapsulation.

    Science.gov (United States)

    Bandiera, Antonella

    2017-01-01

    Cell encapsulation technology is still a challenging issue. Innovative methodologies such as additive manufacturing, and alternative bioprocesses, such as cell therapeutic delivery, where cell encapsulation is a key tool are rapidly gaining importance for their potential in regenerative medicine. Responsive materials such as elastin-based recombinant expression products have features that are particularly attractive for cell encapsulation. They can be designed and tailored to meet desired requirements. Thus, they represent promising candidates for the development of new concept-based materials that can be employed in this field. Areas covered: An overview of the design and employment of elastin-like polypeptides for cell encapsulation is given to outline the state of the art. Special attention is paid to the design of the macromolecule employed as well as to the method of matrix formation and the biological system involved. Expert opinion: As a result of recent progress in regenerative medicine there is a compelling need for materials that provide specific properties and demonstrate defined functional features. Rationally designed materials that may adapt according to applied external stimuli and that are responsive to biological systems, such as elastin-like polypeptides, belong to this class of smart material. A run through the components described to date represents a good starting point for further advancement in this area. Employment of these components in cell encapsulation application will promote its advance toward 'smart cell encapsulation technology'.

  17. Encapsulation of health-promoting ingredients: applications in foodstuffs.

    Science.gov (United States)

    Tolve, Roberta; Galgano, Fernanda; Caruso, Marisa Carmela; Tchuenbou-Magaia, Fideline Laure; Condelli, Nicola; Favati, Fabio; Zhang, Zhibing

    2016-12-01

    Many nutritional experts and food scientists are interested in developing functional foods containing bioactive agents and many of these health-promoting ingredients may benefit from nano/micro-encapsulation technology. Encapsulation has been proven useful to improve the physical and the chemical stability of bioactive agents, as well as their bioavailability and efficacy, enabling their incorporation into a wide range of formulations aimed to functional food production. There are several reviews concerning nano/micro-encapsulation techniques, but none are focused on the incorporation of the bioactive agents into food matrices. The aim of this paper was to investigate the development of microencapsulated food, taking into account the different bioactive ingredients, the variety of processes, techniques and coating materials that can be used for this purpose.

  18. Treatment of Diabetes with Encapsulated Islets

    NARCIS (Netherlands)

    de Vos, Paul; Spasojevic, Milica; Faas, Marijke M.; Pedraz, JL; Orive, G

    2010-01-01

    Cell encapsulation has been proposed for the treatment of a wide variety of diseases since it allows for transplantation of cells in the absence of undesired immunosuppression. The technology has been proposed to be a solution for the treatment of diabetes since it potentially allows a mandatory

  19. Encapsulation layer design and scalability in encapsulated vertical 3D RRAM

    International Nuclear Information System (INIS)

    Yu, Muxi; Fang, Yichen; Wang, Zongwei; Chen, Gong; Pan, Yue; Yang, Xue; Yin, Minghui; Yang, Yuchao; Li, Ming; Cai, Yimao; Huang, Ru

    2016-01-01

    Here we propose a novel encapsulated vertical 3D RRAM structure with each resistive switching cell encapsulated by dielectric layers, contributing to both the reliability improvement of individual cells and thermal disturbance reduction of adjacent cells due to the effective suppression of unwanted oxygen vacancy diffusion. In contrast to the traditional vertical 3D RRAM, encapsulated bar-electrodes are adopted in the proposed structure substituting the previous plane-electrodes, thus encapsulated resistive switching cells can be naturally formed by simply oxidizing the tip of the metal bar-electrodes. In this work, TaO x -based 3D RRAM devices with SiO 2 and Si 3 N 4 as encapsulation layers are demonstrated, both showing significant advantages over traditional unencapsulated vertical 3D RRAM. Furthermore, it was found thermal conductivity and oxygen blocking ability are two key parameters of the encapsulation layer design influencing the scalability of vertical 3D RRAM. Experimental and simulation data show that oxygen blocking ability is more critical for encapsulation layers in the relatively large scale, while thermal conductivity becomes dominant as the stacking layers scale to the sub-10 nm regime. Finally, based on the notable impacts of the encapsulation layer on 3D RRAM scaling, an encapsulation material with both excellent oxygen blocking ability and high thermal conductivity such as AlN is suggested to be highly desirable to maximize the advantages of the proposed encapsulated structure. The findings in this work could pave the way for reliable ultrahigh-density storage applications in the big data era. (paper)

  20. Acoustically excited encapsulated microbubbles and mitigation of biofouling

    KAUST Repository

    Qamar, Adnan; Fortunato, Luca; Leiknes, TorOve

    2017-01-01

    Provided herein is a universally applicable biofouling mitigation technology using acoustically excited encapsulated microbubbles that disrupt biofilm or biofilm formation. For example, a method of reducing biofilm formation or removing biofilm in a

  1. Improving gas sensor properties of encapsulated ZnO nanorods for ethanol detection using ZnO:Cr layer as an encapsulated layer

    Directory of Open Access Journals (Sweden)

    S. Safa

    2017-11-01

    Full Text Available In this study, encapsulated ZnO nanorods with different amount of chromium (Cr dopant (0-4.5 at.% were prepared with hydrothermal method, and their sensitivities as gas sensors against ethanol vapor were investigated. Morphologies of samples were explored by field emission scanning electron microscope (FESEM which showed that encapsulation process increased the diameter of ZnO nanorods. Existence of Cr in ZnO nanorods structures was confirmed by Energy-dispersive X-ray spectroscopy (EDX. Based on X-ray diffraction (XRD analysis, the ZnO:Cr nanorods had wurtzite crystal structure, and adding Cr did not alter the crystal structure of ZnO. Electrical measurements revealed that current levels of samples were decreased by adding Cr, while the current level of the sample with 4.5 at.% was increased. This reduction could be attributed to the presence of Cr3+ ions, which led to decrease of charge carriers. Besides, due to the catalytic properties of Cr and its lower ionization energy than Zn, it was observed that Cr dopant improved the detection sensitivity of samples, and decreased the optimum operating temperature of samples. Among all samples, the most sensitivity (14 was obtained based on the sample with 1.5 at.% of Cr for 500 ppm ethanol vapor at the optimum temperature (250 . In fact, by encapsulating the samples, they became rougher, so the appropriate places to absorb and decompose of gas molecules are increased.

  2. Evaluation of Encapsulated Inhibitor for Autonomous Corrosion Protection

    Science.gov (United States)

    Johnsey, M. N.; Li, W.; Buhrow, J. W.; Calle, L. M.; Pearman, B. P.; Zhang, X.

    2015-01-01

    This work concerns the development of smart coating technologies based on microencapsulation for the autonomous control of corrosion. Microencapsulation allows the incorporation of corrosion inhibitors into coating which provides protection through corrosion-controlled release of these inhibitors.One critical aspect of a corrosion protective smart coating is the selection of corrosion inhibitor for encapsulation and comparison of the inhibitor function before and after encapsulation. For this purpose, a systematic approach is being used to evaluate free and encapsulated corrosion inhibitors by salt immersion. Visual, optical microscope, and Scanning Electron Microscope (with low-angle backscatter electron detector) are used to evaluate these inhibitors. It has been found that the combination of different characterization tools provide an effective method for evaluation of early stage localized corrosion and the effectiveness of corrosion inhibitors.

  3. High throughput single-cell and multiple-cell micro-encapsulation.

    Science.gov (United States)

    Lagus, Todd P; Edd, Jon F

    2012-06-15

    Microfluidic encapsulation methods have been previously utilized to capture cells in picoliter-scale aqueous, monodisperse drops, providing confinement from a bulk fluid environment with applications in high throughput screening, cytometry, and mass spectrometry. We describe a method to not only encapsulate single cells, but to repeatedly capture a set number of cells (here we demonstrate one- and two-cell encapsulation) to study both isolation and the interactions between cells in groups of controlled sizes. By combining drop generation techniques with cell and particle ordering, we demonstrate controlled encapsulation of cell-sized particles for efficient, continuous encapsulation. Using an aqueous particle suspension and immiscible fluorocarbon oil, we generate aqueous drops in oil with a flow focusing nozzle. The aqueous flow rate is sufficiently high to create ordering of particles which reach the nozzle at integer multiple frequencies of the drop generation frequency, encapsulating a controlled number of cells in each drop. For representative results, 9.9 μm polystyrene particles are used as cell surrogates. This study shows a single-particle encapsulation efficiency P(k=1) of 83.7% and a double-particle encapsulation efficiency P(k=2) of 79.5% as compared to their respective Poisson efficiencies of 39.3% and 33.3%, respectively. The effect of consistent cell and particle concentration is demonstrated to be of major importance for efficient encapsulation, and dripping to jetting transitions are also addressed. Continuous media aqueous cell suspensions share a common fluid environment which allows cells to interact in parallel and also homogenizes the effects of specific cells in measurements from the media. High-throughput encapsulation of cells into picoliter-scale drops confines the samples to protect drops from cross-contamination, enable a measure of cellular diversity within samples, prevent dilution of reagents and expressed biomarkers, and amplify

  4. Hydrogels for in situ encapsulation of biomimetic membrane arrays

    DEFF Research Database (Denmark)

    Ibragimova, Sania; Jensen, Karin Bagger Stibius; Szewczykowski, Piotr Przemyslaw

    2012-01-01

    to chemically initiated hydrogels; however, for all hydrogels the permeability was several-fold higher than the water permeability of conventional reverse osmosis (RO) membranes. Lifetimes of freestanding BLM arrays in gel precursor solutions were short compared to arrays formed in buffer. However, polymerizing......Hydrogels are hydrophilic, porous polymer networks that can absorb up to thousands of times their own weight in water. They have many potential applications, one of which is the encapsulation of freestanding black lipid membranes (BLMs) for novel separation technologies or biosensor applications....... We investigated gels for in situ encapsulation of multiple BLMs formed across apertures in a hydrophobic ethylene tetrafluoroethylene (ETFE) support. The encapsulation gels consisted of networks of poly(ethylene glycol)-dimethacrylate or poly(ethylene glycol)-diacrylate polymerized using either...

  5. Effectiveness of amorphous silica encapsulation technology on welding fume particles and its impact on mechanical properties of welds

    International Nuclear Information System (INIS)

    Wang, Jun; Wu, Chang-Yu; Franke, Gene

    2014-01-01

    Highlights: • A novel welding shielding gas containing a silica precursor. • Up to 76% of the welding fume particles encapsulated in an amorphous silica layer. • No statistical difference between different types of welds in mechanical tests. • Can potentially reduce the toxicity of welding fume particles. - Abstract: Stainless steel welding generates nano-sized fume particles containing toxic metals which may cause serious health effects upon inhalation. The objective of this study was to investigate the effectiveness of an amorphous silica encapsulation (ASE) technology by evaluating its silica coating efficiency (SCE), particle morphology, and its impact on the weld’s mechanical properties. Tetramethylsilane (TMS) added to the welding shielding gas decomposed at the high-temperature arc zone to enable the silica coating. Collected welding fume particles were digested by two acid mixtures with different degrees of silica solubility, and the measured mass differences in the digests were used to determine the SCE. The SCEs were around 48–64% at the low and medium primary shielding gas flow rates. The highest SCE of 76% occurred at the high shielding gas flow rate (30 Lpm) with a TMS carrier gas flow of 0.64 Lpm. Transmission electron microscopy (TEM) images confirmed the amorphous silica layer on the welding fume particles at most gas flow rates, as well as abundant stand-alone silica particles formed at the high gas flow rate. Metallography showed that welds from the baseline and from the ASE technology were similar except for a tiny crack found in one particular weld made with the ASE technology. Tensile tests showed no statistical difference between the baseline and the ASE welds. All the above test results confirm that welding equipment retrofitted with the ASE technology has the potential to effectively address the toxicity problem of welding fume particles without affecting the mechanical properties of the welds

  6. On-chip Magnetic Separation and Cell Encapsulation in Droplets

    Science.gov (United States)

    Chen, A.; Byvank, T.; Bharde, A.; Miller, B. L.; Chalmers, J. J.; Sooryakumar, R.; Chang, W.-J.; Bashir, R.

    2012-02-01

    The demand for high-throughput single cell assays is gaining importance because of the heterogeneity of many cell suspensions, even after significant initial sorting. These suspensions may display cell-to-cell variability at the gene expression level that could impact single cell functional genomics, cancer, stem-cell research and drug screening. The on-chip monitoring of individual cells in an isolated environment could prevent cross-contamination, provide high recovery yield and ability to study biological traits at a single cell level These advantages of on-chip biological experiments contrast to conventional methods, which require bulk samples that provide only averaged information on cell metabolism. We report on a device that integrates microfluidic technology with a magnetic tweezers array to combine the functionality of separation and encapsulation of objects such as immunomagnetically labeled cells or magnetic beads into pico-liter droplets on the same chip. The ability to control the separation throughput that is independent of the hydrodynamic droplet generation rate allows the encapsulation efficiency to be optimized. The device can potentially be integrated with on-chip labeling and/or bio-detection to become a powerful single-cell analysis device.

  7. Silicon-Polymer Encapsulation of High-Level Calcine Waste for Transportation or Disposal

    International Nuclear Information System (INIS)

    Loomis, G.G.; Miller, C.M.; Giansiracusa, J.A.; Kimmel, R.; Prewett, S.V.

    2000-01-01

    This report presents the results of an experimental study investigating the potential uses for silicon-polymer encapsulation of High Level Calcine Waste currently stored within the Idaho Nuclear Technology and Engineering Center (INTEC) at the Idaho National Engineering and Environmental Laboratory (INEEL). The study investigated two different applications of silicon polymer encapsulation. One application uses silicon polymer to produce a waste form suitable for disposal at a High Level Radioactive Waste Disposal Facility directly, and the other application encapsulates the calcine material for transportation to an offsite melter for further processing. A simulated waste material from INTEC, called pilot scale calcine, which contained hazardous materials but no radioactive isotopes was used for the study, which was performed at the University of Akron under special arrangement with Orbit Technologies, the originators of the silicon polymer process called Polymer Encapsulation Technology (PET). This document first discusses the PET process, followed by a presentation of past studies involving PET applications to waste problems. Next, the results of an experimental study are presented on encapsulation of the INTEC calcine waste as it applies to transportation or disposal of calcine waste. Results relating to long-term disposal include: (1) a characterization of the pilot calcine waste; (2) Toxicity Characteristic Leaching Procedure (TCLP) testing of an optimum mixture of pilot calcine, polysiloxane and special additives; and, (3) Material Characterization Center testing MCC-1P evaluation of the optimum waste form. Results relating to transportation of the calcine material for a mixture of maximum waste loading include: compressive strength testing, 10-m drop test, melt testing, and a Department of Transportation (DOT) oxidizer test

  8. Synthetic seed technology for encapsulation and regrowth of in vitro ...

    African Journals Online (AJOL)

    In this study, various concentrations of sodium alginate solutions and calcium chloride solutions were tested in order to optimize the size, shape and texture of alginate synthetic seeds or beads for Acacia hybrid bud-sprouting. The shoot buds and axillary buds from in vitro Acacia hybrids, as explants were encapsulated with ...

  9. Encapsulation plant at Forsmark

    International Nuclear Information System (INIS)

    Nystroem, Anders

    2007-08-01

    SKB has already carried out a preliminary study of an encapsulation plant detached from Clab (Central interim storage for spent fuels). This stand-alone encapsulation plant was named FRINK and its assumed siting was the above-ground portion of the final repository, irrespective of the repository's location. The report previously presented was produced in cooperation with BNFL Engineering Ltd in Manchester and the fuel reception technical solution was examined by Gesellschaft fuer Nuklear-Service mbH (GNS) in Hannover and by Societe Generale pour les Techniques Nouvelles (SGN) in Paris. This report is an update of the earlier preliminary study report and is based on the assumption that the encapsulation plant and also the final repository will be sited in the Forsmark area. SKB's main alternative for siting the encapsulation plant is next to Clab. Planning of this facility is ongoing and technical solutions from the planning work have been incorporated in this report. An encapsulation plant placed in proximity to any final repository in Forsmark forms part of the alternative presentation in the application for permission to construct and operate an installation at Clab. The main technical difference between the planned encapsulation plant at Clab and an encapsulation plant at a final repository at Forsmark is how the fuel is managed and prepared before actual encapsulation. Fuel reception at the encapsulation plant in Forsmark would be dry, i.e. there would be no water-filled pools at the facility. Clab is used for verificatory fuel measurements, sorting and drying of the fuel before transport to Forsmark. This means that Clab will require a measure of rebuilding and supplementary equipment. In purely technical terms, the prospects for building an encapsulation plant sited at Forsmark are good. A description of the advantages and drawbacks of siting the encapsulation plant at Clab as opposed to any final repository at Forsmark is presented in a separate report

  10. Encapsulation plant at Forsmark

    Energy Technology Data Exchange (ETDEWEB)

    Nystroem, Anders

    2007-08-15

    SKB has already carried out a preliminary study of an encapsulation plant detached from Clab (Central interim storage for spent fuels). This stand-alone encapsulation plant was named FRINK and its assumed siting was the above-ground portion of the final repository, irrespective of the repository's location. The report previously presented was produced in cooperation with BNFL Engineering Ltd in Manchester and the fuel reception technical solution was examined by Gesellschaft fuer Nuklear-Service mbH (GNS) in Hannover and by Societe Generale pour les Techniques Nouvelles (SGN) in Paris. This report is an update of the earlier preliminary study report and is based on the assumption that the encapsulation plant and also the final repository will be sited in the Forsmark area. SKB's main alternative for siting the encapsulation plant is next to Clab. Planning of this facility is ongoing and technical solutions from the planning work have been incorporated in this report. An encapsulation plant placed in proximity to any final repository in Forsmark forms part of the alternative presentation in the application for permission to construct and operate an installation at Clab. The main technical difference between the planned encapsulation plant at Clab and an encapsulation plant at a final repository at Forsmark is how the fuel is managed and prepared before actual encapsulation. Fuel reception at the encapsulation plant in Forsmark would be dry, i.e. there would be no water-filled pools at the facility. Clab is used for verificatory fuel measurements, sorting and drying of the fuel before transport to Forsmark. This means that Clab will require a measure of rebuilding and supplementary equipment. In purely technical terms, the prospects for building an encapsulation plant sited at Forsmark are good. A description of the advantages and drawbacks of siting the encapsulation plant at Clab as opposed to any final repository at Forsmark is presented in a separate

  11. Design documentation: Krypton encapsulation preconceptual design

    International Nuclear Information System (INIS)

    Knecht, D.A.

    1994-10-01

    US EPA regulations limit the release of Krypton-85 to the environment from commercial facilities after January 1, 1983. In order to comply with these regulations, Krypton-85, which would be released during reprocessing of commercial nuclear fuel, must be collected and stored. Technology currently exists for separation of krypton from other inert gases, and for its storage as a compressed gas in steel cylinders. The requirements, which would be imposed for 100-year storage of Krypton-85, have led to development of processes for encapsulation of krypton within a stable solid matrix. The objective of this effort was to provide preconceptual engineering designs, technical evaluations, and life cycle costing data for comparison of two alternate candidate processes for encapsulation of Krypton-85. This report has been prepared by The Ralph M. Parsons Company for the US Department of Energy

  12. Design documentation: Krypton encapsulation preconceptual design

    Energy Technology Data Exchange (ETDEWEB)

    Knecht, D.A. [Idaho National Engineering Lab., Idaho Falls, ID (United States)

    1994-10-01

    US EPA regulations limit the release of Krypton-85 to the environment from commercial facilities after January 1, 1983. In order to comply with these regulations, Krypton-85, which would be released during reprocessing of commercial nuclear fuel, must be collected and stored. Technology currently exists for separation of krypton from other inert gases, and for its storage as a compressed gas in steel cylinders. The requirements, which would be imposed for 100-year storage of Krypton-85, have led to development of processes for encapsulation of krypton within a stable solid matrix. The objective of this effort was to provide preconceptual engineering designs, technical evaluations, and life cycle costing data for comparison of two alternate candidate processes for encapsulation of Krypton-85. This report has been prepared by The Ralph M. Parsons Company for the US Department of Energy.

  13. Oxygen Measurements in Liposome Encapsulated Hemoglobin

    Science.gov (United States)

    Phiri, Joshua Benjamin

    Liposome encapsulated hemoglobins (LEH's) are of current interest as blood substitutes. An analytical methodology for rapid non-invasive measurements of oxygen in artificial oxygen carriers is examined. High resolution optical absorption spectra are calculated by means of a one dimensional diffusion approximation. The encapsulated hemoglobin is prepared from fresh defibrinated bovine blood. Liposomes are prepared from hydrogenated soy phosphatidylcholine (HSPC), cholesterol and dicetylphosphate using a bath sonication method. An integrating sphere spectrophotometer is employed for diffuse optics measurements. Data is collected using an automated data acquisition system employing lock-in -amplifiers. The concentrations of hemoglobin derivatives are evaluated from the corresponding extinction coefficients using a numerical technique of singular value decomposition, and verification of the results is done using Monte Carlo simulations. In situ measurements are required for the determination of hemoglobin derivatives because most encapsulation methods invariably lead to the formation of methemoglobin, a nonfunctional form of hemoglobin. The methods employed in this work lead to high resolution absorption spectra of oxyhemoglobin and other derivatives in red blood cells and liposome encapsulated hemoglobin (LEH). The analysis using singular value decomposition method offers a quantitative means of calculating the fractions of oxyhemoglobin and other hemoglobin derivatives in LEH samples. The analytical methods developed in this work will become even more useful when production of LEH as a blood substitute is scaled up to large volumes.

  14. Review of metal-matrix encapsulation of solidified radioactive high-level waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-05-01

    Literature describing previous and current work on the encapsulation of solidified high-level waste forms in a metal matrix was reviewed. Encapsulation of either stabilized calcine pellets or glass beads in alloys by casting techniques was concluded to be the most developed and direct approach to fabricating solid metal-matrix waste forms. Further characterizations of the physical and chemical properties of metal-matrix waste forms are still needed to assess the net attributes of metal-encapsulation alternatives. Steady-state heat transfer properties of waste canisters in air and water environments were calculated for four reference waste forms: (1) calcine, (2) glass monoliths, (3) metal-encapsulated calcine, and (4) metal-encapsulated glass beads. A set of criteria for the maximum allowable canister centerline and surface temperatures and heat generation rates per canister at the time of shipment to a Federal repository was assumed, and comparisons were made between canisters of these reference waste forms of the shortest time after reactor discharge that canisters could be filled and the subsequent ''interim'' storage times prior to shipment to a Federal repository for various canister diameters and waste ages. A reference conceptual flowsheet based on existing or developing technology for encapsulation of stabilized calcine pellets is discussed. Conclusions and recommendations are presented

  15. Formation of an interpolymer complex in supercritical carbon dioxide and its application in the encapsulation of probiotics

    CSIR Research Space (South Africa)

    Moolman, S

    2006-02-27

    Full Text Available Traditional encapsulation methods present difficulties for sensitive actives such as probiotics, due to exposure to water/solvents, heat, oxygen, etc. The authors present a novel encapsulation technology utilising the formation of an interpolymer...

  16. Encapsulation of radioactive waste

    International Nuclear Information System (INIS)

    Pordes, O.; Plows, J.P.

    1980-01-01

    A method is described for encapsulating a particular radioactive waste which consists of suspending the waste in a viscous liquid encapsulating material, of synthetic resin monomers or prepolymers, and setting the encapsulating material by addition or condensation polymerization to form a solid material in which the waste is dispersed. (author)

  17. Encapsulation of Active Compounds in Fruit and Vegetable Juice Processing: Current State and Perspectives.

    Science.gov (United States)

    Speranza, Barbara; Petruzzi, Leonardo; Bevilacqua, Antonio; Gallo, Mariangela; Campaniello, Daniela; Sinigaglia, Milena; Corbo, Maria Rosaria

    2017-06-01

    The production of value-added and/or functional juices has increased significantly in recent years, following an increased consumer demand to promote health and/or prevent disease through diet and nutrition. Micro and nano-encapsulation are promising technologies to protect and deliver sensitive compounds, allowing a controlled release in the target sites. This paper offers an overview of current applications, limits and challenges of encapsulation technologies in the production of fruit and vegetable juices, with a particular emphasis on products derived from different botanical sources. © 2017 Institute of Food Technologists®.

  18. Application of image processing technology to problems in manuscript encapsulation. [Codex Hammer

    Science.gov (United States)

    Glackin, D. L.; Korsmo, E. P.

    1983-01-01

    The long term effects of encapsulation individual sheets of the Codex Hammer were investigated. The manuscript was simulated with similar sheets of paper which were photographed under repeatable raking light conditions to enhance their surface texture, encapsulated in plexiglas, cycled in an environmental test chamber, and rephotographed at selected intervals. The film images were digitized, contrast enhanced, geometrically registered, and apodized. An FFT analysis of a control sheet and two experimental sheets indicates no micro-burnishing, but reveals that the ""mesoscale'' deformations with sizes 8mm are degrading monotonically, which is of no concern. Difference image analysis indicates that the sheets were increasingly stressed with time and that the plexiglas did not provide a sufficient environmental barrier under the simulation conditions. The relationship of these results to the Codex itself is to be determined.

  19. Selective encapsulation by Janus particles

    Energy Technology Data Exchange (ETDEWEB)

    Li, Wei, E-mail: wel208@mrl.ucsb.edu [Materials Research Laboratory, University of California, Santa Barbara, California 93106 (United States); Ruth, Donovan; Gunton, James D. [Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States); Rickman, Jeffrey M. [Department of Physics, Lehigh University, Bethlehem, Pennsylvania 18015 (United States); Department of Materials Science and Engineering, Lehigh University, Bethlehem, Pennsylvania 18015 (United States)

    2015-06-28

    We employ Monte Carlo simulation to examine encapsulation in a system comprising Janus oblate spheroids and isotropic spheres. More specifically, the impact of variations in temperature, particle size, inter-particle interaction range, and strength is examined for a system in which the spheroids act as the encapsulating agents and the spheres as the encapsulated guests. In this picture, particle interactions are described by a quasi-square-well patch model. This study highlights the environmental adaptation and selectivity of the encapsulation system to changes in temperature and guest particle size, respectively. Moreover, we identify an important range in parameter space where encapsulation is favored, as summarized by an encapsulation map. Finally, we discuss the generalization of our results to systems having a wide range of particle geometries.

  20. Islet and Stem Cell Encapsulation for Clinical Transplantation

    Science.gov (United States)

    Krishnan, Rahul; Alexander, Michael; Robles, Lourdes; Foster 3rd, Clarence E.; Lakey, Jonathan R.T.

    2014-01-01

    Over the last decade, improvements in islet isolation techniques have made islet transplantation an option for a certain subset of patients with long-standing diabetes. Although islet transplants have shown improved graft function, adequate function beyond the second year has not yet been demonstrated, and patients still require immunosuppression to prevent rejection. Since allogeneic islet transplants have experienced some success, the next step is to improve graft function while eliminating the need for systemic immunosuppressive therapy. Biomaterial encapsulation offers a strategy to avoid the need for toxic immunosuppression while increasing the chances of graft function and survival. Encapsulation entails coating cells or tissue in a semipermeable biocompatible material that allows for the passage of nutrients, oxygen, and hormones while blocking immune cells and regulatory substances from recognizing and destroying the cell, thus avoiding the need for systemic immunosuppressive therapy. Despite advances in encapsulation technology, these developments have not yet been meaningfully translated into clinical islet transplantation, for which several factors are to blame, including graft hypoxia, host inflammatory response, fibrosis, improper choice of biomaterial type, lack of standard guidelines, and post-transplantation device failure. Several new approaches, such as the use of porcine islets, stem cells, development of prevascularized implants, islet nanocoating, and multilayer encapsulation, continue to generate intense scientific interest in this rapidly expanding field. This review provides a comprehensive update on islet and stem cell encapsulation as a treatment modality in type 1 diabetes, including a historical outlook as well as current and future research avenues. PMID:25148368

  1. Do encapsulated heat storage materials really retain their original thermal properties?

    Science.gov (United States)

    Chaiyasat, Preeyaporn; Noppalit, Sayrung; Okubo, Masayoshi; Chaiyasat, Amorn

    2015-01-14

    The encapsulation of Rubitherm®27 (RT27), which is one of the most common commercially supplied heat storage materials, by polystyrene (PS), polydivinyl benzene (PDVB) and polymethyl methacrylate (PMMA) was carried out using conventional radical microsuspension polymerization. The products were purified to remove free RT27 and free polymer particles without RT27. In the cases of PS and PDVB microcapsules, the latent heats of melting and crystallization for RT27 ( and , J/g-RT27) were clearly decreased by the encapsulation. On the other hand, those of the PMMA microcapsules were the same as pure RT27. A supercooling phenomenon was observed not only for PS and PDVB but also for the PMMA microcapsules. These results indicate that the thermal properties of the heat storage materials encapsulated depend on the type of polymer shells, i.e., encapsulation by polymer shell changes the thermal properties of RT27. This is quite different from the idea of other groups in the world, in which they discussed the thermal properties based on the ΔHm and ΔHc values expressed in J/g-capsule, assuming that the thermal properties of the heat storage materials are not changed by the encapsulation. Hereafter, this report should raise an alarm concerning the "wrong" common knowledge behind developing the encapsulation technology of heat storage materials.

  2. Cytokine production induced by non-encapsulated and encapsulated Porphyromonas gingivalis strains

    NARCIS (Netherlands)

    Kunnen, A.; Dekker, D.C.; van Pampus, M.G.; Harmsen, H.J.; Aarnoudse, J.G.; Abbas, F.; Faas, M.M.

    Objective: Although the exact reason is not known, encapsulated gram-negative Porphyromonas gingivalis strains are more virulent than non-encapsulated strains. Since difference in virulence properties may be due to difference in cytokine production following recognition of the bacteria or their

  3. High-efficiency single cell encapsulation and size selective capture of cells in picoliter droplets based on hydrodynamic micro-vortices.

    Science.gov (United States)

    Kamalakshakurup, Gopakumar; Lee, Abraham P

    2017-12-05

    Single cell analysis has emerged as a paradigm shift in cell biology to understand the heterogeneity of individual cells in a clone for pathological interrogation. Microfluidic droplet technology is a compelling platform to perform single cell analysis by encapsulating single cells inside picoliter-nanoliter (pL-nL) volume droplets. However, one of the primary challenges for droplet based single cell assays is single cell encapsulation in droplets, currently achieved either randomly, dictated by Poisson statistics, or by hydrodynamic techniques. In this paper, we present an interfacial hydrodynamic technique which initially traps the cells in micro-vortices, and later releases them one-to-one into the droplets, controlled by the width of the outer streamline that separates the vortex from the flow through the streaming passage adjacent to the aqueous-oil interface (d gap ). One-to-one encapsulation is achieved at a d gap equal to the radius of the cell, whereas complete trapping of the cells is realized at a d gap smaller than the radius of the cell. The unique feature of this technique is that it can perform 1. high efficiency single cell encapsulations and 2. size-selective capturing of cells, at low cell loading densities. Here we demonstrate these two capabilities with a 50% single cell encapsulation efficiency and size selective separation of platelets, RBCs and WBCs from a 10× diluted blood sample (WBC capture efficiency at 70%). The results suggest a passive, hydrodynamic micro-vortex based technique capable of performing high-efficiency single cell encapsulation for cell based assays.

  4. Environmental Decontamination of a Chemical Warfare Simulant Utilizing a Membrane Vesicle-Encapsulated Phosphotriesterase.

    Science.gov (United States)

    Alves, Nathan J; Moore, Martin; Johnson, Brandy J; Dean, Scott N; Turner, Kendrick B; Medintz, Igor L; Walper, Scott A

    2018-05-09

    While technologies for the remediation of chemical contaminants continue to emerge, growing interest in green technologies has led researchers to explore natural catalytic mechanisms derived from microbial species. One such method, enzymatic degradation, offers an alternative to harsh chemical catalysts and resins. Recombinant enzymes, however, are often too labile or show limited activity when challenged with nonideal environmental conditions that may vary in salinity, pH, or other physical properties. Here, we demonstrate how phosphotriesterase encapsulated in a bacterial outer membrane vesicle can be used to degrade the organophosphate chemical warfare agent (CWA) simulant paraoxon in environmental water samples. We also carried out remediation assays on solid surfaces, including glass, painted metal, and fabric, that were selected as representative materials, which could potentially be contaminated with a CWA.

  5. The Effects of Biopolymer Encapsulation on Total Lipids and Cholesterol in Egg Yolk during in Vitro Human Digestion

    Directory of Open Access Journals (Sweden)

    Si-Kyung Lee

    2013-08-01

    Full Text Available The purpose of this study was to examine the effect of biopolymer encapsulation on the digestion of total lipids and cholesterol in egg yolk using an in vitro human digestion model. Egg yolks were encapsulated with 1% cellulose, pectin, or chitosan. The samples were then passed through an in vitro human digestion model that simulated the composition of mouth saliva, stomach acid, and the intestinal juice of the small intestine by using a dialysis tubing system. The change in digestion of total lipids was monitored by confocal fluorescence microscopy. The digestion rate of total lipids and cholesterol in all egg yolk samples dramatically increased after in vitro human digestion. The digestion rate of total lipids and cholesterol in egg yolks encapsulated with chitosan or pectin was reduced compared to the digestion rate of total lipids and cholesterol in other egg yolk samples. Egg yolks encapsulated with pectin or chitosan had lower free fatty acid content, and lipid oxidation values than samples without biopolymer encapsulation. Moreover, the lipase activity decreased, after in vitro digestion, in egg yolks encapsulated with biopolymers. These results improve our understanding of the effects of digestion on total lipids and cholesterol in egg yolk within the gastrointestinal tract.

  6. The Effects of Biopolymer Encapsulation on Total Lipids and Cholesterol in Egg Yolk during in Vitro Human Digestion

    Science.gov (United States)

    Hur, Sun-Jin; Kim, Young-Chan; Choi, Inwook; Lee, Si-Kyung

    2013-01-01

    The purpose of this study was to examine the effect of biopolymer encapsulation on the digestion of total lipids and cholesterol in egg yolk using an in vitro human digestion model. Egg yolks were encapsulated with 1% cellulose, pectin, or chitosan. The samples were then passed through an in vitro human digestion model that simulated the composition of mouth saliva, stomach acid, and the intestinal juice of the small intestine by using a dialysis tubing system. The change in digestion of total lipids was monitored by confocal fluorescence microscopy. The digestion rate of total lipids and cholesterol in all egg yolk samples dramatically increased after in vitro human digestion. The digestion rate of total lipids and cholesterol in egg yolks encapsulated with chitosan or pectin was reduced compared to the digestion rate of total lipids and cholesterol in other egg yolk samples. Egg yolks encapsulated with pectin or chitosan had lower free fatty acid content, and lipid oxidation values than samples without biopolymer encapsulation. Moreover, the lipase activity decreased, after in vitro digestion, in egg yolks encapsulated with biopolymers. These results improve our understanding of the effects of digestion on total lipids and cholesterol in egg yolk within the gastrointestinal tract. PMID:23965957

  7. [Encapsulation of a mechatronic implant that restores the ability to accommodate].

    Science.gov (United States)

    Rheinschmitt, L; Gengenbach, U; Bretthauer, G

    2010-12-01

    In order to restore the ability of accommodation of the human eye, a lens implant manufactured by micro system technology can be used. This highly integrated Artificial Accommodation System contains sensitive electronics as well as moving components in order to adapt its refractive power. One challenge of the production of this system is the encapsulation. It has to be a biocompatible and long-term reliable package. In this paper the advantages of a hermetic glass package over other approaches of encapsulation are introduced. Concepts of production for a glass package are presented. The package is thereby optimised to be placed in the optical path of the eye, but it can also be used for the encapsulation of other implants. © Georg Thieme Verlag KG Stuttgart · New York.

  8. Encapsulation method for atom probe tomography analysis of nanoparticles

    International Nuclear Information System (INIS)

    Larson, D.J.; Giddings, A.D.; Wu, Y.; Verheijen, M.A.; Prosa, T.J.; Roozeboom, F.; Rice, K.P.; Kessels, W.M.M.; Geiser, B.P.; Kelly, T.F.

    2015-01-01

    Open-space nanomaterials are a widespread class of technologically important materials that are generally incompatible with analysis by atom probe tomography (APT) due to issues with specimen preparation, field evaporation and data reconstruction. The feasibility of encapsulating such non-compact matter in a matrix to enable APT measurements is investigated using nanoparticles as an example. Simulations of field evaporation of a void, and the resulting artifacts in ion trajectory, underpin the requirement that no voids remain after encapsulation. The approach is demonstrated by encapsulating Pt nanoparticles in an ZnO:Al matrix created by atomic layer deposition, a growth technique which offers very high surface coverage and conformality. APT measurements of the Pt nanoparticles are correlated with transmission electron microscopy images and numerical simulations in order to evaluate the accuracy of the APT reconstruction. - Highlights: • Pt nanoparticles were analyzed using atom probe tomography and TEM. • The particles were prepared by encapsulation using atomic layer deposition. • Simulation of field evaporation near a void results in aberrations in ion trajectories. • Apparent differences between TEM and APT analyses are reconciled through simulation of field evaporation from a low-field matrix containing high-field NPs; ion trajectory aberrations are shown to lead to an apparent mixing of the matrix into the NPs.

  9. Silk sericin-alginate-chitosan microcapsules: hepatocytes encapsulation for enhanced cellular functions.

    Science.gov (United States)

    Nayak, Sunita; Dey, Sanchareeka; Kundu, Subhas C

    2014-04-01

    The encapsulation based technology permits long-term delivery of desired therapeutic products in local regions of body without the need of immunosuppressant drugs. In this study microcapsules composed of sericin and alginate micro bead as inner core and with an outer chitosan shell are prepared. This work is proposed for live cell encapsulation for potential therapeutic applications. The sericin protein is obtained from cocoons of non-mulberry silkworm Antheraea mylitta. The sericin-alginate micro beads are prepared via ionotropic gelation under high applied voltage. The beads further coated with chitosan and crosslinked with genipin. The microcapsules developed are nearly spherical in shape with smooth surface morphology. Alamar blue assay and confocal microscopy indicate high cell viability and uniform encapsulated cell distribution within the sericin-alginate-chitosan microcapsules indicating that the microcapsules maintain favourable microenvironment for the cells. The functional analysis of encapsulated cells demonstrates that the glucose consumption, urea secretion rate and intracellular albumin content increased in the microcapsules. The study suggests that the developed sericin-alginate-chitosan microcapsule contributes towards the development of cell encapsulation model. It also offers to generate enriched population of metabolically and functionally active cells for the future therapeutics especially for hepatocytes transplantation in acute liver failure. Copyright © 2014 Elsevier B.V. All rights reserved.

  10. The encapsulation of an amphiphile into polystyrene microspheres of narrow size distribution

    Directory of Open Access Journals (Sweden)

    Pellach Michal

    2011-12-01

    Full Text Available Abstract Encapsulation of compounds into nano- or microsized organic particles of narrow size distribution is of increasing importance in fields of advanced imaging and diagnostic techniques and drug delivery systems. The main technology currently used for encapsulation of molecules within uniform template particles while retaining their size distribution is based on particle swelling methodology, involving penetration of emulsion droplets into the particles. The swelling method, however, is efficient for encapsulation only of hydrophobic compounds within hydrophobic template particles. In order to be encapsulated, the molecules must favor the hydrophobic phase of an organic/aqueous biphasic system, which is not easily achieved for molecules of amphiphilic character. The following work overcomes this difficulty by presenting a new method for encapsulation of amphiphilic molecules within uniform hydrophobic particles. We use hydrogen bonding of acid and base, combined with a pseudo salting out effect, for the entrapment of the amphiphile in the organic phase of a biphasic system. Following the entrapment in the organic phase, we demonstrated, using fluorescein and (antibiotic tetracycline as model molecules, that the swelling method usually used only for hydrophobes can be expanded and applied to amphiphilic molecules.

  11. Elementary study of encapsulation of radioisotope battery prototype based on 63Ni radio-voltaic effect

    International Nuclear Information System (INIS)

    Gao Hui; Zhang Huaming; Luo Shunzhong; Wang Heyi; Fu Zhonghua

    2012-01-01

    For isotope battery application, it is necessary to encapsulate in a certain method. After having accomplished selection of material composing and proportion, procedure and encapsulating process based on GD3217Y detector. the different types of device come from untouched, loaded by slip of stainless steel with or without 63 Ni isotope were encapsulated respectively. Despite necessary reliability of package has been evaluated in the previous work. in view of specialty due to the incorporation of radioactive isotopes into device, the reliability issue must be further taken into account for actual application. Hence, we emphasize on the comparison about electrical capability of types of devices under the different situations, namely, before and after encapsulation, the natural aging and artificial accelerated aging. The results of the comparison indicate that the adoption of the method of the encapsulation supply effectively stable electrical capability at the condition of ensuring safety of radioactive source besides improving environmental adaptability for device. Further, it offers technological support for the encapsulation of radioisotope battery based on β radio-voltaic effect. (authors)

  12. Micro-Encapsulated Phase Change Materials: A Review of Encapsulation, Safety and Thermal Characteristics

    Directory of Open Access Journals (Sweden)

    Ahmed Hassan

    2016-10-01

    Full Text Available Phase change materials (PCMs have been identified as potential candidates for building energy optimization by increasing the thermal mass of buildings. The increased thermal mass results in a drop in the cooling/heating loads, thus decreasing the energy demand in buildings. However, direct incorporation of PCMs into building elements undermines their structural performance, thereby posing a challenge for building integrity. In order to retain/improve building structural performance, as well as improving energy performance, micro-encapsulated PCMs are integrated into building materials. The integration of microencapsulation PCMs into building materials solves the PCM leakage problem and assures a good bond with building materials to achieve better structural performance. The aim of this article is to identify the optimum micro-encapsulation methods and materials for improving the energy, structural and safety performance of buildings. The article reviews the characteristics of micro-encapsulated PCMs relevant to building integration, focusing on safety rating, structural implications, and energy performance. The article uncovers the optimum combinations of the shell (encapsulant and core (PCM materials along with encapsulation methods by evaluating their merits and demerits.

  13. Ultra-high resolution optical coherence tomography for encapsulation quality inspection

    KAUST Repository

    Czajkowski, Jakub

    2011-08-28

    We present the application of ultra-high resolution optical coherence tomography (UHR-OCT) in evaluation of thin, protective films used in printed electronics. Two types of sample were investigated: microscopy glass and organic field effect transistor (OFET) structure. Samples were coated with thin (1-3 μm) layer of parylene C polymer. Measurements were done using experimental UHR-OCT device based on a Kerr-lens mode locked Ti: sapphire femtosecond laser, photonic crystal fibre and modified, free-space Michelson interferometer. Submicron resolution offered by the UHR-OCT system applied in the study enables registration of both interfaces of the thin encapsulation layer. Complete, volumetric characterisation of protective layers is presented, demonstrating possibility to use OCT for encapsulation quality inspection. © Springer-Verlag 2011.

  14. Note: Automated optical focusing on encapsulated devices for scanning light stimulation systems

    International Nuclear Information System (INIS)

    Bitzer, L. A.; Benson, N.; Schmechel, R.

    2014-01-01

    Recently, a scanning light stimulation system with an automated, adaptive focus correction during the measurement was introduced. Here, its application on encapsulated devices is discussed. This includes the changes an encapsulating optical medium introduces to the focusing process as well as to the subsequent light stimulation measurement. Further, the focusing method is modified to compensate for the influence of refraction and to maintain a minimum beam diameter on the sample surface

  15. Stability Comparison of Free and Encapsulated Lactobacilus casei ATCC 393 in Yoghurt for Long Time Storage

    Directory of Open Access Journals (Sweden)

    Oana Lelia POP

    2016-11-01

    Full Text Available An innovative method of L. casei ATCC 393 encapsulation has been reported in the present study using pectin combined with alginate. The aim of this study was to investigate the effect of encapsulation on the survival of L. casei ATCC 393 in yoghurt during long time storage, free or encapsulated in alginate and alginate pectin microspheres, and influence over yoghurt properties, particularly acidification. Over 35 days of storage in yoghurt, the encapsulated probiotic cells proved a higher viability compared with free probiotic cells. An even higher viability and stability was observed for the samples where pectin was used. Pectin acts as prebiotic during encapsulation of L. casei ATCC 393.

  16. Encapsulation of antioxidant phenolic compounds extracted from spent coffee grounds by freeze-drying and spray-drying using different coating materials.

    Science.gov (United States)

    Ballesteros, Lina F; Ramirez, Monica J; Orrego, Carlos E; Teixeira, José A; Mussatto, Solange I

    2017-12-15

    Freeze-drying and spray-drying techniques were evaluated for encapsulation of phenolic compounds (PC) extracted from spent coffee grounds. Additionally, the use of maltodextrin, gum arabic and a mixture of these components (ratio 1:1) as wall material to retain the PC and preserve their antioxidant activity was also assessed. The contents of PC and flavonoids (FLA), as well as the antioxidant activity of the encapsulated samples were determined in order to verify the efficiency of each studied condition. Additional analyses for characterization of the samples were also performed. Both the technique and the coating material greatly influenced the encapsulation of antioxidant PC. The best results were achieved when PC were encapsulated by freeze-drying using maltodextrin as wall material. Under these conditions, the amount of PC and FLA retained in the encapsulated sample corresponded to 62% and 73%, respectively, and 73-86% of the antioxidant activity present in the original extract was preserved. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. The Effect of Alcohol on Bead Performance of Encapsulated Iron Using Deacetylated Glucomannan

    Directory of Open Access Journals (Sweden)

    Wardhani Dyah H.

    2018-01-01

    Full Text Available The success of encapsulation to protect iron from inhibitor degradation or oxidation depends on many factors including the excipient characteritics. Glucomannan, a neutral heterosaccharide, has a potential for the excipient. To improve the excipient performances, glucomannan is deacetylated to remove the acetyl groups by reacted with Na2CO3. This deacylated glucomannan is subject to bead formation after iron loading. The alcohol solution is commonly used in bead forming as dehydration medium during the encapsulation process. The objective of this work was to study the effect of alcohol on the bead performance of encapsulated iron using deacetylated glucomannan. The bead forming was conducted by dropping the excipient into ethanol and isopropyl alcohol (IPA solution at various concentrations (50, 60, 70, 80 and 90% and two condition temperatures (27-30° and 7-10°C. The encapsulation samples were subject to yield (YE and efficiency of encapsulation (EE. The concentration of alcohol showed a positive impact on the yield and efficiency of encapsulation. Ethanol has a better performance compared with that of IPA regarding yield and efficiency of encapsulation. The optimum of yield bead formation (69.67% and highest EE (66.80% were obtained at 90% ethanol. Temperature of dehydration did not affect the YE and EE significantly.

  18. Low Hysteresis Carbon Nanotube Transistors Constructed via a General Dry-Laminating Encapsulation Method on Diverse Surfaces.

    Science.gov (United States)

    Yang, Yi; Wang, Zhongwu; Xu, Zeyang; Wu, Kunjie; Yu, Xiaoqin; Chen, Xiaosong; Meng, Yancheng; Li, Hongwei; Qiu, Song; Jin, Hehua; Li, Liqiang; Li, Qingwen

    2017-04-26

    Electrical hysteresis in carbon nanotube thin-film transistor (CNTTFT) due to surface adsorption of H 2 O/O 2 is a severe obstacle for practical applications. The conventional encapsulation methods based on vacuum-deposited inorganic materials or wet-coated organic materials have some limitations. In this work, we develop a general and highly efficient dry-laminating encapsulation method to reduce the hysteresis of CNTTFTs, which may simultaneously realize the construction and encapsulation of CNTTFT. Furthermore, by virtue of dry procedure and wide compatibility of PMMA, this method is suitable for the construction of CNTTFT on diverse surface including both inorganic and organic dielectric materials. Significantly, the dry-encapsulated CNTTFT exhibits very low or even negligible hysteresis with good repeatability and air stability, which is greatly superior to the nonencapsulated and wet-encapsulated CNTTFT with spin-coated PMMA. The dry-laminating encapsulation strategy, a kind of technological innovation, resolves a significant problem of CNTTFT and therefore will be promising in facile transferring and packaging the CNT films for high-performance optoelectronic devices.

  19. Elementary study on encapsulation reliability of radioisotope battery prototype based on 63Ni Radio-Voltaic effect

    International Nuclear Information System (INIS)

    Gao Hui; Zhang Huaming; Luo Shunzhong; Wang Heyi

    2012-01-01

    For isotope battery application, it is necessary to encapsulate in a certain method. After having accomplished selection of material composing and proportion, procedure and encapsulating process based on GD3217Y detector, the different types of device come from untouched, loaded by slip of stainless steel with or without 63 Ni isotope were encapsulated respectively. Despite necessary reliability of package was evaluated in the previous work, in view of specialty due to the incorporation of radioactive isotopes into device, the reliability issue must be further taken into account for actual application. Hence, we emphasize on the comparison about electrical capability of types of devices under the different situations, namely, before and after encapsulation, the natural aging and artificial accelerated aging. The results of the comparison indicate that the adoption of the method of the encapsulation supplies effectively stable electrical capability at the condition of ensuring safety of radioactive source besides improving environmental adaptability for device. Further, it offers technological support for the encapsulation of radioisotope battery based on β radio-voltaic effect. (authors)

  20. The Effect of Emulation Formulation to Encapsulation of Fe3O4 Magnetic nanoparticle with Poly (Lactic Acid)

    International Nuclear Information System (INIS)

    Evi Yuliyanti; Sudaryanto; Mujamilah; Yoki Yulizar

    2008-01-01

    The research to study the effect of emulsion formulation to encapsulation Fe 3 O 4 magnetic nanoparticle with Poly(Lactic Acid) (PLA) has been done. Microemulsion by ultrasonic probe is used in encapsulation process and continued by solvent evaporation. Emulsion formulation has been varied by changing oil phase volume in the oil in water (o/w) emulsion system from 6 mL, 8 mL, 10 mL, 12 mL and 14 mL, whereas water phase volume is constant (55 mL). Sample characterization is carried on by Scanning Electron Microscope (SEM) to know the morphology and sample size. X-Ray Diffractometer (XRD) is used to identify the phase, Vibrating Sample Magnetometer (VSM) is used to measure magnetic saturation while Neutron Activation Analysis (NAA) is used to measure encapsulation percentage of Fe 3 O 4 with PLA. The smallest nanosphere is resulted by emulsion formulation (o/w) of 14/55 with the main sample size 382 nm. The maximum magnetic saturation of Fe 3 O 4 + PLA nanosphere is 2.556 emu/g and encapsulation percentage is 24.94 %. (author)

  1. Characterising encapsulated nuclear waste using cosmic-ray muon tomography

    International Nuclear Information System (INIS)

    Clarkson, A.; Hamilton, D.J.; Hoek, M.; Ireland, D.G.; Kaiser, R.; Keri, T.; Lumsden, S.; Mahon, D.F.; McKinnon, B.; Murray, M.; Nutbeam-Tuffs, S.; Yang, G.; Johnstone, J.R.; Shearer, C.; Zimmerman, C.

    2015-01-01

    Tomographic imaging techniques using the Coulomb scattering of cosmic-ray muons have been shown previously to successfully identify and characterise low- and high-Z materials within an air matrix using a prototype scintillating-fibre tracker system. Those studies were performed as the first in a series to assess the feasibility of this technology and image reconstruction techniques in characterising the potential high-Z contents of legacy nuclear waste containers for the U.K. Nuclear Industry. The present work continues the feasibility study and presents the first images reconstructed from experimental data collected using this small-scale prototype system of low- and high-Z materials encapsulated within a concrete-filled stainless-steel container. Clear discrimination is observed between the thick steel casing, the concrete matrix and the sample materials assayed. These reconstructed objects are presented and discussed in detail alongside the implications for future industrial scenarios

  2. Characterising encapsulated nuclear waste using cosmic-ray muon tomography

    Science.gov (United States)

    Clarkson, A.; Hamilton, D. J.; Hoek, M.; Ireland, D. G.; Johnstone, J. R.; Kaiser, R.; Keri, T.; Lumsden, S.; Mahon, D. F.; McKinnon, B.; Murray, M.; Nutbeam-Tuffs, S.; Shearer, C.; Yang, G.; Zimmerman, C.

    2015-03-01

    Tomographic imaging techniques using the Coulomb scattering of cosmic-ray muons have been shown previously to successfully identify and characterise low- and high-Z materials within an air matrix using a prototype scintillating-fibre tracker system. Those studies were performed as the first in a series to assess the feasibility of this technology and image reconstruction techniques in characterising the potential high-Z contents of legacy nuclear waste containers for the U.K. Nuclear Industry. The present work continues the feasibility study and presents the first images reconstructed from experimental data collected using this small-scale prototype system of low- and high-Z materials encapsulated within a concrete-filled stainless-steel container. Clear discrimination is observed between the thick steel casing, the concrete matrix and the sample materials assayed. These reconstructed objects are presented and discussed in detail alongside the implications for future industrial scenarios.

  3. Encapsulation process for diffraction gratings.

    Science.gov (United States)

    Ratzsch, Stephan; Kley, Ernst-Bernhard; Tünnermann, Andreas; Szeghalmi, Adriana

    2015-07-13

    Encapsulation of grating structures facilitates an improvement of the optical functionality and/or adds mechanical stability to the fragile structure. Here, we introduce novel encapsulation process of nanoscale patterns based on atomic layer deposition and micro structuring. The overall size of the encapsulated structured surface area is only restricted by the size of the available microstructuring and coating devices; thus, overcoming inherent limitations of existing bonding processes concerning cleanliness, roughness, and curvature of the components. Finally, the process is demonstrated for a transmission grating. The encapsulated grating has 97.5% transmission efficiency in the -1st diffraction order for TM-polarized light, and is being limited by the experimental grating parameters as confirmed by rigorous coupled wave analysis.

  4. USE OF RECYCLED POLYMERS FOR ENCAPSULATION OF RADIOACTIVE, HAZARDOUS AND MIXED WASTES

    International Nuclear Information System (INIS)

    LAGERRAAEN, P.R.; KALB, P.D.

    1997-01-01

    Polyethylene encapsulation is a waste treatment technology developed at Brookhaven National Laboratory using thermoplastic polymers to safely and effectively solidify hazardous, radioactive and mixed wastes for disposal. Over 13 years of development and demonstration with surrogate wastes as well as actual waste streams on both bench and full scale have shown this to be a viable and robust technology with wide application. Process development efforts have previously focused on the use of virgin polymer feedstocks. In order to potentially improve process economics and serve to lessen the municipal waste burden, recycled polymers were investigated for use as encapsulating agents. Recycled plastics included low-density polyethylene, linear low-density polyethylene, high-density polyethylene and polypropylene, and were used as a direct substitute for or blended together with virgin resin. Impacts on processing and final waste form performance were examined

  5. Sulfur polymer cement encapsulation of RCRA toxic metals and metal oxides

    International Nuclear Information System (INIS)

    Calhoun, C.L. Jr.; Nulf, L.E.; Gorin, A.H.

    1995-06-01

    A study was conducted to determine the suitability of Sulfur Polymer Cement (SPC) encapsulation technology for the stabilization of RCRA toxic metal and metal oxide wastes. In a series of bench-scale experiments, the effects of sodium sulfide additions to the waste mixture, residence time, and temperature profile were evaluated. In addition, an effort was made to ascertain the degree to which SPC affords chemical stabilization as opposed to physical encapsulation. Experimental results have demonstrated that at the 25 wt % loading level, SPC can effectively immobilize Cr, Cr 2 O 3 , Hg, Pb, and Se to levels below regulatory limits. SPC encapsulation also has been shown to significantly reduce the leachability of other toxic compounds including PbO, PbO 2 , As 2 O 3 , BaO, and CdO. In addition, data has confirmed sulfide conversion of Hg, Pb, PbO, PbO 2 , and BaO as the product of their reaction with SPC

  6. Encapsulating contact allergens in liposomes, ethosomes, and polycaprolactone may affect their sensitizing properties

    DEFF Research Database (Denmark)

    Madsen, Jakob Torp; Vogel, Stefan; Johansen, Jeanne Duus

    2011-01-01

    Attempts to improve formulation of topical products are a continuing process and the development of micro- and nanovesicular systems as well as polymeric microparticles has led to marketing of topical drugs and cosmetics using these technologies. Encapsulation of some well-known contact allergens...... in ethanolic liposomes have been reported to enhance allergenicity compared with the allergens in similar vehicles without liposomes. The present report includes data on more sensitization studies using the mouse local lymph node assay with three contact allergens encapsulated in different dermal drug...... dichromate compared with control solutions. However, encapsulating the lipophilic contact allergen dinitrochlorobenzene (DNCB) in polycaprolactone reduced the sensitizing capacity to 1211 ± 449 compared with liposomes (7602 ± 2658) and in acetone:olive oil (4:1) (5633 ± 666). The same trend was observed...

  7. Poly (DADMAC) encapsulation in PES microcapsules utilizing gamma radiation

    International Nuclear Information System (INIS)

    Francis, Sanju; Varshney, Lalit; Tirumalesh, Keesari; Sabharwal, Sunil

    2009-01-01

    In this communication, a method for encapsulation of a polymeric resin using radiation technology is reported. The quaternary ammonium resin, polydiallyldimethylammonium chloride (PDADMAC) was incorporated in the core of a preformed hollow polyethersulfone microcapsule, using radiation technology, for the extraction of anions from aqueous solutions. The idea was to introduce the monomer into the porous microcapsules and initiate polymerization by radiation to trap the polymer formed inside the capsule. The resultant capsule was able to take up and exchange some anions (F - , Cl - , Br - , NO 3 2- and SO 4 2- ) at relatively low concentrations

  8. A novel type of electrochemical sensor based on ferromagnetic carbon-encapsulated iron nanoparticles for direct determination of hemoglobin in blood samples.

    Science.gov (United States)

    Matysiak, Edyta; Donten, Mikolaj; Kowalczyk, Agata; Bystrzejewski, Michal; Grudzinski, Ireneusz P; Nowicka, Anna M

    2015-02-15

    An effective, fast, facile and direct electrochemical method of determination of hemoglobin (Hb) in blood sample without any sample preparation is described. The method is accomplished by using the ferromagnetic electrode modifier (carbon-encapsulated iron nanoparticles) and an external magnetic field. The successful voltammetric determination of hemoglobin is achieved in PBS buffer as well as in the whole blood sample. The obtained results show the excellent electroactivity of Hb. The measurements are of high sensitivity and good reproducibility. The detection limit is estimated to be 0.7 pM. The electrochemical determination data were compared with the gravimetric data obtained with a quartz crystal microbalance. The agreement between these results is very good. The changes of the electrode surface morphology before and after Hb detection are monitored by electron microscopy. The functionality of the electrochemical sensor is tested with human and rat blood samples. The concentration of hemoglobin in the blood samples determined by using voltammetric/gravimetric detection is in perfect agreement with the data obtained from typical clinical analysis. Copyright © 2014 Elsevier B.V. All rights reserved.

  9. Characterization of encapsulated quantum dots via electron channeling contrast imaging

    Energy Technology Data Exchange (ETDEWEB)

    Deitz, Julia I.; McComb, David W. [Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Carnevale, Santino D. [Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); De Graef, Marc [Department of Materials Science and Engineering, Carnegie Mellon University, Pittsburgh, Pennsylvania 15213 (United States); Grassman, Tyler J., E-mail: grassman.5@osu.edu [Department of Materials Science and Engineering, The Ohio State University, Columbus, Ohio 43210 (United States); Department of Electrical and Computer Engineering, The Ohio State University, Columbus, Ohio 43210 (United States)

    2016-08-08

    A method for characterization of encapsulated epitaxial quantum dots (QD) in plan-view geometry using electron channeling contrast imaging (ECCI) is presented. The efficacy of the method, which requires minimal sample preparation, is demonstrated with proof-of-concept data from encapsulated (sub-surface) epitaxial InAs QDs within a GaAs matrix. Imaging of the QDs under multiple diffraction conditions is presented, establishing that ECCI can provide effectively identical visualization capabilities as conventional two-beam transmission electron microscopy. This method facilitates rapid, non-destructive characterization of sub-surface QDs giving immediate access to valuable nanostructural information.

  10. Investigation of test methods, material properties, and processes for solar cell encapsulants. Annual report

    Energy Technology Data Exchange (ETDEWEB)

    Willis, P. B.; Baum, B.; Schnitzer, H. S.

    1980-07-01

    The goal of this program is to identify, evaluate, and recommend encapsulant materials and processes for the production of cost-effective, long-life solar cell modules. Technical activities during the past year have covered a number of topics and have emphasized the development of solar module encapsulation technology that employs ethylene/vinyl acetate, copolymer (EVA) as the pottant. These activities have included: (1) continued production of encapsulation grade EVA in sheet form to meet the needs of the photovoltaic industry; (2) investigations of three non-blocking techniques for EVA sheet; (3) performed an economic analysis of the high volume production of each pottant in order to estimate the large volume selling price (EVA, EPDM, aliphatic urethane, PVC plastisol, and butyl acrylate); (4) initiated an experimental corrosion protection program to determine if metal components could be successfully protected by encapsulation; (5) began an investigation to determine the maximum temperature which can be tolerated by the candidate pottant material in the event of hot spot heating or other temperature override; (6) continuation of surveys of potentially useful outer cover materials; and (7) continued with the accelerated artificial weathering of candidate encapsulation materials. Study results are presented. (WHK)

  11. Synthesis of alumina ceramic encapsulation for self-healing materials on thermal barrier coating

    Science.gov (United States)

    Golim, O. P.; Prastomo, N.; Izzudin, H.; Hastuty, S.; Sundawa, R.; Sugiarti, E.; Thosin, K. A. Z.

    2018-03-01

    Durability of Thermal Barrier Coating or TBC can be optimized by inducing Self-Healing capabilities with intermetallic materials MoSi2. Nevertheless, high temperature operation causes the self-healing materials to become oxidized and lose its healing capabilities. Therefore, a method to introduce ceramic encapsulation for MoSi2 is needed to protect it from early oxidation. The encapsulation process is synthesized through a simple precipitation method with colloidal aluminum hydroxide as precursor and variations on calcination process. Semi-quantitative analysis on the synthesized sample is done by using X-ray diffraction (XRD) method. Meanwhile, qualitative analysis on the morphology of the encapsulation was carried out by using Scanning Electron Microscope (SEM) and Field Emission Scanning Electron Microscope (FESEM) equipped with dual Focus Ion Beam (FIB). The result of the experiment shows that calcination process significantly affects the final characteristic of encapsulation. The optimum encapsulation process was synthesized by colloidal aluminum hydroxide as a precursor, with a double step calcination process in low pressure until 900 °C.

  12. The effect of VMP35 supplement ingredients encapsulated in a novel Phospholipid Prodosome SK713 SLP nutrient delivery technology on properties of live human blood.

    OpenAIRE

    Kenneth Blum; B. William Downs; Steven Kushner; Ted Aloisio; Frans J. Cronjé

    2015-01-01

    Background: In North America digestive malfunction in terms of disintegration, dissolution, and absorption of food and nutrients, is a widespread malady. Malabsorption is also an exacerbating factor in most chronic degenerative diseases that might benefit from dietary supplementation. The purpose of this experiment was to determine, as shown by changes in properties of live blood, whether, a novel soy-lecithin-phospholipid-nutrient encapsulation technology could promote rapid bioavailability ...

  13. Development of PLGA–PEG encapsulated miltefosine based drug delivery system against visceral leishmaniasis

    Energy Technology Data Exchange (ETDEWEB)

    Kumar, Rishikesh; Sahoo, Ganesh Chandra [Biomedical and Nanomedicine Department, Rajendra Memorial Research Institute Medical Science (ICMR) (India); Pandey, Krishna; Das, V.N.R.; Topno, Roshan K. [Clinical Medicine Department, Rajendra Memorial Research Institute Medical Science (ICMR) (India); Ansari, Md Yousuf [Pharmacoinformatics Department, National Institute Pharmaceutica Research and Education Industrial Area, Hajipur (India); Rana, Sindhuprava [Biomedical and Nanomedicine Department, Rajendra Memorial Research Institute Medical Science (ICMR) (India); Das, Pradeep [Molecular Biology Department, Rajendra Memorial Research Institute Medical Science (ICMR) (India)

    2016-02-01

    Targeted drug delivery systems are ideal technology to increase the maximum mechanism of action with smaller dose, we have developed miltefosine encapsulated PLGA–PEG nanoparticles (PPEM) to target macrophage of infected tissues against Leishmania donovani. The structural characterization of PLGA–PEG by transmission electron microscopy (TEM) has shown a size range of 10 to 15 nm. Synthesis and drug encapsulation confirmed by dynamic light scattering (DLS) and Fourier transform infrared spectroscopy (FTIR) and confirmed NP encapsulation. The dose of nano encapsulated miltefosine decreased by fifty percent as compared to that of a conventional miltefosine and Amphoterecin B. The inhibition of amastigotes in the splenic tissue with nano encapsulated miltefosine (23.21 ± 23) was significantly more than the conventional miltefosine (89.22 ± 52.7) and Amphoterecin B (94.12 ± 55.1). This study signifies that there is an increased contact surface area of the nano encapsulated drug and significant reduction in size, improved the efficacy in both in vitro and in vivo study than that of the conventional miltefosine, Amphoterecin B. - Graphical abstract: The analyses of detailed structure characterized by TEM and DLS confirmed the nano-size of the particle 10–20 nm and FTIR confirmed for antileishmanial drug encapsulation in to PLGA–PEG. The dose of miltefosine is decreased by fifty percent as the IC50 value is decreased from 0.2 to 0.1 μg. Further inhibitions of amastigotes in the splenic tissue with these nanoparticles are significantly more than the conventional miltefosine and PLGA–PEG encapsulated Amphoterecin B (23.21 ± 23/89.09 ± 52.7/92.12 ± 55.1). - Highlights: • Synthesis of PLGA-PEG encapsulated miltefosine nanoparticles has been done. • An IC50 value of PPEM (0.1 ug/ml), miltefosine (0.2 μg/ml) and AmpB (1 μg/ml) were observed two fold better efficacies. • Inhibition of amastigotes of PPEM (23.21 ± 23) was significantly more than

  14. Encapsulation of nuclear wastes

    International Nuclear Information System (INIS)

    Arnold, J.L.; Boyle, R.W.

    1978-01-01

    Toxic waste materials are encapsulated by the method wherein the waste material in liquid or finely divided solid form is uniformly dispersed in a vinyl ester resin or an unsaturated polyester and the resin cured under conditions that the exotherm does not rise above the temperature at which the integrity of the encapsulating material is destroyed

  15. Encapsulating contact allergens in liposomes, ethosomes, and polycaprolactone may affect their sensitizing properties

    DEFF Research Database (Denmark)

    Madsen, Jakob Torp; Vogel, Stefan; Johansen, Jeanne Duus

    2011-01-01

    Attempts to improve formulation of topical products are a continuing process and the development of micro- and nanovesicular systems as well as polymeric microparticles has led to marketing of topical drugs and cosmetics using these technologies. Encapsulation of some well-known contact allergens...... in ethanolic liposomes have been reported to enhance allergenicity compared with the allergens in similar vehicles without liposomes. The present report includes data on more sensitization studies using the mouse local lymph node assay with three contact allergens encapsulated in different dermal drug...... dichromate compared with control solutions. However, encapsulating the lipophilic contact allergen dinitrochlorobenzene (DNCB) in polycaprolactone reduced the sensitizing capacity to 1211 ± 449 compared with liposomes (7602 ± 2658) and in acetone:olive oil (4:1) (5633 ± 666). The same trend was observed...

  16. Transport of encapsulated nuclear fuels

    International Nuclear Information System (INIS)

    Broman, Ulrika; Dybeck, Peter; Ekendahl, Ann-Mari

    2005-12-01

    The transport system for encapsulated fuel is described, including a preliminary drawing of a transport container. In the report, the encapsulation plant is assumed to be located to Oskarshamn, and the repository to Oskarshamn or Forsmark

  17. The effect of VMP35 supplement ingredients encapsulated in a novel Phospholipid Prodosome SK713 SLP nutrient delivery technology on properties of live human blood.

    Directory of Open Access Journals (Sweden)

    Kenneth Blum

    2015-09-01

    Full Text Available Background: In North America digestive malfunction in terms of disintegration, dissolution, and absorption of food and nutrients, is a widespread malady. Malabsorption is also an exacerbating factor in most chronic degenerative diseases that might benefit from dietary supplementation. The purpose of this experiment was to determine, as shown by changes in properties of live blood, whether, a novel soy-lecithin-phospholipid-nutrient encapsulation technology could promote rapid bioavailability and bioactivity of a VMP35 nutraceutical formulation encapsulated within its clustoidal multilamellar Soy Lecithin Phospholipid (SLP liquid SK713 SLP structures. Method: Changes in peripheral blood smears from 38 subjects were measured utilizing peripheral live blood cell imaging (LBCI with phase contrast microscopy. Results: Compared to baseline and control, consistently and reproducibly, the SK713 SLP technology effected positive changes in the blood as demonstrated by observable morphological, hematological and rheological changes five minutes from intake and sustained for at least 30 minutes post intake. Conclusions: These results showed that the SK713 SLP system makes an important contribution by increasing the potential benefits of dietary supplementation to those patients with compromised digestive processes. We encourage additional research on this novel delivery system believing that it has potential impact on future therapy.

  18. Spectral perturbations from silicon diode detector encapsulation and shielding in photon fields.

    Science.gov (United States)

    Eklund, Karin; Ahnesjö, Anders

    2010-11-01

    Silicon diodes are widely used as detectors for relative dose measurements in radiotherapy. The common manufacturing practice is to encapsulate the diodes in plastic for protection and to facilitate mounting in scanning devices. Diodes intended for use in photon fields commonly also have a shield of a high atomic number material (usually tungsten) integrated into the encapsulation to selectively absorb low-energy photons to which silicon diodes would otherwise over-response. However, new response models based on cavity theories and spectra calculations have been proposed for direct correction of the readout from unshielded (e.g., "electron") diodes used in photon fields. This raises the question whether it is correct to assume that the spectrum in a water phantom at the location of the detector cavity is not perturbed by the detector encapsulation materials. The aim of this work is to investigate the spectral effects of typical encapsulations, including shielding, used for clinical diodes. The effects of detector encapsulation of an unshielded and a shielded commercial diode on the spectra at the detector cavity location are studied through Monte Carlo simulations with PENELOPE-2005. Variance reduction based on correlated sampling is applied to reduce the CPU time needed for the simulations. The use of correlated sampling is found to be efficient and to not introduce any significant bias to the results. Compared to reference spectra calculated in water, the encapsulation for an unshielded diode is demonstrated to not perturb the spectrum, while a tungsten shielded diode caused not only the desired decrease in low-energy scattered photons but also a large increase of the primary electron fluence. Measurements with a shielded diode in a 6 MV photon beam proved that the shielding does not completely remove the field-size dependence of the detector response caused by the over-response from low-energy photons. Response factors of a properly corrected unshielded diode

  19. OSR encapsulation basis -- 100-KW

    International Nuclear Information System (INIS)

    Meichle, R.H.

    1995-01-01

    The purpose of this report is to provide the basis for a change in the Operations Safety Requirement (OSR) encapsulated fuel storage requirements in the 105 KW fuel storage basin which will permit the handling and storing of encapsulated fuel in canisters which no longer have a water-free space in the top of the canister. The scope of this report is limited to providing the change from the perspective of the safety envelope (bases) of the Safety Analysis Report (SAR) and Operations Safety Requirements (OSR). It does not change the encapsulation process itself

  20. Point of Injury Sampling Technology for Battlefield Molecular Diagnostics

    Science.gov (United States)

    2011-11-14

    Injury" Sampling Technology for Battlefield Molecular Diagnostics November 14, 2011 Sponsored by Defense Advanced Research Projects Agency (DOD...Date of Contract: April 25, 2011 Short Title of Work: "Point of Injury" Sampling Technology for Battlefield Molecular Diagnostics " Contract...PHASE I FINAL REPORT: Point of Injury, Sampling Technology for Battlefield Molecular Diagnostics . W31P4Q-11-C-0222 (UNCLASSIFIED) P.I: Bernardo

  1. Effect of spray-drying with organic solvents on the encapsulation, release and stability of fish oil.

    Science.gov (United States)

    Encina, Cristian; Márquez-Ruiz, Gloria; Holgado, Francisca; Giménez, Begoña; Vergara, Cristina; Robert, Paz

    2018-10-15

    Fish-oil (FO) was encapsulated with hydroxypropylcelullose (HPC) by conventional spray-drying with water (FO-water) and solvent spray-drying with ethanol (FO-EtOH), methanol (FO-MeOH) and acetone (FO-Acet) in order to study the effect of the solvent on the encapsulation efficiency (EE), microparticle properties and stability of FO during storage at 40 °C. Results showed that FO-Acet presented the highest EE of FO (92.0%), followed by FO-EtOH (80.4%), FO-MeOH (75.0%) and FO-water (71.1%). A decrease of the dielectric constant increased the EE of FO, promoting triglyceride-polymer interactions instead of oil-in-water emulsion retention. FO release profile in aqueous model was similar for all FO-microparticles, releasing only the surface FO, according to Higuchi model. Oxidative stability of FO significantly improved by spray-drying with MeOH, both in surface and encapsulated oil fractions. In conclusion, encapsulation of FO by solvent spray-drying can be proposed as an alternative technology for encapsulation of hydrophobic molecules. Copyright © 2018 Elsevier Ltd. All rights reserved.

  2. Encapsulation of Clay Platelets inside Latex Particles

    NARCIS (Netherlands)

    Voorn, D.J.; Ming, W.; Herk, van A.M.; Fernando, R.H.; Sung, Li-Piin

    2009-01-01

    We present our recent attempts in encapsulating clay platelets inside latex particles by emulsion polymerization. Face modification of clay platelets by cationic exchange has been shown to be insufficient for clay encapsulation, leading to armored latex particles. Successful encapsulation of

  3. Improving ultraviolet photodetection of ZnO nanorods by Cr doped ZnO encapsulation process

    Science.gov (United States)

    Safa, S.; Mokhtari, S.; Khayatian, A.; Azimirad, R.

    2018-04-01

    Encapsulated ZnO nanorods (NRs) with different Cr concentration (0-4.5 at.%) were prepared in two different steps. First, ZnO NRs were grown by hydrothermal method. Then, they were encapsulated by dip coating method. The prepared samples were characterized by X-ray diffraction (XRD), scanning electron microscopy, and ultraviolet (UV)-visible spectrophotometer analyses. XRD analysis proved that Cr incorporated into the ZnO structure successfully. Based on optical analysis, band gap changes in the range of 2.74-3.84 eV. Finally, UV responses of all samples were deeply investigated. It revealed 0.5 at.% Cr doped sample had the most photocurrent (0.75 mA) and photoresponsivity (0.8 A/W) of all which were about three times greater than photocurrent and photoresponsivity of the undoped sample.

  4. Nano-encapsulation of fish oil in nano-liposomes and its application in fortification of yogurt.

    Science.gov (United States)

    Ghorbanzade, Tahere; Jafari, Seid Mahdi; Akhavan, Sahar; Hadavi, Roxana

    2017-02-01

    Fish oils have many dietary benefits, but due to their strong odors and rapid deterioration, their application in food formulations is limited. For these reasons, nano-liposome was used to nano-encapsulate fish oil in this study and encapsulated fish oil was utilized in fortifying yogurt. Physicochemical properties of produced yogurt including pH, acidity, syneresis, fatty acid composition, peroxide value as well as sensory tests were investigated during three weeks storage at 4°C. Nano-liposome encapsulation resulted in a significant reduction in acidity, syneresis and peroxide value. The results of gas chromatography analyses revealed that after 21days storage, yogurt fortified with nano-encapsulated fish oil had a higher DHA and EPA contents than yogurt containing free fish oil. Overall, the results of this study indicates that adding nano-encapsulated fish oil into yogurt gave closer characteristics to control sample in terms of sensory characteristics than yogurt fortified with free fish oil. Copyright © 2016 Elsevier Ltd. All rights reserved.

  5. All-polymer organic semiconductor laser chips: Parallel fabrication and encapsulation

    DEFF Research Database (Denmark)

    Vannahme, Christoph; Klinkhammer, Sönke; Christiansen, Mads Brøkner

    2010-01-01

    Organic semiconductor lasers are of particular interest as tunable visible laser light sources. For bringing those to market encapsulation is needed to ensure practicable lifetimes. Additionally, fabrication technologies suitable for mass production must be used. We introduce all-polymer chips...... comprising encapsulated distributed feedback organic semiconductor lasers. Several chips are fabricated in parallel by thermal nanoimprint of the feedback grating on 4? wafer scale out of poly(methyl methacrylate) (PMMA) and cyclic olefin copolymer (COC). The lasers consisting of the organic semiconductor...... tris(8- hydroxyquinoline) aluminum (Alq3) doped with the laser dye 4-dicyanomethylene-2- methyl-6-(p-dimethylaminostyril)-4H-pyrane (DCM) are hermetically sealed by thermally bonding a polymer lid. The organic thin film is placed in a basin within the substrate and is not in direct contact to the lid...

  6. Investigation on rare earth magnets recycling by organophosphoric extractant encapsulated polymeric beads for separation of dysprosium

    International Nuclear Information System (INIS)

    Yadav, Kartikey K.; Singh, D.K.; Kain, V.

    2017-01-01

    Rare earth elements (REEs) are a basic requirement of the electronics and new industries including green technology. In the present work an organophosphoric extractant encapsulating polyethersulfone (PES) beads has been developed and employed for dysprosium (Dy) separation from aqueous stream. Polyethersulfonic beads encapsulating PC88A were prepared by phase inversion method. During the synthesis of the beads, preparatory parameters were also optimized to obtain best suited beads which were subsequently characterized for their encapsulation capacity and micro structural investigation. The results obtained in the present investigation suggested that PES/PVAJPC88A composite beads could be used for separation of rare earths from aqueous medium obtained from the solubilisation of magnetic scrap materials

  7. Encapsulation methods for organic electrical devices

    Science.gov (United States)

    Blum, Yigal D.; Chu, William Siu-Keung; MacQueen, David Brent; Shi, Yijian

    2013-06-18

    The disclosure provides methods and materials suitable for use as encapsulation barriers in electronic devices. In one embodiment, for example, there is provided an electroluminescent device or other electronic device encapsulated by alternating layers of a silicon-containing bonding material and a ceramic material. The encapsulation methods provide, for example, electronic devices with increased stability and shelf-life. The invention is useful, for example, in the field of microelectronic devices.

  8. Effect of Photon Radiations in Semi-Rigid Artificial Tissue Sensitized by Protoporphyrin IX Encapsulated with Silica Nanoparticles

    Science.gov (United States)

    Makhadmeh, Ghaseb N.; Aziz, Azlan Abdul; Razak, Khairunisak Abdul; Al-Akhras, M.-Ali H.

    2018-02-01

    This study involves the synthesis of Protoporphyrin IX (PpIX) encapsulated with Silica Nanoparticles (SiNPs) as an application for Photodynamic therapy. Semi-rigid artificial tissues with optical features similar to human tissue were used as sample materials to ascertain the efficacy of PpIX encapsulated with SiNPs. The disparity in optical characteristics (transmittance, reflectance, scattering, and absorption) of tissues treated with encapsulated PpIX and naked PpIX under light exposure (Intensity at 408 nm ~1.19 mW/cm2) was explored. The optimal exposure times required for naked PpIX and SiNPs encapsulated PpIX to engulf Red Blood Cells (RBCs) in the artificial tissue were subsequently measured. Comparative analysis showed that the encapsulated PpIX has a 91.5 % higher efficacy than naked PpIX. The results prove the applicability of PpIX encapsulated with SiNP on artificial tissue and possible use on human tissue.

  9. Melting of Pb clusters encapsulated in large fullerenes

    International Nuclear Information System (INIS)

    Delogu, Francesco

    2011-01-01

    Graphical abstract: Encapsulation significantly increases the melting point of nanometer-sized Pb particles with respect to the corresponding unsupported ones. Highlights: → Nanometer-sized Pb particles are encapsulated in fullerene cages. → Their thermal behavior is studied by molecular dynamics simulations. → Encapsulated particles undergo a pressure rise as temperature increases. → Encapsulated particles melt at temperatures higher than unsupported ones. - Abstract: Molecular dynamics simulations have been employed to explore the melting behavior of nanometer-sized Pb particles encapsulated in spherical and polyhedral fullerene cages of suitable size. The encapsulated particles, as well as the corresponding unsupported ones for comparison, were submitted to a gradual temperature rise. Encapsulation is shown to severely affect the thermodynamic behavior of Pb particles due to the different thermal expansion coefficients of particles and cages. This determines a volume constraint that induces a rise of pressure inside the fullerene cages, which operate for particles as rigid confinement systems. The result is that surface pre-melting and melting processes occur in encapsulated particles at temperatures higher than in unsupported ones.

  10. Encapsulation of spent nuclear fuel-safety analysis

    International Nuclear Information System (INIS)

    Soederman, E.

    1983-04-01

    Two methods of encapsulation are studied, both including a copper canister. In one process the copper canister with the spent fuel is filled with copper powder and pressed to solid copper metal at high pressure. In the other process lead is cast around the fuel before the canister is sealed by electron beam welding. The activity decay of the fuel has been going on for 40 years before it arrives to the encapsulation station. This is the basic reason for expecting less activity release and less contamination of the plant than would be the case with fuel recently taken out from the reactors. In analysing the plant safety, experience from the nuclear power plants, from the planning of the Swedish central storage facility for spent fuel (CLAB) and from La Hague has been used. The analysis is also based on experience of todays technology, although it should be possible to improve the encapsulation process further before time has come to actually build the plant. The environment activity release will be very low, both at normal operation and following accidents in the plant. Using very conservative release rates also the most severe anticipated accident in the plant will induce a dose to critical group of only 3 μSv. The staff dose can also be kept low. Due to remote handling, fuel damage will not primarily give staff dose. Of the totally anticipated staff dose of 150 man mSv/year the greatest portion will come from external radiation during repair work in areas where fuel containing canisters by failure can not be taken away. The hot isostatic pressed (HIP) canister process contains more operations than does the lead casting and welding procedure. It is therefore expected to give the highest activity release and staff dose unless extra measures are taken to keep them low. Using remote operation and adequate equipment the encapsulation station with any of the two processes can be built and run with good radiological safety. (author)

  11. Rapid fabrication of Al{sub 2}O{sub 3} encapsulations for organic electronic devices

    Energy Technology Data Exchange (ETDEWEB)

    Ali, Kamran; Ali, Junaid [Department of Mechatronics Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of); Mehdi, Syed Murtuza [Department of Mechanical Engineering, NED University of Engineering and Technology, Karachi 75270 (Pakistan); Choi, Kyung-Hyun, E-mail: amm@jejunu.ac.kr [Department of Mechatronics Engineering, Jeju National University, Jeju 690-756 (Korea, Republic of); An, Young Jin [Jeonnam Science and Technology Promotion Center, Yeongam-gun, Jeollanam-do 526-897 (Korea, Republic of)

    2015-10-30

    Highlights: • Al{sub 2}O{sub 3} encapsulations are being developed through a unique R2R-AALD system. • The encapsulations have resulted in life time enhancement of PVP memristor devices. • The Al{sub 2}O{sub 3} encapsulated memristor performed with superior stability for four weeks. • Encapsulated devices performed efficiently even after bending test for 100 cycles. - Abstract: Organic electronics have earned great reputation in electronic industry yet they suffer technical challenges such as short lifetimes and low reliability because of their susceptibility to water vapor and oxygen which causes their fast degradation. This paper report on the rapid fabrication of Al{sub 2}O{sub 3} encapsulations through a unique roll-to-roll atmospheric atomic layer deposition technology (R2R-AALD) for the life time enhancement of organic poly (4-vinylphenol) (PVP) memristor devices. The devices were then categorized into two sets. One was processed with R2R-AALD Al{sub 2}O{sub 3} encapsulations at 50 °C and the other one was kept as un-encapsulated. The field-emission scanning electron microscopy (FESEM) results revealed that pin holes and other irregularities in PVP films with average arithmetic roughness (R{sub a}) of 9.66 nm have been effectively covered by Al{sub 2}O{sub 3} encapsulation having R{sub a} of 0.92 nm. The X-ray photoelectron spectroscopy XPS spectrum for PVP film showed peaks of C 1s and O 1s at the binding energies of 285 eV and 531 eV, respectively. The respective appearance of Al 2p, Al 2s, and O 1s peaks at the binding energies of 74 eV, 119 eV, and 531 eV, confirms the fabrication of Al{sub 2}O{sub 3} films. Electrical current–voltage (I–V) measurements confirmed that the Al{sub 2}O{sub 3} encapsulation has a huge influence on the performance, robustness and life time of memristor devices. The Al{sub 2}O{sub 3} encapsulated memristor performed with superior stability for four weeks whereas the un-encapsulated devices could only last for one

  12. New process encapsulates

    International Nuclear Information System (INIS)

    Mueller, J.J.

    1982-01-01

    The results of the various aspects of this study indicate that the encapsulation process is not only capable of reducing the percent of Radon-222 emanation but also reduces the possibility of the leaching of toxic elements. Radon-222 emanation after solidification showed a 93.51% reduction from the slurry. The Gamma Spectral Analyses of short-lived Radon daughters supported the above findings. Leach studies on solidified refinery waste and transformer oils indicate there is a significant reduction in the possibility of toxic substances leaching out of the solidified samples. Further studies are needed to confirm the results of this investigation; however, the present findings indicate that the process could substantially reduce Radon-222 exhalation into the environment from uranium tailings ponds and reduce toxic leachates from hazardous waste materials

  13. Photopolymerizable liquid encapsulants for microelectronic devices

    Science.gov (United States)

    Baikerikar, Kiran K.

    2000-10-01

    Plastic encapsulated microelectronic devices consist of a silicon chip that is physically attached to a leadframe, electrically interconnected to input-output leads, and molded in a plastic that is in direct contact with the chip, leadframe, and interconnects. The plastic is often referred to as the molding compound, and is used to protect the chip from adverse mechanical, thermal, chemical, and electrical environments. Encapsulation of microelectronic devices is typically accomplished using a transfer molding process in which the molding compound is cured by heat. Most transfer molding processes suffer from significant problems arising from the high operating temperatures and pressures required to fill the mold. These aspects of the current process can lead to thermal stresses, incomplete mold filling, and wire sweep. In this research, a new strategy for encapsulating microelectronic devices using photopolymerizable liquid encapsulants (PLEs) has been investigated. The PLEs consist of an epoxy novolac-based vinyl ester resin (˜25 wt.%), fused silica filler (70--74 wt.%), and a photoinitiator, thermal initiator, and silane coupling agent. For these encapsulants, the use of light, rather than heat, to initiate the polymerization allows precise control over when the reaction starts, and therefore completely decouples the mold filling and the cure. The low viscosity of the PLEs allows for low operating pressures and minimizes problems associated with wire sweep. In addition, the in-mold cure time for the PLEs is equivalent to the in-mold cure times of current transfer molding compounds. In this thesis, the thermal and mechanical properties, as well as the viscosity and adhesion of photopolymerizable liquid encapsulants, are reported in order to demonstrate that a UV-curable formulation can have the material properties necessary for microelectronic encapsulation. In addition, the effects of the illumination time, postcure time, fused silica loading, and the inclusion

  14. New Generation Flask Sampling Technology Final Report

    Energy Technology Data Exchange (ETDEWEB)

    Smith, James R. [AOS, Inc., Colorado Springs, CO (United States)

    2017-11-09

    Scientists are turning their focus to the Arctic, site of one of the strongest climate change signals. A new generation of technologies is required to function within that harsh environment, chart evolution of its trace gases and provide new kinds of information for models of the atmosphere. Our response to the solicitation tracks how global atmospheric monitoring was launched more than a half century ago; namely, acquisition of discrete samples of air by flask and subsequent analysis in the laboratory. AOS is proposing to develop a new generation of flask sampling technology. It will enable the new Arctic programs to begin with objective high density sampling of the atmosphere by UAS. The Phase I program will build the prototype flask technology and show that it can acquire and store mol fractions of CH4 and CO2 and value of δ13C with good fidelity. A CAD model will be produced for the entire platform including a package with 100 flasks and the airframe with auto-pilot, electronic propulsion and ground-to-air communications. A mobile flask analysis station will be prototyped in Phase I and designed to final form in Phase II. It expends very small sample per analysis and will interface directly to the flask package integrated permanently into the UAS fuselage. Commercial Applications and Other Benefits: • The New Generation Flask Sampling Technology able to provide a hundred or more samples of air per UAS mission. • A mobile analysis station expending far less sample than the existing ones and small enough to be stationed at the remote sites of Arctic operations. • A new form of validation for continuous trace gas observations from all platforms including the small UAS. • Further demonstration to potential customers of the AOS capabilities to invent, build, deploy and exploit entire platforms for observations of Earth’s atmosphere and ocean. Key Words: Flask Sampler, Mobile Analysis Station, Trace Gas, CO2, CH4, δC13, UAS, Baseline Airborne Observatory

  15. Hybrid chip-on-board LED module with patterned encapsulation

    Science.gov (United States)

    Soer, Wouter Anthon; Helbing, Rene; Huang, Guan

    2018-02-27

    Different wavelength conversion materials, or different concentrations of a wavelength conversion material are used to encapsulate the light emitting elements of different colors of a hybrid light emitting module. In an embodiment of this invention, second light emitting elements (170) of a particular color are encapsulated with a transparent second encapsulant (120;420;520), while first light emitting elements (160) of a different color are encapsulated with a wavelength conversion first encapsulant (110;410;510). In another embodiment of this invention, a particular second set of second and third light emitting elements (170,580) of different colors is encapsulated with a different encapsulant than another first set of first light emitting elements (160).

  16. Sulfur polymer cement encapsulation of oily matrix mixed low-level sludge

    International Nuclear Information System (INIS)

    Calhoun, C.L. Jr.; Nulf, L.E.; Fedorov, V.V.

    1996-01-01

    The U.S. Department of Energy (DOE) has been investigating a variety of stabilization technologies for the treatment of mixed low-level debris and sludges. Sulfur Polymer Cement (SPC) is being considered as one possible alternative final waste form for that segment of these wastes that does not readily lend itself to vitrification and/or grout stabilization. Earlier work demonstrated that SPC effectively immobilizes some Resource Conservation and Recovery Act (RCRA) toxic metal and metal salt species. However, the use of SPC as an encapsulant is relatively new, and the scope of tested waste streams has been limited. Accordingly, the authors' intent was to identify and ascertain the effects of process variables on final waste form properties for encapsulated mixed low-level sludge. The authors conducted an optimal design factorial experiment to study the effects of eight variables in twelve trials with replication. Factors for consideration included waste spike level, waste loading, additive type, additive loading, mixing method, hold time, hold temperature, and cooling rate. Toxic metal leachability was assessed for samples and was the basis for factor comparison. Trials were typically conducted with 150-g of total material per batch. Experimental results demonstrated that a number of process variables -- process hold time, cooling rate, waste loading, spike level, process temperature, additive type, and additive loading -- can influence toxic metal leachability. Also, the effects of different factors may weigh more heavily on different individual species; accordingly, optimum process conditions may vary considerably based on waste composition

  17. Self-assembled nanotextures impart broadband transparency to glass windows and solar cell encapsulants

    Science.gov (United States)

    Liapis, Andreas C.; Rahman, Atikur; Black, Charles T.

    2017-10-01

    Most optoelectronic components and consumer display devices require glass or plastic covers for protection against the environment. Optical reflections from these encapsulation layers can degrade the device performance or lessen the user experience. Here, we use a highly scalable self-assembly based approach to texture glass surfaces at the nanoscale, reducing reflections by such an extent so as to make the glass essentially invisible. Our nanotextures provide broadband antireflection spanning visible and infrared wavelengths (450-2500 nm) that is effective even at large angles of incidence. This technology can be used to improve the performance of photovoltaic devices by eliminating reflection losses, which can be as much as 8% for glass encapsulated cells. In contrast, solar cells encapsulated with nanotextured glass generate the same photocurrent as when operated without a cover. Ultra-transparent windows having surface nanotextures on both sides can withstand three times more optical fluence than commercial broadband antireflection coatings, making them useful for pulsed laser applications.

  18. Thin film Encapsulations of Flexible Organic Light Emitting Diodes

    Directory of Open Access Journals (Sweden)

    Tsai Fa-Ta

    2016-01-01

    Full Text Available Various encapsulated films for flexible organic light emitting diodes (OLEDs were studied in this work, where gas barrier layers including inorganic Al2O3 thin films prepared by atomic layer deposition, organic Parylene C thin films prepared by chemical vapor deposition, and their combination were considered. The transmittance and water vapor transmission rate of the various organic and inorgabic encapsulated films were tested. The effects of the encapsulated films on the luminance and current density of the OLEDs were discussed, and the life time experiments of the OLEDs with these encapsulated films were also conducted. The results showed that the transmittance are acceptable even the PET substrate were coated two Al2O3 and Parylene C layers. The results also indicated the WVTR of the PET substrate improved by coating the barrier layers. In the encapsulation performance, it indicates the OLED with Al2O3 /PET, 1 pair/PET, and 2 pairs/PET presents similarly higher luminance than the other two cases. Although the 1 pair/PET encapsulation behaves a litter better luminance than the 2 pairs/PET encapsulation, the 2 pairs/PET encapsulation has much better life time. The OLED with 2 pairs/PET encapsulation behaves near double life time to the 1 pair encapsulation, and four times to none encapsulation.

  19. Effect of encapsulation of selected probiotic cell on survival in simulated gastrointestinal tract condition

    Directory of Open Access Journals (Sweden)

    Hasiah Ayama

    2014-06-01

    Full Text Available The health benefits of probiotic bacteria have been led to their increasing use in foods. Encapsulation has been investigated to improve their survival. In this study, the selection, encapsulation and viability of lactic acid bacteria (LAB with probiotic properties in simulated gastrointestinal tract (GIT condition were investigated. One hundred and fifty isolates of LAB were obtained from 30 samples of raw cow and goat milk and some fermented foods. Nine isolates could survive under GIT condition and only 3 isolates exhibited an antimicrobial activity against all food-borne pathogenic bacteria. Among them, 2 isolates (CM21 and CM53 exhibited bile salt hydrolase activity on glycocholate and glycodeoxycholate agar plates and were identified as Lactobacillus plantarum. CM53 was selected for encapsulation using 1-3% alginate and 2% Hi-maize resistant starch by emulsion system. Viability and releasing ability of encapsulated CM53 in simulated GIT condition was increased in accordance to the alginate concentration and incubation time, respectively.

  20. An examination of sulfur polymer cement as a waste encapsulation agent

    International Nuclear Information System (INIS)

    McNew, E.B.

    1995-01-01

    Sulfur polymer cement (SPC) is a unique material having potential applications for hazardous and radioactive waste encapsulation. This material was originally developed by the US Bureau of Mines as an acid and chemical resistant construction cement and has since been applied in tie waste encapsulation field. The material is easily prepared from elemental sulfur and organic dienes. It is an easy to use low-viscosity thermoplastic, and has many favorable properties such as low porosity, high compressive strength, and resistance to chemical attack. The results of several invetigations on this material will be discussed, and include: (1) the chemical form and physical structure of the material, (2) the compressive strength of cylindrical test samples after gamma radiation testing, (3) the aqueous leaching behavior of lead, cerium, cesium, cobalt, and strontium from SPC-ash mixtures at room and elevated temperatures, (4) the casting compatibility of mixtures of SPC with different waste materials, (5) the ability of SPC to encapsulate elemental mercury contaminated soils, (6) laboratory and field studies of SPC biocorrosion by Thiobacillus bacteria, (7) small scale (10 kg) SPC-ash monolith casting studies, and (8) methods for the formulation of a grade of SPC more applicable to the encapsulation of aggregate waste materials

  1. Plastic encapsulated, dye sensitised photovoltaic cells

    Energy Technology Data Exchange (ETDEWEB)

    Potter, R.J.; Otley, L.C.; Durrant, J.R.; Haque, S.; Xu, C. [Imperial College of Science, Technology and Medicine, London (United Kingdom); Holmes, A.B.; Park, T.; Schulte, N. [Cambridge Univ. (United Kingdom)

    2004-07-01

    The report presents the results of a collaborative project that aimed to demonstrate the technical feasibility of a plastic-encapsulated, solid state, dye-sensitised solar cell (DSSC) with an energy conversion efficiency (ECE) of at least 3%. DSSCs offer a possible 'step change' in photovoltaic technology resulting in lower costs compared with existing technologies. The project involved a series of eight main tasks: the development of first and second generation HTM electrolytes; the development of polymer-supported electrolytes; the development of low temperature electrode coating procedures; dye development; cell assembly and testing; component integration; and overall process development. A wide range of innovative HTMs have been synthesised, including materials incorporating both hole-transporting and ion-chelating functional groups. The ruthenium-based dye, N3, remained the preferred sensitising component. The project has produced a system that can routinely achieve over 5% ECE at 0.1 Sun illumination on 1 cm{sup 2} cells using polymer-supported electrolytes.

  2. Preliminary investigation of cryopreservation by encapsulation ...

    African Journals Online (AJOL)

    Protocorm-like bodies (PLBs) of Brassidium Shooting Star, a new commercial ornamental orchid hybrid, were cryopreserved by an encapsulation-dehydration technique. The effects of PLB size, various sucrose concentrations in preculture media and sodium alginate concentration for encapsulation were the main ...

  3. Hybrid Encapsulated Ionic Liquids for Post-Combustion Carbon Dioxide (CO2) Capture

    Energy Technology Data Exchange (ETDEWEB)

    Brennecke, Joan; Degnan, Thomas; McCready, Mark; Stadtherr, Mark; Stolaroff, Joshuah; Ye, Congwang

    2016-09-30

    Ionic liquids (ILs) and Phase Change Ionic Liquids (PCILs) are excellent materials for selective removal of carbon dioxide from dilute post-combustion streams. However, they are typically characterized as having high viscosities, which impairs their effectiveness due to mass transfer limitations, caused by the high viscosities. In this project, we are examining the benefits of encapsulating ILs and PCILs in thin polymeric shells to produce particles of approximately 100 to 600 μm in diameter that can be used in a fluidized bed absorber. The particles are produced by microencapsulation of the ILs and PCILs in CO2-permeable polymer shells. Here we report on the synthesis of the IL and PCIL materials, measurements of thermophysical properties including CO2 capacity and reprotonation equilibrium and kinetics, encapsulation of the ILs and PCILs, mechanical and thermodynamic testing of the encapsulated materials, development of a rate based model of the absorber, and the design of a laboratory scale unit to test the encapsulated particles for CO2 capture ability and efficiency. We show that the IL/PCIL materials can be successfully encapsulated, that they retain CO2 uptake capacity, and that the uptake rates are increased relative to a stagnant sample of IL liquid or PCIL powder.

  4. The encapsulated nuclear heat source reactor for proliferation-resistant nuclear energy

    International Nuclear Information System (INIS)

    Brown, N.W.; Hossain, Q.; Carelli, M.D.; Conway, L.; Dzodzo, M.; Greenspan, E.; Saphier, D.

    2001-01-01

    The encapsulated nuclear heat source (ENHS) is a modular reactor that was selected by the 1999 DOE NERI program as a candidate ''Generation-IV'' reactor concept. It is a fast neutron spectrum reactor cooled by Pb-Bi using natural circulation. It is designed for passive load following, for high level of passive safety, and for 15 years without refueling. One of the unique features of the ENHS is that the fission-generated heat is transferred from the primary coolant to the secondary coolant across the reactor vessel wall by conduction-providing for an essentially sealed module that is easy to install and replace. Because the fuel is encapsulated within a heavy steel container throughout its life it provides a unique improvement to the proliferation resistance of the nuclear fuel cycle. This paper presents the innovative technology of the ENHS. (author)

  5. Matrix-encapsulated waste forms: application to idealized systems, commercial and SRP/INEL wastes, hydrated radiophases and encapsulant phases

    International Nuclear Information System (INIS)

    Roy, R.; Vance, E.R.; McCarthy, G.J.; White, W.B.

    1981-01-01

    This paper describes the encapsulation strategy as applied to microscopic-scale encapsulation in ceramics composed of micron-sized grains of possibly more leachable radiophases intimately surrounded by micron-sized grains of more insoluble phases. The encapsulation approach should be valid, almost axiomatic, for defense waste. However, there are still problems to be investigated experimentally. These are (a) because of the dilution, it is difficult to confirm the geometry of the radionuclide-bearing phases relative to that of the matrix: one almost has to use the inverse approach by making leach measurements, (b) deciding between using the highly reactive oxyhydroxide sludges themselves or sintered calcine to be coated, (c) verification of the insolubility of the encapsulant phases in a variety of groundwaters, and (d) the production of ceramics of near-zero porosity, using hot-isostatic pressing, or incorporation in either silicate or phosphate cements

  6. A Spatially Offset Raman Spectroscopy Method for Non-Destructive Detection of Gelatin-Encapsulated Powders

    Directory of Open Access Journals (Sweden)

    Kuanglin Chao

    2017-03-01

    Full Text Available Non-destructive subsurface detection of encapsulated, coated, or seal-packaged foods and pharmaceuticals can help prevent distribution and consumption of counterfeit or hazardous products. This study used a Spatially Offset Raman Spectroscopy (SORS method to detect and identify urea, ibuprofen, and acetaminophen powders contained within one or more (up to eight layers of gelatin capsules to demonstrate subsurface chemical detection and identification. A 785-nm point-scan Raman spectroscopy system was used to acquire spatially offset Raman spectra for an offset range of 0 to 10 mm from the surfaces of 24 encapsulated samples, using a step size of 0.1 mm to obtain 101 spectral measurements per sample. As the offset distance was increased, the spectral contribution from the subsurface powder gradually outweighed that of the surface capsule layers, allowing for detection of the encapsulated powders. Containing mixed contributions from the powder and capsule, the SORS spectra for each sample were resolved into pure component spectra using self-modeling mixture analysis (SMA and the corresponding components were identified using spectral information divergence values. As demonstrated here for detecting chemicals contained inside thick capsule layers, this SORS measurement technique coupled with SMA has the potential to be a reliable non-destructive method for subsurface inspection and authentication of foods, health supplements, and pharmaceutical products that are prepared or packaged with semi-transparent materials.

  7. Sol-gel method for encapsulating molecules

    Science.gov (United States)

    Brinker, C. Jeffrey; Ashley, Carol S.; Bhatia, Rimple; Singh, Anup K.

    2002-01-01

    A method for encapsulating organic molecules, and in particular, biomolecules using sol-gel chemistry. A silica sol is prepared from an aqueous alkali metal silicate solution, such as a mixture of silicon dioxide and sodium or potassium oxide in water. The pH is adjusted to a suitably low value to stabilize the sol by minimizing the rate of siloxane condensation, thereby allowing storage stability of the sol prior to gelation. The organic molecules, generally in solution, is then added with the organic molecules being encapsulated in the sol matrix. After aging, either a thin film can be prepared or a gel can be formed with the encapsulated molecules. Depending upon the acid used, pH, and other processing conditions, the gelation time can be from one minute up to several days. In the method of the present invention, no alcohols are generated as by-products during the sol-gel and encapsulation steps. The organic molecules can be added at any desired pH value, where the pH value is generally chosen to achieve the desired reactivity of the organic molecules. The method of the present invention thereby presents a sufficiently mild encapsulation method to retain a significant portion of the activity of the biomolecules, compared with the activity of the biomolecules in free solution.

  8. Multilayer encapsulated mesoporous silica nanospheres as an oral sustained drug delivery system for the poorly water-soluble drug felodipine

    Energy Technology Data Exchange (ETDEWEB)

    Hu, Liang [Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016 (China); Sun, Hongrui [English Teaching Department, School of Basic Courses, Shenyang Pharmaceutical University, Wenhua Road 103, Shenyang 110016 (China); Zhao, Qinfu; Han, Ning; Bai, Ling; Wang, Ying; Jiang, Tongying [Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016 (China); Wang, Siling, E-mail: silingwang@syphu.edu.cn [Department of Pharmaceutics, Shenyang Pharmaceutical University, P.O. Box 32, Liaoning Province, Shenyang 110016 (China)

    2015-02-01

    We used a combination of mesoporous silica nanospheres (MSN) and layer-by-layer (LBL) self-assembly technology to establish a new oral sustained drug delivery system for the poorly water-soluble drug felodipine. Firstly, the model drug was loaded into MSN, and then the loaded MSN were repeatedly encapsulated by chitosan (CHI) and acacia (ACA) via LBL self-assembly method. The structural features of the samples were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption. The encapsulating process was monitored by zeta-potential and surface tension measurements. The physical state of the drug in the samples was characterized by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). The influence of the multilayer with different number of layers on the drug release rate was studied using thermal gravimetric analysis (TGA) and surface tension measurement. The swelling effect and the structure changes of the multilayer were investigated to explore the relationship between the drug release behavior and the state of the multilayer under different pH conditions. The stability and mucosa adhesive ability of the prepared nanoparticles were also explored. After multilayer coating, the drug release rate was effectively controlled. The differences in drug release behavior under different pH conditions could be attributed to the different states of the multilayer. And the nanoparticles possessed good stability and strong mucosa adhesive ability. We believe that this combination offers a simple strategy for regulating the release rate of poorly water-soluble drugs and extends the pharmaceutical applications of inorganic materials and polymers. - Highlights: • A combination of inorganic and organic materials was applied. • Mesoporous silica nanospheres (MSN) were used as drug carriers. • Chitosan and acacia were encapsulated through layer-by-layer self-assembly. • The release rate of the poorly

  9. Multilayer encapsulated mesoporous silica nanospheres as an oral sustained drug delivery system for the poorly water-soluble drug felodipine

    International Nuclear Information System (INIS)

    Hu, Liang; Sun, Hongrui; Zhao, Qinfu; Han, Ning; Bai, Ling; Wang, Ying; Jiang, Tongying; Wang, Siling

    2015-01-01

    We used a combination of mesoporous silica nanospheres (MSN) and layer-by-layer (LBL) self-assembly technology to establish a new oral sustained drug delivery system for the poorly water-soluble drug felodipine. Firstly, the model drug was loaded into MSN, and then the loaded MSN were repeatedly encapsulated by chitosan (CHI) and acacia (ACA) via LBL self-assembly method. The structural features of the samples were studied using scanning electron microscopy (SEM), transmission electron microscopy (TEM) and nitrogen adsorption. The encapsulating process was monitored by zeta-potential and surface tension measurements. The physical state of the drug in the samples was characterized by differential scanning calorimetry (DSC) and X-ray diffractometry (XRD). The influence of the multilayer with different number of layers on the drug release rate was studied using thermal gravimetric analysis (TGA) and surface tension measurement. The swelling effect and the structure changes of the multilayer were investigated to explore the relationship between the drug release behavior and the state of the multilayer under different pH conditions. The stability and mucosa adhesive ability of the prepared nanoparticles were also explored. After multilayer coating, the drug release rate was effectively controlled. The differences in drug release behavior under different pH conditions could be attributed to the different states of the multilayer. And the nanoparticles possessed good stability and strong mucosa adhesive ability. We believe that this combination offers a simple strategy for regulating the release rate of poorly water-soluble drugs and extends the pharmaceutical applications of inorganic materials and polymers. - Highlights: • A combination of inorganic and organic materials was applied. • Mesoporous silica nanospheres (MSN) were used as drug carriers. • Chitosan and acacia were encapsulated through layer-by-layer self-assembly. • The release rate of the poorly

  10. Encapsulated microsensors for reservoir interrogation

    Science.gov (United States)

    Scott, Eddie Elmer; Aines, Roger D.; Spadaccini, Christopher M.

    2016-03-08

    In one general embodiment, a system includes at least one microsensor configured to detect one or more conditions of a fluidic medium of a reservoir; and a receptacle, wherein the receptacle encapsulates the at least one microsensor. In another general embodiment, a method include injecting the encapsulated at least one microsensor as recited above into a fluidic medium of a reservoir; and detecting one or more conditions of the fluidic medium of the reservoir.

  11. Final Scientific/Technical Report (DOE F 241.3) Next-Generation LED Package Architectures Enabled by Thermally Conductive Transparent Encapsulants

    Energy Technology Data Exchange (ETDEWEB)

    Murugaiah, Anand [Momentive Performance Materials Quartz, Inc., Strongsville, OH (United States)

    2016-12-30

    The objective of this program is to generate novel LED package designs that would provide 30% improvement in lumen/$ output. This was to be achieved by improving thermal management in encapsulants/ phosphors to reduce their temperatures. Currently, the heat that is generated during down conversion of blue light to longer wavelengths by the phosphors dispersed in the encapsulant does not have optimum thermal pathways for dissipation due to poor thermal conductivity of the encapsulant material. Additionally, high temperature in the encapsulant during operation is one of the primary failure modes in LED luminaires resulting in much shorter than expected life. The thermal issues manifest in color instability (yellowing, browning), cracking and hot spots in the encapsulant leading to failures. This work explored boron nitride (hBN) as thermal fillers in encapsulants to improve thermal conductivity while minimally impacting optical properties. Various approaches to Boron Nitride (BN) were evaluated and over 380 samples were generated to down select appropriate BN morphologies. We developed a range or BN materials for enabling thermal properties while attempting to minimally impact to optical properties.

  12. Preparation of thermosensitive magnetic liposome encapsulated recombinant tissue plasminogen activator for targeted thrombolysis

    Energy Technology Data Exchange (ETDEWEB)

    Hsu, Hao-Lung [Department of Chemical and Materials Engineering, Chang Gung University, Kwei-San, Taoyuan 33302, Taiwan, ROC (China); Chen, Jyh-Ping, E-mail: jpchen@mail.cgu.edu.tw [Department of Chemical and Materials Engineering, Chang Gung University, Kwei-San, Taoyuan 33302, Taiwan, ROC (China); Department of Plastic and Reconstructive Surgery and Craniofacial Research Center, Chang Gung Memorial Hospital, Kwei-San, Taoyuan 33305, Taiwan, ROC (China); Graduate Institute of Health Industry and Technology, Research Center for Industry of Human Ecology, Chang Gung University of Science and Technology, Kwei-San, Taoyuan 33302, Taiwan, ROC (China); Department of Materials Engineering, Ming Chi University of Technology, Tai-Shan, New Taipei City 24301, Taiwan, ROC (China)

    2017-04-01

    Recombinant tissue plasminogen activator (rtPA) was encapsulated in thermosensitive magnetic liposome (TML) prepared from 1,2-dipalmitoyl-sn-glycero-3-phosphocholine, distearolyphosphatidyl ethanolamine-N-poly(ethylene glycol) 2000, cholesterol and Fe{sub 3}O{sub 4} magnetic nanoparticles by solvent evaporation/sonication and freeze-thaw cycles method. Response surface methodology was proved to be a powerful tool to predict the drug encapsulation efficiency and temperature-sensitive drug release. Validation experiments verified the accuracy of the model that provides a simple and effective method for fabricating TML with controllable encapsulation efficiency and predictable temperature-sensitive drug release behavior. The prepared samples were characterized for physico-chemical properties by dynamic light scattering, transmission electron microscopy, X-ray diffraction and differential scanning calorimetry. Temperature-sensitive release of rtPA could be confirmed from in vitro thrombolysis experiments. A thrombolytic drug delivery system using TML could be proposed for magnetic targeted delivery of rtPA to the site of thrombus followed by temperature-triggered controlled drug release in an alternating magnetic field. - Highlights: • rtPA and Fe{sub 3}O{sub 4} MNP were encapsulated in thermosensitive magnetic liposome (TML). • RSM could predict the drug encapsulation efficiency and temperature-sensitive drug release from TML. • Temperature-sensitive release of rtPA was confirmed from in vitro thrombolysis experiments. • TML-rtPA will be useful as a magnetic targeted nanodrug to improve clinical thrombolytic therapy.

  13. Encapsulation of antioxidant phenolic compounds extracted from spent coffee grounds by freeze-drying and spray-drying using different coating materials

    DEFF Research Database (Denmark)

    Ballesteros, Lina F.; Ramirez, Monica J.; Orrego, Carlos E.

    2017-01-01

    Freeze-drying and spray-drying techniques were evaluated for encapsulation of phenolic compounds (PC) extracted from spent coffee grounds. Additionally, the use of maltodextrin, 29 gum arabic and a mixture of these components (ratio 1:1) as wall material to retain the PC and preserve their antiox......Freeze-drying and spray-drying techniques were evaluated for encapsulation of phenolic compounds (PC) extracted from spent coffee grounds. Additionally, the use of maltodextrin, 29 gum arabic and a mixture of these components (ratio 1:1) as wall material to retain the PC and preserve...... the technique and the coating material greatly influenced the encapsulation of antioxidant PC. The best results were achieved when PC were encapsulated by freeze-drying using maltodextrin as wall material. Under these conditions, the amount of PC and FLA retained in the encapsulated sample corresponded to 62...

  14. Encapsulation - how it will be achieved

    International Nuclear Information System (INIS)

    Barlow, P.

    1990-01-01

    The work of the new Encapsulation Plant at British Nuclear Fuel Limited's (BNFL) Sellafield site is described in this article. Intermediate-level radioactive materials are encapsulated in a cement matrix in 500 litre stainless steel drums suitable for storage, transport and disposal. The drums will be stored in an above-ground air-cooled store until UK Nirex Limited have built the planned underground disposal facility. The concept of product specification is explored as it applies to the four stages of nuclear waste management, namely, processing, storage, transport and disposal. By following this approach the encapsulation plant will work within government regulations and the public concerns over safety and environmental issues can be met. U.K

  15. Encapsulation in the food industry: a review.

    Science.gov (United States)

    Gibbs, B F; Kermasha, S; Alli, I; Mulligan, C N

    1999-05-01

    Encapsulation involves the incorporation of food ingredients, enzymes, cells or other materials in small capsules. Applications for this technique have increased in the food industry since the encapsulated materials can be protected from moisture, heat or other extreme conditions, thus enhancing their stability and maintaining viability. Encapsulation in foods is also utilized to mask odours or tastes. Various techniques are employed to form the capsules, including spray drying, spray chilling or spray cooling, extrusion coating, fluidized bed coating, liposome entrapment, coacervation, inclusion complexation, centrifugal extrusion and rotational suspension separation. Each of these techniques is discussed in this review. A wide variety of foods is encapsulated--flavouring agents, acids bases, artificial sweeteners, colourants, preservatives, leavening agents, antioxidants, agents with undesirable flavours, odours and nutrients, among others. The use of encapsulation for sweeteners such as aspartame and flavours in chewing gum is well known. Fats, starches, dextrins, alginates, protein and lipid materials can be employed as encapsulating materials. Various methods exist to release the ingredients from the capsules. Release can be site-specific, stage-specific or signalled by changes in pH, temperature, irradiation or osmotic shock. In the food industry, the most common method is by solvent-activated release. The addition of water to dry beverages or cake mixes is an example. Liposomes have been applied in cheese-making, and its use in the preparation of food emulsions such as spreads, margarine and mayonnaise is a developing area. Most recent developments include the encapsulation of foods in the areas of controlled release, carrier materials, preparation methods and sweetener immobilization. New markets are being developed and current research is underway to reduce the high production costs and lack of food-grade materials.

  16. Stability of encapsulated beef-like flavourings prepared from enzymatically hydrolysed mushroom proteins with other precursors under conventional and microwave heating.

    Science.gov (United States)

    Lotfy, Shereen N; Fadel, Hoda H M; El-Ghorab, Ahmed H; Shaheen, Mohamed S

    2015-11-15

    A comparative study was carried out between two beef-like flavourings prepared by conventional and microwave heating (CBF and MBF) of enzymatic hydrolysate of mushroom protein with other flavour precursors. GC-MS analysis of the isolated volatiles revealed that the thiol containing compounds were the predominate in both samples. However, MBF comprised higher concentration of these compounds (13.84 ± 0.06%) than CBF (10.74 ± 0.06%). The effect of microencapsulation with gum Arabic by using spray drying on the odour profile and volatile compounds of the two encapsulated samples (E-CBF and E-MBF) was investigated. The results revealed significant qualitative and quantitative variations in the volatiles of both samples. The highly volatile compounds decreased remarkably in concentration with encapsulation, while the pyrazines, thiazoles and disulphides showed opposite trend. The significant decrease in the thiol containing compounds in E-CBF and E-MBF were attributed to their oxidation to other compounds such as disulphide compounds which showed significant increase in the encapsulated samples. Copyright © 2015 Elsevier Ltd. All rights reserved.

  17. ’Point of Injury’ Sampling Technology for Battlefield Molecular Diagnostics

    Science.gov (United States)

    2012-03-17

    Injury" Sampling Technology for Battlefield Molecular Diagnostics March 17,2012 Sponsored by Defense Advanced Research Projects Agency (DOD) Defense...Contract: April 25, 2011 Short Title of Work: "Point of Injury" Sampling Technology for Battlefield Molecular Diagnostics " Contract Expiration Date...SBIR PHASE I OPTION REPORT: Point of Injury, Sampling Technology for Battlefield Molecular Diagnostics . W31P4Q-1 l-C-0222 (UNCLASSIFIED) P.I

  18. Performance of Deacetyled Glucomannan as Iron Encapsulation Excipient

    Directory of Open Access Journals (Sweden)

    Wardhani Dyah H.

    2018-01-01

    Full Text Available Encapsulation protects iron from degradation or oxidation possibilities due to its encapsulation material. Glucomannan (GM is a neutral polysaccharide consist of D-mannose and D-glucose connected with β-1,4 linkage. Deactylation transforms solubility of glucomannan as well as its gel structure. These properties support for excipient application. The aim of this work was to determine performance of deacetylated glucomannan as iron matrix. Deacetylation was conducted heterogeneously. Deacetylation did not change the backbone of GM. Higher alkali concentration has better ability to encapsulate iron. Extended deacetylation time and alkali concentration affect insignificantly on the performance of encapsulation to protect iron from oxidation. The release of iron from the matrix influences by deacetylation degree.

  19. Design and characterization of a 3D encapsulation with silicon vias for radio frequency micro-electromechanical system resonator

    Science.gov (United States)

    Zhao, Ji-Cong; Yuan, Quan; Wang, Feng-Xiang; Kan, Xiao; Han, Guo-Wei; Sun, Ling; Sun, Hai-Yan; Yang, Jin-Ling; Yang, Fu-Hua

    2017-06-01

    In this paper, we present a three-dimensional (3D) vacuum packaging technique at a wafer level for a radio frequency micro-electromechanical system (RF MEMS) resonator, in which low-loss silicon vias is used to transmit RF signals. Au-Sn solder bonding is adopted to provide a vacuum encapsulation as well as electrical conductions. A RF model of the encapsulation cap is established to evaluate the parasitic effect of the packaging, which provides an effective design solution of 3D RF MEMS encapsulation. With the proposed packaging structure, the signal-to-background ratio (SBR) of 24 dB is achieved, as well as the quality factor (Q-factor) of the resonator increases from 8000 to 10400 after packaging. The packaged resonator has a linear frequency-temperature (f-T) characteristic in a temperature range between 0 °C and 100 °C. And the package shows favorable long-term stability of the Q-factor over 200 days, which indicates that the package has excellent hermeticity. Furthermore, the average shear strength is measured to be 43.58 MPa among 10 samples. Project supported by the National Natural Science Foundation of China (Grant Nos. 61234007, 61404136, and 61504130), the Fund from the Ministry of Science and Technology of China (Grant No. 2013YQ16055103), the Key Research & Development Program of Jiangsu Province, China (Grant No. BE2016007-2), and the Major Project of Natural Science Research of the Higher Education Institutions of Jiangsu Province, China (Grant No. 16KJA510006).

  20. Air encapsulation. I. Measurement in a field soil

    International Nuclear Information System (INIS)

    Fayer, M.J.; Hillel, D.

    1986-01-01

    Encapsulated air is an important component of shallow water table fluctuations. Their objective was to measure the quantity and persistence of encapsulated air in a field setting. Using sprinkling rates of either 3.5 x 10 -6 or 3.8 x 10 -5 m s -1 , they brought the water table in a field soil from a depth of 1.5 m to the surface on several occasions. Moisture contents during and after sprinkling were monitored with a neutron probe. Twice following sprinkling, the water table was maintained at the surface for more than 20 d, during which time they continued to monitor moisture contents. With the water table at the surface, differences between the porosity and the measured moisture content were attributed to encapsulated air. Encapsulated air contents ranged from 1.1 to 6.3% of the bulk soil volume, depending on the rate of sprinkling, soil depth, and initial soil moisture content. During ponding, encapsulated air persisted at the 0.3-m depth for up to 28 d. The results indicate that encapsulated air is measurable in a field situation and that its quantity and persistence should be considered in analyzing the results of similar field experiments. 16 references

  1. Designing deoxidation inhibiting encapsulation of metal oxide nanostructures for fluidic and biological applications

    Energy Technology Data Exchange (ETDEWEB)

    Ghosh, Moumita, E-mail: ghoshiisc@gmail.com [Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012 (India); Centre for Nano Science and Engineering, Indian Institute of Science, Bangalore 560012 (India); IV. Institute of Physics, Georg-August-Universität-Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); III. Institute of Physics – Biophysics and Complex Systems, Georg-August-Universität-Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Ghosh, Siddharth [III. Institute of Physics – Biophysics and Complex Systems, Georg-August-Universität-Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Seibt, Michael [IV. Institute of Physics, Georg-August-Universität-Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Schaap, Iwan A.T. [III. Institute of Physics – Biophysics and Complex Systems, Georg-August-Universität-Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Institute of Biological Chemistry, Biophysics and Bioengineering, Heriot-Watt University, Edinburgh EH14 4AS (United Kingdom); Schmidt, Christoph F. [III. Institute of Physics – Biophysics and Complex Systems, Georg-August-Universität-Göttingen, Friedrich-Hund-Platz 1, 37077 Göttingen (Germany); Mohan Rao, G. [Instrumentation and Applied Physics, Indian Institute of Science, Bangalore 560012 (India)

    2016-12-30

    Graphical abstract: To retain atomic structure and morphology of ZnO nanostructures (caused by deoxidation of ZnO) in water/bio-fluids, we propose and demonstrate a robust and inexpensive encapsulation technique using bio-compatible non-ionic surfactant. - Highlights: • Aqueous solutions of ZnO nanorods with and without surfactant are prepared. • With time ZnO nanorods show structural deterioration in different aqueous solutions. • Crystallinity of ZnO nanorods in absence of aqueous solution remain unaffected. • Encapsulation of bio-compatible surfactant in alchohol avoid ZnO deoxidation. • Crystallinity and structure of ZnO nanorods after encapsulation remain unaffected. - Abstract: Due to their photoluminescence, metal oxide nanostructures such as ZnO nanostructures are promising candidates in biomedical imaging, drug delivery and bio-sensing. To apply them as label for bio-imaging, it is important to study their structural stability in a bio-fluidic environment. We have explored the effect of water, the main constituent of biological solutions, on ZnO nanostructures with scanning electron microscopy (SEM) and photoluminescence (PL) studies which show ZnO nanorod degeneration in water. In addition, we propose and investigate a robust and inexpensive method to encapsulate these nanostructures (without structural degradation) using bio-compatible non-ionic surfactant in non-aqueous medium, which was not reported earlier. This new finding is an immediate interest to the broad audience of researchers working in biophysics, sensing and actuation, drug delivery, food and cosmetics technology, etc.

  2. A formulation to encapsulate nootkatone for tick control.

    Science.gov (United States)

    Behle, Robert W; Flor-Weiler, Lina B; Bharadwaj, Anuja; Stafford, Kirby C

    2011-11-01

    Nootkatone is a component of grapefruit oil that is toxic to the disease-vectoring tick, Ixodes scapularis Say, but unfortunately causes phytotoxicity to treated plants and has a short residual activity due to volatility. We prepared a lignin-encapsulated nootkatone formulation to compare with a previously used emulsifiable formulation for volatility, plant phytotoxicity, and toxicity to unfed nymphs of I. scapularis. Volatility of nootkatone was measured directly by trapping nootkatone vapor in a closed system and indirectly by measuring nootkatone residue on treated filter paper after exposure to simulated sunlight (Xenon). After 24 h in the closed system, traps collected only 15% of the nootkatone applied as the encapsulated formulation compared with 40% applied as the emulsifiable formulation. After a 1-h light exposure, the encapsulated formulation retained 92% of the nootkatone concentration compared with only 26% retained by the emulsifiable formulation. For plant phytotoxicity, cabbage, Brassica oleracea L., leaves treated with the encapsulated formulation expressed less necrosis, retaining greater leaf weight compared with leaves treated with the emusifiable formulation. The nootkatone in the emulsifiable formulation was absorbed by cabbage and oat, Avena sativa L., plants (41 and 60% recovered 2 h after application, respectively), as opposed to 100% recovery from the plants treated with encapsulated nootkatone. Using a treated vial technique, encapsulated nootkatone was significantly more toxic to I. scapularis nymphs (LC50 = 20 ng/cm2) compared with toxicity of the emulsifiable formulation (LC50 = 35 ng/cm2). Thus, the encapsulation of nootkatone improved toxicity for tick control, reduced nootkatone volatility, and reduced plant phytotoxicity.

  3. Design and Fabrication of Piezoresistive Based Encapsulated Poly-Si Cantilevers for Bio/chemical Sensing

    Science.gov (United States)

    Krishna, N. P. Vamsi; Murthy, T. R. Srinivasa; Reddy, K. Jayaprakash; Sangeeth, K.; Hegde, G. M.

    Cantilever-based sensing is a growing research field not only within micro regime but also in nano technology. The technology offers a method for rapid, on-line and in-situ monitoring of specific bio/chemical substances by detecting the nanomechanical responses of a cantilever sensor. Cantilever with piezoresistive based detection scheme is more attractive because of its electronics compatibility. Majority of commercially available micromachined piezoresistive sensors are bulk micromachined devices and are fabricated using single crystal silicon wafers. As substrate properties are not important in surface micromachining, the expensive silicon wafers can be replaced by cheaper substrates, such as poly-silicon, glass or plastic. Here we have designed SU-8 based bio/chemical compatible micro electro mechanical device that includes an encapsulated polysilicon piezoresistor for bio/chemical sensing. In this paper we report the design, fabrication and analysis of the encapsulated poly-Si cantilevers. Design and theoretical analysis are carried out using Finite Element Analysis software. For fabrication of poly-silicon piezoresistive cantilevers we followed the surface micromachining process steps. Preliminary characterization of the cantilevers is presented.

  4. The therapeutic effect of nano-encapsulated and nano-emulsion forms of carvacrol on experimental liver fibrosis.

    Science.gov (United States)

    Hussein, Jihan; El-Banna, Mona; Mahmoud, Khaled F; Morsy, Safaa; Abdel Latif, Yasmin; Medhat, Dalia; Refaat, Eman; Farrag, Abdel Razik; El-Daly, Sherien M

    2017-06-01

    The present study aimed to compare the therapeutic efficiency of nano-encapsulated and nano-emulsion carvacrol administration on liver injury in thioacetamide (TAA) treated rats. To fulfill our target, we used sixty male albino rats classified into six groups as follow: control, nano-encapsulated carvacrol, nano-emulsion carvacrol, thioacetamide, treated nano-encapsulated carvacrol and treated nano-emulsion carvacrol groups. Blood samples were collected from all groups and the separated serum was used for analysis of the following biochemical parameters; aspartate aminotransferase (AST), alanine aminotransferase (ALT), S100 B protein, alpha fetoprotein (AFP) and caspase-3. The levels of malondialdehyde (MDA), reduced glutathione (GSH), nitric oxide (NO), monocyte chemoattractant protein-1(MCP-1) and hydroxyproline content were all evaluated in liver tissue homogenate. Histopathological examinations for liver tissues were also performed. Thioacetamide induced hepatic damage in rats as revealed by the significant increase in the levels of serum ALT, AST and produced oxidative stress as displayed by the significant elevation in the levels of hepatic MDA and NO concomitant with a significant decrease in GSH. In addition, thioacetamide significantly increased serum S100B protein, alpha fetoprotein and caspase-3 along with hepatic MCP-1 and hydroxyproline; these results were confirmed by the histopathological investigation. In contrast, nano-encapsulated and nano-emulsion carvacrol were able to ameliorate these negative changes in the thioacetamide injected rats. However, the effect of the nano-encapsulated form of carvacrol was more prominent than the nano-emulsion form. Nano-encapsulated and nano-emulsion carvacrol can ameliorate thioacetamide induced liver injury. These results could be attributed to the potential anti-inflammatory, antioxidant, and anti-apoptotic activities of carvacrol in addition to the effectiveness of the encapsulation technique that can protect

  5. Development of Magnesium Silicate Hydrate cement system for nuclear waste encapsulation

    International Nuclear Information System (INIS)

    Zhang, T.; Vandeperre, L.J.; Cheeseman, C.R.

    2012-01-01

    A novel low pH cement system for encapsulating nuclear industry wastes containing aluminium has been developed using blends of MgO and silica fume (SF). Identification of the hydrated phases in MgO/silica fume samples showed that brucite formed in early stages of hydration and then reacted with the silica fume to produce a magnesium silicate hydrate (M-S-H) gel phase. When all brucite reacts with silica fume a cement system with an equilibrium pH just below 10 was achieved. Selected mixes have been characterized for hydration reactions, setting time and strength development. Mortar samples with w/s ratios of 0.5 and 50% by weight of sand added achieved compressive strengths in excess of 95 MPa after 28 days. The addition of MgCO 3 buffered the early pH and the addition of fine sand particles eliminated shrinkage cracking. The interaction of the optimised mortar with Al metal has been investigated. Al metal strips were firmly bound into the MgO:SF:sand samples and no H 2 gas detected, and this indicates that the novel systems developed in this work have potential for encapsulating certain types of problematic legacy wastes from the nuclear industry. (authors)

  6. Encapsulation of gold nanoparticles into self-assembling protein nanoparticles

    Directory of Open Access Journals (Sweden)

    Yang Yongkun

    2012-10-01

    Full Text Available Abstract Background Gold nanoparticles are useful tools for biological applications due to their attractive physical and chemical properties. Their applications can be further expanded when they are functionalized with biological molecules. The biological molecules not only provide the interfaces for interactions between nanoparticles and biological environment, but also contribute their biological functions to the nanoparticles. Therefore, we used self-assembling protein nanoparticles (SAPNs to encapsulate gold nanoparticles. The protein nanoparticles are formed upon self-assembly of a protein chain that is composed of a pentameric coiled-coil domain at the N-terminus and trimeric coiled-coil domain at the C-terminus. The self-assembling protein nanoparticles form a central cavity of about 10 nm in size, which is ideal for the encapsulation of gold nanoparticles with similar sizes. Results We have used SAPNs to encapsulate several commercially available gold nanoparticles. The hydrodynamic size and the surface coating of gold nanoparticles are two important factors influencing successful encapsulation by the SAPNs. Gold nanoparticles with a hydrodynamic size of less than 15 nm can successfully be encapsulated. Gold nanoparticles with citrate coating appear to have stronger interactions with the proteins, which can interfere with the formation of regular protein nanoparticles. Upon encapsulation gold nanoparticles with polymer coating interfere less strongly with the ability of the SAPNs to assemble into nanoparticles. Although the central cavity of the SAPNs carries an overall charge, the electrostatic interaction appears to be less critical for the efficient encapsulation of gold nanoparticles into the protein nanoparticles. Conclusions The SAPNs can be used to encapsulate gold nanoparticles. The SAPNs can be further functionalized by engineering functional peptides or proteins to either their N- or C-termini. Therefore encapsulation of gold

  7. Encapsulating betalains from Opuntia ficus-indica fruits by ionic gelation: Pigment chemical stability during storage of beads.

    Science.gov (United States)

    Otálora, María Carolina; Carriazo, José Gregorio; Iturriaga, Laura; Osorio, Coralia; Nazareno, Mónica Azucena

    2016-07-01

    Betalain encapsulation was performed by ionic gelation as a stabilization strategy for these natural pigments. Betalains were extracted from purple cactus fruits and encapsulated in calcium-alginate and in combination of calcium alginate and bovine serum albumin. Beads were characterised by scanning electron microscopy and thermal analysis using differential scanning calorimetry and thermogravimetry. Moisture sorption isotherms were determined. Bead morphology was affected by matrix composition. Pigments storage stability was evaluated at different equilibrium relative humidity and temperatures. Pigment composition of beads was determined by HPLC-MS-MS and degradation products were also analysed after storage; betalamic acid being the major one. Both types of matrices protected the encapsulated pigments, being their storage stability better at low relative humidity than that of the non-encapsulated control material. Antiradical activities of beads were proportional to remaining betalain contents. At high relative humidity, there was no protection and low storage stability was observed in the samples. Copyright © 2016 Elsevier Ltd. All rights reserved.

  8. Encapsulation of electroless copper patterns into diamond films

    Energy Technology Data Exchange (ETDEWEB)

    Pimenov, S.M.; Shafeev, G.A.; Lavrischev, S.V. [General Physics Institute, Moscow (Russian Federation)] [and others

    1995-12-31

    The results are reported on encapsulating copper lines into diamond films grown by a DC plasma CVD. The process includes the steps of (i) laser activation of diamond for electroless metal plating, (ii) electroless copper deposition selectively onto the activated surface regions, and (iii) diamond regrowth on the Cu-patterned diamond films. The composition and electrical properties of the encapsulated copper lines were examined, revealing high purity and low electrical resistivity of the encapsulated electroless copper.

  9. Encapsulation of iron nanoparticles in alginate biopolymer for trichloroethylene remediation

    International Nuclear Information System (INIS)

    Bezbaruah, Achintya N.; Shanbhogue, Sai Sharanya; Simsek, Senay; Khan, Eakalak

    2011-01-01

    Nanoscale zero-valent iron (NZVI) particles (10–90 nm) were encapsulated in biodegradable calcium-alginate capsules for the first time for application in environmental remediation. Encapsulation is expected to offers distinct advances over entrapment. Trichloroethylene (TCE) degradation was 89–91% in 2 h, and the reaction followed pseudo first order kinetics for encapsulated NZVI systems with an observed reaction rate constant (k obs ) of 1.92–3.23 × 10 −2 min −1 and a surface normalized reaction rate constant (k sa ) of 1.02–1.72 × 10 −3 L m −2 min −1 . TCE degradation reaction rates for encapsulated and bare NZVI were similar indicating no adverse affects of encapsulation on degradation kinetics. The shelf-life of encapsulated NZVI was found to be four months with little decrease in TCE removal efficiency.

  10. Critical factors affecting cell encapsulation in superporous hydrogels

    International Nuclear Information System (INIS)

    Desai, Esha S; Tang, Mary Y; Gemeinhart, Richard A; Ross, Amy E

    2012-01-01

    We recently showed that superporous hydrogel (SPH) scaffolds promote long-term stem cell viability and cell driven mineralization when cells were seeded within the pores of pre-fabricated SPH scaffolds. The possibility of cell encapsulation within the SPH matrix during its fabrication was further explored in this study. The impact of each chemical component used in SPH fabrication and each step of the fabrication process on cell viability was systematically examined. Ammonium persulfate, an initiator, and sodium bicarbonate, the gas-generating compound, were the two components having significant toxicity toward encapsulated cells at the concentrations necessary for SPH fabrication. Cell survival rates were 55.7% ± 19.3% and 88.8% ± 9.4% after 10 min exposure to ammonium persulfate and sodium bicarbonate solutions, respectively. In addition, solution pH change via the addition of sodium bicarbonate had significant toxicity toward encapsulated cells with cell survival of only 50.3% ± 2.5%. Despite toxicity of chemical components and the SPH fabrication method, cells still exhibited significant overall survival rates within SPHs of 81.2% ± 6.8% and 67.0% ± 0.9%, respectively, 48 and 72 h after encapsulation. This method of cell encapsulation holds promise for use in vitro and in vivo as a scaffold material for both hydrogel matrix encapsulation and cell seeding within the pores. (paper)

  11. Sclerosing encapsulating peritonitis: a case report

    Energy Technology Data Exchange (ETDEWEB)

    Candido, Paula de Castro Menezes; Werner, Andrea de Freitas; Pereira, Izabela Machado Flores; Matos, Breno Assuncao; Pfeilsticker, Rudolf Moreira; Silva Filho, Raul, E-mail: paulacmcandido@yahoo.com.br [Hospital Felicio Rocho, Belo Horizonte, MG (Brazil)

    2015-01-15

    Sclerosing encapsulating peritonitis, a rare cause of bowel obstruction, was described as a complication associated with peritoneal dialysis which is much feared because of its severity. The authors report a case where radiological findings in association with clinical symptoms have allowed for a noninvasive diagnosis of sclerosing encapsulating peritonitis, emphasizing the high sensitivity and specificity of computed tomography to demonstrate the characteristic findings of such a condition. (author)

  12. FEM Simulation of Influence of Protective Encapsulation on MEMS Pressure Sensor

    DEFF Research Database (Denmark)

    Yao, Qingshan; Janting, Jakob; Branebjerg, Jens

    2003-01-01

    The objective of the work is to evaluate the feasibility of packaging a MEMS silicon pressure sensor by using either a polymer encapsulation or a combination of a polymer encapsulation and a metallic protection Membrane (fig. 1). The potential application of the protected sensor is for harsh...... environments. Several steps of simulation are carried out:1) Comparisons of the sensitivities are made among the non-encapsulated silicon sensor, the polymer encapsulated and polymer with metal encapsulated sensor. This is for evaluating whether the encapsulating materials reduce the pressure sensitivity...... whether the metallic membrane / coating will peel off when applying the maximum pressure, which is 4000 bar leading to high shear stress between the metallic membrane and the polymer encapsulation material.3) Thermal calculations are made to evaluate the influence of the environment on the packaged sensor...

  13. A simple encapsulation method for organic optoelectronic devices

    International Nuclear Information System (INIS)

    Sun Qian-Qian; An Qiao-Shi; Zhang Fu-Jun

    2014-01-01

    The performances of organic optoelectronic devices, such as organic light emitting diodes and polymer solar cells, have rapidly improved in the past decade. The stability of an organic optoelectronic device has become a key problem for further development. In this paper, we report one simple encapsulation method for organic optoelectronic devices with a parafilm, based on ternary polymer solar cells (PSCs). The power conversion efficiencies (PCE) of PSCs with and without encapsulation decrease from 2.93% to 2.17% and from 2.87% to 1.16% after 168-hours of degradation under an ambient environment, respectively. The stability of PSCs could be enhanced by encapsulation with a parafilm. The encapsulation method is a competitive choice for organic optoelectronic devices, owing to its low cost and compatibility with flexible devices. (atomic and molecular physics)

  14. A quantitative method for photovoltaic encapsulation system optimization

    Science.gov (United States)

    Garcia, A., III; Minning, C. P.; Cuddihy, E. F.

    1981-01-01

    It is pointed out that the design of encapsulation systems for flat plate photovoltaic modules requires the fulfillment of conflicting design requirements. An investigation was conducted with the objective to find an approach which will make it possible to determine a system with optimum characteristics. The results of the thermal, optical, structural, and electrical isolation analyses performed in the investigation indicate the major factors in the design of terrestrial photovoltaic modules. For defect-free materials, minimum encapsulation thicknesses are determined primarily by structural considerations. Cell temperature is not strongly affected by encapsulant thickness or thermal conductivity. The emissivity of module surfaces exerts a significant influence on cell temperature. Encapsulants should be elastomeric, and ribs are required on substrate modules. Aluminum is unsuitable as a substrate material. Antireflection coating is required on cell surfaces.

  15. Process engineering of high voltage alginate encapsulation of mesenchymal stem cells

    International Nuclear Information System (INIS)

    Gryshkov, Oleksandr; Pogozhykh, Denys; Zernetsch, Holger; Hofmann, Nicola; Mueller, Thomas; Glasmacher, Birgit

    2014-01-01

    Encapsulation of stem cells in alginate beads is promising as a sophisticated drug delivery system in treatment of a wide range of acute and chronic diseases. However, common use of air flow encapsulation of cells in alginate beads fails to produce beads with narrow size distribution, intact spherical structure and controllable sizes that can be scaled up. Here we show that high voltage encapsulation (≥ 15 kV) can be used to reproducibly generate spherical alginate beads (200–400 μm) with narrow size distribution (± 5–7%) in a controlled manner under optimized process parameters. Flow rate of alginate solution ranged from 0.5 to 10 ml/h allowed producing alginate beads with a size of 320 and 350 μm respectively, suggesting that this approach can be scaled up. Moreover, we found that applied voltages (15–25 kV) did not alter the viability and proliferation of encapsulated mesenchymal stem cells post-encapsulation and cryopreservation as compared to air flow. We are the first who employed a comparative analysis of electro-spraying and air flow encapsulation to study the effect of high voltage on alginate encapsulated cells. This report provides background in application of high voltage to encapsulate living cells for further medical purposes. Long-term comparison and work on alginate–cell interaction within these structures will be forthcoming. - Highlights: • High voltage alginate encapsulation of mesenchymal stem cells (MSCs) was designed. • Reproducible and spherical alginate beads were generated via high voltage. • Air flow encapsulation was utilized as a comparative approach to high voltage. • High voltage did not alter the viability and proliferation of encapsulated MSCs. • High voltage encapsulation can be scaled up and applied in cell-based therapy

  16. Production and characterization of nanocapsules encapsulated linalool by ionic gelation method using chitosan as wall material

    Directory of Open Access Journals (Sweden)

    Zuobing XIAO

    Full Text Available Abstract Linalool has been extensively applied in various fields, such as flavoring agent, perfumes, cosmetics and medical science. However, linalool is unstable, volatile and readily oxidizable. A sensitive substance can be encapsulated in a capsule, so encapsulation technology can solve these problems. In this paper, linalool-loaded nanocapsules (Lin-nanocapsules were prepared via the ionic gelation method and Lin-nanocapsules were characterized. The results of Fourier transformation infrared spectroscopy (FTIR showed that linalool was successfully encapsulated in the wall materials. Scanning electron microscopy (SEM results demonstrated that the shapes of Lin-nanocapsules, with smooth surfaces, were nearly spherical. Lin-nanocapsule average particle size was 352 nm and its polydispersity index (PDI was proved to be 0.214 by the results of dynamic light scattering (DLC. Thermogravimetric results indicated that linalool loading capacity (LC was 15.17%, and encapsulation could decrease linalool release and increase linalool retaining time under the high temperature. Oscillatory shear and steady-state shear measurements of Lin-nanocapsule emulsions were systematically investigated. The results of steady-state shear showed that Lin-nanocapsule emulsion, which was Newtonian only for high shear rate, was non-Newtonian. It was proved by oscillatory shear that when oscillation frequency changed from low to high, Lin-nanocapsules emulsion changed from viscous into elastic.

  17. Development of DBD plasma actuators: The double encapsulated electrode

    Science.gov (United States)

    Erfani, Rasool; Zare-Behtash, Hossein; Hale, Craig; Kontis, Konstantinos

    2015-04-01

    Plasma actuators are electrical devices that generate a wall bounded jet without the use of any moving parts. For aerodynamic applications they can be used as flow control devices to delay separation and augment lift on a wing. The standard plasma actuator consists of a single encapsulated (ground) electrode. The aim of this project is to investigate the effect of varying the number and distribution of encapsulated electrodes in the dielectric layer. Utilising a transformer cascade, a variety of input voltages are studied for their effect. In the quiescent environment of a Faraday cage the velocity flow field is recorded using particle image velocimetry. Through understanding of the mechanisms involved in producing the wall jet and the importance of the encapsulated electrode a novel actuator design is proposed. The actuator design distributes the encapsulated electrode throughout the dielectric layer. The experiments have shown that actuators with a shallow initial encapsulated electrode induce velocities greater than the baseline case at the same voltage. Actuators with a deep initial encapsulated electrode are able to induce the highest velocities as they can operate at higher voltages without breakdown of the dielectric.

  18. Activity of encapsulated Lactobacillus bulgaricus in alginate-whey protein microspheres

    Directory of Open Access Journals (Sweden)

    Meng-Yan Chen

    2014-10-01

    Full Text Available In this work, alginate-whey protein was used as wall materials for encapsulating Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus. The characteristics of encapsulated and free L. bulgaricus showed that the free L. bulgaricus lost viability after 1 min exposure to simulated gastric fluid (SGF at pH 2.0 and 2.5. However, the viability of encapsulated L. bulgaricus did not decrease in SGF at pH 2.5 for 2 h incubation. The viable numbers of encapsulated L. bulgaricus decreased less than 1.0 log unit for 2 h incubation in SGF at pH 2.0. For bile stability, only 1.2 log units and 2.0 log units viability of the encapsulated L. bulgaricus was lost in 1 and 2% bile for 1 h exposure, respectively, compared with no survival of free L. bulgaricus under the same conditions. Encapsulated L. bulgaricus was completely released from the microspheres in simulated intestinal fluid (SIF, pH 6.8 in 3 h. The viability of the encapsulated L. bulgaricus retained more 8.0 log CFU/g after stored at 4°C for four weeks. However, for free L. bulgaricus, only around 3.0 log CFU/mL was found at the same storage conditions. Results showed that the encapsulation could improve the stability of L. bulgaricus.

  19. Low-cost encapsulation materials for terrestrial solar cell modules

    Science.gov (United States)

    Cuddihy, E. F.; Baum, B.; Willis, P.

    1979-01-01

    The paper presents the findings of material surveys intended to identify low cost materials which could be functional as encapsulants (by 1986) for terrestrial solar cell modules. Economic analyses have indicated that in order to meet the low cost goal of $2.70 per sq m, some or all of the following material technologies must be developed or advanced: (1) UV screening outer covers; (2) elastomeric acrylics; (3) weatherproofing and waterproofing of structural wood and paper products; (4) transparent UV stabilizers for the UV-sensitive transparent pottants; and (5) cost-effective utilization of silicone and fluorocarbon materials.

  20. Estimating service lifetimes of a polymer encapsulant for photovoltaic modules from accelerated testing

    Energy Technology Data Exchange (ETDEWEB)

    Czanderna, A.W.; Pern, F.J. [National Renewable Energy Lab., Golden, CO (United States)

    1996-05-01

    In this paper, most of the emphasis is on A9918 ethylene vinyl acetate (EVA) used commercially as the pottant for encapsulating photovoltaic (PV) modules, in which the efficiencies in field-deployed modules have been reduced by 10-70% in 4-12 years. Yet, projections were made by several different research groups in the 1980s that the EVA lifetime could range from 2-100 years. The authors (1) elucidate the complexity of the encapsulation problem, (2) indicate the performance losses reported for PV systems deployed since 1981, (3) critically assess the service lifetime predictions for EVA as a PV pottant based on studies by others for which they review the inherent errors in their assumptions about the Arrhenius relation, (4) show how degradation of minimodules in laboratory experiments that simulate reality can produce efficiency losses comparable to those in field-degraded PV modules reported in the literature, and (5) outline an acceptable methodology for making a service lifetime prediction of the polymer encapsulant, including the essential need for relating accelerated lifetime testing to real-time testing with a sufficient number of samples.

  1. Personnel protective equipment total-encapsulating suit decontamination study using shower systems

    International Nuclear Information System (INIS)

    Menkhaus, D.E.

    1991-01-01

    This report documents an experimental evaluation, conducted at the Idaho National Engineering Laboratory, of a shower-based decontamination station for personnel wearing a Level A, total- encapsulating, chemical-protective suit. The decontamination station is used by personnel when egressing a dry, dusty environment contaminated with transuranic radionuclides. This system has the potential to minimize the risk of spreading the contaminants to clean areas. Two types of shower systems were evaluated, a drench shower and a multi-nozzle shower. A total-encapsulating suit, worn by personnel. was contaminated with soil containing 239 Pu. Pre- shower and post-shower contamination samples were collected and visual observations were made to evaluate the ability of the shower system to remove the contaminated dust and to obtain baseline data useful in designing a shower-based personnel decontamination system. 12 figs., 7 tabs

  2. Encapsulation and delivery of food ingredients using starch based systems.

    Science.gov (United States)

    Zhu, Fan

    2017-08-15

    Functional ingredients can be encapsulated by various wall materials for controlled release in food and digestion systems. Starch, as one of the most abundant natural carbohydrate polymers, is non-allergenic, GRAS, and cheap. There has been increasing interest of using starch in native and modified forms to encapsulate food ingredients such as flavours, lipids, polyphenols, carotenoids, vitamins, enzymes, and probiotics. Starches from various botanical sources in granular or amorphous forms are modified by chemical, physical, and/or enzymatic means to obtain the desired properties for targeted encapsulation. Other wall materials are also employed in combination with starch to facilitate some types of encapsulation. Various methods of crafting the starch-based encapsulation such as electrospinning, spray drying, antisolvent, amylose inclusion complexation, and nano-emulsification are introduced in this mini-review. The physicochemical and structural properties of the particles are described. The encapsulation systems can positively influence the controlled release of food ingredients in food and nutritional applications. Copyright © 2017 Elsevier Ltd. All rights reserved.

  3. Antidiabetic Activity from Gallic Acid Encapsulated Nanochitosan

    Science.gov (United States)

    Purbowatiningrum; Ngadiwiyana; Ismiyarto; Fachriyah, E.; Eviana, I.; Eldiana, O.; Amaliyah, N.; Sektianingrum, A. N.

    2017-02-01

    Diabetes mellitus (DM) has become a health problem in the world because it causes death. One of the phenolic compounds that have antidiabetic activity is gallic acid. However, the use of this compound still provides unsatisfactory results due to its degradation during the absorption process. The solution offered to solve the problem is by encapsulated it within chitosan nanoparticles that serve to protect the bioactive compound from degradation, increases of solubility and delivery of a bioactive compound to the target site by using freeze-drying technique. The result of chitosan nanoparticle’s Scanning Electron Microscopy (SEM) showed that chitosan nanoparticle’s size is uniform and it is smaller than chitosan. The value of encapsulation efficiency (EE) of gallic acid which encapsulated within chitosan nanoparticles is about 50.76%. Inhibition test result showed that gallic acid-chitosan nanoparticles at 50 ppm could inhibite α-glucosidase activity in 28.87% with 54.94 in IC50. So it can be concluded that gallic acid can be encapsulated in nanoparticles of chitosan and proved that it could inhibit α-glucosidase.

  4. The influence of size on the toxicity of an encapsulated pesticide: a comparison of micron- and nano-sized capsules.

    Science.gov (United States)

    Meredith, Alicea N; Harper, Bryan; Harper, Stacey L

    2016-01-01

    Encapsulation technology involves entrapping a chemical active ingredient (a.i.) inside a hollow polymeric shell and has been applied to commercial pesticide manufacturing for years to produce capsule suspension (CS) formulations with average particle sizes in the micron-scale. The few literature sources that investigate the environmental fate and toxicity to non-target organisms of encapsulated commercially available pesticide products with regard to capsule size report on average sizes between 20 and 50 μm. Here, we have identified a CS formulation with an average capsule size of approximately 2 μm with some capsules extending into the nanometer scale (~200 nm). Determining how carrier size influences toxicity is important to understanding if current pesticide risk assessments are sufficient to protect against products that incorporate encapsulation technology. Here, a commercial pyrethroid CS pesticide with lambda-cyhalothrin (λ-Cy) as the a.i. was separated into two suspensions, a fraction consisting of nano-sized capsules (~250 nm) and a fraction of micron-sized capsules (~2200 nm) in order to investigate the influence of capsule size on toxicity to embryonic zebrafish, Danio rerio. Toxicity was evaluated 24h after exposure to equivalent amounts of a.i. by the presence and severity of pyrethroid-specific tremors, 14 sublethal developmental impacts and mortality. Fish exposed to greater than 20 μg a.i. L(-1) technical λ-Cy or formulated product experienced curvature of the body axis, pericardial edema, craniofacial malformations, and mortality. Exposure to the unfractionated formulation, micro fraction, nano fraction and technical a.i. resulted in no significant differences in the occurrence of sublethal impacts or mortality; however, the technical a.i. exposure resulted in significantly less fish experiencing tremors and shorter tremors compared to any of the formulated product exposures. This suggests that the capsule size does not influence the toxic

  5. Protein encapsulation via porous CaCO3 microparticles templating.

    Science.gov (United States)

    Volodkin, Dmitry V; Larionova, Natalia I; Sukhorukov, Gleb B

    2004-01-01

    Porous microparticles of calcium carbonate with an average diameter of 4.75 microm were prepared and used for protein encapsulation in polymer-filled microcapsules by means of electrostatic layer-by-layer assembly (ELbL). Loading of macromolecules in porous CaCO3 particles is affected by their molecular weight due to diffusion-limited permeation inside the particles and also by the affinity to the carbonate surface. Adsorption of various proteins and dextran was examined as a function of pH and was found to be dependent both on the charge of the microparticles and macromolecules. The electrostatic effect was shown to govern this interaction. This paper discusses the factors which can influence the adsorption capacity of proteins. A new way of protein encapsulation in polyelectrolyte microcapsules is proposed exploiting the porous, biocompatible, and decomposable microparticles from CaCO3. It consists of protein adsorption in the pores of the microparticles followed by ELbL of oppositely charged polyelectrolytes and further core dissolution. This resulted in formation of polyelectrolyte-filled capsules with protein incorporated in interpenetrating polyelectrolyte network. The properties of CaCO3 microparticles and capsules prepared were characterized by scanning electron microscopy, microelectrophoresis, and confocal laser scanning microscopy. Lactalbumin was encapsulated by means of the proposed technique yielding a content of 0.6 pg protein per microcapsule. Horseradish peroxidase saves 37% of activity after encapsulation. However, the thermostability of the enzyme was improved by encapsulation. The results demonstrate that porous CaCO3 microparticles can be applied as microtemplates for encapsulation of proteins into polyelectrolyte capsules at neutral pH as an optimal medium for a variety of bioactive material, which can also be encapsulated by the proposed method. Microcapsules filled with encapsulated material may find applications in the field of

  6. Mineral assemblage transformation of a metakaolin-based waste form after geopolymer encapsulation

    Energy Technology Data Exchange (ETDEWEB)

    Williams, Benjamin D., E-mail: Benjamin.Williams@pnnl.gov [Pacific Northwest National Laboratory, PO Box 999, MSIN P7-54, Richland, WA 99352 (United States); Neeway, James J., E-mail: James.Neeway@pnnl.gov [Pacific Northwest National Laboratory, PO Box 999, MSIN P7-54, Richland, WA 99352 (United States); Snyder, Michelle M.V., E-mail: Michelle.ValentaSnyder@pnnl.gov [Pacific Northwest National Laboratory, PO Box 999, MSIN P7-54, Richland, WA 99352 (United States); Bowden, Mark E., E-mail: Mark.Bowden@pnnl.gov [Pacific Northwest National Laboratory, PO Box 999, MSIN P7-54, Richland, WA 99352 (United States); Amonette, James E., E-mail: Jim.Amonette@pnnl.gov [Pacific Northwest National Laboratory, PO Box 999, MSIN P7-54, Richland, WA 99352 (United States); Arey, Bruce W., E-mail: Bruce.Arey@pnnl.gov [Pacific Northwest National Laboratory, PO Box 999, MSIN P7-54, Richland, WA 99352 (United States); Pierce, Eric M., E-mail: pierceem@ornl.gov [Oak Ridge National Laboratory, PO Box 2008, MS-6035, Room 372, Oak Ridge, TN 37831 (United States); Brown, Christopher F., E-mail: Christopher.Brown@pnnl.gov [Pacific Northwest National Laboratory, PO Box 999, MSIN P7-54, Richland, WA 99352 (United States); Qafoku, Nikolla P., E-mail: Nik.Qafoku@pnnl.gov [Pacific Northwest National Laboratory, PO Box 999, MSIN P7-54, Richland, WA 99352 (United States)

    2016-05-15

    Mitigation of hazardous and radioactive waste can be improved through conversion of existing waste to a more chemically stable and physically robust waste form. One option for waste conversion is the fluidized bed steam reforming (FBSR) process. The resulting FBSR granular material was encapsulated in a geopolymer matrix referred to here as Geo-7. This provides mechanical strength for ease in transport and disposal. However, it is necessary to understand the phase assemblage evolution as a result of geopolymer encapsulation. In this study, we examine the mineral assemblages formed during the synthesis of the multiphase ceramic waste form. The FBSR granular samples were created from waste simulant that was chemically adjusted to resemble Hanford tank waste. Another set of samples was created using Savannah River Site Tank 50 waste simulant in order to mimic a blend of waste collected from 68 Hanford tank. Waste form performance tests were conducted using the product consistency test (PCT), the Toxicity Characteristic Leaching Procedure (TCLP), and the single-pass flow-through (SPFT) test. X-ray diffraction analyses revealed the structure of a previously unreported NAS phase and indicate that monolith creation may lead to a reduction in crystallinity as compared to the primary FBSR granular product. - Highlights: • Simulated Hanford waste was treated by the Fluidized Bed Steam Reformer (FBSR) process. • The FBSR granular product was encapsulated in a geopolymer monolith. • Leach tests were performed to examine waste form performance. • XRD revealed the structure of a previously unreported sodium aluminosilicate phase. • Monolithing of granular waste forms may lead to a reduction in crystallinity.

  7. Electrospun Phospholipid Fibers as Micro-Encapsulation and Antioxidant Matrices.

    Science.gov (United States)

    Shekarforoush, Elhamalsadat; Mendes, Ana C; Baj, Vanessa; Beeren, Sophie R; Chronakis, Ioannis S

    2017-10-17

    Electrospun phospholipid (asolectin) microfibers were investigated as antioxidants and encapsulation matrices for curcumin and vanillin. These phospholipid microfibers exhibited antioxidant properties which increased after the encapsulation of both curcumin and vanillin. The total antioxidant capacity (TAC) and the total phenolic content (TPC) of curcumin/phospholipid and vanillin/phospholipid microfibers remained stable over time at different temperatures (refrigerated, ambient) and pressures (vacuum, ambient). ¹H-NMR confirmed the chemical stability of both encapsulated curcumin and vanillin within phospholipid fibers. Release studies in aqueous media revealed that the phenolic bioactives were released mainly due to swelling of the phospholipid fiber matrix over time. The above studies confirm the efficacy of electrospun phospholipid microfibers as encapsulation and antioxidant systems.

  8. Electrospun Phospholipid Fibers as Micro-Encapsulation and Antioxidant Matrices

    Directory of Open Access Journals (Sweden)

    Elhamalsadat Shekarforoush

    2017-10-01

    Full Text Available Electrospun phospholipid (asolectin microfibers were investigated as antioxidants and encapsulation matrices for curcumin and vanillin. These phospholipid microfibers exhibited antioxidant properties which increased after the encapsulation of both curcumin and vanillin. The total antioxidant capacity (TAC and the total phenolic content (TPC of curcumin/phospholipid and vanillin/phospholipid microfibers remained stable over time at different temperatures (refrigerated, ambient and pressures (vacuum, ambient. 1H-NMR confirmed the chemical stability of both encapsulated curcumin and vanillin within phospholipid fibers. Release studies in aqueous media revealed that the phenolic bioactives were released mainly due to swelling of the phospholipid fiber matrix over time. The above studies confirm the efficacy of electrospun phospholipid microfibers as encapsulation and antioxidant systems.

  9. Strain screening, fermentation, separation, and encapsulation for production of nattokinase functional food.

    Science.gov (United States)

    Wei, Xuetuan; Luo, Mingfang; Xie, Yuchun; Yang, Liangrong; Li, Haojian; Xu, Lin; Liu, Huizhou

    2012-12-01

    This study presents a novel and integrated preparation technology for nattokinase functional food, including strain screening, fermentation, separation, and encapsulation. To rapidly screen a nattokinase-productive strain, PCR-based screening method was combined with fibrinolytic activity-based method, and a high productive strain, Bacillus subtilis LSSE-22, was isolated from Chinese soybean paste. Reduction of poly-γ-glutamic acid (γ-PGA) concentration may contribute to separation of nattokinase and reduction of late-onset anaphylaxis risk. Chickpeas were confirmed as the favorable substrate for enhancement of nattokinase production and reduction of γ-PGA yield. Using cracked chickpeas, the nattokinase activity reached 356.25 ± 17.18 FU/g (dry weight), which is much higher than previous reports. To further reduce γ-PGA concentration, ethanol fractional extraction and precipitation were applied for separation of nattokinase. By extraction with 50 % and precipitation with 75 % ethanol solution, 4,000.58 ± 192.98 FU/g of nattokinase powders were obtained, and the activity recovery reached 89 ± 1 %, while γ-PGA recovery was reduced to 21 ± 2 %. To improve the nattokinase stability at acidic pH condition, the nattokinase powders were encapsulated, and then coated with methacrylic acid-ethyl acrylate copolymer. After encapsulation, the nattokinase was protected from being denatured under various acid conditions, and pH-responsible controlled release at simulated intestinal fluid was realized.

  10. Effects of Different End-Point Cooking Temperatures on the Efficiency of Encapsulated Phosphates on Lipid Oxidation Inhibition in Ground Meat.

    Science.gov (United States)

    Kılıç, B; Şimşek, A; Claus, J R; Atılgan, E; Aktaş, N

    2015-10-01

    Effects of 0.5% encapsulated (e) phosphates (sodium tripolyphosphate, STP; sodium hexametaphosphate, HMP; sodium pyrophosphate, SPP) on lipid oxidation during storage (0, 1, and 7 d) of ground meat (chicken, beef) after being cooked to 3 end-point cooking temperatures (EPCT; 71, 74, and 77 °C) were evaluated. The use of STP or eSTP resulted in lower (P cooking loss (CL) compared to encapsulated or unencapsulated forms of HMP and SPP. Increasing EPCT led to a significant increase in CL (P chicken compared to 74 and 71 °C (P chicken samples (P < 0.05). Findings suggest that encapsulated phosphates can be a strategy to inhibit lipid oxidation for meat industry and the efficiency of encapsulated phosphates on lipid oxidation inhibition can be enhanced by lowering EPCT. © 2015 Institute of Food Technologists®

  11. Comparative behavior between sunscreens based on free or encapsulated UV filters in term of skin penetration, retention and photo-stability.

    Science.gov (United States)

    Cozzi, Arianna C; Perugini, Paola; Gourion-Arsiquaud, Samuel

    2018-06-03

    The growing incidence of photodamaging effects caused by UV radiation (e.g. sunburn, skin cancer) has increased the attention from health authorities which recommend the topical application of sunscreens to prevent these skin damages. The economic stakes for those companies involved in this international market are to develop new UV filters and innovative technologies to provide the most efficient, flexible and robust sunscreen products. Today the development of innovative and competitive sunscreen products is a complex formulation challenge. Indeed, the current sunscreens must protect against skin damages, while also being safe for the skin and being sensory and visually pleasant for the customers when applied on the skin. Organic UV filters, while proposing great advantages, also present the risk to penetrate the stratum corneum and diffuse into underlying structures with unknown consequences; moreover, their photo-stability are noted thorny outcomes in sunscreen development and subsequent performance. In recent years, the evaluation of the interaction between skin and sunscreen in terms of penetration after topical application has been considered from European authority but still its testing as their photo-stability assessment are not mandatory in most countries. This study, based on in-vitro approaches, was performed to evaluate and compare the retention and the penetration of organic UV filters in free or encapsulated form inside the skin as well as their respective photo-stability. Sunscreen formulation with a combination of Avobenzone and Octocrylene in "free form" and a formulation using the same UV filters but encapsulated in a sol-gel silica capsule, were analyzed and compared by FTIR Imaging Spectroscopy. Tape stripping method was used to investigate the penetration of these UV filters inside the stratum corneum. Their photo-stabilities were evaluated by spectroscopic measurements (FTIR, UV/Vis) and standard measurements were calculated: AUC (Area Under

  12. K Basins fuel encapsulation and storage hazard categorization

    International Nuclear Information System (INIS)

    Porten, D.R.

    1994-12-01

    This document establishes the initial hazard categorization for K-Basin fuel encapsulation and storage in the 100 K Area of the Hanford site. The Hazard Categorization for K-Basins addresses the potential for release of radioactive and non-radioactive hazardous material located in the K-Basins and their supporting facilities. The Hazard Categorization covers the hazards associated with normal K-Basin fuel storage and handling operations, fuel encapsulation, sludge encapsulation, and canister clean-up and disposal. The criteria categorizes a facility based on total curies per radionuclide located in the facility. Tables 5-3 and 5-4 display the results in section 5.0. In accordance with DOE-STD-1027 and the analysis provided in section 5.0, the K East Basin fuel encapsulation and storage activity and the K West Basin storage are classified as a open-quotes Category 2close quotes Facility

  13. Modeling Encapsulated Microbubble Dynamics at High Pressure Amplitudes

    Science.gov (United States)

    Heyse, Jan F.; Bose, Sanjeeb; Iaccarino, Gianluca

    2017-11-01

    Encapsulated microbubbles are commonly used in ultrasound contrast imaging and are of growing interest in therapeutic applications where local cavitation creates temporary perforations in cell membranes allowing for enhanced drug delivery. Clinically used microbubbles are encapsulated by a shell commonly consisting of protein, polymer, or phospholipid; the response of these bubbles to externally imposed ultrasound waves is sensitive to the compressibility of the encapsulating shell. Existing models approximate the shell compressibility via an effective surface tension (Marmottant et al. 2005). We present simulations of microbubbles subjected to high amplitude ultrasound waves (on the order of 106 Pa) and compare the results with the experimental measurements of Helfield et al. (2016). Analysis of critical points (corresponding to maximum and minimum expansion) in the governing Rayleigh-Plesset equation is used to make estimates of the parameters used to characterize the effective surface tension of the encapsulating shell. Stanford Graduate Fellowship.

  14. Study of the erythropoiesis activity of nano-encapsulated forms of erythropoietin

    Directory of Open Access Journals (Sweden)

    Zhanagul Khasenbekova

    2014-01-01

    Full Text Available Introduction: The recombinant human erythropoietin (rhEPO is used in the treatment of anemia. In order to improve its pharmacokinetic properties, nanoparticles of biodegradable polymers of natural or synthetic origin were used. The aim of this study was to investigate the effect of new nano-encapsulated forms of recombinant human erythropoietin for oral use on the erythropoiesis in the cyclophosphamide immunosuppression model. Material and methods: The CHOpE immortalized cells culture (a primary producer of rhEPO "Vector" in Russia was used. The following biodegradable polymers were chosen: 0.05% and 0.005% carbopol, 0.05% and 0.005% kollidon, and 0.05% and 0.005% pectin. Immunosuppression was obtained by a single dose of i.p. injection of cyclophosphamide (250 mg/kg in white mice (18-20 g. During the next 5 days, the nano-encapsulated erythropoietin (100 ED/mouse was administered orally to each mouse. After 5 and 10 days, the cell count of the number of blood reticulocytes and the myelogram of bone marrow were performed. The control group of mice received injections of Eprex. Results: On the 5th day of the experiment, the highest level of reticulocyte was observed in the samples of erythropoietin with kollidon (0.05% and pectin (0.005% nanoparticles. On the 10th day, the highest activity was observed in the samples of erythropoietin substance with pectin at 0.05% and 0.005% concentrations. The levels of reticulocytes in these groups reached 13.53% and 14.55%, respectively. The results of the myelogram during immunosuppression showed some activity of erythropoietin in conjunction with both concentrations of pectin when a two-fold increase in the number of erythroblasts was observed on the 5th day. High degrees of erythrokaryocytes in the state of mitosis were observed in the 0.05% pectin samples. Similar results were observed in equivalent groups of control animals on the 10th day of the experiment, which is compatible with the data on Eprex

  15. Electrospun Phospholipid Fibers as Micro-Encapsulation and Antioxidant Matrices

    DEFF Research Database (Denmark)

    Shekarforoush, Elhamalsadat; Mendes, Ana Carina Loureiro; Baj, Vanessa

    2017-01-01

    Electrospun phospholipid (asolectin) microfibers were investigated as antioxidants and encapsulation matrices for curcumin and vanillin. These phospholipid microfibers exhibited antioxidant properties which increased after the encapsulation of both curcumin and vanillin. The total antioxidant...... capacity (TAC) and the total phenolic content (TPC) of curcumin/phospholipid and vanillin/phospholipid microfibers remained stable over time at different temperatures (refrigerated, ambient) and pressures (vacuum, ambient). ¹H-NMR confirmed the chemical stability of both encapsulated curcumin and vanillin...

  16. High Throughput Single-cell and Multiple-cell Micro-encapsulation

    OpenAIRE

    Lagus, Todd P.; Edd, Jon F.

    2012-01-01

    Microfluidic encapsulation methods have been previously utilized to capture cells in picoliter-scale aqueous, monodisperse drops, providing confinement from a bulk fluid environment with applications in high throughput screening, cytometry, and mass spectrometry. We describe a method to not only encapsulate single cells, but to repeatedly capture a set number of cells (here we demonstrate one- and two-cell encapsulation) to study both isolation and the interactions between cells in groups of ...

  17. High voltage photo-switch package module having encapsulation with profiled metallized concavities

    Science.gov (United States)

    Sullivan, James S; Sanders, David M; Hawkins, Steven A; Sampayan, Stephen A

    2015-05-05

    A photo-conductive switch package module having a photo-conductive substrate or wafer with opposing electrode-interface surfaces metalized with first metallic layers formed thereon, and encapsulated with a dielectric encapsulation material such as for example epoxy. The first metallic layers are exposed through the encapsulation via encapsulation concavities which have a known contour profile, such as a Rogowski edge profile. Second metallic layers are then formed to line the concavities and come in contact with the first metal layer, to form profiled and metalized encapsulation concavities which mitigate enhancement points at the edges of electrodes matingly seated in the concavities. One or more optical waveguides may also be bonded to the substrate for coupling light into the photo-conductive wafer, with the encapsulation also encapsulating the waveguides.

  18. Comparative assessment of plasmid DNA delivery by encapsulation ...

    African Journals Online (AJOL)

    Purpose: To compare the gene delivery effectiveness of plasmid DNA (pDNA) encapsulated within poly (D,L-lactide-co-glycolide) (PLGA) nanoparticles with that adsorbed on PLGA nanoparticles. Methods: PLGA nanoparticles were prepared using solvent-evaporation method. To encapsulate pDNA within the particles, ...

  19. Preliminary safety evaluation of a commercial-scale krypton-85 encapsulation facility

    International Nuclear Information System (INIS)

    Christensen, A.B.; Tanner, J.E.; Knecht, D.A.

    1980-09-01

    This report demonstrates that a commercial-scale facility for encapsulating krypton-85 in zeolite-5A or glass at a 2000 MTHM per year nuclear fuel reprocessing plant can be designed to contain fragments and the 340 to 850 kCi krypton-85 inventory from an assumed catastrophic failure of the high pressure vessel. The vessel failure was assumed as a worst case and was not based on a detailed design evaluation or operating experience. The process design is based on existing commercial hot isostatic pressing technology operated at up to 40 times the scale required for krypton encapsulation. From the calculated process gas inventory in the pressure vessel and vessel design, the explosive energy of 8.4 kg TNT and vessel plug and fragment velocities were calculated. The facility Containment Cell housing the high pressure vessel was designed to contain the gases, fragments, and the shock wave energy calculated for vessel failure. The Access Cell located directly above the Containment Cell was designed to be a tertiary confinement of krypton-85, should the access hatch be breached

  20. Enhancement of survival of alginate-encapsulated Lactobacillus casei NCDC 298.

    Science.gov (United States)

    Mandal, Surajit; Hati, Subrota; Puniya, Anil Kumar; Khamrui, Kaushik; Singh, Kishan

    2014-08-01

    Micro-encapsulation of hydrocolloids improves the survival of sensitive probiotic bacteria in the harsh conditions that prevail in foods and during gastrointestinal passage by segregating them from environments. Incorporation of additives in encapsulating hydrocolloids and coatings of microcapsules further improves the survival of the probiotics. In this study, the effect of incorporation of resistant-maize starch in alginate for micro-encapsulation and coating of microcapsules with poly-l-lysine, stearic acid and bees wax on the survival of encapsulated Lactobacillus casei NCDC 298 at pH 1.5, 2% high bile salt, 65 °C for 20 min and release of viable lactobacilli cells from the capsule matrix in simulated aqueous solutions of colonic pH were assessed. Addition of resistant maize starch (2%) improved the survival of encapsulated L. casei NCDC 298. Coating of microcapsules with poly-L-lysine did not further improve the protection of encapsulated cells from the harsh conditions; however, bees wax and stearic acid (2%) improved the survival under similar conditions. Incorporation of maize starch (2%) in alginate followed by coating of beads with stearic acid (2%) led to better protection and complete release of entrapped lactobacilli in simulated colonic pH solution was observed. Additional treatments improve the survival of alginate-encapsulated lactobacilli cells without hindering the release of active cells from the capsule matrix and hence, the resulting encapsulated probiotics can be exploited in the development of probiotic functional foods with better survival of sensitive probiotic organisms. © 2013 Society of Chemical Industry.

  1. Notice of construction for the 105 KE encapsulation activity

    International Nuclear Information System (INIS)

    1993-03-01

    This is a Notice of Construction for the 105-KE Basin Fuel Encapsulation Activity. This Notice of Construction is being submitted to the State of Washington Department of Health pursuant to the Washington Administrative Code, 246-247, ''Radiation Protection--Air Emissions,'' as amended. The encapsulation activity will consist of all of the activities described in Section 1.3 as necessary to complete encapsulation of the fuel elements and sludge contained in the 105-KE Basin. The encapsulation activity will be carried out on the 105-KE Basin floor under a minimum of 3 m (10 ft) of water. The encapsulation activity.includes emptying irradiated fuel elements from the existing canisters stored in the 105-KE Basin, packaging.these fuel elements in new canisters, packaging sludge from previous fuel inventories and the current inventory in new canisters, capping these canisters of fuel elements and sludge, and returning the new canisters to the storage racks in the basin. The empty canisters will be cleaned and crushed underwater. Packaging and disposal of the crushed canisters will take place above the water

  2. The application of ultrasonic techniques to the quality checking of encapsulated radioactive waste

    International Nuclear Information System (INIS)

    Wood, J.M.

    1985-03-01

    The work described in this report was in two parts. First, a literature survey was conducted to review the current practice of ultrasonic inspection of concrete. In particular, the relevance of each technique to the inspection of encapsulated radioactive waste was assessed. Secondly, a limited amount of experimental work was performed on samples of cementitious samples, using available commercial equipment. Conclusions are drawn from the study and experimental work and recommendations made for possible future programmes of work. (author)

  3. Durable crystalline Si photovoltaic modules based on silicone-sheet encapsulants

    Science.gov (United States)

    Hara, Kohjiro; Ohwada, Hiroto; Furihata, Tomoyoshi; Masuda, Atsushi

    2018-02-01

    Crystalline Si photovoltaic (PV) modules were fabricated with sheets of poly(dimethylsiloxane) (silicone) as an encapsulant. The long-term durability of the silicone-encapsulated PV modules was experimentally investigated. The silicone-based modules enhanced the long-term durability against potential-induced degradation (PID) and a damp-heat (DH) condition at 85 °C with 85% relative humidity (RH). In addition, we designed and fabricated substrate-type Si PV modules based on the silicone encapsulant and an Al-alloy plate as the substratum, which demonstrated high impact resistance and high incombustible performance. The high chemical stability, high volume resistivity, rubber-like elasticity, and incombustibility of the silicone encapsulant resulted in the high durability of the modules. Our results indicate that silicone is an attractive encapsulation material, as it improves the long-term durability of crystalline Si PV modules.

  4. Plasma-assisted atomic layer deposition of Al(2)O(3) and parylene C bi-layer encapsulation for chronic implantable electronics.

    Science.gov (United States)

    Xie, Xianzong; Rieth, Loren; Merugu, Srinivas; Tathireddy, Prashant; Solzbacher, Florian

    2012-08-27

    Encapsulation of biomedical implants with complex three dimensional geometries is one of the greatest challenges achieving long-term functionality and stability. This report presents an encapsulation scheme that combines Al(2)O(3) by atomic layer deposition with parylene C for implantable electronic systems. The Al(2)O(3)-parylene C bi-layer was used to encapsulate interdigitated electrodes, which were tested invitro by soak testing in phosphate buffered saline solution at body temperature (37 °C) and elevated temperatures (57 °C and 67 °C) for accelerated lifetime testing up to 5 months. Leakage current and electrochemical impedance spectroscopy were measured for evaluating the integrity and insulation performance of the coating. Leakage current was stably about 15 pA at 5 V dc, and impedance was constantly about 3.5 MΩ at 1 kHz by using electrochemical impedance spectroscopy for samples under 67 °C about 5 months (approximately equivalent to 40 months at 37 °C). Alumina and parylene coating lasted at least 3 times longer than parylene coated samples tested at 80 °C. The excellent insulation performance of the encapsulation shows its potential usefulness for chronic implants.

  5. Synthesis and Characterization of Encapsulated Nanosilica Particles with an Acrylic Copolymer by in Situ Emulsion Polymerization Using Thermoresponsive Nonionic Surfactant

    Directory of Open Access Journals (Sweden)

    Daryoosh Vashaee

    2013-08-01

    Full Text Available Nanocomposites of encapsulated silica nanoparticles were prepared by in situ emulsion polymerization of acrylate monomers. The synthesized material showed good uniformity and dispersion of the inorganic components in the base polymer, which enhances the properties of the nanocomposite material. A nonionic surfactant with lower critical solution temperature (LCST was used to encapsulate the silica nanoparticles in the acrylic copolymer matrix. This in situ method combined the surface modification and the encapsulation in a single pot, which greatly simplified the process compared with other conventional methods requiring separate processing steps. The morphology of the encapsulated nanosilica particles was investigated by dynamic light scattering (DLS and transmission electron microscopy (TEM, which confirmed the uniform distribution of the nanoparticles without any agglomerations. A neat copolymer was also prepared as a control sample. Both the neat copolymer and the prepared nanocomposite were characterized by Fourier transform infrared spectroscopy (FTIR, thermal gravimetric analyses (TGA, dynamic mechanical thermal analysis (DMTA and the flame resistance test. Due to the uniform dispersion of the non-agglomerated nanoparticles in the matrix of the polymer, TGA and flame resistance test results showed remarkably improved thermal stability. Furthermore, DMTA results demonstrated an enhanced storage modulus of the nanocomposite samples compared with that of the neat copolymer, indicating its superior mechanical properties.

  6. Polymer encapsulated dopaminergic cell lines as "alternative neural grafts".

    Science.gov (United States)

    Jaeger, C B; Greene, L A; Tresco, P A; Winn, S R; Aebischer, P

    1990-01-01

    Our preliminary findings (Jaeger et al., 1988; Aebischer et al., 1989; Tresco et al., 1989) and the studies in progress show that encapsulated dopaminergic cell lines survive enclosure within a semi-permeable membrane. The encapsulated cells remained viable for extended time periods when maintained in vitro. Moreover, encapsulated PC12 and T28 cells have the potential to survive following their implantation into the forebrain of rats. Cell lines are essentially "immortal" because they continue to divide indefinitely. This property allows perpetual "self-renewal" of a given cell population. However, the capacity of continuous uncontrolled cell division may also lead to tumor formation. This in fact is the case for unencapsulated PC12 cell implants placed into the brain of young Sprague Dawley rats (Jaeger, 1985). Cell line encapsulation has the potential to prevent tumor growth (Jaeger et al., 1988). Survival for 6 months in vitro suggests that encapsulation does not preclude long-term maintenance of an homogeneous cell line like PC12 cells. The presence of mitotic figures in the capsules further supports the likelihood of propagation and self renewal of the encapsulated population. Another significant property of cell lines is that they consist of a single, genetically homogeneous cell type. They do not require specific synaptic interactions for their survival. In the case of PC12 and T28 lines, the cells synthesize and release neurotransmitters. Our data show that PC12 and T28 cells continue to release dopamine spontaneously and to express specific transmitters and enzymes following encapsulation. Thus, cell lines such as these may constitute relatively simple "neural implants" exerting their function via humoral release.(ABSTRACT TRUNCATED AT 250 WORDS)

  7. Encapsulation with structured triglycerides

    Science.gov (United States)

    Lipids provide excellent materials to encapsulate bioactive compounds for food and pharmaceutical applications. Lipids are renewable, biodegradable, and easily modified to provide additional chemical functionality. The use of structured lipids that have been modified with photoactive properties are ...

  8. Characterisation of electrospun gelatine nanofibres encapsulated with Moringa oleifera bioactive extract.

    Science.gov (United States)

    Hani, Norziah M; Torkamani, Amir E; Azarian, Mohammad H; Mahmood, Kamil Wa; Ngalim, Siti Hawa

    2017-08-01

    Drumstick (Moringa oleifera) leaves have been used as a folk herbal medicine across many cultures since ancient times. This is most probably due to presence of phytochemicals possessing antioxidant properties, which could retard oxidative stress, and their degenerative effect. The current study deals with nanoencapsulation of Moringa oleifera (MO) leaf ethanolic extract within fish sourced gelatine matrix using electrospinning technique. The total phenolic and flavonoid content, radical scavenging (IC 50 ) and metal reducing properties were 67.0 ± 2.5 mg GAE g -1 sample 32.0 ± 0.5 mg QE g -1 extract, 0.08 ± 0.01 mg mL -1 and 510 ± 10 µmol eq Fe(II) g -1 extract, respectively. Morphological and spectroscopic analysis of the fibre mats confirmed successful nanoencapsulation of MO extract within defect free nanofibres via electrospinning process. The percentage encapsulation efficiency (EE) was between 80% and 85%. Furthermore, thermal stability of encapsulated fibres, especially at 3% and 5% of core loading content, was significantly improved. Toxicological analysis revealed that the extract in its original and encapsulated form was safe for oral consumption. Overall, the present study showed the potential of ambient temperature electrospinning process as a safe nanoencapsulation method, where MO extract retained its antioxidative capacities. © 2016 Society of Chemical Industry. © 2016 Society of Chemical Industry.

  9. Selective Co-Encapsulation Inside an M6 L4 Cage.

    Science.gov (United States)

    Leenders, Stefan H A M; Becker, René; Kumpulainen, Tatu; de Bruin, Bas; Sawada, Tomohisa; Kato, Taito; Fujita, Makoto; Reek, Joost N H

    2016-10-17

    There is broad interest in molecular encapsulation as such systems can be utilized to stabilize guests, facilitate reactions inside a cavity, or give rise to energy-transfer processes in a confined space. Detailed understanding of encapsulation events is required to facilitate functional molecular encapsulation. In this contribution, it is demonstrated that Ir and Rh-Cp-type metal complexes can be encapsulated inside a self-assembled M 6 L 4 metallocage only in the presence of an aromatic compound as a second guest. The individual guests are not encapsulated, suggesting that only the pair of guests can fill the void of the cage. Hence, selective co-encapsulation is observed. This principle is demonstrated by co-encapsulation of a variety of combinations of metal complexes and aromatic guests, leading to several ternary complexes. These experiments demonstrate that the efficiency of formation of the ternary complexes depends on the individual components. Moreover, selective exchange of the components is possible, leading to formation of the most favorable complex. Besides the obvious size effect, a charge-transfer interaction may also contribute to this effect. Charge-transfer bands are clearly observed by UV/Vis spectrophotometry. A change in the oxidation potential of the encapsulated electron donor also leads to a shift in the charge-transfer energy bands. As expected, metal complexes with a higher oxidation potential give rise to a higher charge-transfer energy and a larger hypsochromic shift in the UV/Vis spectrum. These subtle energy differences may potentially be used to control the binding and reactivity of the complexes bound in a confined space. © 2016 The Authors. Published by Wiley-VCH Verlag GmbH & Co. KGaA.

  10. Development of highly durable deep-ultraviolet AlGaN-based LED multichip array with hemispherical encapsulated structures using a selected resin through a detailed feasibility study

    Science.gov (United States)

    Nagai, Shoko; Yamada, Kiho; Hirano, Akira; Ippommatsu, Masamichi; Ito, Masahiro; Morishima, Naoki; Aosaki, Ko; Honda, Yoshio; Amano, Hiroshi; Akasaki, Isamu

    2016-08-01

    To replace mercury lamps with AlGaN-based deep-ultraviolet (DUV) LEDs, a simple and low-cost package with increased light extraction efficiency (LEE) is indispensable. Therefore, resin encapsulation is considered to be a key technology. However, the photochemical reactions induced by DUV light cause serious problems, and conventional resins cannot be used. In the former part of this study, a comparison of a silicone resin and fluorine polymers was carried out in terms of their suitability for encapsulation, and we concluded that only one of the fluorine polymers can be used for encapsulation. In the latter part, the endurance of encapsulation using the selected fluorine polymer was investigated, and we confirmed that the selected fluorine polymer can guarantee a lifetime of over 6,000 h at a wavelength of 265 nm. Furthermore, a 3 × 4 array module of encapsulated dies on a simple AlN submount was fabricated, demonstrating the possibility of W/cm2-class lighting.

  11. Encapsulated Unresolved Subdural Hematoma Mimicking Acute Epidural Hematoma: A Case Report

    Science.gov (United States)

    Park, Sang-Soo; Kim, Hyo-Joon; Kwon, Chang-Young

    2014-01-01

    Encapsulated acute subdural hematoma (ASDH) has been uncommonly reported. To our knowledge, a few cases of lentiform ASDH have been reported. The mechanism of encapsulated ASDH has been studied but not completely clarified. Encapsulated lentiform ASDH on a computed tomography (CT) scan mimics acute epidural hematoma (AEDH). Misinterpretation of biconvex-shaped ASDH on CT scan as AEDH often occurs and is usually identified by neurosurgical intervention. We report a case of an 85-year-old man presenting with a 2-day history of mental deterioration and right-sided weakness. CT scan revealed a biconvex-shaped hyperdense mass mixed with various densities of blood along the left temporoparietal cerebral convexity, which was misinterpreted as AEDH preoperatively. Emergency craniectomy was performed, but no AEDH was found beneath the skull. In the subdural space, encapsulated ASDH was located. En block resection of encapsulated ASDH was done. Emergency craniectomy confirmed that the preoperatively diagnosed AEDH was an encapsulated ASDH postoperatively. Radiologic studies of AEDH-like SDH allow us to establish an easy differential diagnosis between AEDH and ASDH by distinct features. More histological studies will provide us information on the mechanism underlying encapsulated ASDH. PMID:27169052

  12. Design, characterisation and application of alginate-based encapsulated pig liver esterase.

    Science.gov (United States)

    Pauly, Jan; Gröger, Harald; Patel, Anant V

    2018-06-05

    Encapsulation of hydrolases in biopolymer-based hydrogels often suffers from low activities and encapsulation efficiencies along with high leaching and unsatisfactory recycling properties. Exemplified for the encapsulation of pig liver esterase the coating of alginate and chitosan beads have been studied by creating various biopolymer hydrogel beads. Enzyme activity and encapsulation efficiency were notably enhanced by chitosan coating of alginate beads while leaching remained nearly unchanged. This was caused by the enzymatic reaction acidifying the matrix, which increased enzyme retention through enhanced electrostatic enzyme-alginate interaction but decreased activity through enzyme deactivation. A practical and ready-to-use method for visualising pH in beads during reaction by co-encapsulation of a conventional pH indicator was also found. Our method proves that pH control inside the beads can only be realised by buffering. The resulting beads provided a specific activity of 0.267 μmol ∙ min -1 ∙ mg -1 , effectiveness factor 0.88, encapsulation efficiency of 88%, 5% leaching and good recycling properties. This work will contribute towards better understanding and application of encapsulated hydrolases for enzymatic syntheses. Copyright © 2018 Elsevier B.V. All rights reserved.

  13. Simultant encapsulation of vitamin C and beta-carotene in sesame (Sesamum indicum l.) liposomes

    Science.gov (United States)

    Hudiyanti, D.; Fawrin, H.; Siahaan, P.

    2018-04-01

    In this study sesame liposomes were used to encapsulate both vitamin C and beta-carotene simultaneously. Liposomes were prepared with addition of cholesterol. The encapsulation efficiency (EE) of sesame liposomes for vitamin C in the present of beta-carotene was 77%. The addition of cholesterol increased the encapsulation efficiency. The highest encapsulation efficiency was 89% obtained in liposomes with 10% and 20% cholesterol. Contrary to that, the highest beta-carotene encapsulation efficiency of 78%, was found in the sesame liposomes prepared without the added cholesterol. Results showed that sesame liposomes can be used to encapsulate beta-carotene and vitamin C simultaneously. When beta-carotene and vitamin C were encapsulated concurrently, cholesterol intensified the efficiency of vitamin C encapsulation on the contrary it diminished the efficiency of beta-carotene encapsulation.

  14. Development of the double encapsulated sources of Ir 192 for industrial applications

    International Nuclear Information System (INIS)

    Munoz, C; Sabio Calvete, M; Bianchi, D; Banchik, D; Gonzalez, A; Mender, A

    2004-01-01

    The steps are described that were followed for carrying out the scientific and technological development of the double encapsulated sources for the Iridium-192 to be used in industrial gammagraphy. This development arises from an agreement between INVAP and the CNEA as part of the EGIPTO Project. Each step is outlined in the development together with the different experiences undertaken to obtain the source, whose construction meets the local and international standards for safety and radiological protection (ARN, IRAM, ISO standards) (Cw)

  15. Encapsulated social perception of emotional expressions.

    Science.gov (United States)

    Smortchkova, Joulia

    2017-01-01

    In this paper I argue that the detection of emotional expressions is, in its early stages, informationally encapsulated. I clarify and defend such a view via the appeal to data from social perception on the visual processing of faces, bodies, facial and bodily expressions. Encapsulated social perception might exist alongside processes that are cognitively penetrated, and that have to do with recognition and categorization, and play a central evolutionary function in preparing early and rapid responses to the emotional stimuli. Copyright © 2016 Elsevier Inc. All rights reserved.

  16. Encapsulation Technology for Delivery of Medical Therapeutics

    Data.gov (United States)

    National Aeronautics and Space Administration — The NASA Biocapsule technology is a novel drug deilivery system that uses living cells contained in a specialized biocompatible container that can be implanted into...

  17. Thermal stability of carbon-encapsulated Fe-Nd-B nanoparticles

    International Nuclear Information System (INIS)

    Bystrzejewski, M.; Cudzilo, S.; Huczko, A.; Lange, H.

    2006-01-01

    Thermal stability of various magnetic nanomaterials is very essential, due to their prospective future applications. In this paper, thermal behaviour of the carbon-encapsulated Fe-Nd-B nanoparticles is studied. These nanostructures were produced by direct current arcing of carbon anodes filled with Nd 2 Fe 14 B material. The thermogravimetry and differential thermal analysis curves were recorded in an oxygen atmosphere. The thermal processes were monitored by X-ray diffraction to follow the changes in the phase composition. The investigated samples have been thermally stable up to 600 K

  18. Cell-based delivery of glucagon-like peptide-1 using encapsulated mesenchymal stem cells.

    Science.gov (United States)

    Wallrapp, Christine; Thoenes, Eric; Thürmer, Frank; Jork, Anette; Kassem, Moustapha; Geigle, Peter

    2013-01-01

    Glucagon-like peptide-1 (GLP-1) CellBeads are cell-based implants for the sustained local delivery of bioactive factors. They consist of GLP-1 secreting mesenchymal stem cells encapsulated in a spherically shaped immuno-isolating alginate matrix. A highly standardized and reproducible encapsulation method is described for the manufacturing of homogeneous CellBeads. Viability and sustained secretion was shown for the recombinant GLP-1 and the cell endogenous bioactive factors like vascular endothelial growth factor, neurotrophin 3 (NT-3) and glial cell line-derived neurotrophic factor. Manufacturing and quality control is performed in compliance with good manufacturing practice and fulfils all regulatory requirements for human clinical use. GLP-1 CellBeads combine the neuro- and cardioprotective properties of both GLP-1 and mesenchymal stem cells. First promising results were obtained from preclinical studies and an ongoing safety trial in humans but further studies have to prove the overall potential of CellBead technology in cell-based regenerative medicine.

  19. Process and Material Design for Micro-Encapsulated Ionic Liquids in Post-Combustion CO2 Capture

    Energy Technology Data Exchange (ETDEWEB)

    Hong, Bo [Univ. of Notre Dame, IN (United States); Brennecke, Joan F [Univ. of Notre Dame, IN (United States); McCready, Mark [Univ. of Notre Dame, IN (United States); Stadtherr, Mark [Univ. of Notre Dame, IN (United States)

    2016-11-18

    Aprotic Heterocyclic Anion (AHA) Ionic Liquids (ILs) have been identified as promising new solvents for post-combustion carbon capture due to their high CO2 uptake and the high tenability 1,2 of their binding energy with CO2. Some of these compounds change phase (solid to liquid) on absorption of CO2; these Phase Change ILs (PCILs)3 offer the additional advantage that part of the heat needed to desorb the CO2 from the absorbent is provided by the heat of fusion as the PCIL solidifies upon release of CO2. However, the relatively high viscosity of AHA ILs and the occurrence of a phase change in PCILs present challenges for conventional absorption equipment. To overcome these challenges we are pursuing the use of new technology to micro-encapsulate the AHA ILs and PCILs. Our partners at Lawrence Livermore National Laboratory have successfully demonstrated this technology in the application of post-combustion carbon capture with sodium and potassium carbonate solutions,4 and have recently shown the feasibility of micro-encapsulation of an AHA IL for carbon capture.5 The large effective surface area and high CO2 permeability of the micro-capsules is expected to offset the drawback of the high IL viscosity and to provide for a more efficient and cost-effective mass transfer operation involving AHA ILs and PCILs. These opportunities, however, present us with both process and materials design questions. For example, what is the target CO2 absorption strength (enthalpy of chemical absorption) for the tunable AHA IL? What is the target for micro-capsule diameter in order to obtain a high mass transfer rate and good fluidization performance? What are the appropriate temperatures and pressures for the absorber and stripper? In order to address these and other questions, we have developed a rate-based model of a post-combustion CO2 capture process using micro-encapsulated ILs. As a performance baseline

  20. Antidiabetic activity from cinnamaldydhe encapsulated by nanochitosan

    Science.gov (United States)

    Purbowatingrum; Ngadiwiyana; Fachriyah, E.; Ismiyarto; Ariestiani, B.; Khikmah

    2018-04-01

    Diabetes mellitus (DM) is a disease characterized by chronic hyperglycemia and metabolic disorders of carbohydrates, proteins, and fats due to reduced function of insulin. Treatment of diabetes can be done by insulin therapy or hypoglycemic drugs. Hypoglycemic drugs usually contain compounds that can inhibit the action of α-glucosidase enzymes that play a role in breaking carbohydrates into blood sugar. Cinnamaldehyde has α-glucosidase inhibit activity because it has a functional group of alkene that is conjugated with a benzene ring and a carbonyl group. However, the use of this compound still provides unsatisfactory results due to its degradation during the absorption process. The solution offered to solve the problem is by encapsulated it within chitosan nanoparticles that serve to protect the bioactive compound from degradation, increases of solubility and delivery of a bioactive compound to the target site by using freeze-drying technique. The value of encapsulation efficiency (EE) of cinnamaldyhde which encapsulated within chitosan nanoparticles is about 74%. Inhibition test result showed that cinnamaldehyde-chitosan nanoparticles at 100 ppm could inhibit α-glucosidase activity in 23.9% with 134,13 in IC50. So it can be concluded that cinnamaldehyde can be encapsulated in nanoparticles of chitosan and proved that it could inhibit α-glucosidase.

  1. Nano spray drying for encapsulation of pharmaceuticals.

    Science.gov (United States)

    Arpagaus, Cordin; Collenberg, Andreas; Rütti, David; Assadpour, Elham; Jafari, Seid Mahdi

    2018-05-17

    Many pharmaceuticals such as pills, capsules, or tablets are prepared in a dried and powdered form. In this field, spray drying plays a critical role to convert liquid pharmaceutical formulations into powders. In addition, in many cases it is necessary to encapsulate bioactive drugs into wall materials to protect them against harsh process and environmental conditions, as well as to deliver the drug to the right place and at the correct time within the body. Thus, spray drying is a common process used for encapsulation of pharmaceuticals. In view of the rapid progress of nanoencapsulation techniques in pharmaceutics, nano spray drying is used to improve drug formulation and delivery. The nano spray dryer developed in the recent years provides ultrafine powders at nanoscale and high product yields. In this paper, after explaining the concept of nano spray drying and understanding the key elements of the equipment, the influence of the process parameters on the final powders properties, like particle size, morphology, encapsulation efficiency, drug loading and release, will be discussed. Then, numerous application examples are reviewed for nano spray drying and encapsulation of various drugs in the early stages of product development along with a brief overview of the obtained results and characterization techniques. Copyright © 2018 Elsevier B.V. All rights reserved.

  2. Plantlets from encapsulated shoot buds of Catalpa ovata G. Don

    Directory of Open Access Journals (Sweden)

    Halina Wysokińska

    2014-01-01

    Full Text Available Shoot buds isolated from in vitro shoot cultures of Catalpa ovata G. Don were encapsulated using 3% sodium alginate with sucrose (3% and 50 mM calcium chloride. The morphogenic response of encapsulated buds was affected by such factors, like composition of the media and the presence of growth regulators. The highest frequency of plantlet germination from encapsulated buds (70% within 4 weeks was obtained on Woody Plant medium (WP (Lloyd and McCown 1980 containing indole-3-butyric acid (IBA (1 mg/l. The process was substantially inhibited by cold-storage (4oC of encapsulated buds. In this case, the frequency response ranged from 3% to 22% dependent on storage period (28 or 42 days and the presence of the paraffin coat covering the alginate capsules. The plantlets developed from both unstored and stored encapsulated buds of C. ovata were transplanted to soil and grew in pots to phenotypically normal plants.

  3. Electromagnetic properties of conducting polymers encapsulated in an insulating matrix

    International Nuclear Information System (INIS)

    Esnouf, Stephane

    1995-01-01

    The aim of this work is to study the electronic properties of conducting polymers encapsulated in zeolite. We studied two kinds of polymers: intrinsic conducting polymers (poly-pyrrole) and pyrolyzed polymers (polyacrylonitrile and poly-furfuryl alcohol). These systems were characterized by electron paramagnetic resonance and microwave conductivity measurements. In the first part, we present the preparation and the characterization of encapsulated poly-pyrrole. Conductivity measurements show that the encapsulated material is insulating, certainly because a strong interaction with the zeolite traps the charge carriers. In the second part, we focus on pyrolyzed encapsulated polyacrylonitrile. This system has a metal-like susceptibility at room temperature and a relatively high microwave conductivity. These results demonstrate the formation during the pyrolysis of extended aromatic clusters. Finally, we study pyrolyzed encapsulated poly-furfuryl alcohol. We show that the only effect of the pyrolysis is to fragment the polymers. We also discuss the spin relaxation and the EPR line broadening. (author) [fr

  4. Microencapsulation: concepts, mechanisms, methods and some applications in food technology

    Directory of Open Access Journals (Sweden)

    Pablo Teixeira da Silva

    2014-07-01

    Full Text Available Microencapsulation is a process in which active substances are coated by extremely small capsules. It is a new technology that has been used in the cosmetics industry as well as in the pharmaceutical, agrochemical and food industries, being used in flavors, acids, oils, vitamins, microorganisms, among others. The success of this technology is due to the correct choice of the wall material, the core release form and the encapsulation method. Therefore, in this review, some relevant microencapsulation aspects, such as the capsule, wall material, core release forms, encapsulation methods and their use in food technology will be briefly discussed.

  5. Encapsulation of Aloe Vera and Its Effect During Yogur Incubation

    Directory of Open Access Journals (Sweden)

    Ricardo Adolfo Parra Huertas

    2014-11-01

    Full Text Available The yogurt is milk derivative highly consumed around the world,as well as aloe vera. Both have reports tocontribute to human health. The purpose of this research is to determine the effect of the addition of capsules with aloe vera during the incubation of yogurt. Aloeverawas encapsulated in alginate at two different concentrations, 1% and 2%,addingthe capsules from the moment of incubation and comparing the effect of the addition of capsules withthe non-addition of them. For these samples were determined: pH, acidity, syneresis, lactic acid bacteria count, sensory evaluation and proximate analysis. The results indicated that for the three treatments pH values and acid behaved similarly to each characteristic of the yogurt during incubation. The lactic acid bacteria count indicated that treatment with capsules containing 2% sodium alginate had higher counts. Sensorially, three treatments had a favorable acceptability; proximate analysis had favorable values . In conclusion,the tests showed the viability of encapsulated aloe vera in the manufacture of yogurt during incubation time without being affected by the concentration of sodium alginate.

  6. Comparison of cell encapsulation technologies for single pressure vessel nickel-hydrogen battery

    Energy Technology Data Exchange (ETDEWEB)

    Rao, G. [National Aeronautics and Space Administration, Greenbelt, MD (United States). Goddard Space Flight Center; Vaidyanathan, H. [COMSAT Labs., Clarksburg, MD (United States)

    1996-12-31

    Two single pressure vessel (SPV) batteries containing 22 series-connected nickel-hydrogen (Ni-H{sub 2}) cells of 19-Ah capacity were designed and procured from Eagle-Picher Industries. The two batteries were similar in mechanical design, dimensions, and composition of the active core. However, they differed in cell encapsulation, location and structure of the gas diffusion membrane, and cell activation. Both batteries have been subjected to detailed flight qualification testing at COMSAT Laboratories. The batteries met the requirements in capacity, capacity retention, discharge voltage, impedance, thermal behavior in vacuum, and response to vibration. The batteries are currently being cycle tested in a low earth orbit (LEO) regime using V-T charge control at a depth of discharge of 40% and at 20 C. The battery design, and its characterization, environmental, and LEO cycle test data are presented.

  7. Subcutaneous encapsulated fat necrosis

    DEFF Research Database (Denmark)

    Aydin, Dogu; Berg, Jais O

    2016-01-01

    We have described subcutaneous encapsulated fat necrosis, which is benign, usually asymptomatic and underreported. Images have only been published on two earlier occasions, in which the necrotic nodules appear "pearly" than the cloudy yellow surface in present case. The presented image may help...

  8. Ultrasonographic findings of sclerosing encapsulating peritonitis

    Energy Technology Data Exchange (ETDEWEB)

    Han, Jong Kyu; Lee, Hae Kyung; Moon, Chul; Hong, Hyun Sook; Kwon, Kwi Hyang; Choi, Deuk Lin [Soonchunhyangi University College of Medicine, Seoul (Korea, Republic of)

    2001-03-15

    To evaluate the ultrasonographic findings of the patients with sclerosing encapsulating peritonitis (SEP). Thirteen patients with surgically confirmed sclerosing encapsulating peritonitis were involved in this study. Because of intestinal obstruction, all patients had received operations. Among 13 patients, 12 cases had continuous ambulatory peritoneal dialysis (CAPD) for 2 months-12 years and 4 months from (mean; 6 years and 10 months), owing to chronic renal failure and one patient had an operation due to variceal bleeding caused by liver cirrhosis. On ultrasonographic examination, all patients showed loculated ascites which were large (n=7) or small (n=6) in amount with multiple separations. The small bowel loops were tethered posteriorly perisaltic movement and covered with the thick membrane. The ultrasonographic of findings of sclerosing encapsulating peritonitis were posteriorly tethered small bowels covered with a thick membrane and loculated ascites with multiple septa. Ultrasonographic examination can detect the thin membrane covering the small bowel loops in the early phase of the disease, therefore ultrasonography would be a helpful modality to diagnose SEP early.

  9. A comprehensive overview on the micro- and nano-technological encapsulation advances for enhancing the chemical stability and bioavailability of carotenoids.

    Science.gov (United States)

    Soukoulis, Christos; Bohn, Torsten

    2018-01-02

    Carotenoids are lipophilic secondary plant compounds, and their consumption within fruits and vegetables has been positively correlated with a decreased risk of developing several chronic diseases. However, their bioavailability is often compromised due to incomplete release from the food matrix, poor solubility and potential degradation during digestion. In addition, carotenoids in food products are prone to oxidative degradation, not only lowering the nutritional value of the product but also triggering other quality deteriorative changes, such as formation of lipid pro-oxidants (free radicals), development of discolorations or off-flavor defects. Encapsulation refers to a physicochemical process, aiming to entrap an active substance in structurally engineered micro- or nano-systems, in order to develop an effective thermodynamical and physical barrier against deteriorative environmental conditions, such as water vapor, oxygen, light, enzymes or pH. In this context, encapsulation of carotenoids has shown to be a very effective strategy to improve their chemical stability under common processing conditions including storage. In addition, encapsulation may also enhance bioavailability (via influencing bioaccessibility and absorption) of lipophilic bioactives, via modulating their release kinetics from the carrier system, solubility and interfacial properties. In the present paper, it is aimed to present the state of the art of carotenoid microencapsulation in order to enhance storability and bioavailability alike.

  10. Encapsulation of bacteria and viruses in electrospun nanofibres

    International Nuclear Information System (INIS)

    Salalha, W; Kuhn, J; Dror, Y; Zussman, E

    2006-01-01

    Bacteria and viruses were encapsulated in electrospun polymer nanofibres. The bacteria and viruses were suspended in a solution of poly(vinyl alcohol) (PVA) in water and subjected to an electrostatic field of the order of 1 kV cm -1 . Encapsulated bacteria in this work (Escherichia coli, Staphylococcus albus) and bacterial viruses (T7, T4, λ) managed to survive the electrospinning process while maintaining their viability at fairly high levels. Subsequently the bacteria and viruses remain viable during three months at -20 and -55 deg. C without a further decrease in number. The present results demonstrate the potential of the electrospinning process for the encapsulation and immobilization of living biological material

  11. Recovery of reactor electrical assemblies using differential de-encapsulation to remove dielectric insulation systems

    International Nuclear Information System (INIS)

    Hubrig, J.G.; Hammerstone, E.B.

    1986-01-01

    State-of-the-art de-encapsulation technologies associated with the conventional dielectric insulation systems employed in the construction of electrical coils and power distribution systems do not allow for accurate fatigue/failure analysis or reliable recovery of costly assembly components. Differential de-encapsulation allows for the selective removal of contemporary thermoset resin based insulation systems to allow non-destructive penetration of insulation wall thicknesses to both examine critical areas and recover high performance metallic and non-metallic inserts for remanufacture; significantly reducing replacement costs and reactor downtime. The authors' analysis describes how the availability of engineering data from the selective and non-destructive removal of insulation materials will aid in the evaluation of original manufacture, materials and procedures; enabling redesign to enhance subsequent on line performance. They also discuss why the ability to recover coil and core assemblies for remanufacture will have a major economic impact on reactor management costs

  12. NANOEMULSIFIKASI SPONTAN EKSTRAK JINTAN HITAM DAN KARAKTERISTIK PRODUK ENKAPSULASINYA [Spontaneous Nanoemulsification of Black Cumin Extract and the Characteristics of the Encapsulation Product

    Directory of Open Access Journals (Sweden)

    Rovie Farah Diba1*

    2014-12-01

    Full Text Available Research on the use of low energy nano technology on black cumin is still limited. Encapsulation of black cumin extract nanoemulsion has been developed and the products have been characterized. The aims of this study were to determine the extraction method of the black cumin seed, produce black cumin extract nanoemulsion by spontaneous emulsification technique, and produce encapsulated black cumin extract nanoemulsion. Three steps of experiments were done in this study, i.e. extraction, nanoemulsification and encapsulation. In the first step, extraction was done using maceration and reflux methods and the best result was sent to the next step. Second, a spontaneous nanoemulsification was performed using organic phase (ethanol 70%, and water phase (Tween 80 solution at 1, 2 and 3% w/w to produce the best nanoemulsion. Finally, the best nanoemulsion based on size, homogeneity, and stability of the particles, was encapsulated using two different encapsulating material compositions, i.e. maltodextrin (100% and a combination of maltodextrin and soy protein isolate at a ratio of 80 : 20 (w/w. The results showed that the three-hour reflux method produced better black cumin extract properties than that of maceration. Use of 3% surfactant gave a stable nanoemulsion with average droplet size of 10.93 nm. Reconstitution of the encapsulated nanoemulsion resulted in products with more spherical globules, indicating an efficient encapsulation process. The combination of of maltodextrin and soy protein isolate provided a better preservation of phenolic content and antioxidant capacity as compared to the use of maltodextrin alone.

  13. Biodegradable polycaprolactone (PCL) nanosphere encapsulating superoxide dismutase and catalase enzymes.

    Science.gov (United States)

    Singh, Sushant; Singh, Abhay Narayan; Verma, Anil; Dubey, Vikash Kumar

    2013-12-01

    Biodegradable polycaprolactone (PCL) nanosphere encapsulating superoxide dismutase (SOD) and catalase (CAT) were successfully synthesized using double emulsion (w/o/w) solvent evaporation technique. Characterization of the nanosphere using dynamic light scattering, field emission scanning electron microscope, and Fourier transform infrared spectroscopy revealed a spherical-shaped nanosphere in a size range of 812 ± 64 nm with moderate protein encapsulation efficiency of 55.42 ± 3.7 % and high in vitro protein release. Human skin HaCat cells were used for analyzing antioxidative properties of SOD- and CAT-encapsulated PCL nanospheres. Oxidative stress condition in HaCat cells was optimized with exposure to hydrogen peroxide (H2O2; 1 mM) as external stress factor and verified through reactive oxygen species (ROS) analysis using H2DCFDA dye. PCL nanosphere encapsulating SOD and CAT together indicated better antioxidative defense against H2O2-induced oxidative stress in human skin HaCat cells in comparison to PCL encapsulating either SOD or CAT alone as well as against direct supplement of SOD and CAT protein solution. Increase in HaCat cells SOD and CAT activities after treatment hints toward uptake of PCL nanosphere into the human skin HaCat cells. The result signifies the role of PCL-encapsulating SOD and CAT nanosphere in alleviating oxidative stress.

  14. Investigations into encapsulation of intermediate level wastes containing organic components

    International Nuclear Information System (INIS)

    Palmer, J.

    1988-01-01

    A product evaluation programme was set up to investigate the properties of a variety of matrix-waste formulations prior to their encapsulation. The waste/matrix forms were defined and characterised and waste pretreatments studied. Potential encapsulation matrices were investigated for their suitability for individual waste streams. The physical, chemical and thermal properties, radiation stability and leaching behaviour of the formulations were studied. Operational and design limits for the encapsulation plant were defined. (U.K.)

  15. Characterization studies of lower and non-TDI polyurethane encapsulants

    International Nuclear Information System (INIS)

    Wilson, M.H.

    1993-09-01

    Polyurethane prepolymers containing toluene diisocyanate (TDI) are used within the Nuclear Weapons complex for many adhesive and encapsulation applications. As part of a program for minimizing hazards to workers and the environment, TDI will be eliminated. This report presents evaluation of alternative encapsulants

  16. Introducing lattice strain to graphene encapsulated in hBN

    Science.gov (United States)

    Tomori, Hikari; Hiraide, Rineka; Ootuka, Youiti; Watanabe, Kenji; Taniguchi, Takashi; Kanda, Akinobu

    Due to the characteristic lattice structure, lattice strain in graphene produces an effective gauge field. Theories tell that by controlling spatial variation of lattice strain, one can tailor the electronic state and transport properties of graphene. For example, under uniaxial local strain, graphene exhibits a transport gap at low energies, which is attractive for a graphene application to field effect devices. Here, we develop a method for encapsulating a strained graphene film in hexagonal boron-nitride (hBN). It is known that the graphene carrier mobility is significantly improved by the encapsulation of graphene in hBN, which has never been applied to strained graphene. We encapsulate graphene in hBN using the van der Waals assembly method. Strain is induced by sandwiching a graphene film between patterned hBN sheets. Spatial variation of strain is confirmed with micro Raman spectroscopy. Transport measurement of encapsulated strained graphene is in progress.

  17. Phospholipid Fatty Acids as Physiological Indicators of Paracoccus denitrificans Encapsulated in Silica Sol-Gel Hydrogels

    Directory of Open Access Journals (Sweden)

    Josef Trögl

    2015-02-01

    Full Text Available The phospholipid fatty acid (PLFA content was determined in samples of Paracoccus denitrificans encapsulated in silica hydrogel films prepared from prepolymerized tetramethoxysilane (TMOS. Immediately after encapsulation the total PLFA concentration was linearly proportional to the optical density (600 nm of the input microbial suspension (R2 = 0.99. After 7 days this relationship remained linear, but with significantly decreased slope, indicating a higher extinction of bacteria in suspensions of input concentration 108 cells/mL and higher. trans-Fatty acids, indicators of cytoplasmatic membrane disturbances, were below the detection limit. The cy/pre ratio (i.e., ratio of cyclopropylated fatty acids (cy17:0 + cy19:0 to their metabolic precursors (16:1ω7 + 18:1ω7, an indicator of the transition of the culture to a stationary growth-phase, decreased depending on co-immobilization of nutrients in the order phosphate buffer > mineral medium > Luria Broth rich medium. The ratio, too, was logarithmically proportional to cell concentration. These results confirm the applicability of total PLFA as an indicator for the determination of living biomass and cy/pre ratio for determination of nutrient limitation of microorganisms encapsulated in sol-gel matrices. This may be of interest for monitoring of sol-gel encapsulated bacteria proposed as optical recognition elements in biosensor construction, as well as other biotechnological applications.

  18. Nondestructive Assay Options for Spent Fuel Encapsulation

    Energy Technology Data Exchange (ETDEWEB)

    Tobin, Stephen J. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Jansson, Peter [Uppsala Univ. (Sweden)

    2014-10-02

    This report describes the role that nondestructive assay (NDA) techniques and systems of NDA techniques may have in the context of an encapsulation and deep geological repository. The potential NDA needs of an encapsulation and repository facility include safeguards, heat content, and criticality. Some discussion of the facility needs is given, with the majority of the report concentrating on the capability and characteristics of individual NDA instruments and techniques currently available or under development. Particular emphasis is given to how the NDA techniques can be used to determine the heat production of an assembly, as well as meet the dual safeguards needs of 1) determining the declared parameters of initial enrichment, burn-up, and cooling time and 2) detecting defects (total, partial, and bias). The report concludes with the recommendation of three integrated systems that might meet the combined NDA needs of the encapsulation/repository facility.

  19. Nuclear-waste encapsulation by metal-matrix casting

    International Nuclear Information System (INIS)

    Nelson, R.G.; Nesbitt, J.F.; Slate, S.C.

    1981-05-01

    Several encapsulation casting processes are described that were developed or used at the Pacific Northwest Laboratory to embed simulated high-level wastes of two different forms (glass marbles and ceramic pellets) in metal matrices. Preliminary evaluations of these casting processes and the products are presented. Demonstrations have shown that 5- to 10-mm-dia glass marbles can be encapsulated on an engineering scale with lead or lead alloys by gravity or vacuum processes. Marbles approx. 12 mm in dia were successfully encapsulated in a lead alloy on a production scale. Also, 4- to 9-mm-dia ceramic pellets in containers of various sizes were completely penetrated and the individual pellets encased with aluminum-12 wt % silicon alloy by vacuum processes. Indications are that of the casting processes tested, aluminum 12 wt % silicon alloy vacuum-cast around ceramic pellets had the highest degree of infiltration or coverage of pellet surfaces

  20. Rapid and effective sample cleanup based on graphene oxide-encapsulated core–shell magnetic microspheres for determination of fifteen trace environmental phenols in seafood by liquid chromatography–tandem mass spectrometry

    Energy Technology Data Exchange (ETDEWEB)

    Pan, Sheng-Dong; Chen, Xiao-Hong [Key Laboratory of Health Risk Appraisal for Trace Toxic Chemicals of Zhejiang Province, Ningbo Municipal Center for Disease Control and Prevention, Ningbo, Zhejiang 315010 (China); Ningbo Key Laboratory of Poison Research and Control, Ningbo Municipal Center for Disease Control and Prevention, Ningbo 315010 (China); Shen, Hao-Yu [Ningbo Institute of Technology, Zhejiang University, Ningbo, Zhejiang 315100 (China); Li, Xiao-Ping [Key Laboratory of Health Risk Appraisal for Trace Toxic Chemicals of Zhejiang Province, Ningbo Municipal Center for Disease Control and Prevention, Ningbo, Zhejiang 315010 (China); Ningbo Key Laboratory of Poison Research and Control, Ningbo Municipal Center for Disease Control and Prevention, Ningbo 315010 (China); Cai, Mei-Qiang [School of Environmental Science and Engineering, Zhejiang Gongshang University, Hangzhou 310018 (China); Zhao, Yong-Gang [Key Laboratory of Health Risk Appraisal for Trace Toxic Chemicals of Zhejiang Province, Ningbo Municipal Center for Disease Control and Prevention, Ningbo, Zhejiang 315010 (China); Ningbo Key Laboratory of Poison Research and Control, Ningbo Municipal Center for Disease Control and Prevention, Ningbo 315010 (China); Jin, Mi-Cong, E-mail: jmcjc@163.com [Key Laboratory of Health Risk Appraisal for Trace Toxic Chemicals of Zhejiang Province, Ningbo Municipal Center for Disease Control and Prevention, Ningbo, Zhejiang 315010 (China); Ningbo Key Laboratory of Poison Research and Control, Ningbo Municipal Center for Disease Control and Prevention, Ningbo 315010 (China)

    2016-05-05

    In this study, graphene oxide-encapsulated core–shell magnetic microspheres (GOE-CS-MM) were fabricated by a self-assemble approach between positive charged poly(diallyldimethylammonium) chloride (PDDA)-modified Fe{sub 3}O{sub 4}@SiO{sub 2} and negative charged GO sheets via electrostatic interaction. The as-prepared GOE-CS-MM was carefully characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), vibrating sample magnetometer analysis (VSM), and X-ray photoelectron spectroscopy (XPS), and was used as a cleanup adsorbent in magnetic solid-phase extraction (MSPE) for determination of 15 trace-level environmental phenols in seafood coupled to liquid chromatography–tandem mass spectrometry (LC–MS/MS). The obtained results showed that the GOE-CS-MM exhibited excellent cleanup efficiency and could availably reduce the matrix effect. The cleanup mechanisms were investigated and referred to π–π stacking interaction and hydrogen bond between GOE-CS-MM and impurities in the extracts. Moreover, the extraction and cleanup conditions of GOE-CS-MM toward phenols were optimized in detail. Under the optimized conditions, the limits of detection (LODs) were found to be 0.003–0.06 μg kg{sup −1}, and satisfactory recovery values of 84.8–103.1% were obtained for the tested seafood samples. It was confirmed that the developed method is simple, fast, sensitive, and accurate for the determination of 15 trace environmental phenols in seafood samples. - Highlights: • Novel graphene oxide-encapsulated core-shell magnetic microspheres (GOE-CS-MM) were fabricated by a self-assemble approach. • The as-prepared material GOE-CS-MM exhibited excellent cleanup efficiency and could availably reduce the matrix effect. • The cleanup mechanisms refer to π–π stacking interaction and hydrogen bond. • The developed MSPE–LC–MS/MS method was simple, fast, sensitive and accurate.

  1. Light outputs of LED with various refractive indices and geometrical structures of encapsulants

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Kyung-Tae [Chosun University, Gwangju (Korea, Republic of); Jo, Kyoung-Woo; Hwang, Jung-Ha; Kwon, Ho-Ki [LG Innotek Co., Ltd., Seoul (Korea, Republic of); Park, Si-Hyun [Yeungnam University, Gyeongsan (Korea, Republic of)

    2010-12-15

    In this paper we present the results of experiments and simulations for the light output power from LEDs for various refractive indices and the geometrical structures of the LED encapsulants. InGaN-based LED chips were fabricated and were bonded in Ag reflector cups within polyphthalamide (PPA) chip carriers; then, encapsulants with various refractive indices and the geometrical structures were fabricated onto them by using a dispensing method. The light output power with the encapsulant was shown to increase with the refractive index of the encapsulant materials in the case of a spherical encapsulant while it decreased in the case of a flat geometry encapsulant. We performed ray tracing simulations for the LED light output and confirmed that the simulation results were consistent with our experimentally measured results. In addition, the light output with the encapsulant rapidly increased with the sidewall angle of the chip carrier in the case of the flat encapsulant while it was not affected by the sidewall angle, remaining constant, in the case of the spherical geometry.

  2. Light outputs of LED with various refractive indices and geometrical structures of encapsulants

    International Nuclear Information System (INIS)

    Kim, Kyung-Tae; Jo, Kyoung-Woo; Hwang, Jung-Ha; Kwon, Ho-Ki; Park, Si-Hyun

    2010-01-01

    In this paper we present the results of experiments and simulations for the light output power from LEDs for various refractive indices and the geometrical structures of the LED encapsulants. InGaN-based LED chips were fabricated and were bonded in Ag reflector cups within polyphthalamide (PPA) chip carriers; then, encapsulants with various refractive indices and the geometrical structures were fabricated onto them by using a dispensing method. The light output power with the encapsulant was shown to increase with the refractive index of the encapsulant materials in the case of a spherical encapsulant while it decreased in the case of a flat geometry encapsulant. We performed ray tracing simulations for the LED light output and confirmed that the simulation results were consistent with our experimentally measured results. In addition, the light output with the encapsulant rapidly increased with the sidewall angle of the chip carrier in the case of the flat encapsulant while it was not affected by the sidewall angle, remaining constant, in the case of the spherical geometry.

  3. Steel Bar corrosion monitoring based on encapsulated piezoelectric sensors

    Science.gov (United States)

    Xu, Ying; Tang, Tianyou

    2018-05-01

    The durability of reinforced concrete has a great impact on the structural bearing capacity, while the corrosion of steel bars is the main reason for the degradation of structural durability. In this paper, a new type of encapsulated cement based piezoelectric sensor is developed and its working performance is verified. The consistency of the finite element simulation and the experimental results shows the feasibility of monitoring the corrosion of steel bars using encapsulated piezoelectric sensors. The research results show that the corrosion conditions of the steel bars can be determined by the relative amplitude of the measured signal through the encapsulated piezoelectric sensor.

  4. Encapsulation of dye molecules into mesoporous polymer resin and mesoporous polymer-silica films by an evaporation-induced self-assembly method

    Energy Technology Data Exchange (ETDEWEB)

    Chi Yue; Li Nan; Tu Jinchun; Zhang Yujie [School of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, Changchun 130012 (China); Li Xiaotian, E-mail: xiaotianli@jlu.edu.c [School of Material Science and Engineering, Key Laboratory of Automobile Materials of Ministry of Education, Jilin University, Changchun 130012 (China); Shao Changlu, E-mail: clshao@nenu.edu.c [Center for Advanced Optoelectronic Functional Materials Research, Northeast Normal University, Changchun 130024 (China)

    2010-03-15

    Polymer resin and polymer-silica films with highly ordered mesostructure have been used as host materials to encapsulate DCM (4-(dicyanomethylene) -2-methyl-6-(4-dimethylaminostyryl)-4h-pyran), a kind of fluorescent dye, through evaporation-induced self-assembly method (EISA). After encapsulation, the composites show significant blue-shift in photoluminescence (PL) spectra. Particularly, by changing the excitation wavelength, the samples show different emission bands. These phenomena are related to the mesostructure and the positions of DCM molecules in the host.

  5. Preliminary safety evaluation of a commercial-scale krypton-85 encapsulation facility

    International Nuclear Information System (INIS)

    Christensen, A.B.; Tanner, J.E.; Knecht, D.A.

    1980-01-01

    This paper demonstrates that a commercial-scale facility for encapsulating krypton-85 in zeolite-5A or glass at a 2000 MTHM per year nuclear fuel reprocessing plant can be designed to contain fragments and the 340 to 850 kCi krypton-85 inventory from an assumed catastrophic failure of the high pressure vessel. The vessel failure was assumed as a worst case and was not based on a detailed design evaluation or operating experience. The process design is based on existing commercial hot isostatic pressing technology operated at up to 40 times the scale required for krypton encapsulation. From the calculated process gas inventory in the pressure vessel and vessel design, the maximum explosive energy of 8.4 kg TNT and resulting vessel plug and fragment velocities were calculated. The facility Containment Cell housing the high pressure vessel was designed to contain the gases, fragments, and the shock wave energy calculated for a hypothetical vessel failure. The Access Cell located directly above the Containment Cell was designed to be a tertiary confinement of krypton-85, should the access hatch be breached. 3 figures, 2 tables

  6. Mixed Waste Salt Encapsulation Using Polysiloxane - Final Report

    International Nuclear Information System (INIS)

    Miller, C.M.; Loomis, G.G.; Prewett, S.W.

    1997-01-01

    A proof-of-concept experimental study was performed to investigate the use of Orbit Technologies polysiloxane grouting material for encapsulation of U.S. Department of Energy mixed waste salts leading to a final waste form for disposal. Evaporator pond salt residues and other salt-like material contaminated with both radioactive isotopes and hazardous components are ubiquitous in the DOE complex and may exceed 250,000,000 kg of material. Current treatment involves mixing low waste percentages (less than 10% by mass salt) with cement or costly thermal treatment followed by cementation to the ash residue. The proposed technology involves simple mixing of the granular salt material (with relatively high waste loadings-greater than 50%) in a polysiloxane-based system that polymerizes to form a silicon-based polymer material. This study involved a mixing study to determine optimum waste loadings and compressive strengths of the resultant monoliths. Following the mixing study, durability testing was performed on promising waste forms. Leaching studies including the accelerated leach test and the toxicity characteristic leaching procedure were also performed on a high nitrate salt waste form. In addition to this testing, the waste form was examined by scanning electron microscope. Preliminary cost estimates for applying this technology to the DOE complex mixed waste salt problem is also given

  7. Update on cellular encapsulation.

    Science.gov (United States)

    Smith, Kate E; Johnson, Robert C; Papas, Klearchos K

    2018-05-06

    There is currently a significant disparity between the number of patients who need lifesaving transplants and the number of donated human organs. Xenotransplantation is a way to address this disparity and attempts to enable the use of xenogeneic tissues have persisted for centuries. While immunologic incompatibilities have presented a persistent impediment to their use, encapsulation may represent a way forward for the use of cell-based xenogeneic therapeutics without the need for immunosuppression. In conjunction with modern innovations such as the use of bioprinting, incorporation of immune modulating molecules into capsule membranes, and genetic engineering, the application of xenogeneic cells to treat disorders ranging from pain to liver failure is becoming increasingly realistic. The present review discusses encapsulation in the context of xenotransplantation, focusing on the current status of clinical trials, persistent issues such as antigen shedding, oxygen availability, and donor selection, and recent developments that may address these limitations. © 2018 John Wiley & Sons A/S. Published by John Wiley & Sons Ltd.

  8. Encapsulation and retention of chelated-copper inside hydrophobic nanoparticles

    DEFF Research Database (Denmark)

    Hervella, Pablo; Ortiz, Elisa Parra; Needham, David

    2016-01-01

    ) Chelate copper into the octaethyl porphyrin; (3) Encapsulate OEP-Cu in nanoparticles: the encapsulation efficiency of copper into liquid nanoparticles (LNP), solid nanoparticles (SNP) and phospholipid liposomes (PL) was evaluated by UV-Vis and atomic absorption spectroscopy; (4) Retain the encapsulated...... OEP-Cu in the liquid or solid cores of the nanoparticles in the presence of a lipid sink. RESULTS: (1) The size of the nanoparticles was found to be strongly dependent on the Reynolds number and the initial concentration of components for the fast injection technique. At high Reynolds number (2181......), a minimum value for the particle diameter of ∼30nm was measured. (2) Copper was chelated by OEP in a 1:1mol ratio with an association constant of 2.57×10(5)M(-1). (3) The diameter of the nanoparticles was not significantly affected by the presence of OEP or OEP-Cu. The percentage of encapsulation of copper...

  9. Novel technology development through thermal drying of encapsulated Kluyveromyces marxianus in micro- and nano-tubular cellulose in lactose fermentation and its evaluation for food production.

    Science.gov (United States)

    Papapostolou, Harris; Servetas, Yiannis; Bosnea, Loulouda A; Kanellaki, Maria; Koutinas, Athanasios A

    2012-12-01

    A novel technology development based on the production of a low-cost starter culture for ripening of cheeses and baking is reported in the present study. The starter culture comprises thermally dried cells of Kluyveromyces marxianus encapsulated in micro- and nano-tubular cellulose. For production of a low-cost and effective biocatalyst, whey was used as raw material for biomass production and thermal drying methods (convective, conventional, and vacuum) were applied and evaluated at drying temperatures ranging from 35 to 60 °C. The effect of drying temperature of biocatalysts on fermentability of lactose and whey was evaluated. Storage stability and suitability of biocatalysts as a commercial starter cultures was also assessed and evaluated. All thermally dried biocatalysts were found to be active in lactose and whey fermentation. In all cases, there was sugar conversion ranging from 92 to 100 %, ethanol concentration of up to 1.47 % (v/v), and lactic acid concentrations ranged from 4.1 to 5.5 g/l. However, convective drying of the encapsulated cells of K. marxianus in micro- and nano-tubular cellulose was faster and a more effective drying method while drying at 42 °C appear to be the best drying temperature in terms of cell activity, ethanol, and lactic acid formation. Storage of the biocatalysts for 3 months at 4 °C proved maintenance of its activity even though fermentation times increased by 50-100 % compared with the fresh dried ones.

  10. Revision of Import and Export Requirements for Controlled Substances, Listed Chemicals, and Tableting and Encapsulating Machines, Including Changes To Implement the International Trade Data System (ITDS); Revision of Reporting Requirements for Domestic Transactions in Listed Chemicals and Tableting and Encapsulating Machines; and Technical Amendments. Final rule.

    Science.gov (United States)

    2016-12-30

    The Drug Enforcement Administration is updating its regulations for the import and export of tableting and encapsulating machines, controlled substances, and listed chemicals, and its regulations relating to reports required for domestic transactions in listed chemicals, gamma-hydroxybutyric acid, and tableting and encapsulating machines. In accordance with Executive Order 13563, the Drug Enforcement Administration has reviewed its import and export regulations and reporting requirements for domestic transactions in listed chemicals (and gamma-hydroxybutyric acid) and tableting and encapsulating machines, and evaluated them for clarity, consistency, continued accuracy, and effectiveness. The amendments clarify certain policies and reflect current procedures and technological advancements. The amendments also allow for the implementation, as applicable to tableting and encapsulating machines, controlled substances, and listed chemicals, of the President's Executive Order 13659 on streamlining the export/import process and requiring the government-wide utilization of the International Trade Data System (ITDS). This rule additionally contains amendments that implement recent changes to the Controlled Substances Import and Export Act (CSIEA) for reexportation of controlled substances among members of the European Economic Area made by the Improving Regulatory Transparency for New Medical Therapies Act. The rule also includes additional substantive and technical and stylistic amendments.

  11. Imaging features of encapsulating peritoneal sclerosis in continuous ambulatory peritoneal dialysis patients.

    LENUS (Irish Health Repository)

    Ti, Joanna P

    2010-07-01

    OBJECTIVE: The purpose of this article is to present the spectrum of radiologic findings of encapsulating peritoneal sclerosis in patients undergoing continuous ambulatory peritoneal dialysis (CAPD). CONCLUSION: Although a rare diagnosis, encapsulating peritoneal sclerosis in patients undergoing CAPD has a high morbidity and mortality. Diagnosis is often delayed because clinical features are insidious and nonspecific. Radiologic imaging may be helpful in the early diagnosis of encapsulating peritoneal sclerosis and in facilitating timely intervention for CAPD patients with encapsulating peritoneal sclerosis.

  12. High Resolution NMR Studies of Encapsulated Proteins In Liquid Ethane

    Science.gov (United States)

    Peterson, Ronald W.; Lefebvre, Brian G.; Wand, A. Joshua

    2005-01-01

    Many of the difficulties presented by large, aggregation-prone, and membrane proteins to modern solution NMR spectroscopy can be alleviated by actively seeking to increase the effective rate of molecular reorientation. An emerging approach involves encapsulating the protein of interest within the protective shell of a reverse micelle, and dissolving the resulting particle in a low viscosity fluid, such as the short chain alkanes. Here we present the encapsulation of proteins with high structural fidelity within reverse micelles dissolved in liquid ethane. The addition of appropriate co-surfactants can significantly reduce the pressure required for successful encapsulation. At these reduced pressures, the viscosity of the ethane solution is low enough to provide sufficiently rapid molecular reorientation to significantly lengthen the spin-spin NMR relaxation times of the encapsulated protein. PMID:16028922

  13. Micro-Encapsulation of non-aqueous solvents for energy-efficient carbon capture

    Energy Technology Data Exchange (ETDEWEB)

    Stolaroff, Joshua K; Ye, Congwang; Oakdale, James [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Baker, Sarah; Nugyen, Du; Smith, William; Aines, Roger

    2016-11-14

    Here, we demonstrate micro-encapsulation of several promising designer solvents: an IL, PCIL, and CO2BOL. We develop custom polymers that cure by UV light in the presence of each solvent while maintaining high CO2 permeability. We use several new process strategies to accommodate the viscosity and phase changes. We then measure and compare the CO2 absorption rate and capacity as well as the multi-cycle performance of the encapsulated solvents. These results are compared with previous work on encapsulated sodium carbonate solution. The prospects for designer solvents to reduce the cost of post-combustion capture and the implications for process design with encapsulated solvents are discussed.

  14. Antibody-integrated and functionalized graphite-encapsulated magnetic beads, produced using ammonia gas plasma technology, for capturing Salmonella.

    Science.gov (United States)

    Sakudo, Akikazu; Chou, Han; Nagatsu, Masaaki

    2015-03-01

    Salmonella spp. is the single and most important causative agent of foodborne infections, especially involving foods such as eggs, milk and meat. To prevent infection, a reliable surveillance system is required that can quickly and sensitively detect Salmonella. Here, we describe the development of antibody-integrated magnetic beads that are functionalized by a novel strategy using ammonia gas plasma. Ammonia plasma, produced by a radio frequency (RF) power supply, was allowed to react with the surface of graphite-encapsulated magnetic beads, resulting in the introduction of amino groups. An anti-Salmonella antibody was then anchored by sulfide groups present on the protein surface to the amino groups of the magnetic beads via N-succinimidyl 3-(2-pyridyldithio) propionate (SPDP). The potential usefulness of these magnetic beads for capturing Salmonella was examined as follows. The beads were incubated with Salmonella in liquid medium and then separated from the supernatant by applying a magnetic field. After thorough washing, adsorption of Salmonella to the beads was confirmed by immunochromatography, polymerase chain reaction and a direct culture assay. Our findings indicate that the capture and concentration of Salmonella using the antibody-integrated magnetic beads was more efficient than commercial Dynabeads® anti-Salmonella, which are conventionally used for concentrating Salmonella from liquid cultures. We believe this novel bead technology will contribute to the enhanced detection of Salmonella. Copyright © 2015 Elsevier Ltd. All rights reserved.

  15. Encapsulation of probiotic Bifidobacterium longum BIOMA 5920 with alginate-human-like collagen and evaluation of survival in simulated gastrointestinal conditions.

    Science.gov (United States)

    Su, Ran; Zhu, Xiao-Li; Fan, Dai-Di; Mi, Yu; Yang, Chan-Yuan; Jia, Xin

    2011-12-01

    Alginate (ALg)-human-like collagen (HLC) microspheres were prepared by the technology of electrostatic droplet generation in order to develop a biocompatible vehicle for probiotic bacteria. Microparticles were spherical with mean particle size of 400μm. The encapsulation efficiency (EE) of ALg-HLC microspheres could reach 92-99.2%. Water-soluble and fibrous human-like collagen is combined with sodium alginate through intermolecular hydrogen bonding and electrostatic force which were investigated by Fourier transform infrared spectroscopy (FTIR) and differential scanning calorimetry (DSC), thus the matrix of ALg-HLC was very stable. Bifidobacterium longum BIOMA 5920, as a kind of probiotic bacteria, was encapsulated with alginate-human-like collagen to survive and function in simulated gastrointestinal juice. Microparticles were very easy to degradation in simulated intestinal juices. After incubation in simulated gastric (pH 2.0, 2h), the encapsulated B. longum BIOMA 5920 numbers were 4.81 ± 0.38 log cfu/g. Copyright © 2011 Elsevier B.V. All rights reserved.

  16. Conformally encapsulated multi-electrode arrays with seamless insulation

    Energy Technology Data Exchange (ETDEWEB)

    Tabada, Phillipe J.; Shah, Kedar G.; Tolosa, Vanessa; Pannu, Satinderall S.; Tooker, Angela; Delima, Terri; Sheth, Heeral; Felix, Sarah

    2016-11-22

    Thin-film multi-electrode arrays (MEA) having one or more electrically conductive beams conformally encapsulated in a seamless block of electrically insulating material, and methods of fabricating such MEAs using reproducible, microfabrication processes. One or more electrically conductive traces are formed on scaffold material that is subsequently removed to suspend the traces over a substrate by support portions of the trace beam in contact with the substrate. By encapsulating the suspended traces, either individually or together, with a single continuous layer of an electrically insulating material, a seamless block of electrically insulating material is formed that conforms to the shape of the trace beam structure, including any trace backings which provide suspension support. Electrical contacts, electrodes, or leads of the traces are exposed from the encapsulated trace beam structure by removing the substrate.

  17. Encapsulation plant preliminary design, phase 2. Repository connected facility

    International Nuclear Information System (INIS)

    Kukkola, T.

    2006-12-01

    The disposal facility of the spent nuclear fuel will be located in Olkiluoto. The encapsulation plant is a part of the disposal facility. In this report, an independent encapsulation plant is located above the underground repository. In the encapsulation plant, the spent fuel is received and treated for disposal. In the fuel handling cell, the spent fuel assemblies are unloaded from the spent fuel transport casks and loaded into the disposal canisters. The gas atmosphere of the disposal canister is changed, the bolted inner canister lid is closed, and the electron beam welding method is used to close the lid of the outer copper canister. The disposal canisters are cleaned and transferred into the buffer store after the machining and inspection of the copper lid welds. From the buffer store, the disposal canisters are transferred into the repository spaces by help of the canister lift. All needed stages of operation are to be performed safely without any activity releases or remarkable personnel doses. The bentonite block interim storage is associated with the encapsulation plant. The bentonite blocks are made from bentonite powder. The bentonite blocks are used as buffer material around the disposal canister in the deposition hole. The average production rate of the encapsulation plant is 40 canisters per year. The nominal maximum production capacity is 100 canisters per year in one shift operation. (orig.)

  18. Encapsulation of ionic electroactive polymers: reducing the interaction with environment

    Science.gov (United States)

    Jaakson, P.; Aabloo, A.; Tamm, T.

    2016-04-01

    Ionic electro-active polymer (iEAP) actuators are composite materials that change their mechanical properties in response to external electrical stimulus. The interest in these devices is mainly driven by their capability to generate biomimetic movements, and their potential use in soft robotics. The driving voltage of an iEAP-actuator (0.5… 3 V) is at least an order of magnitude lower than that needed for other types of electroactive polymers. To apply iEAP-actuators in potential real-world applications, the capability of operating in different environments (open air, different solvents) must be available. In their natural form, the iEAP-actuators are capable of interacting with the surrounding environment (evaporation of solvent from the electrolyte solution, ion or solvent exchange, humidity effects), therefore, for prevention of unpredictable behavior of the actuator and the contamination of the environment, encapsulation of the actuator is needed. The environmental contamination aspect of the encapsulation material is substantial when selecting an applicable encapsulant. The suitable encapsulant should form thin films, be light in weight, elastic, fit tightly, low cost, and easily reproducible. The main goal of the present study is to identify and evaluate the best potential encapsulation techniques for iEAPactuators. Various techniques like thin film on liquid coating, dip coating, hot pressing, hot rolling; and several materials like polydimethylsiloxane, polyurethane, nitrocellulose, paraffin-composite-films were investigated. The advantages and disadvantages of the combinations of the above mentioned techniques and materials are discussed. Successfully encapsulated iEAP-actuators gained durability and were stably operable for long periods of time under ambient conditions. The encapsulation process also increased the stability of the iEAP-actuator by minimizing the environment effects. This makes controlling iEAP-actuators more straight-forward and

  19. Fabrication of hemispherical liquid encapsulated structures based on droplet molding

    Science.gov (United States)

    Ishizuka, Hiroki; Miki, Norihisa

    2015-12-01

    We have developed and demonstrated a method for forming spherical structures of a thin polydimethylsiloxane (PDMS) membrane encapsulating a liquid. Liquid encapsulation can enhance the performance of microelectromechanical systems (MEMS) devices by providing deformability and improved dielectric properties. Parylene deposition and wafer bonding are applied to encapsulate liquid into a MEMS device. In parylene deposition, a parylene membrane is directly formed onto a liquid droplet. However, since the parylene membrane is stiff, the membrane is fragile. Although wafer bonding can encapsulate liquid between two substrates, the surface of the fabricated structure is normally flat. We propose a new liquid encapsulation method by dispensing liquid droplets. At first, a 20 μl PDMS droplet is dispensed on ethylene glycol. A 70 μl glycerin droplet is dispensed into a PDMS casting solution layer. The droplet forms a layer on heated ethylene glycol. Glycerin and ethylene glycol are chosen for their high boiling points. Additionally, a glycerin droplet is dispensed on the layer and surrounded by a thin PDMS casting solution film. The film is baked for 1 h at 75 °C. As the result, a structure encapsulating a liquid in a flexible PDMS membrane is obtained. We investigate the effects of the volume, surface tension, and guide thickness on the shape of the formed structures. We also evaluated the effect of the structure diameter on miniaturization. The structure can be adapted for various functions by changing the encapsulated liquid. We fabricated a stiffness-tunable structure by dispensing a magnetorheoligical fluid droplet with a stiffness that can be changed by an external magnetic field. We also confirmed that the proposed structure can produce stiffness differences that are distinguishable by humans.

  20. It's a wrap: encapsulation as a management tool for marine biofouling.

    Science.gov (United States)

    Atalah, Javier; Brook, Rosemary; Cahill, Patrick; Fletcher, Lauren M; Hopkins, Grant A

    2016-01-01

    Encapsulation of fouled structures is an effective tool for countering incursions by non-indigenous biofoulers. However, guidelines for the implementation of encapsulation treatments are yet to be established. This study evaluated the effects of temperature, biomass, community composition, treatment duration and the biocide acetic acid on biofoulers. In laboratory trials using the model organisms Ciona spp. and Mytilus galloprovincialis, increasing the temperature or biomass speeded up the development of a toxic environment. Total mortality for Ciona spp. occurred within 72 and 24 h at 10 and 19°C, respectively. M. galloprovincialis survived up to 18 days, with high biomass increasing mortality at 10°C only. In a field study, three-month-old and four-year-old communities were encapsulated with and without acetic acid. Mortality took up to 10 days for communities encapsulated without acetic acid, compared to 48 h with acetic acid. The insights gained from this study will be useful in developing standardised encapsulation protocols.

  1. Modeling an array of encapsulated germanium detectors

    International Nuclear Information System (INIS)

    Kshetri, R

    2012-01-01

    A probability model has been presented for understanding the operation of an array of encapsulated germanium detectors generally known as composite detector. The addback mode of operation of a composite detector has been described considering the absorption and scattering of γ-rays. Considering up to triple detector hit events, we have obtained expressions for peak-to-total and peak-to-background ratios of the cluster detector, which consists of seven hexagonal closely packed encapsulated HPGe detectors. Results have been obtained for the miniball detectors comprising of three and four seven hexagonal closely packed encapsulated HPGe detectors. The formalism has been extended to the SPI spectrometer which is a telescope of the INTEGRAL satellite and consists of nineteen hexagonal closely packed encapsulated HPGe detectors. This spectrometer comprises of twelve detector modules surrounding the cluster detector. For comparison, we have considered a spectrometer comprising of nine detector modules surrounding the three detector configuration of miniball detector. In the present formalism, the operation of these sophisticated detectors could be described in terms of six probability amplitudes only. Using experimental data on relative efficiency and fold distribution of cluster detector as input, the fold distribution and the peak-to-total, peak-to-background ratios have been calculated for the SPI spectrometer and other composite detectors at 1332 keV. Remarkable agreement between experimental data and results from the present formalism has been observed for the SPI spectrometer.

  2. Nanoprecipitation process: From encapsulation to drug delivery.

    Science.gov (United States)

    Martínez Rivas, Claudia Janeth; Tarhini, Mohamad; Badri, Waisudin; Miladi, Karim; Greige-Gerges, Hélène; Nazari, Qand Agha; Galindo Rodríguez, Sergio Arturo; Román, Rocío Álvarez; Fessi, Hatem; Elaissari, Abdelhamid

    2017-10-30

    Drugs encapsulation is a suitable strategy in order to cope with the limitations of conventional dosage forms such as unsuitable bioavailability, stability, taste, and odor. Nanoprecipitation technique has been used in the pharmaceutical and agricultural research as clean alternative for other drug carrier formulations. This technique is based on precipitation mechanism. Polymer precipitation occurs after the addition of a non-solvent to a polymer solution in four steps mechanism: supersaturation, nucleation, growth by condensation, and growth by coagulation that leads to the formation of polymer nanoparticles or aggregates. The scale-up of laboratory-based nanoprecipitation method shows a good reproducibility. In addition, flash nanoprecipitation is a good strategy for industrial scale production of nanoparticles. Nanoprecipitation is usually used for encapsulation of hydrophobic or hydrophilic compounds. Nanoprecipitation was also shown to be a good alternative for the encapsulation of natural compounds. As a whole, process and formulation related parameters in nanoprecipitation technique have critical effect on nanoparticles characteristics. Biodegradable or non-biodegradable polymers have been used for the preparation of nanoparticles intended to in vivo studies. Literature studies have demonstrated the biodistribution of the active loaded nanoparticles in different organs after administration via various routes. In general, in vitro drug release from nanoparticles prepared by nanoprecipitation includes two phases: a first phase of "burst release" which is followed by a second phase of prolonged release. Moreover, many encapsulated active molecules have been commercialized in the pharmaceutical market. Copyright © 2017 Elsevier B.V. All rights reserved.

  3. The interaction of encapsulated pharmaceutical drugs with a silica matrix.

    Science.gov (United States)

    Morais, Everton C; Correa, Gabriel G; Brambilla, Rodrigo; Radtke, Claudio; Baibich, Ione Maluf; dos Santos, João Henrique Z

    2013-03-01

    A series of seven drugs, namely, fluoxetine, gentamicin, lidocaine, morphine, nifedipine, paracetamol and tetracycline, were encapsulated. The encapsulated systems were characterized using a series of complementary techniques: Fourier-transform infrared spectroscopy (FT-IR), diffusive reflectance spectroscopy in the UV-vis region (DRS) and X-ray photoelectron spectroscopy (XPS). According to the DRS spectra, most of the encapsulated systems showed a band shift of the maximum absorption when compared with the corresponding bare pharmaceutical. Additionally, after encapsulation, the drugs exhibited infrared band shifts toward higher wavenumbers, which in turn provided insight into potential sites for interaction with the silica framework. The amine group showed a band shift in the spectra of almost all the drugs (except nifedipine and tetracycline). This finding indicates the possibility of a hydrogen bonding interaction between the drug and the silica via electron donation from the amine group to the silica framework. XPS confirmed this interaction between the pharmaceuticals and the silica through the amine group. A correlation was observed between the textural characteristics of the solids and the spectroscopic data, suggesting that the amine groups from the pharmaceuticals were more perturbed upon encapsulation. Copyright © 2012 Elsevier B.V. All rights reserved.

  4. Encapsulation of cosmetic active ingredients for topical application--a review.

    Science.gov (United States)

    Casanova, Francisca; Santos, Lúcia

    2016-02-01

    Microencapsulation is finding increasing applications in cosmetics and personal care markets. This article provides an overall discussion on encapsulation of cosmetically active ingredients and encapsulation techniques for cosmetic and personal care products for topical applications. Some of the challenges are identified and critical aspects and future perspectives are addressed. Many cosmetics and personal care products contain biologically active substances that require encapsulation for increased stability of the active materials. The topical and transdermal delivery of active cosmetic ingredients requires effective, controlled and safe means of reaching the target site within the skin. Preservation of the active ingredients is also essential during formulation, storage and application of the final cosmetic product. Microencapsulation offers an ideal and unique carrier system for cosmetic active ingredients, as it has the potential to respond to all these requirements. The encapsulated agent can be released by several mechanisms, such as mechanical action, heat, diffusion, pH, biodegradation and dissolution. The selection of the encapsulation technique and shell material depends on the final application of the product, considering physical and chemical stability, concentration, required particle size, release mechanism and manufacturing costs.

  5. The improved stability of enzyme encapsulated in biomimetic titania particles

    International Nuclear Information System (INIS)

    Jiang Yanjun; Sun Qianyun; Jiang Zhongyi; Zhang Lei; Li Jian; Li Lin; Sun Xiaohui

    2009-01-01

    This study demonstrates a novel biomimetic approach for the entrapment of yeast alcohol dehydrogenase (YADH) within titania nanoparticles to improve its stability. Protamine was as the template and catalyst for the condensation of titanium (IV) bis(ammonium lactato) dihydroxide (Ti-BALDH) into titania nanoparticles in which YADH was trapped. The as-prepared titania/protamine/YADH composites were characterized by scanning electron microscopy (SEM), transmission electron microscopy (TEM), dynamic light scattering (DLS), X-ray powder diffraction (XRD) and X-ray photoelectron spectroscopy (XPS). The mechanism of YADH encapsulation was tentatively proposed from a series of experimental results. The preliminary investigation showed that encapsulated YADH could retain most of its initial activity. Compared to free YADH, encapsulated YADH exhibited significantly improved thermal, pH and recycling stability. After 5 weeks storage, no substantial loss of catalytic activity for encapsulated YADH was observed

  6. Enhanced function of immuno-isolated islets in diabetes therapy by co-encapsulation with an anti-inflammatory drug.

    Science.gov (United States)

    Dang, Tram T; Thai, Anh V; Cohen, Joshua; Slosberg, Jeremy E; Siniakowicz, Karolina; Doloff, Joshua C; Ma, Minglin; Hollister-Lock, Jennifer; Tang, Katherine M; Gu, Zhen; Cheng, Hao; Weir, Gordon C; Langer, Robert; Anderson, Daniel G

    2013-07-01

    Immuno-isolation of islets has the potential to enable the replacement of pancreatic function in diabetic patients. However, host response to the encapsulated islets frequently leads to fibrotic overgrowth with subsequent impairment of the transplanted grafts. Here, we identified and incorporated anti-inflammatory agents into islet-containing microcapsules to address this challenge. In vivo subcutaneous screening of 16 small molecule anti-inflammatory drugs was performed to identify promising compounds that could minimize the formation of fibrotic cell layers. Using parallel non-invasive fluorescent and bioluminescent imaging, we identified dexamethasone and curcumin as the most effective drugs in inhibiting the activities of inflammatory proteases and reactive oxygen species in the host response to subcutaneously injected biomaterials. Next, we demonstrated that co-encapsulating curcumin with pancreatic rat islets in alginate microcapsules reduced fibrotic overgrowth and improved glycemic control in a mouse model of chemically-induced type I diabetes. These results showed that localized administration of anti-inflammatory drug can improve the longevity of encapsulated islets and may facilitate the translation of this technology toward a long-term cure for type I diabetes. Published by Elsevier Ltd.

  7. Encapsulated phosphates reduce lipid oxidation in both ground chicken and ground beef during raw and cooked meat storage with some influence on color, pH, and cooking loss.

    Science.gov (United States)

    Kılıç, B; Simşek, A; Claus, J R; Atılgan, E

    2014-05-01

    Effects of encapsulated sodium tripolyphosphate (STP), sodium hexametaphosphate (HMP) and sodium pyrophosphate (SPP) on lipid oxidation in uncooked (0, 2, 24h) and cooked (0, 1, 7 d) ground chicken and beef during storage were determined. Ten phosphate treatments included a control (no phosphate), three unencapsulated (u) at 0.5% and three encapsulated (e) phosphates (0.5%) each at a low (e-low) and high (e-high) coating level. Two heating rates (slow, fast) were investigated. Cooking loss (CL), pH, color, orthophosphate (OP), TBARS and lipid hydroperoxides (LPO) were determined. A fast heating and uSTP resulted in lower CL (pcooked samples. Not increased coating level but encapsulated phosphates decreased lipid oxidation in cooked samples (p<0.05). Copyright © 2014 Elsevier Ltd. All rights reserved.

  8. Safety evaluation for packaging (onsite) singly encapsulated cesium chloride capsules

    International Nuclear Information System (INIS)

    Smyth, W.W.

    1997-01-01

    Three nonstandard Waste Encapsulation and Storage Facility (WESF) cesium chloride capsules are being shipped from WESF (225B building) to the 324 building. They would normally be shipped in the Beneficial Uses Shipping System (BUSS) cask under its US Department of Energy (DOE) license (DOE 1996), but these capsules are nonstandard: one has a damaged or defective weld in the outer layer of encapsulation, and two have the outer encapsulation removed. The 3 capsules, along with 13 other capsules, will be overpacked in the 324 building to meet the requirements for storage in WESF's pool

  9. Quantification of encapsulated bioburden in spacecraft polymer materials by cultivation-dependent and molecular methods.

    Directory of Open Access Journals (Sweden)

    Anja Bauermeister

    Full Text Available Bioburden encapsulated in spacecraft polymers (such as adhesives and coatings poses a potential risk to jeopardize scientific exploration of other celestial bodies. This is particularly critical for spacecraft components intended for hard landing. So far, it remained unclear if polymers are indeed a source of microbial contamination. In addition, data with respect to survival of microbes during the embedding/polymerization process are sparse. In this study we developed testing strategies to quantitatively examine encapsulated bioburden in five different polymers used frequently and in large quantities on spaceflight hardware. As quantitative extraction of the bioburden from polymerized (solid materials did not prove feasible, contaminants were extracted from uncured precursors. Cultivation-based analyses revealed <0.1-2.5 colony forming units (cfu per cm3 polymer, whereas quantitative PCR-based detection of contaminants indicated considerably higher values, despite low DNA extraction efficiency. Results obtained from this approach reflect the most conservative proxy for encapsulated bioburden, as they give the maximum bioburden of the polymers irrespective of any additional physical and chemical stress occurring during polymerization. To address the latter issue, we deployed an embedding model to elucidate and monitor the physiological status of embedded Bacillus safensis spores in a cured polymer. Staining approaches using AlexaFluor succinimidyl ester 488 (AF488, propidium monoazide (PMA, CTC (5-cyano-2,3-diotolyl tetrazolium chloride demonstrated that embedded spores retained integrity, germination and cultivation ability even after polymerization of the adhesive Scotch-Weld 2216 B/A. Using the methods presented here, we were able to estimate the worst case contribution of encapsulated bioburden in different polymers to the bioburden of spacecraft. We demonstrated that spores were not affected by polymerization processes. Besides Planetary

  10. Suitability of cement encapsulated ILW for transport

    International Nuclear Information System (INIS)

    Fitzpatrick, J.

    1989-01-01

    ILW arising during the reprocessing of nuclear fuel is to be encapsulated in cement in nominal 500-litre drums. It is important that the waste package produced can be safely transported to a deep repository. Preliminary assessments of the performances of waste packages during transport for a number of the ILW streams to be generated at Sellafield have been carried out. The results show that the proposed encapsulation process produces a waste package which can be transported to an acceptable standard of safety and which does not prejudice any aspects of transport. (author)

  11. A Comparative Cytotoxic Evaluation of Disulfiram Encapsulated PLGA Nanoparticles on MCF-7 Cells.

    Science.gov (United States)

    Fasehee, Hamidreza; Ghavamzadeh, Ardeshir; Alimoghaddam, Kamran; Ghaffari, Seyed-Hamidollah; Faghihi, Shahab

    2017-04-01

    Background: Disulfiram is oral aldehyde dehydrogenase (ALDH) inhibitor that has been used in the treatment of alcoholism. Recent studies show that this drug has anticancer properties; however, its rapid degradation has limited its clinical application. Encapsulation of disulfiram polymeric nanoparticles (NPs) may improve its anticancer activities and protect rapid degradation of the drug. Materials and Methods: A poly (lactide-co-Glycolide) (PLGA) was developed for encapsulation of disulfiram and its delivery into breast cancer cells. Disulfiram encapsulated PLGA NPs were prepared by nanoprecipitation method and were characterized by Scanning Electron Microscopy (SEM). The loading and encapsulation efficiency of NPs were determined using UV-Visible spectroscopy. Cell cytotoxicity of free and encapsulated form of disulfiram is also determined using MTT assay. Results: Disulfiram encapsulated PLGA NPs had uniform size with 165 nm. Drug loading and entrapment efficiency were 5.35 ±0.03% and 58.85±1.01%. The results of MTT assay showed that disulfiram encapsulated PLGA NPs were more potent in induction of apoptosis compare to free disulfiram. Conclusion: Based on the results obtained in the present study it can be concluded that encapsulation of disulfiram with PLGA can protect its degradation in improve its cytotoxicity on breast cancer cells.

  12. Mechanical Robustness and Hermeticity Monitoring for MEMS Thin Film Encapsulation

    NARCIS (Netherlands)

    Santagata, F.

    2011-01-01

    Many Micro-Electro-Mechanical-Systems (MEMS) require encapsulation, to prevent delicate sensor structures being exposed to external perturbations such as dust, humidity, touching, and gas pressure. An upcoming and cost-effective way of encapsulation is zero-level packaging or thin-film

  13. Postmortem analysis of encapsulation around long-term ventricular endocardial pacing leads.

    Science.gov (United States)

    Candinas, R; Duru, F; Schneider, J; Lüscher, T F; Stokes, K

    1999-02-01

    To analyze the site and thickness of encapsulation around ventricular endocardial pacing leads and the extent of tricuspid valve adhesion, from today's perspective, with implications for lead removal and sensor location. Gross cardiac postmortem analysis was performed in 11 cases (8 female and 3 male patients; mean age, 78+/-7 years). None of the patients had died because of pacemaker malfunction. The mean implant time was 61+/-60 months (range, 4 to 184). The observations ranged from encapsulation only at the tip of the pacing lead to complete encapsulation along the entire length of the pacing lead within the right ventricle. Substantial areas of adhesion at the tricuspid valve apparatus were noted in 7 of the 11 cases (64%). The firmly attached leads could be removed only by dissection, and in some cases, removal was possible only by damaging the associated structures. No specific optimal site for sensor placement could be identified along the ventricular portion of the pacing leads; however, the fibrotic response was relatively less prominent in the atrial chamber. Extensive encapsulation is present in most long-term pacemaker leads, which may complicate lead removal. The site and thickness of encapsulation seem to be highly variable. Tricuspid valve adhesion, which is usually underestimated, may be severe. In contrast to earlier reports, our study demonstrates that the extent of fibrotic encapsulation may not be related to the duration since lead implantation. Moreover, we noted no ideal encapsulation-free site for sensors on the ventricular portion of long-term pacing leads.

  14. Titanium dioxide encapsulation of supported Ag nanoparticles on the porous silica bead for increased photocatalytic activity

    International Nuclear Information System (INIS)

    Liu, Hui; Deng, Lu; Sun, Chaochao; Li, Junqi; Zhu, Zhenfeng

    2015-01-01

    Graphical abstract: - Highlights: • A novel Ag-loading and TiO 2 -coating technique was used to prepare samples. • The photocatalytic activity of the product was evaluated by removing of Rh B. • The as-synthesized samples showed an excellent photocatalytic activity. - Abstract: A new synthetic strategy has been developed to encapsulate Ag nanoparticles in heterogeneous catalysts to prevent their dropping and sintering. Ag nanoparticles with diameters about 5–10 nm were first supported on the porous silica bead. These were then covered with a fresh layer of titanium dioxide with the thickness about 5 nm. SEM and TEM images were used to confirm the success of each synthesis step, and the photocatalytic activity of the as-synthesized samples was evaluated by photocatalytic decolorization of Rhodamine B (Rh B) aqueous solution at ambient temperature under both UV and visible light irradiation. The resulting titanium dioxide encapsulated Ag nanoparticles exhibited an enhanced photocatalytic activity under both UV and visible light irradiation, this can be attributed to effective charge separation and light harvesting of the plasmonic silver nanoparticles decoration, even the reducing of the exciton recombination rate caused by the small grain size of anatase TiO 2 nanocrystals

  15. Microemulsion synthesis and magnetic properties of hydroxyapatite-encapsulated nano CoFe{sub 2}O{sub 4}

    Energy Technology Data Exchange (ETDEWEB)

    Foroughi, Firoozeh [Department of Materials Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Isfahan (Iran, Islamic Republic of); Hassanzadeh-Tabrizi, S.A., E-mail: tabrizi1980@gmail.com [Young Researchers and Elite Club, Najafabad Branch, Islamic Azad University, Najafabad, Isfahan (Iran, Islamic Republic of); Amighian, Jamshid [Department of Materials Engineering, Najafabad Branch, Islamic Azad University, Najafabad, Isfahan (Iran, Islamic Republic of)

    2015-05-15

    Hydroxyapatite-encapsulated cobalt ferrite (CoFe{sub 2}O{sub 4}) nanopowders were synthesized by one step microemulsion method. The powders were characterized by X-ray Diffraction, Fourier transform infrared spectroscopy, field emission scanning electron microscopy, transmission electron microscopy and vibrating sample magnetometer. TEM results showed that nanoparticles calcined at 700 °C have core–shell morphology. It was found that the resultant phases, morphology and magnetic properties of the samples depend on calcining temperature. The synthesized nanoparticles showed a maximum saturation magnetization of 7.8 emu/g with a wasp-waisted hysteresis loop. The magnetion was reduced by increasing calcining temperature to 900 °C. This reduction is due to the reaction of cobalt ferrite with hydroxyapatite which leads to CaFe{sub 12}(PO{sub 4}){sub 8}(OH){sub 12} phase. - Highlights: • Hydroxyapatite-encapsulated cobalt ferrite nanopowders were synthesized by a microemulsion method. • The characterization of nanoparticles was performed using various analytical tools, such as TEM, FE-SEM, FTIR, XRD and VSM. • The nanoparticles showed a maximum saturation magnetization of 7.8 emu/g. • The samples indicated a wasp-waisted hysteresis loop.

  16. Swedish encapsulation station review

    International Nuclear Information System (INIS)

    Andersson, Sven Olof; Brunzell, P.; Heibel, R.; McCarthy, J.; Pennington, C.; Rusch, C.; Varley, G.

    1998-06-01

    In the Encapsulation Station (ES) Review performed by NAC International, a number of different areas have been studied. The main objectives with the review have been to: Perform an independent review of the cost estimates for the ES presented in SKB's document 'Plan 1996'. This has been made through comparisons between the ES and BNFL's Waste Encapsulation Plant (WEP) at Sellafield as well as with the CLAB facility. Review the location of the ES (at the CLAB site or at the final repository) and its interaction with other parts of the Swedish system for spent fuel management. Review the logistics and plant capacity of the ES. Identify important safety aspects of the ES as a basis for future licensing activities. Based on NAC International's experience of casks for transport and storage of spent fuel, review the basic design of the copper/steel canister and the transport cask. This review insides design, manufacturing, handling and licensing aspects. Perform an overall comparison between the ES project and the CLAB project with the objective to identify major project risks and discuss their mitigation

  17. Consumer Acceptance of Bars and Gummies with Unencapsulated and Encapsulated Resveratrol.

    Science.gov (United States)

    Koga, Clarissa C; Lee, Soo-Yeun; Lee, Youngsoo

    2016-05-01

    The addition of resveratrol, a polyphenol found in red wine and peanuts, to food products would help to provide the health benefits associated with the compound to the consumer in a wide array of food matrices. The bitterness of resveratrol and instability of its bioactive form in light are 2 major challenges with the incorporation of the compound into food products. Microencapsulation in a sodium caseinate matrix was utilized as a strategy to overcome these challenges. The objective of this research was to show the application of the resveratrol microcapsules in easy-to-consume foods. Consumer acceptance was evaluated for gummies and bars with encapsulated resveratrol in comparison to the controls. Four different controls were used: 1) without any resveratrol OR protein (Plain), 2) unencapsulated resveratrol (Resv), 3) sodium caseinate and unencapsulated resveratrol just mixed without encapsulation (P + R), and 4) sodium caseinate only (PRO). Two concentrations of resveratrol that have been shown to offer therapeutic effects in humans were tested (10 and 40 mg/d). The overall liking, evaluated using a 9-point scale, of bars with 10 mg of encapsulated resveratrol did not differ significantly from the control without any added resveratrol and protein (Plain) or from the controls with equivalent protein and/or resveratrol concentrations. For gummies, the samples with the resveratrol microcapsules had a significantly lower overall liking than the controls with the same protein and/or resveratrol content. This research demonstrated application of resveratrol microcapsules into easy-to-consume food products in order to deliver the health benefits to the consumer. © 2016 Institute of Food Technologists®

  18. Micelle-encapsulated fullerenes in aqueous electrolytes

    Energy Technology Data Exchange (ETDEWEB)

    Ala-Kleme, T., E-mail: timo.ala-kleme@utu.fi [Department of Chemistry, University of Turku, 20014 Turku (Finland); Maeki, A.; Maeki, R.; Kopperoinen, A.; Heikkinen, M.; Haapakka, K. [Department of Chemistry, University of Turku, 20014 Turku (Finland)

    2013-03-15

    Different micellar particles Mi(M{sup +}) (Mi=Triton X-100, Triton N-101 R, Triton CF-10, Brij-35, M{sup +}=Na{sup +}, K{sup +}, Cs{sup +}) have been prepared in different aqueous H{sub 3}BO{sub 3}/MOH background electrolytes. It has been observed that these particles can be used to disperse the highly hydrophobic spherical [60]fullerene (1) and ellipsoidal [70]fullerene (2). This dispersion is realised as either micelle-encapsulated monomers Mi(M{sup +})1{sub m} and Mi(M{sup +})2{sub m} or water-soluble micelle-bound aggregates Mi(M{sup +})1{sub agg} and Mi(M{sup +})2{sub agg}, where especially the hydration degree and polyoxyethylene (POE) thickness of the micellar particle seems to play a role of vital importance. Further, the encapsulation microenvironment of 1{sub m} was found to depend strongly on the selected monovalent electrolyte cation, i.e., the encapsulated 1{sub m} is accommodated in the more hydrophobic microenvironment the higher the cationic solvation number is. - Highlights: Black-Right-Pointing-Pointer Different micellar particles is used to disperse [60]fullerene and [70]fullerene. Black-Right-Pointing-Pointer Fullerene monomers or aggregates are dispersed encaging or bounding by micelles. Black-Right-Pointing-Pointer Effective facts are hydration degree and polyoxyethylene thickness of micelle.

  19. Encapsulation of polymer photovoltaic prototypes

    DEFF Research Database (Denmark)

    Krebs, Frederik C

    2006-01-01

    A simple and efficient method for the encapsulation of polymer and organic photovoltaic prototypes is presented. The method employs device preparation on glass substrates with subsequent sealing using glass fiber reinforced thermosetting epoxy (prepreg) against a back plate. The method allows...

  20. Encapsulation and Nano-Encapsulation of Papain Active Sites to Enhance Radiolityc Stability and Decrease Toxicity

    Energy Technology Data Exchange (ETDEWEB)

    Lugão, A. B.; Varca, G. H.C.; Mathor, M. B.; Santos Lopes, P.; Rogero, M. S.S.; Rogero, J.R., E-mail: ablugao@ipen.br [Comissão Nacional de Energia Nuclear (CNEN), Instituto de Pesquisas Energeticas e Nucleares (IPEN), Av. Prof. Lineu Prestes, 2242 Cidade Universitaria, 05508-000 Sao Paulo (Brazil)

    2010-07-01

    Papain is used as an ingredient in various enzymatic debridement preparations. Those paste-like preparations are based on water solution and usually are sterilized by radiation. As a consequence, there is a major decrease in papain activity. Papain containing preparations are used in chronic wounds treatment in order to clean and remove the necrotic tissue. However FDA (2008) is taking an action against such products due to severe adverse events reported in patients submitted to papain treatments. Thus, the main goal of this proposal is to develop encapsulated papain containing membranes based on hydrogels and silicone rubber in an attempt to achieve a controllable distribution of size and delivery profile, a toxicity reduction and provide stability towards radiation processing through molecular encapsulation with β-cyclodextrin, which may also provide protection to the enzyme against radiation induced radiolysis. (author)

  1. Encapsulation and Nano-Encapsulation of Papain Active Sites to Enhance Radiolityc Stability and Decrease Toxicity

    International Nuclear Information System (INIS)

    Lugão, A.B.; Varca, G.H.C.; Mathor, M.B.; Santos Lopes, P.; Rogero, M.S.S.; Rogero, J.R.

    2010-01-01

    Papain is used as an ingredient in various enzymatic debridement preparations. Those paste-like preparations are based on water solution and usually are sterilized by radiation. As a consequence, there is a major decrease in papain activity. Papain containing preparations are used in chronic wounds treatment in order to clean and remove the necrotic tissue. However FDA (2008) is taking an action against such products due to severe adverse events reported in patients submitted to papain treatments. Thus, the main goal of this proposal is to develop encapsulated papain containing membranes based on hydrogels and silicone rubber in an attempt to achieve a controllable distribution of size and delivery profile, a toxicity reduction and provide stability towards radiation processing through molecular encapsulation with β-cyclodextrin, which may also provide protection to the enzyme against radiation induced radiolysis. (author)

  2. Micro-encapsulation of refined olive oil: influence of capsule wall components and the addition of antioxidant additives on the shelf life and chemical alteration.

    Science.gov (United States)

    Calvo, Patricia; Castaño, Angel Luís; Lozano, Mercedes; González-Gómez, David

    2012-10-01

    Although refined olive oils (ROOs) exhibit lower quality and less stability toward thermal stress than extra-virgin olive oils, these types of oil are gaining importance in the food industry. The inclusion of ROOs in processed food may alter the oxidative stability of the manufactured products, and therefore having technological alternatives to increase oil stability will be an important achievement. For this reason the main goal of this study was to assess the influence of the micro-encapsulation process on the ROO chemical composition and its oxidative stability. Factors such as microcapsule wall constituents and the addition of the antioxidant butyl hydroxytoluene were investigated in order to establish the most appropriate conditions to ensure no alteration of the refined olive oil chemical characteristics. The optimised methodology exhibited high encapsulation yield (>98%), with micro-encapsulation efficiency ranging from 35 to 69% according to the nature of the wall components. The encapsulation process slightly altered the chemical composition of the olive oil and protected the oxidative stability for at least 11 months when protein components were included as wall components. It was concluded that the presence of proteins constituents in the microcapsule wall material extended the shelf life of the micro-encapsulated olive oil regardless the use of antioxidant additives. Copyright © 2012 Society of Chemical Industry.

  3. Increased encapsulated cell biodelivery of nerve growth factor in the brain by transposon-mediated gene transfer

    DEFF Research Database (Denmark)

    Fjord-Larsen, L; Kusk, Poul Henrik; Emerich, D F

    2012-01-01

    transposon expression technology to establish a new clinical grade cell line, NGC0211, with at least 10 times higher NGF production than that of NGC-0295. To test whether encapsulation of this cell line provides a relevant dose escalation step in delivering NGF for treatment of the cognitive decline in AD...... cases correlate with highly improved potency.Gene Therapy advance online publication, 24 November 2011; doi:10.1038/gt.2011.178....

  4. Antioxidant Effects of Quercetin and Catechin Encapsulated into PLGA Nanoparticles

    Directory of Open Access Journals (Sweden)

    Hector Pool

    2012-01-01

    Full Text Available Polymeric nanoparticles (PLGA have been developed for the encapsulation and controlled release of quercetin and catechin. Nanoparticles were fabricated using a solvent displacement method. Physicochemical properties were measured by light scattering, scanning electron microscopy and ζ-potential, X-ray diffraction, infrared spectroscopy and differential scanning calorimetry. Encapsulation efficiency and in vitro release profiles were obtained from differential pulse voltammetry experiments. Antioxidant properties of free and encapsulated flavonoids were determined by TBARS, fluorescence spectroscopy and standard chelating activity methods. Relatively small (d≈ 400 nm polymeric nanoparticles were obtained containing quercetin or catechin in a non-crystalline form (EE ≈ 79% and the main interactions between the polymer and each flavonoid were found to consist of hydrogen bonds. In vitro release profiles were pH-dependant, the more acidic pH, the faster release of each flavonoid from the polymeric nanoparticles. The inhibition of the action of free radicals and chelating properties, were also enhanced when quercetin and catechin were encapsulated within PLGA nanoparticles. The information obtained from this study will facilitate the design and fabrication of polymeric nanoparticles as possible oral delivery systems for encapsulation, protection and controlled release of flavonoids aimed to prevent oxidative stress in human body or food products.

  5. Encapsulation of lycopene in Chlorella pyrenoidosa: Loading properties and stability improvement.

    Science.gov (United States)

    Pu, Chuanfen; Tang, Wenting

    2017-11-15

    Aiming to improve the stability of lycopene and incorporate it into a complex nutraceutical, exogenous lycopene-loaded Chlorella pyrenoidosa cells (CPCs) were developed. The complex had an encapsulation yield of 13.06±0.89% and an encapsulation efficiency of 96.31±3.10%. Fluorescence analyses indicated that lycopene was encapsulated in the CPCs. X-ray diffraction, thermogravimetric and differential scanning calorimetric analyses were conducted and compared to those of the non-loaded CPCs, lycopene and their physical mixture. These studies demonstrated that lycopene was amorphous in the complex. The degradation kinetics indicated that encapsulation increased the stability of lycopene. The antioxidant activity of lycopene loaded CPCs against DPPH free radicals was higher than that of the unencapsulated lycopene after storage at 25°C for 25d. This study proved the feasibility of encapsulation of lycopene in the CPCs and combined the activities of both materials, which could be employed in the production of novel nutraceuticals to reduce oxidative stress. Copyright © 2017 Elsevier Ltd. All rights reserved.

  6. Fragrance encapsulation in polymeric matrices by emulsion electrospinning

    OpenAIRE

    Camerlo Agathe; Vebert-Nardin Corinne; Rossi René Michel; Popa Ana Maria

    2013-01-01

    We present the successful application of emulsion electrospinning for the encapsulation of a model for highly volatile fragrances namely (R) (+) limonene in a poly(vinyl alcohol) (PVA) fibrous matrix. The influence of the emulsion formulation and of its colloidal properties on the fiber morphology as well as on the limonene encapsulation efficiency is described. The release profile of the fragrance from the electrospun nanofibers over a fifteen days range shows that this type of nanofibrous m...

  7. Wafer-level vacuum/hermetic packaging technologies for MEMS

    Science.gov (United States)

    Lee, Sang-Hyun; Mitchell, Jay; Welch, Warren; Lee, Sangwoo; Najafi, Khalil

    2010-02-01

    An overview of wafer-level packaging technologies developed at the University of Michigan is presented. Two sets of packaging technologies are discussed: (i) a low temperature wafer-level packaging processes for vacuum/hermeticity sealing, and (ii) an environmentally resistant packaging (ERP) technology for thermal and mechanical control as well as vacuum packaging. The low temperature wafer-level encapsulation processes are implemented using solder bond rings which are first patterned on a cap wafer and then mated with a device wafer in order to encircle and encapsulate the device at temperatures ranging from 200 to 390 °C. Vacuum levels below 10 mTorr were achieved with yields in an optimized process of better than 90%. Pressures were monitored for more than 4 years yielding important information on reliability and process control. The ERP adopts an environment isolation platform in the packaging substrate. The isolation platform is designed to provide low power oven-control, vibration isolation and shock protection. It involves batch flip-chip assembly of a MEMS device onto the isolation platform wafer. The MEMS device and isolation structure are encapsulated at the wafer-level by another substrate with vertical feedthroughs for vacuum/hermetic sealing and electrical signal connections. This technology was developed for high performance gyroscopes, but can be applied to any type of MEMS device.

  8. Spent LWR fuel encapsulation and dry storage demonstration

    International Nuclear Information System (INIS)

    Bahorich, R.J.; Durrill, D.C.; Cross, T.E.; Unterzuber, R.

    1980-01-01

    In 1977 the Spent Fuel Handling and Packaging Program (SFHPP) was initiated by the Department of Energy to develop and test the capability to satisfactorily encapsulate typical spent fuel assemblies from commercial light-water nuclear power plants and to establish the suitability of one or more surface and near surface concepts for the interim dry storage of the encapsulated spent fuel assemblies. The E-MAD Facility at the Nevada Test Site, which is operated for the Department of Energy by the Advanced Energy Systems Division (AESD) of the Westinghouse Electric Corporation, was chosen as the location for this demonstration because of its extensive existing capabilities for handling highly radioactive components and because of the desirable site characteristics for the proposed storage concepts. This paper describes the remote operations related to the process steps of handling, encapsulating and subsequent dry storage of spent fuel in support of the Demonstration Program

  9. Encapsulation of biological species in sol-gel matrices

    International Nuclear Information System (INIS)

    Finnie, K.S.; Bartlett, J.R.; Woolfrey, J.L.

    2000-01-01

    Two examples are given of the gelation of silica sols containing bio catalysts, resulting in their encapsulation in porous matrices. Urease was encapsulated in gels made from a mixture of TMOS and alkyltrimethoxysilane. Enzyme activities, monitored by measuring the rate of production of ammoniacal nitrogen as urea was decomposed, ranged up to 60% of that of the unencapsulated species. Anaerobic sulphate-reducing bacteria were encapsulated in a gel produced from colloidal silica, thus avoiding contact with alcohol. The detection of H 2 S produced in the doped gel indicated that the bacteria were able to continue normal metabolic function within the gel matrix. A gel initially doped with ∼ 5 x 10 5 cells cm -3 , exhibited an optimum sulphate reduction rate of 11 ug h -1 cm -3 ; this reduction rate was quickly re-established after storage of the gel for 14 weeks. Copyright (2000) The Australian Ceramic Society

  10. The Advanced Glaucoma Intervention Study (AGIS): 5. Encapsulated bleb after initial trabeculectomy.

    Science.gov (United States)

    Schwartz, A L; Van Veldhuisen, P C; Gaasterland, D E; Ederer, F; Sullivan, E K; Cyrlin, M N

    1999-01-01

    To compare the incidence of encapsulated bleb after trabeculectomy in eyes with and without previous argon laser trabeculoplasty and to assess other risk factors for encapsulated bleb development. After medical treatment failure, eyes enrolled in the Advanced Glaucoma Intervention Study (AGIS) were randomly assigned to sequences of interventions starting with either argon laser trabeculoplasty or trabeculectomy. In the present study we compared the clinical course for 1 year after trabeculectomy in 119 eyes with failed argon laser trabeculoplasty with that of 379 eyes without previous argon laser trabeculoplasty. Data on bleb encapsulation were collected at the time that the encapsulation was diagnosed, and 3 and 6 months later. Of multiple factors examined in the AGIS data for the risk of developing encapsulated bleb, only male gender and high school graduation without further formal education were statistically significant. Encapsulation occurred in 18.5% of eyes with previous argon laser trabeculoplasty failure and 14.5% of eyes without previous argon laser trabeculoplasty (unadjusted relative risk, 1.27; 95% confidence limits = 0.81, 2.00; P = .23). After adjusting for age, gender, educational achievement, prescribed systemic beta-blockers, diabetes, visual field score, and years since glaucoma diagnosis, this difference remains statistically not significant. Four weeks after trabeculectomy, mean intraocular pressure was 7.5 mm Hg higher in eyes with (22.5 mm Hg) than without (15.0 mm Hg) encapsulated bleb; at 1 year after trabeculectomy and the resumption of medical therapy when needed, this excess was reduced to 1.4 mm Hg. This study, as did two previous studies, found male gender to be a risk factor for bleb encapsulation. Four studies, including the present study, have reported a higher rate of encapsulation in eyes with previous argon laser trabeculoplasty; in two of the studies, one of which was the present study, the rate was not statistically

  11. Thickness-Dependent Strain Effect on the Deformation of the Graphene-Encapsulated Au Nanoparticles

    Directory of Open Access Journals (Sweden)

    Shuangli Ye

    2014-01-01

    Full Text Available The strain effect on graphene-encapsulated Au nanoparticles is investigated. A finite-element calculation is performed to simulate the strain distribution and morphology of the monolayer and multilayer graphene-encapsulated Au nanoparticles, respectively. It can be found that the inhomogeneous strain and deformation are enhanced with the increasing shrinkage of the graphene shell. Moreover, the strain distribution and deformation are very sensitive to the layer number of the graphene shell. Especially, the inhomogeneous strain at the interface between the graphene shell and encapsulated Au nanoparticles is strongly tuned by the graphene thickness. For the mono- and bilayer graphene-encapsulated Au nanoparticles, the dramatic shape transformation can be observed. However, with increasing the graphene thickness further, there is hardly deformation for the encapsulated Au nanoparticles. These simulated results indicate that the strain and deformation can be designed by the graphene layer thickness, which provides an opportunity to engineer the structure and morphology of the graphene-encapsulated nanoparticles.

  12. Exploring encapsulation mechanism of DNA and mononucleotides in sol-gel derived silica.

    Science.gov (United States)

    Kapusuz, Derya; Durucan, Caner

    2017-07-01

    The encapsulation mechanism of DNA in sol-gel derived silica has been explored in order to elucidate the effect of DNA conformation on encapsulation and to identify the nature of chemical/physical interaction of DNA with silica during and after sol-gel transition. In this respect, double stranded DNA and dAMP (2'-deoxyadenosine 5'-monophosphate) were encapsulated in silica using an alkoxide-based sol-gel route. Biomolecule-encapsulating gels have been characterized using UV-Vis, 29 Si NMR, FTIR spectroscopy and gas adsorption (BET) to investigate chemical interactions of biomolecules with the porous silica network and to examine the extent of sol-gel reactions upon encapsulation. Ethidium bromide intercalation and leach out tests showed that helix conformation of DNA was preserved after encapsulation. For both biomolecules, high water-to-alkoxide ratio promoted water-producing condensation and prevented alcoholic denaturation. NMR and FTIR analyses confirmed high hydraulic reactivity (water adsorption) for more silanol groups-containing DNA and dAMP encapsulated gels than plain silica gel. No chemical binding/interaction occurred between biomolecules and silica network. DNA and dAMP encapsulated silica gelled faster than plain silica due to basic nature of DNA or dAMP containing buffer solutions. DNA was not released from silica gels to aqueous environment up to 9 days. The chemical association between DNA/dAMP and silica host was through phosphate groups and molecular water attached to silanols, acting as a barrier around biomolecules. The helix morphology was found not to be essential for such interaction. BET analyses showed that interconnected, inkbottle-shaped mesoporous silica network was condensed around DNA and dAMP molecules.

  13. The interpretation of encapsulating anaphors in Spanish and their functions

    DEFF Research Database (Denmark)

    Dam, Lotte

    2014-01-01

    Encapsulating anaphors differ from other types of anaphor by having one or more situations - not an entity - as its referent. The main aim of the article is to propose a hypothesis for how anaphoric encapsulation is resolved. The hypothesis builds on the cognitive linguistic theory of instruction...

  14. Microscale Strategies for Generating Cell-Encapsulating Hydrogels

    Directory of Open Access Journals (Sweden)

    Ali Khademhosseini

    2012-09-01

    Full Text Available Hydrogels in which cells are encapsulated are of great potential interest for tissue engineering applications. These gels provide a structure inside which cells can spread and proliferate. Such structures benefit from controlled microarchitectures that can affect the behavior of the enclosed cells. Microfabrication-based techniques are emerging as powerful approaches to generate such cell-encapsulating hydrogel structures. In this paper we introduce common hydrogels and their crosslinking methods and review the latest microscale approaches for generation of cell containing gel particles. We specifically focus on microfluidics-based methods and on techniques such as micromolding and electrospinning.

  15. Properties of Lactobacillus reuteri chitosan-calcium-alginate encapsulation under simulated gastrointestinal conditions.

    Science.gov (United States)

    Huang, Hui-Ying; Tang, Yi-Ju; King, V An-Erl; Chou, Jen-Wei; Tsen, Jen-Horng

    2015-03-01

    The protective effects of encapsulation on the survival of Lactobacillus reuteri and the retention of the bacterium's probiotic properties under simulated gastrointestinal conditions were investigated. Viable counts and the remaining probiotic properties of calcium (Ca)-alginate encapsulated (A group), chitosan-Ca-alginate encapsulated (CA group), and unencapsulated, free L. reuteri (F group) were determined. Encapsulation improved the survival of L. reuteri subjected to simulated gastrointestinal conditions, with the greatest protective effect achieved in the CA group. The degree of cell membrane injury increased with increasing bile salt concentrations at constant pH, but the extent of injury was less in the encapsulated than in the free cells. Adherence rates were, in descending order: CA (0.524%)>A (0.360%)>F (0.275%). Lactobacillus reuteri cells retained their antagonistic activity toward Listeria monocytogenes even after incubation of the lactobacilli under simulated gastrointestinal conditions. Displacement of the pathogen by cells released from either of the encapsulation matrices was higher than that by free cells. The safety of L. reuteri was demonstrated in an in vitro invasion assay. Copyright© by the Spanish Society for Microbiology and Institute for Catalan Studies.

  16. Environmentally Friendly Coating Technology for Autonomous Corrosion Control

    Science.gov (United States)

    Calle, Luz M.; Li, Wenyan; Buhrow, Jerry W.; Johnsey, Marissa N.; Jolley, Scott T.; Pearman, Benjamin P.; Zhang, Xuejun; Fitzpatrick, Lilliana; Gillis, Mathew; Blanton, Michael; hide

    2016-01-01

    This work concerns the development of environmentally friendly encapsulation technology, specifically designed to incorporate corrosion indicators, inhibitors, and self-healing agents into a coating, in such a way that the delivery of the indicators and inhibitors is triggered by the corrosion process, and the delivery of self-healing agents is triggered by mechanical damage to the coating. Encapsulation of the active corrosion control ingredients allows the incorporation of desired autonomous corrosion control functions such as: early corrosion detection, hidden corrosion detection, corrosion inhibition, and self-healing of mechanical damage into a coating. The technology offers the versatility needed to include one or several corrosion control functions into the same coating.The development of the encapsulation technology has progressed from the initial proof-of-concept work, in which a corrosion indicator was encapsulated into an oil-core (hydrophobic) microcapsule and shown to be delivered autonomously, under simulated corrosion conditions, to a sophisticated portfolio of micro carriers (organic, inorganic, and hybrid) that can be used to deliver a wide range of active corrosion ingredients at a rate that can be adjusted to offer immediate as well as long-term corrosion control. The micro carriers have been incorporated into different coating formulas to test and optimize the autonomous corrosion detection, inhibition, and self-healing functions of the coatings. This paper provides an overview of progress made to date and highlights recent technical developments, such as improved corrosion detection sensitivity, inhibitor test results in various types of coatings, and highly effective self-healing coatings based on green chemistry.

  17. Evaluation of the Antimicrobial and Antioxidant Activities of Origanum dictamnus Extracts before and after Encapsulation in Liposomes

    Directory of Open Access Journals (Sweden)

    John Tsaknis

    2007-05-01

    Full Text Available The antioxidant and antimicrobial activity of methanol or dichloromethane extracts of O. dictamnus, produced from wild and organic cultivated specimens, were determined. The Rancimat and malondialdehyde (MDA by HPLC methods were used to measure the antioxidant action, in comparison with that of the common commercial antioxidants butylated hydroxytoluene (BHT and α-tocopherol. The extracts that presented high antioxidant activity were encapsulated in liposomes and their antioxidant action was again estimated using differential scanning calorimetry (DSC. Thermaloxidative decomposition of the samples (pure liposomes and encapsulated extracts and the modification of the main transition temperature for the lipid mixture and the splitting of the calorimetric peak in the presence of the antioxidants were also studied by the DSC method. All extracts showed antioxidant and antimicrobial activities. Their action proved superior to α-tocopherol. The methanol extract of organic cultivated O. dictamnus (240 ppm showed higher activity than butylated hydroxytoluene. After encapsulation in liposomes the antioxidant as well as antimicrobial activities proved to be higher than those of the same extracts in pure form.

  18. Hanford waste encapsulation: strontium and cesium

    International Nuclear Information System (INIS)

    Jackson, R.R.

    1976-06-01

    The strontium and cesium fractions separated from high radiation level wastes at Hanford are converted to the solid strontium fluoride and cesium chloride salts, doubly encapsulated, and stored underwater in the Waste Encapsulation and Storage Facility (WESF). A capsule contains approximately 70,000 Ci of 137 Cs or 70,000 to 140,000 Ci of 90 Sr. Materials for fabrication of process equipment and capsules must withstand a combination of corrosive chemicals, high radiation dosages and frequently, elevated temperatures. The two metals selected for capsules, Hastelloy C-276 for strontium fluoride and 316-L stainless steel for cesium chloride, are adequate for prolonged containment. Additional materials studies are being done both for licensing strontium fluoride as source material and for second generation process equipment

  19. Poly(lactide-co-glycolide) encapsulated hydroxyapatite microspheres for sustained release of doxycycline

    International Nuclear Information System (INIS)

    Wang Xiaoyun; Xu Hui; Zhao Yanqiu; Wang Shaoning; Abe, Hiroya; Naito, Makio; Liu Yanli; Wang Guoqing

    2012-01-01

    Highlights: ► PLGA encapsulated HAP-MSs were used for the sustained delivery of Doxycycline (Doxy, a broad spectrum tetracycline antibiotic). ► Sustained Doxy release without obvious burst was observed. ► Mechanism of the sustained Doxy release was illustrated. ► Sustained Doxy release character in vivo was also obtained, the plasma Doxy levels were relatively lower and steady compared to that of the un-encapsulated HAP-MSs. - Abstract: The purpose of this study was to prepare a poly(lactide-co-glycolide) (PLGA) encapsulated hydroxyapatite microspheres (HAP-MSs) as injectable depot for sustained delivery of Doxycycline (Doxy). Doxy loaded HAP-MSs (Doxy-HAP-MSs) were encapsulated with PLGA by solid-in-oil-in-water (S/O/W) emulsion-solvent evaporation technique, the effects of the PLGA used (various intrinsic viscosity and LA/GA ratio) and ratio of PLGA/HAP-MSs on the formation of Doxy-HAP-MSs and in vitro release of Doxy were studied. The results showed that sustained drug release without obvious burst was obtained by using PLGA encapsulated HAP-MSs as the carrier, also the drug release rate could be tailored by changing the ratio of PLGA/HAP-MSs, or PLGA of various intrinsic viscosities or LA/GA ratio. Lower ratio of PLGA/HAP-MSs corresponded faster Doxy release, e.g. for the microspheres of PLGA/HAP-MSs ratio of 8 and 0.25, the in vitro Doxy release percents at the end of 7days were about 23% and 76%, respectively. Higher hydrophilicity (higher ratio of GA to LA) and lower molecular weight of PLGA corresponded to higher Doxy release rates. For in vivo release study, PLGA encapsulated HAP-MSs were subcutaneously injected to the back of mice, and the results showed good correlation between the in vivo and in vitro drug release. Meanwhile, the plasma Doxy levels after subcutaneous administration of PLGA encapsulated Doxy-HAP-MSs were relatively lower and steady compared to that of the un-encapsulated microspheres. In conclusion, PLGA encapsulated HAP-MSs may

  20. Waste management technology development and demonstration programs at Brookhaven National Laboratory

    Science.gov (United States)

    Kalb, Paul D.; Colombo, Peter

    1991-01-01

    Two thermoplastic processes for improved treatment of radioactive, hazardous, and mixed wastes were developed from bench scale through technology demonstration: polyethylene encapsulation and modified sulfur cement encapsulation. The steps required to bring technologies from the research and development stage through full scale implementation are described. Both systems result in durable waste forms that meet current Nuclear Regulatory Commission and Environmental Protection Agency regulatory criteria and provide significant improvements over conventional solidification systems such as hydraulic cement. For example, the polyethylene process can encapsulate up to 70 wt pct. nitrate salt, compared with a maximum of about 20 wt pct. for the best hydraulic cement formulation. Modified sulfur cement waste forms containing as much as 43 wt pct. incinerator fly ash were formulated, whereas the maximum quantity of this waste in hydraulic cement is 16 wt pct.

  1. Optimization of NMR spectroscopy of encapsulated proteins dissolved in low viscosity fluids

    International Nuclear Information System (INIS)

    Nucci, Nathaniel V.; Marques, Bryan S.; Bédard, Sabrina; Dogan, Jakob; Gledhill, John M.; Moorman, Veronica R.; Peterson, Ronald W.; Valentine, Kathleen G.; Wand, Alison L.; Wand, A. Joshua

    2011-01-01

    Comprehensive application of solution NMR spectroscopy to studies of macromolecules remains fundamentally limited by the molecular rotational correlation time. For proteins, molecules larger than 30 kDa require complex experimental methods, such as TROSY in conjunction with isotopic labeling schemes that are often expensive and generally reduce the potential information available. We have developed the reverse micelle encapsulation strategy as an alternative approach. Encapsulation of proteins within the protective nano-scale water pool of a reverse micelle dissolved in ultra-low viscosity nonpolar solvents overcomes the slow tumbling problem presented by large proteins. Here, we characterize the contributions from the various components of the protein-containing reverse micelle system to the rotational correlation time of the encapsulated protein. Importantly, we demonstrate that the protein encapsulated in the reverse micelle maintains a hydration shell comparable in size to that seen in bulk solution. Using moderate pressures, encapsulation in ultra-low viscosity propane or ethane can be used to magnify this advantage. We show that encapsulation in liquid ethane can be used to reduce the tumbling time of the 43 kDa maltose binding protein from ∼23 to ∼10 ns. These conditions enable, for example, acquisition of TOCSY-type data resolved on the adjacent amide NH for the 43 kDa encapsulated maltose binding protein dissolved in liquid ethane, which is typically impossible for proteins of such size without use of extensive deuteration or the TROSY effect.

  2. Advances in spot curing technology

    International Nuclear Information System (INIS)

    Burga, R.

    1999-01-01

    A brief review of spot curing technology was presented. The process which a spot of energy of a specific wavelength bandwidth and irradiance is used to cause a coating, encapsulant or adhesive to change from a liquid to a solid state

  3. Quantitative generalized ratiometric fluorescence spectroscopy for turbid media based on probe encapsulated by biologically localized embedding

    International Nuclear Information System (INIS)

    Yan, Xiu-Fang; Chen, Zeng-Ping; Cui, Yin-Yin; Hu, Yuan-Liang; Yu, Ru-Qin

    2016-01-01

    PEBBLE (probe encapsulated by biologically localized embedding) nanosensor encapsulating an intensity-based fluorescence indicator and an inert reference fluorescence dye inside the pores of stable matrix can be used as a generalized wavelength-ratiometric probe. However, the lack of an efficient quantitative model render the choices of inert reference dyes and intensity-based fluorescence indicators used in PEBBLEs based generalized wavelength-ratiometric probes rather limited. In this contribution, an extended quantitative fluorescence model was derived specifically for generalized wavelength-ratiometric probes based on PEBBLE technique (QFM GRP ) with a view to simplify the design of PEBBLEs and hence further extend their application potentials. The effectiveness of QFM GRP has been tested on the quantitative determination of free Ca 2+ in both simulated and real turbid media using a Ca 2+ sensitive PEBBLE nanosensor encapsulating Rhod-2 and eosin B inside the micropores of stable polyacrylamide matrix. Experimental results demonstrated that QFM GRP could realize precise and accurate quantification of free Ca 2+ in turbid samples, even though there is serious overlapping between the fluorescence excitation peaks of eosin B and Ca 2+ bound Rhod-2. The average relative predictive error value of QFM GRP for the test simulated turbid samples was 5.9%, about 2–4 times lower than the corresponding values of partial least squares calibration model and the empirical ratiometric model based on the ratio of fluorescence intensities at the excitation peaks of Ca 2+ bound Rhod-2 and eosin B. The recovery rates of QFM GRP for the real and spiked turbid samples varied from 93.1% to 101%, comparable to the corresponding results of atomic absorption spectrometry. - Highlights: • An advanced model was derived for generalized wavelength-ratiometric PEBBLEs. • The model can simplify the design of generalized wavelength-ratiometric PEBBLEs. • The model realized accurate

  4. Atomically Precise Nanocluster Assemblies Encapsulating Plasmonic Gold Nanorods.

    Science.gov (United States)

    Chakraborty, Amrita; Fernandez, Ann Candice; Som, Anirban; Mondal, Biswajit; Natarajan, Ganapati; Paramasivam, Ganesan; Lahtinen, Tanja; Häkkinen, Hannu; Nonappa, Nonappa; Pradeep, Thalappil

    2018-04-01

    We present the self-assembled structures of atomically precise, ligand-protected noble metal nanoclusters leading to encapsulation of plasmonic gold nanorods (GNRs). Unlike highly sophisticated DNA nanotechnology, our approach demonstrates a strategically simple hydrogen bonding-directed self-assembly of nanoclusters leading to octahedral nanocrystals encapsulating GNRs. Specifically, we use the p-mercaptobenzoic acid (pMBA) protected atomically precise nanocluster, Na4[Ag44(pMBA)30] and pMBA functionalized GNRs. High resolution transmission and scanning transmission electron tomographic reconstructions suggest that the geometry of the GNR surface is responsible for directing the assembly of silver nanoclusters via H-bonding leading to octahedral symmetry. Further, use of water dispersible gold nanoclusters, Au~250(pMBA)n and Au102(pMBA)44 also formed layered shells encapsulating GNRs. Such cluster assemblies on colloidal particles present a new category of precision hybrids with diverse possibilities. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Polyphosphonate induced coacervation of chitosan: Encapsulation of proteins/enzymes and their biosensing

    International Nuclear Information System (INIS)

    Liu, Hailing; Cui, Yanyun; Li, Pan; Zhou, Yiming; Chen, Yu; Tang, Yawen; Lu, Tianhong

    2013-01-01

    Graphical abstract: Based on the coacervation of chitosan via the ionotropic crosslinking interaction, proteins/enzymes can be encapsulated in situ into chitosan matrix. -- Highlights: •The ionotropic crosslinking interactions result in the coacervation of chitosan. •A phosphonate-assisted encapsulation of proteins in chitosan matrix is introduced. •The encapsulated proteins retain their bioactivity. •The encapsulation method can be used to fabricate various chitosan-based biosensors. -- Abstract: Based on the polyphosphonate-assisted coacervation of chitosan, a simple and versatile procedure for the encapsulation of proteins/enzymes in chitosan–carbon nanotubes (CNTs) composites matrix was developed. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectrum (EDS) mapping demonstrated the hemoglobin (Hb) uniformly distributed into chitosan–CNTs composites matrix. Raman measurements indicated the CNTs in composites matrix retained the electronic and structural integrities of the pristine CNTs. Fourier transform infrared (FT-IR), ultraviolet–visible (UV–vis) and circular dichroism (CD) spectroscopy displayed the encapsulated Hb preserved their near-native structure, indicating the polyphosphonate–chitosan–CNTs composites possessed excellent biocompatibility for the encapsulation of proteins/enzymes. Electrochemical measurements indicated the encapsulated Hb could directly exchange electron with the substrate electrode. Moreover, the modified electrode showed excellent bioelectrocatalytic activity for the reduction of hydrogen peroxide. Under optimum experimental conditions, the fabricated electrochemical sensor displayed the fast response (less than 3 s), wide linear range (7.0 × 10 −7 to 2.0 × 10 −3 M) and low detection limit (4.0 × 10 −7 M) for the determination of hydrogen peroxide. This newly developed protocol was simple and mild and would certainly

  6. Polyphosphonate induced coacervation of chitosan: Encapsulation of proteins/enzymes and their biosensing

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Hailing; Cui, Yanyun; Li, Pan; Zhou, Yiming; Chen, Yu, E-mail: ndchenyu@yahoo.cn; Tang, Yawen; Lu, Tianhong

    2013-05-07

    Graphical abstract: Based on the coacervation of chitosan via the ionotropic crosslinking interaction, proteins/enzymes can be encapsulated in situ into chitosan matrix. -- Highlights: •The ionotropic crosslinking interactions result in the coacervation of chitosan. •A phosphonate-assisted encapsulation of proteins in chitosan matrix is introduced. •The encapsulated proteins retain their bioactivity. •The encapsulation method can be used to fabricate various chitosan-based biosensors. -- Abstract: Based on the polyphosphonate-assisted coacervation of chitosan, a simple and versatile procedure for the encapsulation of proteins/enzymes in chitosan–carbon nanotubes (CNTs) composites matrix was developed. Scanning electron microscopy (SEM), transmission electron microscopy (TEM), X-ray photoelectron spectroscopy (XPS), energy dispersive spectrum (EDS) mapping demonstrated the hemoglobin (Hb) uniformly distributed into chitosan–CNTs composites matrix. Raman measurements indicated the CNTs in composites matrix retained the electronic and structural integrities of the pristine CNTs. Fourier transform infrared (FT-IR), ultraviolet–visible (UV–vis) and circular dichroism (CD) spectroscopy displayed the encapsulated Hb preserved their near-native structure, indicating the polyphosphonate–chitosan–CNTs composites possessed excellent biocompatibility for the encapsulation of proteins/enzymes. Electrochemical measurements indicated the encapsulated Hb could directly exchange electron with the substrate electrode. Moreover, the modified electrode showed excellent bioelectrocatalytic activity for the reduction of hydrogen peroxide. Under optimum experimental conditions, the fabricated electrochemical sensor displayed the fast response (less than 3 s), wide linear range (7.0 × 10{sup −7} to 2.0 × 10{sup −3} M) and low detection limit (4.0 × 10{sup −7} M) for the determination of hydrogen peroxide. This newly developed protocol was simple and mild and

  7. High temperature in-situ observations of multi-segmented metal nanowires encapsulated within carbon nanotubes by in-situ filling technique.

    Science.gov (United States)

    Hayashi, Yasuhiko; Tokunaga, Tomoharu; Iijima, Toru; Iwata, Takuya; Kalita, Golap; Tanemura, Masaki; Sasaki, Katsuhiro; Kuroda, Kotaro

    2012-08-08

    Multi-segmented one-dimensional metal nanowires were encapsulated within carbon nanotubes (CNTs) through in-situ filling technique during plasma-enhanced chemical vapor deposition process. Transmission electron microscopy (TEM) and environmental TEM were employed to characterize the as-prepared sample at room temperature and high temperature. The selected area electron diffractions revealed that the Pd4Si nanowire and face-centered-cubic Co nanowire on top of the Pd nanowire were encapsulated within the bottom and tip parts of the multiwall CNT, respectively. Although the strain-induced deformation of graphite walls was observed, the solid-state phases of Pd4Si and Co-Pd remain even at above their expected melting temperatures and up to 1,550 ± 50°C. Finally, the encapsulated metals were melted and flowed out from the tip of the CNT after 2 h at the same temperature due to the increase of internal pressure of the CNT.

  8. Unique coexistence of dispersion stability and nanoparticle chemisorption in alkylamine/alkylacid encapsulated silver nanocolloids.

    Science.gov (United States)

    Aoshima, Keisuke; Hirakawa, Yuya; Togashi, Takanari; Kurihara, Masato; Arai, Shunto; Hasegawa, Tatsuo

    2018-04-17

    Surface encapsulation of metal nanoparticles (NPs) is fundamental to achieve sufficient dispersion stability of metal nanocolloids, or metal nanoink. However, the feature is incompatible with surface reactive nature of the metal NPs, although these features are both essential to realizing the functional applications into printed electronics technologies. Here we show that two different kinds of encapsulation for silver NPs (AgNPs) by alkylamine and alkylacid together are the key to achieve unique compatibility between the high dispersion stability as dense nanoclolloids and the AgNP chemisorption printing on activated patterned polymer surfaces. Advanced confocal dynamic light scattering study reveals that an additive trace amount of oleic acid is the critical parameter for controlling the dispersion and coagulative (or surface-reactive) characteristics of the silver nanocolloids. The composition of the disperse media is also important for obtaining highly concentrated but low-viscosity silver nanocolloids that show very stable dispersion. The results demonstrate that the high-resolution AgNP chemisorption printing is possible only by using unique silver nanocolloids composed of an exceptional balance of ligand formulation and dispersant composition.

  9. A Review of New and Developing Technology to Significantly Improve Mars Sample-Return Missions

    Science.gov (United States)

    Carsey, F.; Brophy, J.; Gilmore, M.; Rodgers, D.; Wilcox, B.

    2000-07-01

    A JPL development activity was initiated in FY 1999 for the purpose of examining and evaluating technologies that could materially improve future (i.e., beyond the 2005 launch) Mars sample return missions. The scope of the technology review was comprehensive and end-to-end; the goal was to improve mass, cost, risk, and scientific return. A specific objective was to assess approaches to sample return with only one Earth launch. While the objective of the study was specifically for sample-return, in-situ missions can also benefit from using many of the technologies examined.

  10. Structure and electronic properties of molybdenum monatomic wires encapsulated in carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    GarcIa-Fuente, A; Vega, A [Departamento de Fisica Teorica, Atomica y Optica. Universidad de Valladolid, E-47011 Valladolid (Spain); GarcIa-Suarez, V M; Ferrer, J [Departamento de Fisica and CINN, Universidad de Oviedo, 33007 Oviedo (Spain)

    2011-07-06

    Monatomic chains of molybdenum encapsulated in single-walled carbon nanotubes (CNTs) of different chiralities are investigated using density functional theory. We determine the optimal size of the CNT for encapsulating a single atomic wire, as well as the most stable atomic arrangement adopted by the wire. We also study the transport properties in the ballistic regime by computing the transmission coefficients and tracing them back to the electronic conduction channels of the wire and the host. We predict that CNTs of appropriate radii encapsulating a Mo wire have metallic behavior, even if both the nanotube and the wire are insulators. Therefore, encapsulation of Mo wires in CNTs is a way to create conductive quasi-one-dimensional hybrid nanostructures.

  11. Encapsulated Curcumin for Transdermal Administration

    African Journals Online (AJOL)

    Purpose: To develop a proniosomal carrier system of curcumin for transdermal delivery. Methods: Proniosomes of curcumin were prepared by encapsulation of the drug in a mixture of Span 80, cholesterol and diethyl ether by ether injection method, and then investigated as a transdermal drug delivery system (TDDS).

  12. Reactants encapsulation and Maillard Reaction

    NARCIS (Netherlands)

    Troise, A.D.; Fogliano, V.

    2013-01-01

    In the last decades many efforts have been addressed to the control of Maillard Reaction products in different foods with the aim to promote the formation of compounds having the desired color and flavor and to reduce the concentration of several potential toxic molecules. Encapsulation, already

  13. Improved performance of InSe field-effect transistors by channel encapsulation

    Science.gov (United States)

    Liang, Guangda; Wang, Yiming; Han, Lin; Yang, Zai-Xing; Xin, Qian; Kudrynskyi, Zakhar R.; Kovalyuk, Zakhar D.; Patanè, Amalia; Song, Aimin

    2018-06-01

    Due to the high electron mobility and photo-responsivity, InSe is considered as an excellent candidate for next generation electronics and optoelectronics. In particular, in contrast to many high-mobility two-dimensional (2D) materials, such as phosphorene, InSe is more resilient to oxidation in air. Nevertheless, its implementation in future applications requires encapsulation techniques to prevent the adsorption of gas molecules on its surface. In this work, we use a common lithography resist, poly(methyl methacrylate) (PMMA) to encapsulate InSe-based field-effect transistors (FETs). The encapsulation of InSe by PMMA improves the electrical stability of the FETs under a gate bias stress, and increases both the drain current and electron mobility. These findings indicate the effectiveness of the PMMA encapsulation method, which could be applied to other 2D materials.

  14. Dosimetric study of a new polymer encapsulated palladium-103 seed

    International Nuclear Information System (INIS)

    Bernard, S; Vynckier, S

    2005-01-01

    The use of low-energy photon emitters for brachytherapy applications, as in the treatment of prostate or ocular tumours, has increased significantly over the last few years. Several new seed models utilizing 103 Pd and 125 I have recently been introduced. Following the TG43U1 recommendations of the AAPM (American Association of Physicists in Medicine) (Rivard et al 2004 Med. Phys. 31 633), dose distributions around these low-energy photon emitters are characterized by the dose rate constant, the radial dose function and the anisotropy function in water. These functions and constants can be measured for each new seed in a solid phantom (i.e. solid water such as WT1) using high spatial resolution detectors such as very small thermoluminescent detectors. These experimental results in solid water must then be converted into liquid water by using Monte Carlo simulations. This paper presents the dosimetric parameters of a new palladium seed, OptiSeed TM (produced by International Brachytherapy (IBt), Seneffe, Belgium), made with a biocompatible polymeric shell and with a design that differs from the hollow titanium encapsulated seed, InterSource 103 , produced by the same company. A polymer encapsulation was chosen by the company IBt in order to reduce the quantity of radioactive material needed for a given dose rate, and to improve the symmetry of the radiation field around the seed. The necessary experimental data were obtained by measurements with LiF thermoluminescent dosimeters (1 mm 3 ) in a solid water phantom (WT1) and then converted to values in liquid water using Monte Carlo calculations (MCNP-4C). Comparison of the results with a previous study by Reniers et al (2002 Appl. Radiat. Isot. 57 805) shows very good agreement for the dose rate constant and for the radial dose function. In addition, the results also indicate an improvement in isotropy compared to a conventional titanium encapsulated seed. The relative dose (anisotropy value relative to 90 deg.) from

  15. Synthesis of potassium cobalt hexacyanoferrate encapsulated polymeric beads for extraction of Cs from acidic solution

    International Nuclear Information System (INIS)

    Kanagare, Anant B.; Singh, Krishan Kant; Kumar, Manmohan; Shinde, Vaishali S.

    2016-01-01

    137 Cs is one of the major radionuclides formed during the fission of 235 U in nuclear reactors. It is a main source of radiation in High Level Liquid Waste (HLLW) generated after the reprocessing of spent nuclear fuel. Separation of Cs from HLLW, decreases radiation exposure throughout the vitrification process and avoids thermal deformation of conditioned waste matrix during storage. Therefore, there is a necessity for selective separation of Cs from HLLW and other such acidic waste streams. The liquid-liquid extraction is widely used as a technology for separation and recovery of metal ions from radioactive wastes. Such technologies play an important role in all the bulk separation processes, but they have noticeable limitations, such as difficulty in handling, losses of extractant in aqueous phase, secondary waste generation, third phase problems at higher metal loading, etc. Due to these limitations it is necessary to explore the advance, more capable and exactly feasible alternatives. In this respect it is assumed that solid-liquid based Extractant Encapsulated Polymeric Beads (EEPBs) may resolve some of these limitations. The metal hexacyanoferrates (HCFs) are preferred as Cs extractant over the other materials due to their selectivity and high capacity to remove cesium from aqueous radioactive wastes. Here we report the synthesis and characterization of a novel potasium cobalt hexacyanoferrate (KCoHCF) encapsulated polyether sulphone beads, and its use as a cesium sorbent material

  16. Swedish encapsulation station review

    Energy Technology Data Exchange (ETDEWEB)

    Andersson, Sven Olof; Brunzell, P.; Heibel, R.; McCarthy, J.; Pennington, C.; Rusch, C.; Varley, G. [NAC International, Zuerich (Switzerland)

    1998-06-01

    In the Encapsulation Station (ES) Review performed by NAC International, a number of different areas have been studied. The main objectives with the review have been to: Perform an independent review of the cost estimates for the ES presented in SKB`s document `Plan 1996`. This has been made through comparisons between the ES and BNFL`s Waste Encapsulation Plant (WEP) at Sellafield as well as with the CLAB facility. Review the location of the ES (at the CLAB site or at the final repository) and its interaction with other parts of the Swedish system for spent fuel management. Review the logistics and plant capacity of the ES. Identify important safety aspects of the ES as a basis for future licensing activities. Based on NAC International`s experience of casks for transport and storage of spent fuel, review the basic design of the copper/steel canister and the transport cask. This review insides design, manufacturing, handling and licensing aspects. Perform an overall comparison between the ES project and the CLAB project with the objective to identify major project risks and discuss their mitigation 19 refs, 9 figs, 35 tabs

  17. Effects of SiO2 encapsulation and laser processing on single CdTe/ZnTe quantum dots grown on Si (001) substrates

    International Nuclear Information System (INIS)

    Lee, Hong Seok; Rastelli, Armando; Schmidt, Oliver G.; Kim, Tae Whan; Lee, In Won

    2011-01-01

    Micro-photoluminescence (μ-PL) measurements are carried out to investigate the effects of SiO 2 encapsulation and laser processing of single CdTe/ZnTe quantum dots (QDs) grown on Si (001) substrates by using molecular beam epitaxy and atomic layer epitaxy. After laser processing, the μ-PL peak shift for the 200-nm SiO 2 capped single QD is larger than that of the as-grown sample. The large μ-PL peak shift in the 200-nm SiO 2 capped sample is related to the compressive stress induced by the ZnTe cap layer during laser processing. These results indicate that SiO 2 encapsulation and laser processing represent effective methods for achieving local wavelength tuning in single QDs.

  18. Controlled ice nucleation using freeze-dried Pseudomonas syringae encapsulated in alginate beads.

    Science.gov (United States)

    Weng, Lindong; Tessier, Shannon N; Swei, Anisa; Stott, Shannon L; Toner, Mehmet

    2017-04-01

    The control of ice nucleation is of fundamental significance in many process technologies related to food and pharmaceutical science and cryobiology. Mechanical perturbation, electromagnetic fields and ice-nucleating agents (INAs) have been known to induce ice nucleation in a controlled manner. But these ice-nucleating methods may suffer from cumbersome manual operations, safety concerns of external fields, and biocompatibility and recovery issues of INA particles, especially when used in living systems. Given the automatic ice-seeding nature of INAs, a promising solution to overcome some of the above limitations is to engineer a biocomposite that accommodates the INA particles but minimizes their interactions with biologics, as well as enabling the recovery of used particles. In this study, freeze-dried Pseudomonas syringae, a model ice-nucleating agent, was encapsulated into microliter-sized alginate beads. We evaluated the performance of the bacterial hydrogel beads to initiate ice nucleation in water and aqueous glycerol solution by investigating factors including the size and number of the beads and the local concentration of INA particles. In the aqueous sample of a fixed volume, the total mass of the INA particles (m) was found to be the governing parameter that is solely responsible for determining the ice nucleation performance of the bacterial hydrogel beads. The freezing temperature has a strong positive linear correlation with log 10 m. The findings in this study provide an effective, predictable approach to control ice nucleation, which can improve the outcome and standardization of many ice-assisted process technologies. Copyright © 2017 Elsevier Inc. All rights reserved.

  19. Graphene-bonded and -encapsulated si nanoparticles for lithium ion battery anodes.

    Science.gov (United States)

    Wen, Yang; Zhu, Yujie; Langrock, Alex; Manivannan, Ayyakkannu; Ehrman, Sheryl H; Wang, Chunsheng

    2013-08-26

    Silicon (Si) has been considered a very promising anode material for lithium ion batteries due to its high theoretical capacity. However, high-capacity Si nanoparticles usually suffer from low electronic conductivity, large volume change, and severe aggregation problems during lithiation and delithiation. In this paper, a unique nanostructured anode with Si nanoparticles bonded and wrapped by graphene is synthesized by a one-step aerosol spraying of surface-modified Si nanoparticles and graphene oxide suspension. The functional groups on the surface of Si nanoparticles (50-100 nm) not only react with graphene oxide and bind Si nanoparticles to the graphene oxide shell, but also prevent Si nanoparticles from aggregation, thus contributing to a uniform Si suspension. A homogeneous graphene-encapsulated Si nanoparticle morphology forms during the aerosol spraying process. The open-ended graphene shell with defects allows fast electrochemical lithiation/delithiation, and the void space inside the graphene shell accompanied by its strong mechanical strength can effectively accommodate the volume expansion of Si upon lithiation. The graphene shell provides good electronic conductivity for Si nanoparticles and prevents them from aggregating during charge/discharge cycles. The functionalized Si encapsulated by graphene sample exhibits a capacity of 2250 mAh g⁻¹ (based on the total mass of graphene and Si) at 0.1C and 1000 mAh g⁻¹ at 10C, and retains 85% of its initial capacity even after 120 charge/discharge cycles. The exceptional performance of graphene-encapsulated Si anodes combined with the scalable and one-step aerosol synthesis technique makes this material very promising for lithium ion batteries. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  20. Preparation of higher-actinide burnup and cross section samples

    International Nuclear Information System (INIS)

    Adair, H.L.; Kobisk, E.H.; Quinby, T.C.; Thomas, D.K.; Dailey, J.M.

    1981-01-01

    A joint research program involving the United States and the United Kingdom was instigated about four years ago for the purpose of studying burnup of higher actinides using in-core irradiation in the fast reactor at Dounreay, Scotland. Simultaneously, determination of cross sections of a wide variety of higher actinide isotopes was proposed. Coincidental neutron flux and energy spectral measurements were to be made using vanadium encapsulated dosimetry materials in the immediate region of the burnup and cross section samples. The higher actinide samples chosen for the burnup study were 241 Am and 244 Cm in the forms of Am 2 O 3 , Cm 2 O 3 , and Am 6 Cm(RE) 7 O 21 , where (RE) represents a mixture of lanthanide sesquioxides. It is the purpose of this paper to describe technology development and its application in the preparation of the fuel specimens and the cross section specimens that are being used in this cooperative program

  1. Zein-based colloidal particles for encapsulation and delivery of epigallocatechin gallate

    NARCIS (Netherlands)

    Donsì, F.; Voudouris, P.; Veen, S.J.; Velikov, K.P.

    Zein, a water insoluble plant protein from a renewable natural source, has been identified as a highly promising material for the production of protein-based colloidal particles for the encapsulation of lipophilic compounds. However, the encapsulation of hydrophilic, water-soluble, bioactive

  2. Survival of encapsulated Lactobacillus plantarum during isothermal heating and bread baking

    NARCIS (Netherlands)

    Zhang, L.; Chen, Xiao Dong; Boom, R.M.; Schutyser, M.A.I.

    2018-01-01

    The effect of encapsulation on the survival of Lactobacillus plantarum during isothermal heating and bread baking was investigated. Four encapsulating materials were evaluated, i.e., reconstituted skim milk (RSM), gum arabic (GA), maltodextrin (MD) and inulin. Freeze dried bacteria survived better

  3. Encapsulation of high temperature thermoelectric modules

    Energy Technology Data Exchange (ETDEWEB)

    Salvador, James R.; Sakamoto, Jeffrey; Park, Youngsam

    2017-07-11

    A method of encapsulating a thermoelectric device and its associated thermoelectric elements in an inert atmosphere and a thermoelectric device fabricated by such method are described. These thermoelectric devices may be intended for use under conditions which would otherwise promote oxidation of the thermoelectric elements. The capsule is formed by securing a suitably-sized thin-walled strip of oxidation-resistant metal to the ceramic substrates which support the thermoelectric elements. The thin-walled metal strip is positioned to enclose the edges of the thermoelectric device and is secured to the substrates using gap-filling materials. The strip, substrates and gap-filling materials cooperatively encapsulate the thermoelectric elements and exclude oxygen and water vapor from atmospheric air so that the elements may be maintained in an inert, non-oxidizing environment.

  4. Patterned three-dimensional encapsulation of embryonic stem cells using dielectrophoresis and stereolithography.

    Science.gov (United States)

    Bajaj, Piyush; Marchwiany, Daniel; Duarte, Carlos; Bashir, Rashid

    2013-03-01

    Controlling the assembly of cells in three dimensions is very important for engineering functional tissues, drug screening, probing cell-cell/cell-matrix interactions, and studying the emergent behavior of cellular systems. Although the current methods of cell encapsulation in hydrogels can distribute them in three dimensions, these methods typically lack spatial control of multi-cellular organization and do not allow for the possibility of cell-cell contacts as seen for the native tissue. Here, we report the integration of dielectrophoresis (DEP) with stereolithography (SL) apparatus for the spatial patterning of cells on custom made gold micro-electrodes. Afterwards, they are encapsulated in poly (ethylene glycol) diacrylate (PEGDA) hydrogels of different stiffnesses. This technique can mimic the in vivo microscale tissue architecture, where the cells have a high degree of three dimensional (3D) spatial control. As a proof of concept, we show the patterning and encapsulation of mouse embryonic stem cells (mESCs) and C2C12 skeletal muscle myoblasts. mESCs show high viability in both the DEP (91.79% ± 1.4%) and the no DEP (94.27% ± 0.5%) hydrogel samples. Furthermore, we also show the patterning of mouse embryoid bodies (mEBs) and C2C12 spheroids in the hydrogels, and verify their viability. This robust and flexible in vitro platform can enable various applications in stem cell differentiation and tissue engineering by mimicking elements of the native 3D in vivo cellular micro-environment. Copyright © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. Key technology for (V)HTR: laser beam joining of SiC

    International Nuclear Information System (INIS)

    Knorr, J.; Lippmann, W.; Reinecke, A.M.; Wolf, R.; Rasper, R.; Kerber, A.; Wolter, A.

    2005-01-01

    Laser beam joining has numerous advantages over other methods presently known. After having been developed successful for brazing silicon carbide for high temperature applications, this technology is now also available for silicon nitride. Thus the field of application of SiC and Si 3 N 4 which are very interesting materials for the nuclear sector is considerably extended thanks to this new technology. Ceramic encapsulation of fuel and absorber increases the margins for operation at very high temperatures. Additionally, without ceramic encapsulation of the main core components, it will be difficult to continue claiming non-catastrophic behaviour for the (V)HTR. (orig.)

  6. Utilization of Microcapsule Technology in Foods.

    Science.gov (United States)

    Zhang, Chuanxiang; Li, Xiaolong; Liu, You-Nian; Zhang, Fengqin

    2015-12-01

    Microencapsulation technology has greatly accelerated the development of food industry and has a bright future for further applications. In this review paper, we introduce the current researches, latest advances and trends of core materials, wall materials, microencapsulation technology, as well as the encapsulation of food additives, bioactive substance, esculent oils, probiotics and other substances, and their application in food industry.

  7. Alginate: A Versatile Biomaterial to Encapsulate Isolated Ovarian Follicles.

    Science.gov (United States)

    Vanacker, Julie; Amorim, Christiani A

    2017-07-01

    In vitro culture of ovarian follicles isolated or enclosed in ovarian tissue fragments and grafting of isolated ovarian follicles represent a potential alternative to restore fertility in cancer patients who cannot undergo cryopreservation of embryos or oocytes or transplantation of frozen-thawed ovarian tissue. In this regard, respecting the three-dimensional (3D) architecture of isolated follicles is crucial to maintaining their proper follicular physiology. To this end, alginate hydrogel has been widely investigated using follicles from numerous animal species, yielding promising results. The goal of this review is therefore to provide an overview of alginate applications utilizing the biomaterial as a scaffold for 3D encapsulation of isolated ovarian follicles. Different methods of isolated follicle encapsulation in alginate are discussed in this review, as its use of 3D alginate culture systems as a tool for in vitro follicle analysis. Possible improvements of this matrix, namely modification with arginine-glycine-aspartic acid peptide or combination with fibrin, are also summarized. Encouraging results have been obtained in different animal models, and particularly with isolated follicles encapsulated in alginate matrices and grafted to mice. This summary is designed to guide the reader towards development of next-generation alginate scaffolds, with enhanced properties for follicle encapsulation.

  8. UV-screening chitosan nanocontainers: increasing the photostability of encapsulated materials and controlled release

    International Nuclear Information System (INIS)

    Anumansirikul, Nattaporm; Wittayasuporn, Mayura; Klinubol, Patcharawalai; Tachaprutinun, A; Wanichwecharungruang, Supason P

    2008-01-01

    Methyl ether terminated poly(ethylene glycol)-4-methoxycinnamoylphthaloylchitosan (PCPLC), a UV absorptive polymer, and methyl ether terminated poly(ethylene glycol)-phthaloylchitosan (PPLC) were synthesized, characterized and self-assembled into stable water-dispersible spherical nanoparticles. The encapsulation of a model compound, 2-ethylhexyl-4-methoxycinnamate (EHMC), was carried out to give particles with 67% (w/w) EHMC loading. The E to Z photoisomerization of EHMC encapsulated inside both particles was monitored and compared to non-encapsulated EHMC. Minimal E to Z photoisomerization was observed when EHMC was encapsulated in PCPLC particles prepared from a polymer with a maximum degree of 4-methoxycinnamoyl substitution. The results indicated that the grafted UVB absorptive chromophore, 4-methoxycinnamoyl moieties, situated at the shell of PCPLC nanoparticles acted as a UV-filtering barrier, protecting the encapsulated EHMC from the UVB radiation, thus minimizing its photoisomerization. In vitro experiments revealed the pH-dependent controlled release of EHMC from PCPLC and PPLC particles. Ex vivo experiments, using a Franz diffusion cell with baby mouse skin, indicated that neither PPLC nor PCPLC particles could penetrate the skin into the receptor medium after a 24 h topical application. When applied on the baby mouse skin, both EHMC-encapsulated PPLC and EHMC-encapsulated PCPLC showed comparable controlled releases of the EHMC. The released EHMC could transdermally penetrate the baby mouse skin

  9. UV-screening chitosan nanocontainers: increasing the photostability of encapsulated materials and controlled release

    Science.gov (United States)

    Anumansirikul, Nattaporm; Wittayasuporn, Mayura; Klinubol, Patcharawalai; Tachaprutinun, A.; Wanichwecharungruang, Supason P.

    2008-05-01

    Methyl ether terminated poly(ethylene glycol)-4-methoxycinnamoylphthaloylchitosan (PCPLC), a UV absorptive polymer, and methyl ether terminated poly(ethylene glycol)-phthaloylchitosan (PPLC) were synthesized, characterized and self-assembled into stable water-dispersible spherical nanoparticles. The encapsulation of a model compound, 2-ethylhexyl-4-methoxycinnamate (EHMC), was carried out to give particles with 67% (w/w) EHMC loading. The E to Z photoisomerization of EHMC encapsulated inside both particles was monitored and compared to non-encapsulated EHMC. Minimal E to Z photoisomerization was observed when EHMC was encapsulated in PCPLC particles prepared from a polymer with a maximum degree of 4-methoxycinnamoyl substitution. The results indicated that the grafted UVB absorptive chromophore, 4-methoxycinnamoyl moieties, situated at the shell of PCPLC nanoparticles acted as a UV-filtering barrier, protecting the encapsulated EHMC from the UVB radiation, thus minimizing its photoisomerization. In vitro experiments revealed the pH-dependent controlled release of EHMC from PCPLC and PPLC particles. Ex vivo experiments, using a Franz diffusion cell with baby mouse skin, indicated that neither PPLC nor PCPLC particles could penetrate the skin into the receptor medium after a 24 h topical application. When applied on the baby mouse skin, both EHMC-encapsulated PPLC and EHMC-encapsulated PCPLC showed comparable controlled releases of the EHMC. The released EHMC could transdermally penetrate the baby mouse skin.

  10. Stabilization of Phenylalanine Ammonia Lyase from Rhodotorula glutinis by Encapsulation in Polyethyleneimine-Mediated Biomimetic Silica.

    Science.gov (United States)

    Cui, Jiandong; Liang, Longhao; Han, Cong; Lin Liu, Rong

    2015-06-01

    Phenylalanine ammonia lyase (PAL) from Rhodotorula glutinis was encapsulated within polyethyleneimine-mediated biomimetic silica. The main factors in the preparation of biomimetic silica were optimized by response surface methodology (RSM). Compared to free PAL (about 2 U), the encapsulated PAL retained more than 43 % of their initial activity after 1 h of incubation time at 60 °C, whereas free PAL lost most of activity in the same conditions. It was clearly indicated that the thermal stability of PAL was improved by encapsulation. Moreover, the encapsulated PAL exhibited the excellent stability of the enzyme against denaturants and storage stability, and pH stability was improved by encapsulation. Operational stability of 7 reaction cycles showed that the encapsulated PAL was stable. Nevertheless, the K m value of encapsulated PAL in biomimetic silica was higher than that of the free PAL due to lower total surface area and increased mass transfer resistance.

  11. Preparation and structure of carbon encapsulated copper nanoparticles

    International Nuclear Information System (INIS)

    Hao Chuncheng; Xiao Feng; Cui Zuolin

    2008-01-01

    Carbon-encapsulated copper nanoparticles were synthesized by a modified arc plasma method using methane as carbon source. The particles were characterized in detail by transmission electron microscope, high-resolution transmission electron microscopy, selected-area electron diffraction, X-ray diffraction, thermogravimetric and differential scanning calorimetry. The encapsulated copper nanoparticles were about 30 nm in diameter with 3-5 nm graphitic carbon shells. The outside graphitic carbon layers effectively prevented unwanted oxidation of the copper inside. The effect of the ratio of He/CH 4 on the morphologies and the formation of the carbon shell were investigated

  12. Oxidation of Bioethanol using Zeolite-Encapsulated Gold Nanoparticles

    DEFF Research Database (Denmark)

    Mielby, Jerrik Jørgen; Abildstrøm, Jacob Oskar; Wang, Feng

    2014-01-01

    With the ongoing developments in biomass conversion, the oxidation of bioethanol to acetaldehyde may become a favorable and green alternative to the preparation from ethylene. Here, a simple and effective method to encapsulate gold nanoparticles in zeolite silicalite-1 is reported and their high...... zeolite crystals comprise a broad range of mesopores and contain up to several hundred gold nanoparticles with a diameter of 2-3nm that are distributed inside the zeolites rather than on the outer surface. The encapsulated nanoparticles have good stability and result in 50% conversion of ethanol with 98...

  13. Oxidation of Bioethanol using Zeolite-Encapsulated Gold Nanoparticles

    DEFF Research Database (Denmark)

    Mielby, Jerrik Jørgen; Abildstrøm, Jacob Oskar; Wang, Feng

    2014-01-01

    With the ongoing developments in biomass conversion, the oxidation of bioethanol to acetaldehyde may become a favorable and green alternative to the preparation from ethylene. Here, a simple and effective method to encapsulate gold nanoparticles in zeolite silicalite‐1 is reported and their high...... zeolite crystals comprise a broad range of mesopores and contain up to several hundred gold nanoparticles with a diameter of 2–3 nm that are distributed inside the zeolites rather than on the outer surface. The encapsulated nanoparticles have good stability and result in 50 % conversion of ethanol with 98...

  14. Poly(lactide-co-glycolide) encapsulated hydroxyapatite microspheres for sustained release of doxycycline

    Energy Technology Data Exchange (ETDEWEB)

    Wang Xiaoyun [School of Pharmacy, Shenyang Pharmaceutical University, 103, Wenhua Road, Shenyang 110016 (China); Department of Pharmacy, Shandong Drug and Food Vocational College, Science and Technology Town, Hightech Industrial Development Zone, Weihai 264210 (China); Xu Hui; Zhao Yanqiu [School of Pharmacy, Shenyang Pharmaceutical University, 103, Wenhua Road, Shenyang 110016 (China); Wang Shaoning, E-mail: wsn-xh@126.com [School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103, Wenhua Road, Shenyang 110016 (China); Abe, Hiroya; Naito, Makio [Joining and Welding Research Institute, Osaka University, 11-1, Mihogaoka, Ibaraki, Osaka 567-0047 (Japan); Liu Yanli [School of Pharmacy, Shenyang Pharmaceutical University, 103, Wenhua Road, Shenyang 110016 (China); Wang Guoqing [School of Pharmaceutical Engineering, Shenyang Pharmaceutical University, 103, Wenhua Road, Shenyang 110016 (China)

    2012-03-15

    Highlights: Black-Right-Pointing-Pointer PLGA encapsulated HAP-MSs were used for the sustained delivery of Doxycycline (Doxy, a broad spectrum tetracycline antibiotic). Black-Right-Pointing-Pointer Sustained Doxy release without obvious burst was observed. Black-Right-Pointing-Pointer Mechanism of the sustained Doxy release was illustrated. Black-Right-Pointing-Pointer Sustained Doxy release character in vivo was also obtained, the plasma Doxy levels were relatively lower and steady compared to that of the un-encapsulated HAP-MSs. - Abstract: The purpose of this study was to prepare a poly(lactide-co-glycolide) (PLGA) encapsulated hydroxyapatite microspheres (HAP-MSs) as injectable depot for sustained delivery of Doxycycline (Doxy). Doxy loaded HAP-MSs (Doxy-HAP-MSs) were encapsulated with PLGA by solid-in-oil-in-water (S/O/W) emulsion-solvent evaporation technique, the effects of the PLGA used (various intrinsic viscosity and LA/GA ratio) and ratio of PLGA/HAP-MSs on the formation of Doxy-HAP-MSs and in vitro release of Doxy were studied. The results showed that sustained drug release without obvious burst was obtained by using PLGA encapsulated HAP-MSs as the carrier, also the drug release rate could be tailored by changing the ratio of PLGA/HAP-MSs, or PLGA of various intrinsic viscosities or LA/GA ratio. Lower ratio of PLGA/HAP-MSs corresponded faster Doxy release, e.g. for the microspheres of PLGA/HAP-MSs ratio of 8 and 0.25, the in vitro Doxy release percents at the end of 7days were about 23% and 76%, respectively. Higher hydrophilicity (higher ratio of GA to LA) and lower molecular weight of PLGA corresponded to higher Doxy release rates. For in vivo release study, PLGA encapsulated HAP-MSs were subcutaneously injected to the back of mice, and the results showed good correlation between the in vivo and in vitro drug release. Meanwhile, the plasma Doxy levels after subcutaneous administration of PLGA encapsulated Doxy-HAP-MSs were relatively lower and steady

  15. Charge transfer in conjugated oligomers encapsulated into carbon nanotubes

    Energy Technology Data Exchange (ETDEWEB)

    Almadori, Y.; Alvarez, L.; Michel, T.; Le Parc, R.; Bantignies, J.L.; Hermet, P.; Sauvajol, J.L. [Laboratoire Charles Coulomb UMR 5521, Universite Montpellier 2, 34095 Montpellier (France); Laboratoire Charles Coulomb UMR 5521, CNRS, 34095 Montpellier (France); Arenal, R. [Laboratoire d' Etude des Microstructures, CNRS-ONERA, 92322 Chatillon (France); Laboratorio de Microscopias Avanzadas, Instituto de Nanociencia de Aragon, U. Zaragoza, 50018 Zaragoza (Spain); Babaa, R. [Laboratoire de Chimie des Surfaces et Interfaces, CEA, IRAMIS, SPCSI, 91191 Gif-sur-Yvette Cedex (France); Chemical Engineering Department, University of Technology PETRONAS, UTP, Ipoh-Perak (Malaysia); Jouselme, B.; Palacin, S. [Laboratoire de Chimie des Surfaces et Interfaces, CEA, IRAMIS, SPCSI, 91191 Gif-sur-Yvette Cedex (France)

    2011-11-15

    This study deals with a hybrid system consisting in quaterthiophene derivative encapsulated inside single-walled and multi-walled carbon nanotubes. Investigations of the encapsulation step are performed by transmission electron microscopy. Raman spectroscopy data point out different behaviors depending on the laser excitation energy with respect to the optical absorption of quaterthiophene. At low excitation energy (far from the oligomer resonance window) there is no significant modification of the Raman spectra before and after encapsulation. By contrast, at high excitation energy (close to the oligomer resonance window), Raman spectra exhibit a G-band shift together with an important RBM intensity loss, suggesting a significant charge transfer between the inserted molecule and the host nanotubes. Those results suggest a photo induced process leading to a significant charge transfer. (Copyright copyright 2011 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

  16. Elevating bioavailability of curcumin via encapsulation with a novel formulation of artificial oil bodies.

    Science.gov (United States)

    Chang, Ming-Tsung; Tsai, Tong-Rong; Lee, Chun-Yann; Wei, Yu-Sheng; Chen, Ying-Jie; Chen, Chun-Ren; Tzen, Jason T C

    2013-10-09

    Utilization of curcumin has been limited due to its poor oral bioavailability. Oral bioavailability of hydrophobic compounds might be elevated via encapsulation in artificial seed oil bodies. This study aimed to improve oral bioavailability of curcumin via this encapsulation. Unfortunately, curcumin was indissoluble in various seed oils. A mixed dissolvent formula was used to dissolve curcumin, and the admixture was successfully encapsulated in artificial oil bodies stabilized by recombinant sesame caleosin. The artificial oil bodies of relatively small sizes (150 nm) were stably solidified in the forms of powder and tablet. Oral bioavailability of curcumin with or without encapsulation in artificial oil bodies was assessed in Sprague-Dawley male rats. The results showed that encapsulation of curcumin significantly elevated its bioavailability and provided the highest maximum whole blood concentration (Cmax), 37 ± 28 ng/mL, in the experimental animals 45 ± 17 min (t(max)) after oral administration. Relative bioavailability calculated on the basis of the area under the plasma concentration-time curve (AUC) was increased by 47.7 times when curcumin was encapsulated in the artificial oil bodies. This novel formulation of artificial oil bodies seems to possess great potential to encapsulate hydrophobic drugs for oral administration.

  17. Design and characterization of a 3D encapsulation with silicon vias for radio frequency micro-electromechanical system resonator

    International Nuclear Information System (INIS)

    Zhao Ji-Cong; Yuan Quan; Wang Feng-Xiang; Kan Xiao; Han Guo-Wei; Yang Jin-Ling; Yang Fu-Hua; Sun Ling; Sun Hai-Yan

    2017-01-01

    In this paper, we present a three-dimensional (3D) vacuum packaging technique at a wafer level for a radio frequency micro-electromechanical system (RF MEMS) resonator, in which low-loss silicon vias is used to transmit RF signals. Au–Sn solder bonding is adopted to provide a vacuum encapsulation as well as electrical conductions. A RF model of the encapsulation cap is established to evaluate the parasitic effect of the packaging, which provides an effective design solution of 3D RF MEMS encapsulation. With the proposed packaging structure, the signal-to-background ratio (SBR) of 24 dB is achieved, as well as the quality factor ( Q -factor) of the resonator increases from 8000 to 10400 after packaging. The packaged resonator has a linear frequency–temperature ( f – T ) characteristic in a temperature range between 0 °C and 100 °C. And the package shows favorable long-term stability of the Q -factor over 200 days, which indicates that the package has excellent hermeticity. Furthermore, the average shear strength is measured to be 43.58 MPa among 10 samples. (paper)

  18. Encapsulation of resveratrol in spherical particles of food grade hydrogels

    Directory of Open Access Journals (Sweden)

    Balanč Bojana D.

    2017-01-01

    Full Text Available The paper reports about the preparation and characterization of hydrogel particles containing liposomes loaded with resveratrol as an active compound. The materials used for preparation of the particles were chosen to be suitable for food industry. Different polymer concentrations affect particles shape, size, size distribution, as well as the release kinetics of resveratrol. The diameter of particles varied from 360 to 754 μm, while the narrow size distribution was observed for all types of particles. Release studies were performed in Franz diffusion cell and the results showed the prolonged release of resveratrol from all samples, but the sample with the highest content of polymer (2.5% w/w in particular stood out. The research provides useful information about liposomes containing active compound encapsulated in hydrogel matrices and offers the basis for its application in the food industry.

  19. Improvement of Stability and Antioxidant Activities by Using Phycocyanin - Chitosan Encapsulation Technique

    Science.gov (United States)

    Suzery, Meiny; Hadiyanto; Majid, Dian; Setyawan, Deny; Sutanto, Heri

    2017-02-01

    Encapsulation is a coating process to improve the stability of bioactive compounds. Phycocyanin with high antioxidant activity has been encapsulated with chitosan in microcapsules form. In this study aims to determine the best conditions in the encapsulation process using the extrusion method, characterization of the physicochemical properties of the microcapsules, antioxidant activity test using DPPH, in vitro release performance and evaluate the storage stability against temperature. The results of the encapsulation process is obtained: Na-TPP is better than Na-citrate as crosslinker and chitosan content 3% as a coating with ratio of chitosan to phycocyanin ratio 1: 1. Test of antioxidant activity also showed encapsulation with chitosan content 3% has the highest antioxidant activity. Morphological analysis microcapsules were found to have compact spherical shape with diameter range 900-1000 µm. In vitro release testing showed a quick release in an acidic environment (SGF) for 2 hours and slowly release under alkaline conditions (SIF) for 8 hours under mechanical stirring at 37°C. Phycocyanin much more stable against temperature during storage in microcapsules.

  20. Fluorescent probe encapsulated hydrogel microsphere for selective and reversible detection of Hg{sup 2+}

    Energy Technology Data Exchange (ETDEWEB)

    Song, Zhenhu; Wang, Fang; Qiang, Jian; Zhang, Zhijie; Chen, Yahui; Wang, Yong; Zhang, Wei; Chen, Xiaoqiang

    2017-03-15

    We developed a simple and sensitive hydrogel sensor in the form of microspheres by using fluorescence probe encapsulated within a hydrogel matrix for the detection of Hg{sup 2+}. The traditional fluorescence probes suspended in solution are not transportable and recoverable. To overcome these disadvantages, we devised poly(ethylene glycol) diacrylate-based hydrogel microspheres in which fluorescence probe (R19S) was embedded at high density. The functionalized hydrogel microspheres were prepared by combining a microfluidic device with UV light. The hydrogel microspheres-based sensor exhibited good selectivity to Hg{sup 2+} among various metal ions and high sensitivity with a detection limit of 90 nM. Furthermore, after binding with Hg{sup 2+}, the R19S encapsulated hydrogel microspheres can be separated from testing samples easily and treated with the solution containing KI to remove Hg{sup 2+} and realize reusable detection. The current work may offer a new method for Hg{sup 2+} recognition with a more efficient manner.

  1. SERS active Ag encapsulated Fe@SiO2 nanorods in electromagnetic wave absorption and crystal violet detection.

    Science.gov (United States)

    Senapati, Samarpita; Srivastava, Suneel Kumar; Singh, Shiv Brat; Kulkarni, Ajit R

    2014-11-01

    The present work is focused on the preparation of Fe nanorods by the chemical reduction of FeCl3 (aq) using NaBH4 in the presence of glycerol as template followed by annealing of the product at 500°C in the presence of H2 gas flow. Subsequently, its surface has been modified by silica followed by silver nanoparticles to form silica coated Fe (Fe@SiO2) and Ag encapsulated Fe@SiO2 nanostructure employing the Stöber method and silver mirror reaction respectively. XRD pattern of the products confirmed the formation of bcc phase of iron and fcc phase of silver, though silica remained amorphous. FESEM images established the growth of iron nanorods from the annealed product and also formation of silica and silver coating on its surface. The appearance of the characteristics bands in FTIR confirmed the presence of SiO2 on the Fe surface. Magnetic measurements at room temperature indicated the ferromagnetic behavior of as prepared iron nanorods, Fe@SiO2 and silver encapsulated Fe@SiO2 nanostructures. All the samples exhibited strong microwave absorption property in the high frequency range (10GHz), though it is superior for Ag encapsulated Fe@SiO2 (-14.7dB) compared with Fe@SiO2 (-9.7dB) nanostructures of the same thickness. The synthesized Ag encapsulated Fe@SiO2 nanostructure also exhibited the SERS phenomena, which is useful in the detection of the carcinogenic dye crystal violet (CV) upto the concentration of 10(-10)M. All these findings clearly demonstrate that the Ag encapsulated Fe@SiO2 nanostructure could efficiently be used in the environmental remediation. Copyright © 2014 Elsevier Inc. All rights reserved.

  2. Mercuric iodide semiconductor detectors encapsulated in polymeric resin

    Energy Technology Data Exchange (ETDEWEB)

    Martins, Joao F. Trencher; Santos, Robinson A. dos; Ferraz, Caue de M.; Oliveira, Adriano S.; Velo, Alexandre F.; Mesquita, Carlos H. de; Hamada, Margarida M., E-mail: mmhamada@ipen.br [Instituto de Pesquisas Energeticas e Nucleares (IPEN/CNEN-SP), Sao Paulo, SP (Brazil); Disch, Christian; Fiederle, Michael [Albert-Ludwigs Universität Freiburg - UniFreibrug, Freiburg Materials Research Center - FMF, Freiburg (Germany)

    2015-07-01

    The development of new semiconductor radiation detectors always finds many setback factors, such as: high concentration of impurities in the start materials, poor long term stability, the surface oxidation and other difficulties discussed extensively in the literature, that limit their use. In this work was studied, the application of a coating resin on HgI2 detectors, in order to protect the semiconductor crystal reactions from atmospheric gases and to isolate electrically the surface of the crystals. Four polymeric resins were analyzed: Resin 1: 50% - 100%Heptane, 10% - 25% methylcyclohexane, <1% cyclohexane; Resin 2: 25% - 50% ethanol, 25% - 50% acetone, <2,5% ethylacetate; Resin 3: 50% - 100% methylacetate, 5% - 10% n-butylacetate; Resin 4: 50% - 100% ethyl-2-cyanacrylat. The influence of the polymeric resin type used on the spectroscopic performance of the HgI{sub 2} semiconductor detector is, clearly, demonstrated. The better result was found for the detector encapsulated with Resin 3. An increase of up to 26 times at the stability time was observed for the detectors encapsulated compared to that non-encapsulated detector. (author)

  3. Encapsulation of pancreatic islets for transplantation in diabetes : the untouchable islets

    NARCIS (Netherlands)

    de Vos, P; Marchetti, P

    The aim of encapsulation of pancreatic islets is to transplant in the absence of immunosuppression. It is based on the principle that transplanted tissue is protected from the host immune system by an artificial membrane. Encapsulation allows for application of insulin-secreting cells of animal or

  4. The opto-thermal effect on encapsulated cholesteric liquid crystals

    Science.gov (United States)

    Liu, Yu-Sung; Lin, Hui-Chi; Yang, Kin-Min

    2017-12-01

    In this study, we implemented a micro-encapsulated CLC electronic paper that is optically addressed and electrically erasable. The mechanism that forms spot diameters on the CLC films is discussed and verified through various experimental parameters, including the thickness of CLCs and Poly(2,3-dihydrothieno-1,4-dioxin)-poly(styrenesulfonate) (PEDOT:PSS), pump intensity, and pumping time. The opto-thermal effect, brought on by the PEDOT:PSS absorbing layer, causes the spot diameters on the cholesteric liquid crystal thin films to vary. According to our results, the spot diameter is larger for a sample with a thinner cholesteric liquid crystal layer with the same excitation conditions and same thickness of the PEDOT layer. The spot diameter is also larger for a sample with a thicker PEDOT under the same excitation conditions and same thickness of the cholesteric liquid crystal layer. We proposed a simple heat-conducting model to explain the experimental results, which qualitatively agree with this theoretical model.

  5. Encapsulation of Antifouling Organic Biocides in Poly(lactic acid) Nanoparticles.

    Science.gov (United States)

    Kamtsikakis, Aristotelis; Kavetsou, Eleni; Chronaki, Konstantina; Kiosidou, Evangelia; Pavlatou, Evangelia; Karana, Alexandra; Papaspyrides, Constantine; Detsi, Anastasia; Karantonis, Antonis; Vouyiouka, Stamatina

    2017-09-26

    The scope of the current research was to assess the feasibility of encapsulating three commercial antifouling compounds, Irgarol 1051, Econea and Zinc pyrithione, in biodegradable poly(lactic acid) (PLA) nanoparticles. The emulsification-solvent evaporation technique was herein utilized to manufacture nanoparticles with a biocide:polymer ratio of 40%. The loaded nanoparticles were analyzed for their size and size distribution, zeta potential, encapsulation efficiency and thermal properties, while the relevant physicochemical characteristics were correlated to biocide-polymer system. In addition, the encapsulation process was scaled up and the prepared nanoparticles were dispersed in a water-based antifouling paint in order to examine the viability of incorporating nanoparticles in such coatings. Metallic specimens were coated with the nanoparticles-containing paint and examined regarding surface morphology.

  6. Enhanced structural stability of DNA origami nanostructures by graphene encapsulation

    International Nuclear Information System (INIS)

    Matković, Aleksandar; Vasić, Borislav; Pešić, Jelena; Gajić, Radoš; Prinz, Julia; Bald, Ilko; Milosavljević, Aleksandar R

    2016-01-01

    We demonstrate that a single-layer graphene replicates the shape of DNA origami nanostructures very well. It can be employed as a protective layer for the enhancement of structural stability of DNA origami nanostructures. Using the AFM based manipulation, we show that the normal force required to damage graphene encapsulated DNA origami nanostructures is over an order of magnitude greater than for the unprotected ones. In addition, we show that graphene encapsulation offers protection to the DNA origami nanostructures against prolonged exposure to deionized water, and multiple immersions. Through these results we demonstrate that graphene encapsulated DNA origami nanostructures are strong enough to sustain various solution phase processing, lithography and transfer steps, thus extending the limits of DNA-mediated bottom-up fabrication. (paper)

  7. Encapsulation of Antifouling Organic Biocides in Poly(lactic acid) Nanoparticles

    Science.gov (United States)

    Kamtsikakis, Aristotelis; Kavetsou, Eleni; Chronaki, Konstantina; Kiosidou, Evangelia; Pavlatou, Evangelia; Karana, Alexandra; Papaspyrides, Constantine; Detsi, Anastasia; Karantonis, Antonis; Vouyiouka, Stamatina

    2017-01-01

    The scope of the current research was to assess the feasibility of encapsulating three commercial antifouling compounds, Irgarol 1051, Econea and Zinc pyrithione, in biodegradable poly(lactic acid) (PLA) nanoparticles. The emulsification–solvent evaporation technique was herein utilized to manufacture nanoparticles with a biocide:polymer ratio of 40%. The loaded nanoparticles were analyzed for their size and size distribution, zeta potential, encapsulation efficiency and thermal properties, while the relevant physicochemical characteristics were correlated to biocide–polymer system. In addition, the encapsulation process was scaled up and the prepared nanoparticles were dispersed in a water-based antifouling paint in order to examine the viability of incorporating nanoparticles in such coatings. Metallic specimens were coated with the nanoparticles-containing paint and examined regarding surface morphology. PMID:28952560

  8. Preliminary Hazards Analysis of K-Basin Fuel Encapsulation and Storage

    International Nuclear Information System (INIS)

    Strickland, G.C.

    1994-01-01

    This Preliminary Hazards Analysis (PHA) systematically examines the K-Basin facilities and their supporting systems for hazards created by abnormal operating conditions and external events (e.g., earthquakes) which have the potential for causing undesirable consequences to the facility worker, the onsite individual, or the public. The operational activities examined are fuel encapsulation, fuel storage and cooling. Encapsulation of sludges in the basins is not examined. A team of individuals from Westinghouse produced a set of Hazards and Operability (HAZOP) tables documenting their examination of abnormal process conditions in the systems and activities examined in K-Basins. The purpose of this report is to reevaluate and update the HAZOP in the original Preliminary Hazard Analysis of K-Basin Fuel Encapsulation and Storage originally developed in 1991

  9. Dysprosium Acetylacetonato Single-Molecule Magnet Encapsulated in Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Ryo Nakanishi

    2016-12-01

    Full Text Available Dy single-molecule magnets (SMMs, which have several potential uses in a variety of applications, such as quantum computing, were encapsulated in multi-walled carbon nanotubes (MWCNTs by using a capillary method. Encapsulation was confirmed by using transmission electron microscopy (TEM. In alternating current magnetic measurements, the magnetic susceptibilities of the Dy acetylacetonato complexes showed clear frequency dependence even inside the MWCNTs, meaning that this hybrid can be used as magnetic materials in devices.

  10. Enhanced Sampling and Analysis, Selection of Technology for Testing

    Energy Technology Data Exchange (ETDEWEB)

    Svoboda, John; Meikrantz, David

    2010-02-01

    The focus of this study includes the investigation of sampling technologies used in industry and their potential application to nuclear fuel processing. The goal is to identify innovative sampling methods using state of the art techniques that could evolve into the next generation sampling and analysis system for metallic elements. This report details the progress made in the first half of FY 2010 and includes a further consideration of the research focus and goals for this year. Our sampling options and focus for the next generation sampling method are presented along with the criteria used for choosing our path forward. We have decided to pursue the option of evaluating the feasibility of microcapillary based chips to remotely collect, transfer, track and supply microliters of sample solutions to analytical equipment in support of aqueous processes for used nuclear fuel cycles. Microchip vendors have been screened and a choice made for the development of a suitable microchip design followed by production of samples for evaluation by ANL, LANL, and INL on an independent basis.

  11. Amperometric glucose biosensor based on layer-by-layer films of microperoxidase-11 and liposome-encapsulated glucose oxidase.

    Science.gov (United States)

    Graça, J S; de Oliveira, R F; de Moraes, M L; Ferreira, M

    2014-04-01

    An important step in several bioanalytical applications is the immobilization of biomolecules. Accordingly, this procedure must be carefully chosen to preserve their biological structure and fully explore their properties. For this purpose, we combined the versatility of the layer-by-layer (LbL) method for the immobilization of biomolecules with the protective behavior of liposome-encapsulated systems to fabricate a novel amperometric glucose biosensor. To obtain the biosensing unit, an LbL film of the H2O2 catalyst polypeptide microperoxidase-11 (MP-11) was assembled onto an indium-tin oxide (ITO) electrode followed by the deposition of a liposome-encapsulated glucose oxidase (GOx) layer. The biosensor response toward glucose detection showed a sensitivity of 0.91±0.09 (μA/cm2)/mM and a limit of detection (LOD) of 8.6±1.1 μM, demonstrating an improved performance compared to similar biosensors with a single phospholipid-liposome or even containing a non-encapsulated GOx layer. Finally, glucose detection was also performed in a zero-lactose milk sample to demonstrate the potential of the biosensor for food analysis. Copyright © 2014 Elsevier B.V. All rights reserved.

  12. Safeguards by Design at the Encapsulation Plant in Finland

    International Nuclear Information System (INIS)

    Ingegneri, M.; Baird, K.; Park, W.-S.; Coyne, J.M.; Enkhjin, L.; Chew, L.S.; Plenteda, R.; Sprinkle, J.; Yudin, Y.; Ciuculescu, C.; Koutsoyannopoulos, C.; Murtezi, M.; Schwalbach, P.; Vaccaro, S.; Pekkarinen, J.; Thomas, M.; Zein, A.; Honkamaa, T.; Hamalainen, M.; Martikka, E.; Moring, M.; Okko, O.

    2015-01-01

    Finland has launched a spent fuel disposition project to encapsulate all of its spent fuel assemblies and confine the disposal canisters in a deep geological repository. The construction of the underground premises started several years ago with the drilling, blasting and reinforcement of tunnels and shafts to ensure the safe deep underground construction and disposal techniques in the repository, while the design of the encapsulation plant (EP) enters the licencing phase preliminary to its construction. The spent fuel assemblies, which have been safeguarded for decades at the nuclear power plants, are going to be transported to the EP, loaded into copper canisters and stored in underground tunnels where they become inaccessible after backfilling. Safeguards measures are needed to ensure that final spent fuel verification is performed before its encapsulation and that no nuclear material is diverted during the process. This is an opportunity for the inspectorates to have the infrastructure necessary for the safeguards equipment incorporated in the design of the encapsulation plant before licencing for construction occurs. The peculiarity of this project is that it is going to run for more than a century. Therefore, significant changes are to be expected in the technical capabilities available for implementing safeguards (e.g., verification techniques and instruments), as well as in the process itself, e.g., redesign for the encapsulation of future fuel types. For these reasons a high degree of flexibility is required in order to be able to shift to different solutions at a later stage while minimizing the interference with the licencing process and facility operations. This paper describes the process leading to the definition of the technical requirements by IAEA and Euratom to be incorporated in the facility's design. (author)

  13. Development, testing, and demonstration of geotechnical and cement-based encapsulant materials for the stabilization of radioactive and hazardous waste disposal structures

    International Nuclear Information System (INIS)

    Phillips, S.J.; Cammann, J.W.; Benny, H.L.; Serne, R.J.; Martin, P.F.; Ames, L.L.

    1991-09-01

    A zeolite fluidized-bed treatment system is being developed and tested for the treatment of radioactive and hazardous waste-contaminated subsurface disposal structures. Formulations of cement, fly ash, and slag slurries and sequestering agents also are being tested and evaluated. Leach resistance of radionuclides, heavy metals, and hazardous inorganic compounds in the solidified cement-based encapsulant has been determined. These results simulate the resistance to water leaching of the solidified product after it has been injected an open and interstitial void volume in and proximal to liquid waste disposal structures. Micro- and macro-encapsulation of contaminants within and geologic media surrounding subsurface disposal structures is being demonstrated as an alternative technology for waste site remediation. 5 refs., 1 fig., 1 tab

  14. Photoinduced charge transfer within polyaniline-encapsulated quantum dots decorated on graphene.

    Science.gov (United States)

    Nguyen, Kim Truc; Li, Dehui; Borah, Parijat; Ma, Xing; Liu, Zhaona; Zhu, Liangliang; Grüner, George; Xiong, Qihua; Zhao, Yanli

    2013-08-28

    A new method to enhance the stability of quantum dots (QDs) in aqueous solution by encapsulating them with conducting polymer polyaniline was reported. The polyaniline-encapsulated QDs were then decorated onto graphene through π-π interactions between graphene and conjugated polymer shell of QDs, forming stable polyaniline/QD/graphene hybrid. A testing electronic device was fabricated using the hybrid in order to investigate the photoinduced charge transfer between graphene and encapsulated QDs within the hybrid. The charge transfer mechanism was explored through cyclic voltammetry and spectroscopic studies. The hybrid shows a clear response to the laser irradiation, presenting a great advantage for further applications in optoelectronic devices.

  15. Impact of culture conditions on β-carotene encapsulation using Yarrowia lipolytica cells

    Science.gov (United States)

    Dang, Tran Hai; Minh, Ho Thi Thu; Van Nhi, Tran Nguyen; Ngoc, Ta Thi Minh

    2017-09-01

    Yeast cell was reported as an effective natural preformed material for use in encapsulation of hydrophobic compounds. The encapsulation process was normally considered as passive transfer through cellular wall and cellular membrane. Beside solubility of hydrophobic compound in phospholipid membrane or plasmolysis, membrane characteristics of yeast cell which are differed between strains and influenced by culture conditions are main factors involving the accumulation of hydrophobic compound into yeast cell. In this study, the oleaginous yeast Yarrowia lipolytica was used as micro-container shell to encapsulate a high hydrophobic compound - β-carotene. Yeast cell was cultured under different conditions and wet yeast biomass was incubated with β-carotene which was dissolved in soybean oil overnight. β-carotene accumulation was then extracted and evaluated by UV-VIS spectrometry. Optimization of culture condition was investigated using the Box-Behnken model. β-carotene encapsulation efficiency in Y. lipolytica was showed to be affected by both pH of medium and agitation conditions. The highest β-carotene encapsulation efficiency was optimized at 42.8 μg/g with Y. lipolytica cultured at pH 4.5, medium volume equal to 115 ml and agitation speed at 211 rpm.

  16. Characterization of Encapsulated Corrosion Inhibitors Containing Microparticles for Environmentally Friendly Smart Coatings

    Science.gov (United States)

    Pearman, Benjamin Pieter; Calle, Luz M.

    2015-01-01

    This poster presents the results obtained from experiments designed to evaluate the release properties, as well as the corrosion inhibition effectiveness, of several encapsulated corrosion inhibitors. Microencapsulation has been used in the development of environmentally friendly multifunctional smart coatings. This technique enables the incorporation of autonomous corrosion detection, inhibition and self-healing functionalities into many commercially available coating systems. Select environmentally friendly corrosion inhibitors were encapsulated in organic and inorganic pH-sensitive microparticles and their release in basic solutions was studied. The release rate results showed that the encapsulation can be tailored from fast, for immediate corrosion protection, to slow, which will provide continued long-term corrosion protection. The incorporation of several corrosion inhibitor release profiles into a coating provides effective corrosion protection properties. To investigate the corrosion inhibition efficiency of the encapsulated inhibitors, electrochemical techniques were used to obtain corrosion potential, polarization curve and polarization resistance data. These measurements were performed using the free as well as the encapsulated inhibitors singly or in combinations. Results from these electrochemical tests will be compared to those obtained from weight loss and other accelerated corrosion experiments.

  17. Encapsulating spent nuclear fuel

    International Nuclear Information System (INIS)

    Fleischer, L.R.; Gunasekaran, M.

    1979-01-01

    A system is described for encapsulating spent nuclear fuel discharged from nuclear reactors in the form of rods or multi-rod assemblies. The rods are completely and contiguously enclosed in concrete in which metallic fibres are incorporated to increase thermal conductivity and polymers to decrease fluid permeability. This technique provides the advantage of acceptable long-term stability for storage over the conventional underwater storage method. Examples are given of suitable concrete compositions. (UK)

  18. The effect of colloidal silica nanoparticles encapsulated fluorescein dye using micelle entrapment method

    Science.gov (United States)

    Ahmad, Atiqah; Zakaria, Nor Dyana; Lockman, Zainovia; Razak, Khairunisak Abdul

    2018-05-01

    The advancement of nanoparticle-based approaches such as quantum dots (QDs), metallic (Au and Ag) NPs, silica NPs and other types of nanomaterial have led to a large variety of biomolecular imaging and labelling reagents with controlled size and shaped to overcome the limitation of conventional organic dye. In this study, the yellowish green color of fluorescein dye was encapsulated into colloidal silica nanoparticles by using micelle entrapment approach. Two different size of silica nanoparticles encapsulated fluorescein dye (27.7 ± 5.6 and 46.73 ± 4.3 nm) with spherical and monodispered of nanoparticles were synthesised by varying the volume of co-solvent during the synthesis process. The particles size, particles morphology, absorption spectrum and the photostability of fluorescein dye was measured by using dynamic light scaterring (DLS), Transmission Electron Microscope (TEM) and UV-Vis spectrometer. Furthermore, the effect of photostability of of silica nanoparticles encapsulated fluorescein dye was measured under radiation of 200 W of Halogen lamp for 60 minutes. The silica nanoparticles encapsulated fluorescein dye was more stable compared to bare fluorescein dye after the exposure. In conclusion, the photostability of silica nanoparticles encapsulated fluorescein dye was improved compared to bare fluorescein dye, thus silica nanoparticles encapsulation successfully provides protection from the photobleaching and photodegradation of fluorescein dye.

  19. Effect of Encapsulation on Antimicrobial Activity of Herbal Extracts with Lysozyme

    Directory of Open Access Journals (Sweden)

    Petra Matouskova

    2016-01-01

    Full Text Available Resistance of microorganisms to antibiotics has increased. The use of natural components with antimicrobial properties can be of great significance to reduce this problem. The presented work is focused on the study of the effect of encapsulation of selected plant and animal antimicrobial substances (herbs, spices, lysozyme and nisin on their activity and stability. Antimicrobial components were packaged into liposomes and polysaccharide particles (alginate, chitosan and starch. Antimicrobial activity was tested against two Gram-positive (Bacillus subtilis and Micrococcus luteus and two Gram-negative (Escherichia coli and Serratia marcescens bacteria. Encapsulation was successful in all types of polysaccharide particles and liposomes. The prepared particles exhibited very good long-term stability, especially in aqueous conditions. Antimicrobial activity was retained in all types of particles. Liposomes with encapsulated herb and spice extracts exhibited very good inhibitory effect against all tested bacterial strains. Most of herbal extracts had very good antimicrobial effect against the tested Gram-negative bacterial strains, while Gram-positive bacteria were more sensitive to lysozyme particles. Thus, particles with co-encapsulated herbs and lysozyme are more active against different types of bacteria, and more stable and more effective during long-term storage. Particles with encapsulated mixture of selected plant extracts and lysozyme could be used as complex antimicrobial preparation with controlled release in the production of food and food supplements, pharmaceutical and cosmetic industries.

  20. Synthesis of Polyamidoamine Dendrimer for Encapsulating Tetramethylscutellarein for Potential Bioactivity Enhancement.

    Science.gov (United States)

    Shadrack, Daniel M; Mubofu, Egid B; Nyandoro, Stephen S

    2015-11-04

    The biomedical potential of flavonoids is normally restricted by their low water solubility. However, little has been reported on their encapsulation into polyamidoamine (PAMAM) dendrimers to improve their biomedical applications. Generation four (G4) PAMAM dendrimer containing ethylenediaminetetraacetic acid core with acrylic acid and ethylenediamine as repeating units was synthesized by divergent approach and used to encapsulate a flavonoid tetramethylscutellarein (TMScu, 1) to study its solubility and in vitro release for potential bioactivity enhancement. The as-synthesized dendrimer and the dendrimer-TMScu complex were characterized by spectroscopic and spectrometric techniques. The encapsulation of 1 into dendrimer was achieved by a co-precipitation method with the encapsulation efficiency of 77.8% ± 0.69% and a loading capacity of 6.2% ± 0.06%. A phase solubility diagram indicated an increased water solubility of 1 as a function of dendrimer concentration at pH 4.0 and 7.2. In vitro release of 1 from its dendrimer complex indicated high percentage release at pH 4.0. The stability study of the TMScu-dendrimer at 0, 27 and 40 °C showed the formulations to be stable when stored in cool and dark conditions compared to those stored in light and warmer temperatures. Overall, PAMAM dendrimer-G4 is capable of encapsulating 1, increasing its solubility and thus could enhance its bioactivity.

  1. Solid-Phase Immunoassay of Polystyrene-Encapsulated Semiconductor Coreshells for Cardiac Marker Detection

    Directory of Open Access Journals (Sweden)

    Sanghee Kim

    2012-01-01

    Full Text Available A solid-phase immunoassay of polystyrene-encapsulated semiconductor nanoparticles was demonstrated for cardiac troponin I (cTnI detection. CdSe/ZnS coreshells were encapsulated with a carboxyl-functionalized polystyrene nanoparticle to capture the target antibody through a covalent bonding and to eliminate the photoblinking and toxicity of semiconductor luminescent immunosensor. The polystyrene-encapsulated CdSe/ZnS fluorophores on surface-modified glass chip identified cTnI antigens at the level of ~ng/mL. It was an initial demonstration of diagnostic chip for monitoring a cardiovascular disease.

  2. Synthesis and characterization of aba-type copolymers for encapsulation of bovine hemoglobin

    International Nuclear Information System (INIS)

    Lima, Felipe F.; Andrade, Cristina T.

    2012-01-01

    The use of biopolymers for the development of oxygen carriers has been extensively investigated. In this work, three different ABA triblock copolymers were synthesized and used to encapsulate purified bovine hemoglobin, using a double emulsion technique. The effect of polymer composition, homogenization velocity, and addition of a surfactant, on the protein entrapment was evaluated. These copolymers, which have a hydrophilic block, achieved higher values of encapsulation efficiency than the corresponding homopolymers. The increase in homogenization strength also promoted an increase in encapsulation efficiency. Capsules formation occurred even in the absence of PVA. (author)

  3. Use of integrin-linked kinase to extend function of encapsulated pancreatic tissue

    International Nuclear Information System (INIS)

    Blanchette, James O; Langer, Steven J; Leinwand, Leslie L; Sahai, Suchit; Topiwala, Pritesh S; Anseth, Kristi S

    2010-01-01

    We have studied the impact of overexpression of an intracellular signaling protein, integrin-linked kinase (ILK), on the survival and function of encapsulated islet tissue used for the treatment of type 1 diabetes. The dimensions of the encapsulated tissue can impact the stresses placed on the tissue and ILK overexpression shows the ability to extend function of dissociated cells as well as intact islets. These results suggest that lost cell-extracellular matrix interactions in cell encapsulation systems can lead to decreased insulin secretion and ILK signaling is a target to overcome this phenomenon. (communication)

  4. Use of integrin-linked kinase to extend function of encapsulated pancreatic tissue

    Energy Technology Data Exchange (ETDEWEB)

    Blanchette, James O [Department of Chemical Engineering, University of South Carolina, Columbia, SC (United States); Langer, Steven J; Leinwand, Leslie L [Department of Molecular, Cellular and Developmental Biology, University of Colorado, Boulder, CO (United States); Sahai, Suchit; Topiwala, Pritesh S [Biomedical Engineering Program, University of South Carolina, Columbia, SC (United States); Anseth, Kristi S, E-mail: blanchej@cec.sc.ed [Howard Hughes Medical Institute, Boulder, CO (United States)

    2010-12-15

    We have studied the impact of overexpression of an intracellular signaling protein, integrin-linked kinase (ILK), on the survival and function of encapsulated islet tissue used for the treatment of type 1 diabetes. The dimensions of the encapsulated tissue can impact the stresses placed on the tissue and ILK overexpression shows the ability to extend function of dissociated cells as well as intact islets. These results suggest that lost cell-extracellular matrix interactions in cell encapsulation systems can lead to decreased insulin secretion and ILK signaling is a target to overcome this phenomenon. (communication)

  5. Thermal and optical performance of encapsulation systems for flat-plate photovoltaic modules

    Science.gov (United States)

    Minning, C. P.; Coakley, J. F.; Perrygo, C. M.; Garcia, A., III; Cuddihy, E. F.

    1981-01-01

    The electrical power output from a photovoltaic module is strongly influenced by the thermal and optical characteristics of the module encapsulation system. Described are the methodology and computer model for performing fast and accurate thermal and optical evaluations of different encapsulation systems. The computer model is used to evaluate cell temperature, solar energy transmittance through the encapsulation system, and electric power output for operation in a terrestrial environment. Extensive results are presented for both superstrate-module and substrate-module design schemes which include different types of silicon cell materials, pottants, and antireflection coatings.

  6. Device for encapsulating radioactive materials

    International Nuclear Information System (INIS)

    Suthanthiran, K.

    1994-01-01

    A capsule for encapsulating radioactive material for radiation treatment comprising two or more interfitting sleeves, wherein each sleeve comprises a closed bottom portion having a circumferential wall extending therefrom, and an open end located opposite the bottom portion. The sleeves are constructed to fit over one another to thereby establish an effectively sealed capsule container. 3 figs

  7. Ethylene Control Technologies in Extending Postharvest Shelf Life of Climacteric Fruit.

    Science.gov (United States)

    Zhang, Junhua; Cheng, Dong; Wang, Baobin; Khan, Iqbal; Ni, Yonghao

    2017-08-30

    Fresh fruit is important for a healthy diet. However, because of their seasonal production, regional specific cultivation, and perishable nature, it is essential to develop preservation technologies to extend the postharvest shelf life of fresh fruits. Climacteric fruit adopt spoilage because of ethylene, a key hormone associated with the ripening process. Therefore, controlling ethylene activity by following safe and effective approaches is a key to extend the postharvest shelf life of fruit. In this review, ethylene control technologies will be discussed aiming for the need of developing more innovative and effective approaches. The biosynthesis pathway will be given first. Then, the technologies determining the postharvest shelf life of climacteric fruit will be described with special attention to the latest and significant published works in this field. Special attention is given to 1-methylcyclopropene (1-MCP), which is effective in fruit preservation technologies. Finally, the encapsulation technology to improve the stability of 1-MCP will be proposed, using a potential encapsulation agent of 1-MCP, calixarene.

  8. Liposome encapsulation of fluorescent nanoparticles: Quantum dots and silica nanoparticles

    International Nuclear Information System (INIS)

    Chen, C.-S.; Yao Jie; Durst, Richard A.

    2006-01-01

    Quantum dots (QDs) and silica nanoparticles (SNs) are relatively new classes of fluorescent probes that overcome the limitations encountered by organic fluorophores in bioassay and biological imaging applications. We encapsulated QDs and SNs in liposomes and separated nanoparticle-loaded liposomes from unencapsulated nanoparticles by size exclusion chromatography. Fluorescence correlation spectroscopy was used to measure the average number of nanoparticles inside each liposome. Results indicated that nanoparticle-loaded liposomes were formed and separated from unencapsulated nanoparticles by using a Sepharose gel. As expected, fluorescence self-quenching of nanoparticles inside liposomes was not observed. Each liposome encapsulated an average of three QDs. These studies demonstrated that nanoparticles could be successfully encapsulated into liposomes and provided a methodology to quantify the number of nanoparticles inside each liposome by fluorescence correlation spectroscopy

  9. Gravity Probe B Encapsulated

    Science.gov (United States)

    2004-01-01

    In this photo, the Gravity Probe B (GP-B) space vehicle is being encapsulated atop the Delta II launch vehicle. The GP-B is the relativity experiment developed at Stanford University to test two extraordinary predictions of Albert Einstein's general theory of relativity. The experiment will measure, very precisely, the expected tiny changes in the direction of the spin axes of four gyroscopes contained in an Earth-orbiting satellite at a 400-mile altitude. So free are the gyroscopes from disturbance that they will provide an almost perfect space-time reference system. They will measure how space and time are very slightly warped by the presence of the Earth, and, more profoundly, how the Earth's rotation very slightly drags space-time around with it. These effects, though small for the Earth, have far-reaching implications for the nature of matter and the structure of the Universe. GP-B is among the most thoroughly researched programs ever undertaken by NASA. This is the story of a scientific quest in which physicists and engineers have collaborated closely over many years. Inspired by their quest, they have invented a whole range of technologies that are already enlivening other branches of science and engineering. Launched April 20, 2004 , the GP-B program was managed for NASA by the Marshall Space Flight Center. Development of the GP-B is the responsibility of Stanford University along with major subcontractor Lockheed Martin Corporation. (Image credit to Russ Underwood, Lockheed Martin Corporation).

  10. Nutritional value of micro-encapsulated fish oils in rats

    DEFF Research Database (Denmark)

    Rosenquist, Annemette; Hølmer, Gunhild Kofoed

    1996-01-01

    The nutritional value of a micro-encapsulated fish oil product has been investigated. Three groups of 10 male Wistar rats each were fed dietscontaining 20% (w/w) of fat, and only the type and form of the fat added was different. In the test groups 5% (w/w) of fish oil either as such or in amicro......-encapsulated form was incorporated in the diets. The remaining fat was lard supplemented with corn oil to a dietary content of linoleic acid at10% (w/w). The control group received lard and corn oil only. A mixture similar to the dry matter in the micro-encapsulated product was alsoadded to the diets not containing...... this product. The uptake of marine (n-3) polyunsaturated fatty acids (PUFA) from both types of fish oil supplementwas reflected in the fatty acid profiles of liver phosphatidyl cholines (PC), phosphatidyl ethanolamines (PE), triglycerides (TG) and cardiolipin (CL).A suppression of the elongation of linoleic...

  11. Polymeric nanoparticles encapsulating white tea extract for nutraceutical application.

    Science.gov (United States)

    Sanna, Vanna; Lubinu, Giuseppe; Madau, Pierluigi; Pala, Nicolino; Nurra, Salvatore; Mariani, Alberto; Sechi, Mario

    2015-02-25

    With the aim to obtain controlled release and to preserve the antioxidant activity of the polyphenols, nanoencapsulation of white tea extract into polymeric nanoparticles (NPs) based on poly(ε-caprolactone) (PCL) and alginate was successfully performed. NPs were prepared by nanoprecipitation method and were characterized in terms of morphology and chemical properties. Total polyphenols and catechins contents before and after encapsulation were determined. Moreover, in vitro release profiles of encapsulated polyphenols from NPs were investigated in simulated gastrointestinal fluids. The antioxidant activity and stability of encapsulated extract were further evaluated. Interestingly, NPs released 20% of the polyphenols in simulated gastric medium, and 80% after 5 h at pH 7.4, showing a good capacity to control the polyphenols delivery. Furthermore, DPPH(•) assay confirmed that white tea extract retained its antioxidant activity and NPs protected tea polyphenols from degradation, thus opening new perspectives for the exploitation of white tea extract-loaded NPs for nutraceutical applications.

  12. Sputtered Encapsulation as Wafer Level Packaging for Isolatable MEMS Devices: A Technique Demonstrated on a Capacitive Accelerometer

    Directory of Open Access Journals (Sweden)

    Azrul Azlan Hamzah

    2008-11-01

    Full Text Available This paper discusses sputtered silicon encapsulation as a wafer level packaging approach for isolatable MEMS devices. Devices such as accelerometers, RF switches, inductors, and filters that do not require interaction with the surroundings to function, could thus be fully encapsulated at the wafer level after fabrication. A MEMSTech 50g capacitive accelerometer was used to demonstrate a sputtered encapsulation technique. Encapsulation with a very uniform surface profile was achieved using spin-on glass (SOG as a sacrificial layer, SU-8 as base layer, RF sputtered silicon as main structural layer, eutectic gold-silicon as seal layer, and liquid crystal polymer (LCP as outer encapsulant layer. SEM inspection and capacitance test indicated that the movable elements were released after encapsulation. Nanoindentation test confirmed that the encapsulated device is sufficiently robust to withstand a transfer molding process. Thus, an encapsulation technique that is robust, CMOS compatible, and economical has been successfully developed for packaging isolatable MEMS devices at the wafer level.

  13. Aerobic TCE degradation by encapsulated toluene-oxidizing bacteria, Pseudomonas putida and Bacillus spp.

    Science.gov (United States)

    Kim, Seungjin; Bae, Wookeun; Hwang, Jungmin; Park, Jaewoo

    2010-01-01

    The degradation rates of toluene and trichloroethylene (TCE) by Pseudomonas putida and Bacillus spp. that were encapsulated in polyethylene glycol (PEG) polymers were evaluated in comparison with the results of exposure to suspended cultures. PEG monomers were polymerized together with TCE-degrading microorganisms, such that the cells were encapsulated in and protected by the matrices of the PEG polymers. TCE concentrations were varied from 0.1 to 1.5 mg/L. In the suspended cultures of P. putida, the TCE removal rate decreased as the initial TCE concentration increased, revealing TCE toxicity or a limitation of reducing power, or both. When the cells were encapsulated, an initial lag period of about 10-20 h was observed for toluene degradation. Once acclimated, the encapsulated P. putida cultures were more tolerant to TCE at an experimental range of 0.6-1.0 mg/L and gave higher transfer efficiencies (mass TCE transformed/mass toluene utilized). When the TCE concentration was low (e.g., 0.1 mg/L) the removal of TCE per unit mass of cells (specific removal) was significantly lower, probably due to a diffusion limitation into the PEG pellet. Encapsulated Bacillus spp. were able to degrade TCE cometabolically. The encapsulated Bacillus spp. gave significantly higher values than did P. putida in the specific removal and the transfer efficiency, particularly at relatively high TCE concentration of approximately 1.0±0.5 mg/L. The transfer efficiency by encapsulated Bacillus spp. in this study was 0.27 mgTCE/mgToluene, which was one to two orders of magnitude greater than the reported values.

  14. Analysis of Double-encapsulated Fuel Rods

    Energy Technology Data Exchange (ETDEWEB)

    Hales, Jason Dean [Idaho National Laboratory; Medvedev, Pavel G [Idaho National Laboratory; Novascone, Stephen Rhead [Idaho National Laboratory; Perez, Danielle Marie [Idaho National Laboratory; Williamson, Richard L [Idaho National Laboratory

    2014-09-01

    In an LWR fuel rod, the cladding encapsulates the fuel, contains fission products, and transfers heat directly to the water coolant. In some situations, it may be advantageous to separate the cladding from the coolant through use of a secondary cladding or capsule. This may be done to increase confidence that the fuel or fission products will not mix with the coolant, to provide a mechanism for controlling the rod temperature, or to place multiple experimental rodlets within a single housing. With an axisymmetric assumption, it is possible to derive closed-form expressions for the temperature profile in a fuel rod using radially-constant thermal conductivity in the fuel. This is true for both a traditional fuel-cladding rod and a double-encapsulated fuel (fuel, cladding, capsule) configuration. Likewise, it is possible to employ a fuel performance code to analyse both a traditional and a double-encapsulated fuel. In the case of the latter, two sets of gap heat transfer conditions must be imposed. In this work, we review the equations associated with radial heat transfer in a cylindrical system, present analytic and computational results for a postulated power and gas mixture history for IFA-744, and describe the analysis of the AFC-2A, 2B metallic fuel alloy experiments at the Advanced Test Reactor, including the effect of a release of fission products into the cladding-capsule gap. The computational results for these two cases were obtained using BISON, a fuel performance code under development at Idaho National Laboratory.

  15. Multiple encapsulation of LANL waste using polymers. Final report

    International Nuclear Information System (INIS)

    Schwartz, R.L.

    1994-01-01

    Polymer encapsulation of lead shielding/blasting grit (surrogate) mixed waste was optimized at bench scale using melamine formaldehyde, polyurethane, and butadiene thermosetting polymers. Three pellet-based intermediate waste forms, and a final waste form, were prepared, each providing an additional level of integrity. Encapsulated waste integrity was measured by chemical and physical techniques. Compliance was established using the Toxicity Characteristic Leaching Procedure. Equipment appropriate to pilot-scale demonstration of program techniques was investigated. A preliminary equipment list and layout, and process block flow diagram were prepared

  16. Sliver Solar Cells: High-Efficiency, Low-Cost PV Technology

    Directory of Open Access Journals (Sweden)

    Evan Franklin

    2007-01-01

    Full Text Available Sliver cells are thin, single-crystal silicon solar cells fabricated using standard fabrication technology. Sliver modules, composed of several thousand individual Sliver cells, can be efficient, low-cost, bifacial, transparent, flexible, shadow tolerant, and lightweight. Compared with current PV technology, mature Sliver technology will need 10% of the pure silicon and fewer than 5% of the wafer starts per MW of factory output. This paper deals with two distinct challenges related to Sliver cell and Sliver module production: providing a mature and robust Sliver cell fabrication method which produces a high yield of highly efficient Sliver cells, and which is suitable for transfer to industry; and, handling, electrically interconnecting, and encapsulating billions of sliver cells at low cost. Sliver cells with efficiencies of 20% have been fabricated at ANU using a reliable, optimised processing sequence, while low-cost encapsulation methods have been demonstrated using a submodule technique.

  17. Plastic Encapsulated Microcircuits (PEMs) Reliability Guide

    Science.gov (United States)

    Sandor, M.

    2000-01-01

    It is reported by some users and has been demonstrated by others via testing and qualification that the quality and reliability of plastic-encapsulated microcircuits (PEMs) manufactured today are excellent in commercial applications and closely equivalent, and in some cases superior to their hemetic counterparts.

  18. Encapsulation of nanoparticles into single-crystal ZnO nanorods and microrods.

    Science.gov (United States)

    Liu, Jinzhang; Notarianni, Marco; Rintoul, Llew; Motta, Nunzio

    2014-01-01

    One-dimensional single crystal incorporating functional nanoparticles of other materials could be an interesting platform for various applications. We studied the encapsulation of nanoparticles into single-crystal ZnO nanorods by exploiting the crystal growth of ZnO in aqueous solution. Two types of nanodiamonds with mean diameters of 10 nm and 40 nm, respectively, and polymer nanobeads with size of 200 nm have been used to study the encapsulation process. It was found that by regrowing these ZnO nanorods with nanoparticles attached to their surfaces, a full encapsulation of nanoparticles into nanorods can be achieved. We demonstrate that our low-temperature aqueous solution growth of ZnO nanorods do not affect or cause degradation of the nanoparticles of either inorganic or organic materials. This new growth method opens the way to a plethora of applications combining the properties of single crystal host and encapsulated nanoparticles. We perform micro-photoluminescence measurement on a single ZnO nanorod containing luminescent nanodiamonds and the spectrum has a different shape from that of naked nanodiamonds, revealing the cavity effect of ZnO nanorod.

  19. Nuclear waste viewed in a new light; a synchrotron study of uranium encapsulated in grout

    Energy Technology Data Exchange (ETDEWEB)

    Stitt, C.A., E-mail: Camilla.stitt@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Hart, M., E-mail: oxford.mike@gmail.com [Diamond Light Source Limited, Harwell Science and Innovation Campus, Fermi Avenue, Didcot, Oxfordshire OX11 0QX (United Kingdom); Harker, N.J., E-mail: nicholas.harker@esrf.fr [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Hallam, K.R., E-mail: k.r.hallam@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); MacFarlane, J., E-mail: james.macfarlane@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Banos, A., E-mail: antonis.banos@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Paraskevoulakos, C., E-mail: cp13846@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom); Butcher, E., E-mail: ed.j.butcher@nnl.co.uk [National Nuclear Laboratory, Seascale, Cumbria CA20 1 PG (United Kingdom); Padovani, C., E-mail: cristiano.padovani@nda.gov.uk [Radioactive Waste Management Limited (formerly the Radioactive Waste Management Directorate of the UK Nuclear Decommissioning Authority), Curie Avenue, Didcot, Oxfordshire OX11 0RH (United Kingdom); Scott, T.B., E-mail: t.b.scott@bristol.ac.uk [Interface Analysis Centre, H. H. Wills Physics Laboratory, University of Bristol, Tyndall Avenue, Bristol BS8 1TL (United Kingdom)

    2015-03-21

    Highlights: • Unirradiated Magnox uranium was encapsulated in grout and exposed to hydrogen. • Synchrotron X-ray tomography imaged the uranium corrosion before and after exposure. • Synchrotron X-ray powder diffraction identified the corrosion products; UH{sub 3} and UO{sub 2}. • Uranium encapsulated in grout oxidised via the anoxic U + H{sub 2}O regime. • Successful in-situ, non-invasive examination of pyrophoric and radioactive material - Abstract: How do you characterise the contents of a sealed nuclear waste package without breaking it open? This question is important when the contained corrosion products are potentially reactive with air and radioactive. Synchrotron X-rays have been used to perform micro-scale in-situ observation and characterisation of uranium encapsulated in grout; a simulation for a typical intermediate level waste storage packet. X-ray tomography and X-ray powder diffraction generated both qualitative and quantitative data from a grout-encapsulated uranium sample before, and after, deliberately constrained H{sub 2} corrosion. Tomographic reconstructions provided a means of assessing the extent, rates and character of the corrosion reactions by comparing the relative densities between the materials and the volume of reaction products. The oxidation of uranium in grout was found to follow the anoxic U + H{sub 2}O oxidation regime, and the pore network within the grout was observed to influence the growth of uranium hydride sites across the metal surface. Powder diffraction analysis identified the corrosion products as UO{sub 2} and UH{sub 3}, and permitted measurement of corrosion-induced strain. Together, X-ray tomography and diffraction provide means of accurately determining the types and extent of uranium corrosion occurring, thereby offering a future tool for isolating and studying the reactions occurring in real full-scale waste package systems.

  20. Modulation of Rat Cecal Microbiota by Administration of Raffinose and Encapsulated Bifidobacterium breve

    OpenAIRE

    Dinoto, Achmad; Suksomcheep, Akarat; Ishizuka, Satoshi; Kimura, Hanae; Hanada, Satoshi; Kamagata, Yoichi; Asano, Kozo; Tomita, Fusao; Yokota, Atsushi

    2006-01-01

    To investigate the effects of administration of raffinose and encapsulated Bifidobacterium breve JCM 1192T cells on the rat cecal microbiota, in a preclinical synbiotic study groups of male WKAH/Hkm Slc rats were fed for 3 weeks with four different test diets: basal diet (group BD), basal diet supplemented with raffinose (group RAF), basal diet supplemented with encapsulated B. breve (group CB), and basal diet supplemented with both raffinose and encapsulated B. breve (group RCB). The bacteri...

  1. Encapsulation of aluminium in geopolymers produced from metakaolin

    Energy Technology Data Exchange (ETDEWEB)

    Kuenzel, C. [Department of Civil and Environmental Engineering, Imperial College London (United Kingdom); Centre for Advanced Structural Ceramics, Department of Materials, Imperial College London (United Kingdom); Neville, T.P. [Centre for CO_2 Technology, Department of Chemical Engineering, University College London (United Kingdom); Omakowski, T. [Flowcrete, Group Ltd., Cheshire (United Kingdom); Vandeperre, L. [Centre for Advanced Structural Ceramics, Department of Materials, Imperial College London (United Kingdom); Boccaccini, A.R. [Institute of Biomaterials, University of Erlangen-Nuremberg (Germany); Bensted, J.; Simons, S.J.R. [Centre for CO_2 Technology, Department of Chemical Engineering, University College London (United Kingdom); Cheeseman, C.R., E-mail: c.cheeseman@imperial.ac.uk [Department of Civil and Environmental Engineering, Imperial College London (United Kingdom)

    2014-04-01

    Magnox swarf contaminated with trace levels of Al metal is an important UK legacy waste originated from the fuel rod cladding system used in Magnox nuclear power stations. Composite cements made from Portland cement and blast furnace slag form a potential encapsulation matrix. However the high pH of this system causes the Al metal to corrode causing durability issues. Geopolymers derived from metakaolin are being investigated as an alternative encapsulation matrix for Magnox swarf waste and the corrosion kinetics and surface interactions of Al with metakaolin geopolymer are reported in this paper. It is shown that the pH of the geopolymer paste can be controlled by the selection of metakaolin and the sodium silicate solution used to form the geopolymer. A decrease in pH of the activation solution reduces corrosion of the Al metal and increases the stability of bayerite and gibbsite layers formed on the Al surface. The bayerite and gibbsite act as a passivation layer which inhibits further corrosion and mitigates H{sub 2} generation. The research shows that optimised metakaolin geopolymers have potential to be used to encapsulate legacy Magnox swarf wastes.

  2. Cyclic water-trimer encapsulation into D2 (22)-C84 fullerene

    Science.gov (United States)

    Slanina, Zdeněk; Uhlík, Filip; Nagase, Shigeru; Akasaka, Takeshi; Lu, Xing; Adamowicz, Ludwik

    2018-03-01

    The cyclic water-trimer encapsulations into D2 (22)-C84 fullerene are evaluated. The encapsulation energy is computed at the M06-2X/6-31++G∗∗ level and it is found that the trimer storage in C84 yields the potential-energy gain of 10.4 kcal/mol. The encapsulated trimer can have two different forms, either the conformation known with the free gas-phase water trimer or the arrangement with the three non-hydrogen bonded H atoms on the same side of the O-O-O plane. The latter endohedral isomer is lower in the potential energy by 0.071 kcal/mol and forms about 57% of their equilibrium mixture at room temperature.

  3. Development of Hollow Steel Ball Macro-Encapsulated PCM for Thermal Energy Storage Concrete

    Directory of Open Access Journals (Sweden)

    Zhijun Dong

    2016-01-01

    Full Text Available The application of thermal energy storage with phase change materials (PCMs for energy efficiency of buildings grew rapidly in the last few years. In this research, octadecane paraffin was served as a PCM, and a structural concrete with the function of indoor temperature control was developed by using a macro-encapsulated PCM hollow steel ball (HSB. The macro-encapsulated PCM-HSB was prepared by incorporation of octadecane into HSBs through vacuum impregnation. Test results showed that the maximum percentage of octadecane carried by HSBs was 80.3% by mass. The macro-encapsulated PCM-HSB has a latent heat storage capacity as high as 200.5 J/g. The compressive strength of concrete with macro-encapsulated PCM-HSB at 28 days ranged from 22 to 40 MPa. The indoor thermal performance test revealed that concrete with macro-encapsulated octadecane-HSB was capable of reducing the peak indoor air temperature and the fluctuation of indoor temperature. It can be very effective in transferring the heating and cooling loads away from the peak demand times.

  4. Development of Hollow Steel Ball Macro-Encapsulated PCM for Thermal Energy Storage Concrete.

    Science.gov (United States)

    Dong, Zhijun; Cui, Hongzhi; Tang, Waiching; Chen, Dazhu; Wen, Haibo

    2016-01-19

    The application of thermal energy storage with phase change materials (PCMs) for energy efficiency of buildings grew rapidly in the last few years. In this research, octadecane paraffin was served as a PCM, and a structural concrete with the function of indoor temperature control was developed by using a macro-encapsulated PCM hollow steel ball (HSB). The macro-encapsulated PCM-HSB was prepared by incorporation of octadecane into HSBs through vacuum impregnation. Test results showed that the maximum percentage of octadecane carried by HSBs was 80.3% by mass. The macro-encapsulated PCM-HSB has a latent heat storage capacity as high as 200.5 J/g. The compressive strength of concrete with macro-encapsulated PCM-HSB at 28 days ranged from 22 to 40 MPa. The indoor thermal performance test revealed that concrete with macro-encapsulated octadecane-HSB was capable of reducing the peak indoor air temperature and the fluctuation of indoor temperature. It can be very effective in transferring the heating and cooling loads away from the peak demand times.

  5. Development of Hollow Steel Ball Macro-Encapsulated PCM for Thermal Energy Storage Concrete

    Science.gov (United States)

    Dong, Zhijun; Cui, Hongzhi; Tang, Waiching; Chen, Dazhu; Wen, Haibo

    2016-01-01

    The application of thermal energy storage with phase change materials (PCMs) for energy efficiency of buildings grew rapidly in the last few years. In this research, octadecane paraffin was served as a PCM, and a structural concrete with the function of indoor temperature control was developed by using a macro-encapsulated PCM hollow steel ball (HSB). The macro-encapsulated PCM-HSB was prepared by incorporation of octadecane into HSBs through vacuum impregnation. Test results showed that the maximum percentage of octadecane carried by HSBs was 80.3% by mass. The macro-encapsulated PCM-HSB has a latent heat storage capacity as high as 200.5 J/g. The compressive strength of concrete with macro-encapsulated PCM-HSB at 28 days ranged from 22 to 40 MPa. The indoor thermal performance test revealed that concrete with macro-encapsulated octadecane-HSB was capable of reducing the peak indoor air temperature and the fluctuation of indoor temperature. It can be very effective in transferring the heating and cooling loads away from the peak demand times. PMID:28787859

  6. Accelerated/abbreviated test methods of the low-cost silicon solar array project. Study 4, task 3: Encapsulation

    Science.gov (United States)

    Kolyer, J. M.; Mann, N. R.

    1977-01-01

    Methods of accelerated and abbreviated testing were developed and applied to solar cell encapsulants. These encapsulants must provide protection for as long as 20 years outdoors at different locations within the United States. Consequently, encapsulants were exposed for increasing periods of time to the inherent climatic variables of temperature, humidity, and solar flux. Property changes in the encapsulants were observed. The goal was to predict long term behavior of encapsulants based upon experimental data obtained over relatively short test periods.

  7. Evaluation of antinociceptive activity of nanoliposome-encapsulated and free-form diclofenac in rats and mice.

    Science.gov (United States)

    Goh, Jun Zheng; Tang, Sook Nai; Chiong, Hoe Siong; Yong, Yoke Keong; Zuraini, Ahmad; Hakim, Muhammad Nazrul

    2015-01-01

    Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID) that exhibits anti-inflammatory, antinociceptive, and antipyretic activities. Liposomes have been shown to improve the therapeutic efficacy of encapsulated drugs. The present study was conducted to compare the antinociceptive properties between liposome-encapsulated and free-form diclofenac in vivo via different nociceptive assay models. Liposome-encapsulated diclofenac was prepared using the commercialized proliposome method. Antinociceptive effects of liposome-encapsulated and free-form diclofenac were evaluated using formalin test, acetic acid-induced abdominal writhing test, Randall-Selitto paw pressure test, and plantar test. The results of the writhing test showed a significant reduction of abdominal constriction in all treatment groups in a dose-dependent manner. The 20 mg/kg liposome-encapsulated diclofenac demonstrated the highest antinociceptive effect at 78.97% compared with 55.89% in the free-form group at equivalent dosage. Both liposome-encapsulated and free-form diclofenac produced significant results in the late phase of formalin assay at a dose of 20 mg/kg, with antinociception percentages of 78.84% and 60.71%, respectively. Significant results of antinociception were also observed in both hyperalgesia assays. For Randall-Sellito assay, the highest antinociception effect of 71.38% was achieved with 20 mg/kg liposome-encapsulated diclofenac, while the lowest antinociceptive effect of 17.32% was recorded with 0 mg/kg liposome formulation, whereas in the plantar test, the highest antinociceptive effect was achieved at 56.7% with 20 mg/kg liposome-encapsulated diclofenac, and the lowest effect was shown with 0 mg/kg liposome formulation of 8.89%. The present study suggests that liposome-encapsulated diclofenac exhibits higher antinociceptive efficacy in a dose-dependent manner in comparison with free-form diclofenac.

  8. Wax encapsulation of water-soluble compounds for application in foods.

    Science.gov (United States)

    Mellema, M; Van Benthum, W A J; Boer, B; Von Harras, J; Visser, A

    2006-11-01

    Water-soluble ingredients have been successfully encapsulated in wax using two preparation techniques. The first technique ('solid preparation') leads to relatively large wax particles. The second technique ('liquid preparation') leads to relatively small wax particles immersed in vegetable oil. On the first technique: stable encapsulation of water-soluble colourants (dissolved at low concentration in water) has been achieved making use of beeswax and PGPR. The leakage from the capsules, for instance of size 2 mm, is about 30% after 16 weeks storage in water at room temperature. To form such capsules a minimum wax mass of 40% relative to the total mass is needed. High amounts of salt or acids at the inside water phase causes more leaking, probably because of the osmotic pressure difference. Osmotic matching of inner and outer phase can lead to a dramatic reduction in leakage. Fat capsules are less suitable to incorporate water soluble colourants. The reason for this could be a difference in crystal structure (fat is less ductile and more brittle). On the second technique: stable encapsulation of water-soluble colourants (encapsulated in solid wax particles) has been achieved making use of carnauba wax. The leakage from the capsules, for instance of size 250 mm, is about 40% after 1 weeks storage in water at room temperature.

  9. Preparation and anti-cancer activity of polymer-encapsulated curcumin nanoparticles

    International Nuclear Information System (INIS)

    Ha, Phuong Thu; Tran, Dai Lam; Nguyen, Xuan Phuc; Le, Mai Huong; Ha Tran, Thi Hong; Hoang, Thi My Nhung; Huong Le, Thi Thu; Duong, Tuan Quang

    2012-01-01

    Curcumin (Cur) is a yellow compound isolated from rhizome of the herb curcuma longa. Curcumin possesses antioxidant, anti-inflammatory, anti-carcinogenic and antimicrobial properties, and suppresses proliferation of many tumor cells. However, the clinical application of curcumin in cancer treatment is considerably limited due to its serious poor delivery characteristics. In order to increase the hydrophilicity and drug delivery capability, we encapsulated curcumin into copolymer PLA-TPGS, 1,3-beta-glucan (Glu), O-carboxymethyl chitosan (OCMCs) and folate-conjugated OCMCs (OCMCs-Fol). These polymer-encapsulated curcumin nanoparticles (Cur-PLA-TPGS, Cur-Glu, Cur-OCMCs and Cur-OCMCs-Fol) were characterized by infrared (IR), fluorescence (FL), photoluminescence (PL) spectra, field emission scanning electron microscopy (FE-SEM), and found to be spherical particles with an average size of 50–100 nm, being suitable for drug delivery applications. They were much more soluble in water than not only free curcumin but also other biodegradable polymer-encapsulated curcumin nanoparticles. The anti-tumor promoting assay was carried out, showing the positive effects of Cur-Glu and Cur-PLA-TPGS on tumor promotion of Hep-G2 cell line in vitro. Confocal microscopy revealed that the nano-sized curcumin encapsulated by polymers OCMCs and OCMCs-Fol significantly enhanced the cellular uptake (cancer cell HT29 and HeLa). (paper)

  10. Preparation of keratin-based microcapsules for encapsulation of hydrophilic molecules.

    Science.gov (United States)

    Rajabinejad, Hossein; Patrucco, Alessia; Caringella, Rosalinda; Montarsolo, Alessio; Zoccola, Marina; Pozzo, Pier Davide

    2018-01-01

    The interest towards microcapsules based on non-toxic, biodegradable and biocompatible polymers, such as proteins, is increasing considerably. In this work, microcapsules were prepared using water soluble keratin, known as keratoses, with the aim of encapsulating hydrophilic molecules. Keratoses were obtained via oxidizing extraction of pristine wool, previously degreased by Soxhlet. In order to better understand the shell part of microcapsules, pristine wool and obtained keratoses were investigated by FT-IR, gel-electrophoresis and HPLC. Production of the microcapsules was carried out by a sonication method. Thermal properties of microcapsules were investigated by DSC. Microencapsulation and dye encapsulation yields were obtained by UV-spectroscopy. Morphological structure of microcapsules was studied by light microscopy, SEM, and AFM. The molecular weights of proteins analyzed using gel-electrophoresis resulted in the range of 38-62kDa. The results confirmed that the hydrophilic dye (Telon Blue) was introduced inside the keratoses shells by sonication and the final microcapsules diameter ranged from 0.5 to 4µm. Light microscope investigation evidenced the presence of the dye inside the keratoses vesicles, confirming their capability of encapsulating hydrophilic molecules. The microcapsule yield and dye encapsulation yield were found to be 28.87±3% and 83.62±5% respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Preparation and anti-cancer activity of polymer-encapsulated curcumin nanoparticles

    Science.gov (United States)

    Thu Ha, Phuong; Huong Le, Mai; Nhung Hoang, Thi My; Thu Huong Le, Thi; Quang Duong, Tuan; Tran, Thi Hong Ha; Tran, Dai Lam; Phuc Nguyen, Xuan

    2012-09-01

    Curcumin (Cur) is a yellow compound isolated from rhizome of the herb curcuma longa. Curcumin possesses antioxidant, anti-inflammatory, anti-carcinogenic and antimicrobial properties, and suppresses proliferation of many tumor cells. However, the clinical application of curcumin in cancer treatment is considerably limited due to its serious poor delivery characteristics. In order to increase the hydrophilicity and drug delivery capability, we encapsulated curcumin into copolymer PLA-TPGS, 1,3-beta-glucan (Glu), O-carboxymethyl chitosan (OCMCs) and folate-conjugated OCMCs (OCMCs-Fol). These polymer-encapsulated curcumin nanoparticles (Cur-PLA-TPGS, Cur-Glu, Cur-OCMCs and Cur-OCMCs-Fol) were characterized by infrared (IR), fluorescence (FL), photoluminescence (PL) spectra, field emission scanning electron microscopy (FE-SEM), and found to be spherical particles with an average size of 50-100 nm, being suitable for drug delivery applications. They were much more soluble in water than not only free curcumin but also other biodegradable polymer-encapsulated curcumin nanoparticles. The anti-tumor promoting assay was carried out, showing the positive effects of Cur-Glu and Cur-PLA-TPGS on tumor promotion of Hep-G2 cell line in vitro. Confocal microscopy revealed that the nano-sized curcumin encapsulated by polymers OCMCs and OCMCs-Fol significantly enhanced the cellular uptake (cancer cell HT29 and HeLa).

  12. Novel encapsulation technique for incorporation of high permittivity fillers into silicone elastomers

    DEFF Research Database (Denmark)

    Mazurek, Piotr Stanislaw; Hvilsted, Søren; Skov, Anne Ladegaard

    2014-01-01

    permittivity fillers, 2) Grafting of high permittivity molecules onto the polymer backbone in the elastomer, and 3) Encapsulation of high permittivity fillers. The approach investigated here is a new type of encapsulation which does not interfere with the mechanical properties to the same content...

  13. Neutron Characterization of Encapsulated ATF-1/LANL-1 Mockup Fuel Capsules

    Energy Technology Data Exchange (ETDEWEB)

    Vogel, Sven C. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Borges, Nicholas Paul [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Losko, Adrian Simon [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mosby, Shea Morgan [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Voit, Stewart Lancaster [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); White, Joshua Taylor [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Byler, Darrin David [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Dunwoody, John Tyler [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Nelson, Andrew Thomas [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Mcclellan, Kenneth James [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2017-09-28

    Twenty pellets of mock-up accident tolerant fuels UN-U3Si5 were produced at LANL and loaded in two rodlet/capsule assemblies. Tomographic imaging and diffraction measurements were performed to characterize these samples at the Flight-Path 5 and HIPPO beam lines at LANSCE/LANL between November 2016 and January 2017 as well as in August 2017. The entire ~10 cm long, ~1 cm diameter fuel volume could be characterized, however due to time constraints only 2 mm slices in 4mm increments were characterized with neutron diffraction and a 28mm subset of the entire sample was characterized with energy-resolved neutron imaging. The double encapsulation of the fuel into two steel containers does not pose a problem for the neutron analysis and the methods could be applied to enriched as well irradiated fuels.

  14. Osmotic pressure-dependent release profiles of payloads from nanocontainers by co-encapsulation of simple salts

    Science.gov (United States)

    Behzadi, Shahed; Rosenauer, Christine; Kappl, Michael; Mohr, Kristin; Landfester, Katharina; Crespy, Daniel

    2016-06-01

    The encapsulation of payloads in micro- to nano-scale capsules allows protection of the payload from the surrounding environment and control of its release profile. Herein, we program the release of hydrophilic payloads from nanocontainers by co-encapsulating simple inorganic salts for adjusting the osmotic pressure. The latter either leads to a burst release at high concentrations of co-encapsulated salts or a sustained release at lower concentrations. Osmotic pressure causes swelling of the nanocapsule's shell and therefore sustained release profiles can be adjusted by crosslinking it. The approach presented allows for programing the release of payloads by co-encapsulating inexpensive salts inside nanocontainers without the help of stimuli-responsive materials.The encapsulation of payloads in micro- to nano-scale capsules allows protection of the payload from the surrounding environment and control of its release profile. Herein, we program the release of hydrophilic payloads from nanocontainers by co-encapsulating simple inorganic salts for adjusting the osmotic pressure. The latter either leads to a burst release at high concentrations of co-encapsulated salts or a sustained release at lower concentrations. Osmotic pressure causes swelling of the nanocapsule's shell and therefore sustained release profiles can be adjusted by crosslinking it. The approach presented allows for programing the release of payloads by co-encapsulating inexpensive salts inside nanocontainers without the help of stimuli-responsive materials. Electronic supplementary information (ESI) available. See DOI: 10.1039/c6nr01882c

  15. Anisotropic silica mesostructures for DNA encapsulation

    Indian Academy of Sciences (India)

    The encapsulation of biomolecules in inert meso or nanostructures is an important step towards controlling drug delivery agents. Mesoporous silica nanoparticles (MSN) are of immense importance owing to their high surface area, large pore size, uniform particle size and chemical inertness. Reverse micellar method with ...

  16. Amidase encapsulated O-carboxymethyl chitosan nanoparticles for vaccine delivery.

    Science.gov (United States)

    Smitha, K T; Sreelakshmi, M; Nisha, N; Jayakumar, R; Biswas, Raja

    2014-02-01

    This work reports the development of amidase encapsulated O-carboxymethyl chitosan nanoparticles (Ami-O-CMC NPs) of 300±50 nm size by ionic cross-linking method. The prepared Ami-O-CMC NPs had an encapsulation efficiency of 55.39%. Haemolysis assay and cytotoxicity studies proved the hemocompatibility and cytocompatibility of the prepared NPs. The sustained release of Ami from the NPs is expected to prolong its immunogenicity and in turn lead to development of better protective immunity against Staphylococcus aureus infections. Copyright © 2013 Elsevier B.V. All rights reserved.

  17. Oxidation of free and encapsulated oil fractions in dried microencapsulated fish oils

    Directory of Open Access Journals (Sweden)

    Márquez-Ruiz, G.

    2000-12-01

    Full Text Available The objective of this work was to evaluate oxidation of dried microencapsulated fish oils (DMFO during storage at ambient temperature, and to examine the influence of oils distribution (free vs. encapsulated oil in these complex lipidic systems. DMF0 were prepared by freeze-drying emulsions containing sodium caseinate, lactose and fish oil, with and without adding the antioxidant mixture ALT (ascorbic acid, lecithin and tocopherol. Samples were stored at 25 or 30ºC either in the dark or light with limited, accesible air or under vacuum. The progress of oxidation was followed through quantitation of triglyceride polymers, and oxidation levels of free and encapsulated oil fractions were differentiated. Results showed that oxidation was very rapid both in free and encapsulated oil fractions in all DMFOs exposed to light. In the dark, oxidation was triggered first in the free oil fraction of samples not protected with ALT but, in contrast, samples with ALT showed significantly higher oxidation levels in encapsulated than in free oil fractions, regardless of the limited or free availability of air. These results indicated that addition of the antioxidant system ALT was more effective in the free oil fraction, thus reflecting the great influence of partitioning and/or orientation of antioxidants on their efficacy in complex lipid systems.El objetivo de este trabajo es la evaluación de la oxidación de aceites de pescado microencapsulados en matriz seca (DMFO durante su almacenamiento a temperatura ambiente, y examinar la influencia de la distribución del aceite (aceite libre frente a aceite encapsulado en estos sistemas lipídicos complejos. Las muestras se prepararon mediante liofilización de emulsiones constituidas por caseinato sódico, lactosa y aceite de pescado, con o sin la mezcla antioxidante ALT (ácido ascórbico, lecitina y tocoferol; y se almacenaron a 25 o 30ºC a la luz o a la oscuridad, con aire limitado, accesible o al vac

  18. Retention of gene expression in porcine islets after agarose encapsulation and long-term culture

    International Nuclear Information System (INIS)

    Dumpala, Pradeep R.; Holdcraft, Robert W.; Martis, Prithy C.; Laramore, Melissa A.; Parker, Thomas S.; Levine, Daniel M.; Smith, Barry H.; Gazda, Lawrence S.

    2016-01-01

    Agarose encapsulation of porcine islets allows extended in vitro culture, providing ample time to determine the functional capacity of the islets and conduct comprehensive microbiological safety testing prior to implantation as a treatment for type 1 diabetes mellitus. However, the effect that agarose encapsulation and long-term culture may have on porcine islet gene expression is unknown. The aim of the present study was to compare the transcriptome of encapsulated porcine islets following long-term in vitro culture against free islets cultured overnight. Global gene expression analysis revealed no significant change in the expression of 98.47% of genes. This indicates that the gene expression profile of free islets is highly conserved following encapsulation and long-term culture. Importantly, the expression levels of genes that code for critical hormones secreted by islets (insulin, glucagon, and somatostatin) as well as transcripts encoding proteins involved in their packaging and secretion are unchanged. While a small number of genes known to play roles in the insulin secretion and insulin signaling pathways are differentially expressed, our results show that overall gene expression is retained following islet isolation, agarose encapsulation, and long-term culture. - Highlights: • Effect of agarose encapsulation and 8 week culture on porcine islets was analyzed. • Transcriptome analysis revealed no significant change in a majority (98%) of genes. • Agarose encapsulation allows for long-term culture of porcine islets. • Islet culture allows for functional and microbial testing prior to clinical use.

  19. Retention of gene expression in porcine islets after agarose encapsulation and long-term culture

    Energy Technology Data Exchange (ETDEWEB)

    Dumpala, Pradeep R., E-mail: pdumpala@rixd.org [The Rogosin Institute – Xenia Division, 740 Birch Road, Xenia, OH 45385 (United States); Holdcraft, Robert W.; Martis, Prithy C.; Laramore, Melissa A. [The Rogosin Institute – Xenia Division, 740 Birch Road, Xenia, OH 45385 (United States); Parker, Thomas S.; Levine, Daniel M. [The Rogosin Institute, 505 East 70th Street, New York, NY 10021 (United States); Smith, Barry H. [The Rogosin Institute, 505 East 70th Street, New York, NY 10021 (United States); NewYork-Presbyterian Hospital, Weill Medical College of Cornell University, 1300 York Avenue, New York, NY 10021 (United States); Gazda, Lawrence S. [The Rogosin Institute – Xenia Division, 740 Birch Road, Xenia, OH 45385 (United States)

    2016-08-05

    Agarose encapsulation of porcine islets allows extended in vitro culture, providing ample time to determine the functional capacity of the islets and conduct comprehensive microbiological safety testing prior to implantation as a treatment for type 1 diabetes mellitus. However, the effect that agarose encapsulation and long-term culture may have on porcine islet gene expression is unknown. The aim of the present study was to compare the transcriptome of encapsulated porcine islets following long-term in vitro culture against free islets cultured overnight. Global gene expression analysis revealed no significant change in the expression of 98.47% of genes. This indicates that the gene expression profile of free islets is highly conserved following encapsulation and long-term culture. Importantly, the expression levels of genes that code for critical hormones secreted by islets (insulin, glucagon, and somatostatin) as well as transcripts encoding proteins involved in their packaging and secretion are unchanged. While a small number of genes known to play roles in the insulin secretion and insulin signaling pathways are differentially expressed, our results show that overall gene expression is retained following islet isolation, agarose encapsulation, and long-term culture. - Highlights: • Effect of agarose encapsulation and 8 week culture on porcine islets was analyzed. • Transcriptome analysis revealed no significant change in a majority (98%) of genes. • Agarose encapsulation allows for long-term culture of porcine islets. • Islet culture allows for functional and microbial testing prior to clinical use.

  20. Synthesis carbon-encapsulated NiZn ferrite nanocomposites by in-situ starch coating route combined with hydrogen thermal reduction

    Energy Technology Data Exchange (ETDEWEB)

    Liu, Fuming [Department of Materials Chemistry, Nanchang Hangkong University, Nanchang 330063 (China); Xie, Yu, E-mail: xieyu_121@163.com [Department of Materials Chemistry, Nanchang Hangkong University, Nanchang 330063 (China); Key Laboratory of Photochemical Conversion and Optoelectronic Materials, TIPC, Chinese Academy of Sciences, Beijing 100190 (China); Duan, Junhong; Hua, Helin [Department of Materials Chemistry, Nanchang Hangkong University, Nanchang 330063 (China); Yu, Changlin, E-mail: yuchanglinjx@163.com [School of Metallurgy and Chemical Engineering, Jiangxi University of Science and Technology, Ganzhou 341000 (China); Gao, Yunhua [Key Laboratory of Photochemical Conversion and Optoelectronic Materials, TIPC, Chinese Academy of Sciences, Beijing 100190 (China); Huang, Yan; Pan, Jianfei; Ling, Yun [Department of Materials Chemistry, Nanchang Hangkong University, Nanchang 330063 (China)

    2015-05-05

    Carbon-encapsulated NiZn ferrite magnetic nanocomposites were successfully synthesized by an inexpensive and environment-friendly method of in-situ starch coating route combined with hydrogen thermal reduction. The nanocomposites were characterized in detail by X-ray diffraction (XRD), Fourier transform infrared spectrometry (FT-IR), thermogravimetric analysis (TGA), transmission electron microscopy (TEM) and vibrate sample magnetometer (VSM) and so on techniques. XRD, FT-IR, TGA and TEM images indicate the formation of carbon-encapsulated NiZn ferrite magnetic nanocomposites. XRD patterns reveal that the crystalline structure of the nanocomposites is cubic spinel and taenite emerges under the hydrogen thermal reductive ambient. FT-IR spectra suggest that there are interactions on the NiZn ferrite nanocomposites and a spinel-type structure corresponding to NiZn ferrite has formed. TGA shows that the weight loss of the nanocomposites can be divided into three stages in the course of heat decomposition. TEM observations reveal that the carbon-encapsulated NiZn ferrite magnetic nanocomposites have an intact core–shell structure. Under the magnetic field, the nanocomposites exhibited the ferrimagnetic behavior. The saturated magnetization (M{sub s}) of carbon-encapsulated NiZn ferrite nanocomposites calcined at 400 °C can reach a high value up to 72.67 emu/g, and the saturated magnetization (M{sub s}) decreases as the annealing temperature goes up, while the coercivity (Hc), magnetic residual (Mr) magnetic parameters practically fixed on 115.15 Oe and 7.85 emu/g. - Graphical abstract: Carbon-encapsulated NiZn ferrite magnetic nanocomposites were successfully synthesized by an inexpensive and environment-friendly method of in-situ starch coating route combined with hydrogen thermal reduction (Fig. 1). The nanocomposites were characterized and the experimental results were discussed. Under applied magnetic field, the nanocomposites exhibited the ferromagnetic behavior

  1. Using ß-cyclodextrin and Arabic Gum as Wall Materials for Encapsulation of Saffron Essential Oil.

    Science.gov (United States)

    Atefi, Mohsen; Nayebzadeh, Kooshan; Mohammadi, Abdorreza; Mortazavian, Amir Mohammad

    2017-01-01

    Saffron essential oil has a pleasant aroma and medicinal activities. However, it is sensible into the environmental condition. Therefore, it should be protected against unwanted changes during storage or processing. Encapsulation is introduced as a process by which liable materials are protected from unwanted changes. In the present study, different ratios (0:100, 25:75, 50:50, 75:25, and 100:0) of ß-cyclodextrin (ß-CD) and arabic gum (GA) were used as wall martial for encapsulation saffron essential oil. In order to calculate of loading capacity (LC) and encapsulation efficiency (EE), and release (RE), safranal was determined as indicator of saffron essential oil using GC. According to the results, the highest LC and EE were related to the mixture of ß-CD/GA at a 75:25 ratio. In contrast, the lowest encapsulate hygroscopicity (EH) and RE were observed when only ß-CD was applied as wall material (P≤0.05). Comparing the differential scanning calorimetry (DSC) thermograms of the control and encapsulate of ß-CD/GA (75:25) confirmed encapsulation of saffron essential oil. Scanning electron microscopy (SEM) images with high magnifications showed the rhombic structure that partially coated by GA. The mixture of ß-CD/GA at a 75:25 ratio can be recommended for saffron essential oil encapsulation.

  2. Alginate Encapsulation of Pluripotent Stem Cells Using a Co-axial Nozzle.

    Science.gov (United States)

    Horiguchi, Ikki; Sakai, Yasuyuki

    2015-07-02

    Pluripotent stem cells (PS cells) are the focus of intense research due to their role in regenerative medicine and drug screening. However, the development of a mass culture system would be required for using PS cells in these applications. Suspension culture is one promising culture method for the mass production of PS cells, although some issues such as controlling aggregation and limiting shear stress from the culture medium are still unsolved. In order to solve these problems, we developed a method of calcium alginate (Alg-Ca) encapsulation using a co-axial nozzle. This method can control the size of the capsules easily by co-flowing N₂ gas. The controllable capsule diameter must be larger than 500 µm because too high a flow rate of N₂ gas causes the breakdown of droplets and thus heterogeneous-sized capsules. Moreover, a low concentration of Alg-Na and CaCl₂ causes non-spherical capsules. Although an Alg-Ca capsule without a coating of Alg-PLL easily dissolves enabling the collection of cells, they can also potentially leak out from capsules lacking an Alg-PLL coating. Indeed, an alginate-PLL coating can prevent cellular leakage but is also hard to break. This technology can be used to research the stem cell niche as well as the mass production of PS cells because encapsulation can modify the micro-environment surrounding cells including the extracellular matrix and the concentration of secreted factors.

  3. Thermally Induced Encapsulation of Food Nutrients into Phytoferritin through the Flexible Channels without Additives.

    Science.gov (United States)

    Yang, Rui; Tian, Jing; Liu, Yuqian; Yang, Zhiying; Wu, Dandan; Zhou, Zhongkai

    2017-11-22

    The cavity of phytoferritin provides a nanospace to encapsulate and deliver food nutrient molecules. However, tranditional methods to prepare the ferritin-nutrient complexes must undergo acid/alkaline conditions or apply additives. In this work, we provide a novel guideline that thermal treatment at 60 °C can expand ferritin channels by uncoiling the surrounding α-helix. Upon reduction of the temperature to 20 °C, food nutrient rutin can be encapsulated in apo-soybean seed ferritin (apoSSF) at pH 7.0 through channels without disassembly of the protein cage and with no addition of additives. Results indicated that one apoSSF could encapsulate about 10.5 molecules of rutin, with an encapsulation ratio of 8.08% (w/w). In addition, the resulting rutin-loaded SSF complexes were monodispersed in a size of 12 nm in aqueous solution. This work provides a novel pathway for the encapsulation of food nutrient molecules into the nanocavity of ferritin under a neutral pH condition induced by thermal treatment.

  4. Whey microbeads as a matrix for the encapsulation and immobilisation of riboflavin and peptides.

    Science.gov (United States)

    O'Neill, Graham J; Egan, Thelma; Jacquier, Jean Christophe; O'Sullivan, Michael; Dolores O'Riordan, E

    2014-10-01

    Whey microbeads manufactured using a cold-set gelation process, have been used to encapsulate bioactives. In this study whey microbeads were used to encapsulate riboflavin using 2 methods. Riboflavin was added to the microbead forming solution however diffusional losses of riboflavin occurred during the subsequent bead preparation. To overcome riboflavin loss, a second approach to 'load' whey microbeads by soaking in riboflavin was assessed. Significantly (p⩽0.05) higher concentrations of riboflavin were obtained in 'loaded' microbeads (361 mg/L) compared to riboflavin added to the microbead forming solution (48 mg/L). Riboflavin uptake by the microbeads was shown to be via a partition process. As partitioning is often driven by hydrophobic interactions the uptake of amino acids and peptides of varying hydrophobicities by the microbeads was examined. The % encapsulation increased with increasing molecule hydrophobicity with a maximum of 89% encapsulation. Whey microbeads are well suited to act as sorbents for encapsulation. Copyright © 2014 Elsevier Ltd. All rights reserved.

  5. Complexation/encapsulation of green tea polyphenols in mixed calcium carbonate and phosphate micro-particles.

    Science.gov (United States)

    Elabbadi, Amal; Jeckelmann, Nicolas; Haefliger, Olivier P; Ouali, Lahoussine

    2011-01-01

    We used a double-jet mixer to encapsulate water-soluble polyphenols, green tea extract (GTE), with calcium-based inorganic materials. The device mixed calcium chloride solutions with a solution of carbonate and phosphate in the presence of a GTE solution, and formed micro-particles which capture the GTE molecules. The micro-particles were analysed by liquid chromatography coupled to tandem mass spectroscopy to determine the encapsulation yield and loading of the different GTE components. We established correlations between (1) the efficiency of the GTE encapsulation and the composition of the mixed anion solutions and (2) the protonation degree of the ions and the molar ratio of calcium cations and carbonate/phosphate anions. An optimal and reproducible GTE loading of about 40% with an encapsulation yield of 65% was observed for a carbonate/phosphate molar composition of 4 : 1. In addition, our experimental results showed that the process is selective and favours the encapsulation of gallated species which form stronger complexes with calcium cations.

  6. Photovoltaic manufacturing technology (PVMaT). Annual subcontract report, March 31, 1994--June 30, 1995

    Energy Technology Data Exchange (ETDEWEB)

    Holley, W A [Springborn Labs., Inc., Enfield, CT (United States)

    1996-01-01

    This report describes work performed under a subcontract to the National Renewable Energy Laboratory under the Photovoltaic Manufacturing Technology Project. The objectives of this subcontract are to (1) define the problem of yellowing/browning of EVA-based encapsulants; (2) determine probable mechanisms and the role of various parameters such as heat, UV exposure, module construction, EVA interfaces, and EVA thickness, in the browning of EVA-based encapsulants; (3) develop stabilization strategies for various module constructions to protect the encapsulant from degradative failure; (4) conduct laboratory, accelerated outdoor, and field testing of encapsulant, laminated test coupons, and full modules to demonstrate the functional adequacy of the stabilization strategies; and (5) implement these strategies. This report summarizes the accomplishments related to the above goals for the reporting period.

  7. Enhanced AFCI Sampling, Analysis, and Safeguards Technology Review

    Energy Technology Data Exchange (ETDEWEB)

    John Svoboda

    2009-09-01

    The focus of this study includes the investigation of sampling technologies used in industry and their potential application to nuclear fuel processing. The goal is to identify innovative sampling methods using state of the art techniques that could evolve into the next generation sampling and analysis system for metallic elements. Sampling and analysis of nuclear fuel recycling plant processes is required both to monitor the operations and ensure Safeguards and Security goals are met. In addition, environmental regulations lead to additional samples and analysis to meet licensing requirements. The volume of samples taken by conventional means, can restrain productivity while results samples are analyzed, require process holding tanks that are sized to meet analytical issues rather than process issues (and that create a larger facility footprint), or, in some cases, simply overwhelm analytical laboratory capabilities. These issues only grow when process flowsheets propose new separations systems and new byproduct material for transmutation purposes. Novel means of streamlining both sampling and analysis are being evaluated to increase the efficiency while meeting all requirements for information. This report addresses just a part of the effort to develop and study novel methods by focusing on the sampling and analysis of aqueous samples for metallic elements. It presents an overview of the sampling requirements, including frequency, sensitivity, accuracy, and programmatic drivers, to demonstrate the magnitude of the task. The sampling and analysis system needed for metallic element measurements is then discussed, and novel options being applied to other industrial analytical needs are presented. Inductively coupled mass spectrometry instruments are the most versatile for metallic element analyses and are thus chosen as the focus for the study. Candidate novel means of process sampling, as well as modifications that are necessary to couple such instruments to

  8. Encapsulation of strontium aluminate phosphors to enhance water resistance and luminescence

    International Nuclear Information System (INIS)

    Zhu Yong; Zeng Jianghua; Li Wenyu; Xu Li; Guan Qiu; Liu Yingliang

    2009-01-01

    Strontium aluminate SrAl 2 O 4 :Eu 2+ ,Dy 3+ phosphors are chemically unstable against water or even moisture. To enhance the water resistance of the phosphors, an encapsulation was performed by direct surface reactions with phosphoric acid (H 3 PO 4 ). The morphology, surface structure, surface element composition, water resistance, luminescence, and photoacoustic spectrum of the phosphors before and after encapsulation were discussed. Experimental results showed that phosphors were perfectly encapsulated by amorphous layers in nanoscale and crystalline layers in microscale under different conditions. The water resistance of phosphors was greatly enhanced by the two types of layer. More importantly, the amorphous layers enhanced the luminescence of phosphors markedly. The possible mechanism for the enhancements was also proposed.

  9. Encapsulation and Hemocyte Numbers in Crocidolomia pavonana and Spodoptera litura Fabricius (Lepidoptera Attacked by Parasitoid Eriborus argenteopilosus Cameron (Hymenoptera

    Directory of Open Access Journals (Sweden)

    DAMAYANTI BUCHORI

    2009-12-01

    Full Text Available Eriborus argenteopilosus is the most important parasitoid attacking cabbage pest Crocidolomia pavonana in Indonesia. Previous studies proved that parasitoid encapsulation was found to be an important factor limiting the effectiveness of the parasitoid in controlling pest population in the field. Since 1998, we have conducted series studies to investigate encapsulation mechanism developed by hosts against parasitoid, responses of parasitoid toward encapsulation ability and to determine factors that may help parasitoid avoid encapsulation. Parasitoid responses were examined on two different hosts C. pavonana and Spodoptera litura. Our findings showed that parasitization level was found to be high both on C. pavonana and S. litura. Encapsulation occurred to be high in all larva stages of C. pavonana, in contrast encapsulation was recorded very low in all larvae stages of S. litura. We recorded that encapsulation in the larval body of C. pavonana was completed in 72 hours and mostly occurred in higher larval stage. Melanization was only recorded in encapsulated parasitoid inside larva body of C. pavonana, not in S. litura. We recorded that encapsulation increased blood cell number of both larvae C. pavonana and S. litura. Encapsulation may affect development of immature parasitoid. Weight of S. litura's pupae containing encapsulated parasitoid was found to be lower in S. litura, but not in C. pavonana. Our investigation also proved that superparasitism may help parasitoid avoid encapsulation.

  10. Diamond-Like Carbon Coatings as Encapsulants for Photovoltaic Solar Cells

    International Nuclear Information System (INIS)

    Pern, F. J.; Panosyan, Zh.; Gippius, A. A.; Kontsevoy, J. A.; Touryan, K.; Voskanyan, S.; Yengibaryan, Y.

    2005-01-01

    High-quality single-layer and bilayer diamond-like carbon (DLC) thin films are fabricated by two technologies, namely, ion-assisted plasma-enhanced deposition (IAPED) and electron cyclotron resonance (ECR) deposition. Deposition on various substrates, such as sapphires and solar cells, has been performed at low substrate temperatures (50 ∼ 80 C). The two deposition technologies allow good control over the growth conditions to produce DLC films with desired optical properties, thickness, and energy bandgap. The bilayer-structured DLC can be fabricated by using IAPED for the bottom layer followed by ECR for the top layer, or just by IAPED for both layers with different compositions. The DLC films have shown good spatial uniformity, density, microhardness, and adhesion strength. They exhibit excellent stability against attack by strong acids, prolonged damp-heat exposure at 85 C and 85% relative humidity, mechanical scratch, ultrasonication, and irradiation by ultraviolet (UV), protons, and electrons. When deposited on crystalline Si and GaAs solar cells in single-layer and/or bilayer structure, the DLC films not only serve as antireflection coating and protective encapsulant, but also improve the cell efficiencies

  11. Co-encapsulation of lyoprotectants improves the stability of protein-loaded PLGA nanoparticles upon lyophilization

    DEFF Research Database (Denmark)

    Fonte, Pedro; Araújo, Francisca; Seabra, Vítor

    2015-01-01

    The purpose of this work was to evaluate the influence of the co-encapsulation of lyoprotectants with insulin into PLGA nanoparticles, on the stability of the protein and nanoparticles upon lyophilization. Different lyoprotectants were used, namely trehalose, glucose, sucrose, fructose and sorbitol...... formulations with externally added lyoprotectants, except trehalose, showed crystallinity. FTIR assessment showed that co-encapsulating lyoprotectants better preserved insulin structure upon lyophilization with a spectral area overlap of 82-87%, compared to only 72% in lyoprotectant absence. These results were...... confirmed by circular dichroism spectroscopy. Surprisingly, the simultaneous co-encapsulation and addition of lyoprotectants was detrimental to protein stabilization. The insulin in vitro release studies demonstrated that formulations with co-encapsulated trehalose, glucose, sucrose, fructose and sorbitol...

  12. Trust in technology a socio-technical perspective

    CERN Document Server

    Clarke, Karen; Rouncefield, Mark

    2006-01-01

    Encapsulates work done in the DIRC project (Interdisciplinary Research Collaboration in Dependability), bringing together a range of disciplinary approaches - computer science, sociology and software engineering - to produce a socio-technical systems perspective on the issues surrounding trust in technology in complex settings.

  13. Application of Electrostatic Extrusion – Flavour Encapsulation and Controlled Release

    OpenAIRE

    Manojlovic, Verica; Rajic, Nevenka; Djonlagic, Jasna; Obradovic, Bojana; Nedovic, Viktor; Bugarski, Branko

    2008-01-01

    The subject of this study was the development of flavour alginate formulations aimed for thermally processed foods. Ethyl vanilline was used as the model flavour compound. Electrostatic extrusion was applied for the encapsulation of ethyl vanilline in alginate gel microbeads. The obtained microbeads with approx. 10 % w/w of ethyl vanilline encapsulated in about 2 % w/w alginate were uniformly sized spheres of about 450 ?m. Chemical characterization by H-NMR spectroscopy revealed that the algi...

  14. Efficient Asymmetric Index Encapsulation Scheme for Anonymous Content Centric Networking

    Directory of Open Access Journals (Sweden)

    Rong Ma

    2017-01-01

    Full Text Available Content Centric Networking (CCN is an effective communication paradigm that well matches the features of wireless environments. To be considered a viable candidate in the emerging wireless networks, despite the clear benefits of location-independent security, CCN must at least have parity with existing solutions for confidential and anonymous communication. This paper designs a new cryptographic scheme, called Asymmetric Index Encapsulation (AIE, that enables the router to test whether an encapsulated header matches the token without learning anything else about both of them. We suggest using the AIE as the core protocol of anonymous Content Centric Networking. A construction of AIE which strikes a balance between efficiency and security is given. The scheme is proved to be secure based on the DBDH assumption in the random oracle with tight reduction, while the encapsulated header and the token in our system consist of only three elements.

  15. Modification of encapsulation pressure of reverse micelles in liquid ethane.

    Science.gov (United States)

    Peterson, Ronald W; Nucci, Nathaniel V; Wand, A Joshua

    2011-09-01

    Encapsulation within reverse micelles dissolved in low viscosity fluids offers a potential solution to the slow tumbling problem presented by large soluble macromolecules to solution NMR spectroscopy. The reduction in effective macromolecular tumbling is directly dependent upon the viscosity of the solvent. Liquid ethane is of sufficiently low viscosity at pressures below 5000 psi to offer a significant advantage. Unfortunately, the viscosity of liquid ethane shows appreciable pressure dependence. Reverse micelle encapsulation in liquid ethane often requires significantly higher pressures, which obviates the potential advantages offered by liquid ethane over liquid propane. Addition of co-surfactants or co-solvents can be used to manipulate the minimum pressure required to obtain stable, well-behaved solutions of reverse micelles prepared in liquid ethane. A library of potential additives is examined and several candidates suitable for use with encapsulated proteins are described. Copyright © 2011 Elsevier Inc. All rights reserved.

  16. Encapsulation of black carrot juice using spray and freeze drying.

    Science.gov (United States)

    Murali, S; Kar, Abhijit; Mohapatra, Debabandya; Kalia, Pritam

    2015-12-01

    Black carrot juice extracted using pectinase enzyme was encapsulated in three different carrier materials (maltodextrin 20DE, gum arabic and tapioca starch) using spray drying at four inlet temperatures (150, 175, 200 and 225 ℃) and freeze drying at a constant temperature of - 53 ℃ and vacuum of 0.22-0.11 mbar with the constant feed mixture. The products were analyzed for total anthocyanin content, antioxidant activity, water solubility index, encapsulation efficiency and total colour change. For both the drying methods followed in this study, maltodextrin 20DE as the carrier material has proven to be better in retaining maximum anthocyanin and antioxidant activity compared to gum arabic and tapioca starch. The best spray dried product, was obtained at 150 ℃. The most acceptable was the freeze dried product with maximum anthocyanin content, antioxidant activity, water solubility index, encapsulation efficiency and colour change. © The Author(s) 2014.

  17. Encapsulation of Mg-Zr alloy in metakaolin-based geo-polymer

    International Nuclear Information System (INIS)

    Rooses, Adrien; Steins, Prune; Dannoux-Papin, Adeline; Lambertin, David; Poulesquen, Arnaud; Frizon, Fabien

    2013-01-01

    Investigations were carried out to propose a suitable material for the encapsulation of Mg-Zr alloy wastes issued from fuel cladding of the first generation nuclear reactors. Stability over time, good mechanical properties and low gas production are the main requirements that embedding matrices must comply with in order to be suitable for long run storage. One of the main issues encapsulating Mg-Zr alloy in mineral binder is the hydrogen production related to Mg-Zr alloys corrosion and water radiolysis process. In this context, metakaolin geo-polymers offer an interesting outlook: corrosion densities of Mg-Zr alloys are significantly lower than in Portland cement. This work firstly presents the hydrogen production of Mg-Zr alloy embedded in geo-polymers prepared from different the activation solution (NaOH or KOH). The effect of addition of fluorine on the magnesium corrosion in geo-polymer has been investigated too. The results point out that sodium geo-polymer is a suitable binder for Mg-Zr alloy encapsulation with respect to magnesium corrosion resistance. Furthermore the presence of fluorine reduces significantly the hydrogen release. Then, the impact of fluorine on the geo-polymer network formation was studied by rheological, calorimetric and 19 F NMR measurements. No direct effect resulting from the addition of fluorine has been shown on the geo-polymer binder. Secondly, the formulation of the encapsulation matrix has been adjusted to fulfil the expected physical and mechanical properties. Observations, dimensional evolutions and compressive strengths demonstrated that addition of sand to the geo-polymer binder is efficient to meet the storage criteria. Consequently, a matrix formulation compatible with Mg-Zr alloy encapsulation has been proposed. Finally, irradiation tests have been carried out to assess the hydrogen radiolytic yield of the matrix under exposure to γ radiation. (authors)

  18. Encapsulation and handling of spent nuclear fuel for final disposal

    International Nuclear Information System (INIS)

    Loennerberg, B.; Larker, H.; Ageskog, L.

    1983-05-01

    The handling and embedding of those metal parts which arrive to the encapsulation station with the fuel is described. For the encapsulation of fuel two alternatives are presented, both with copper canisters but with filling of lead and copper powder respectively. The sealing method in the first case is electron beam welding, in the second case hot isostatic pressing. This has given the headline of the two chapters describing the methods: Welded copper canister and Pressed copper canister. Chapter 1, Welded copper canister, presents the handling of the fuel when it arrives to the encapsulation station, where it is first placed in a buffer pool. From this pool the fuel is transferred to the encapsulation process and thereby separated from fuel boxes and boron glass rod bundles, which are transported together with the fuel. The encapsulation process comprises charging into a copper canister, filling with molten lead, electron beam welding of the lid and final inspection. The transport to and handling in the final repository are described up to the deposition and sealing in the deposition hole. Handling of fuel residues is treated in one of the sections. In chapter 2, Pressed copper canister, only those parts of the handling, which differ from chapter 1 are described. The hot isostatic pressing process is given in the first sections. The handling includes drying, charging into the canister, filling with copper powder, seal lid application and hot isostatic pressing before the final inspection and deposition. In the third chapter, BWR boxes in concrete moulds, the handling of the metal parts, separated from the fuel, are dealt with. After being lifted from the buffer pool they are inserted in a concrete mould, the mould is filled with concrete, covered with a lid and after hardening transferred to its own repository. The deposition in this repository is described. (author)

  19. Effect of cationic grafted copolymer structure on the encapsulation of bovine serum albumin

    International Nuclear Information System (INIS)

    Flynn, Nicholas; Topal, Ç. Özge; Hikkaduwa Koralege, Rangika S.; Hartson, Steve; Ranjan, Ashish; Liu, Jing; Pope, Carey; Ramsey, Joshua D.

    2016-01-01

    The aim of the present study was to evaluate a library of poly-L-lysine (PLL)-graft (g)-polyethylene glycol (PEG) copolymers for the ability to encapsulate effectively a model protein, bovine serum albumin (BSA), and to characterize the stability and protein function of the resulting nanoparticle. A library of nine grafted copolymers was produced by varying PLL molecular weight and PEG grafting ratio. Electrostatic self-assembly of the protein and the grafted copolymer drove encapsulation. The formation of protein/polymer nanoparticles with a core/shell structure was confirmed using PAGE, dynamic light scattering, and electron microscopy. Encapsulation of the BSA into nanoparticles was strongly dependent on the copolymer-to-protein mass ratio, PEG grafting ratio, and PLL molecular weight. A copolymer-to-protein mass ratio of 7:1 and higher was generally required for high levels of encapsulation, and under these conditions, no loss of protein activity was observed. Copolymer characteristics also influenced nanoparticle resistance to polyanions and protease degradation. The results indicate that a copolymer of 15–30 kDa PLL, with a PEG grafting ratio of 10:1, is most promising for protein delivery. - Highlights: • A 4–70 kDa range of PLL-g-PEG copolymers was able to encapsulate BSA into NPs. • Encapsulation of BSA by PLL-g-PEG not only retained but increased esterolytic activity. • NPs were stable against protease degradation and polyanion dissociation.

  20. Effect of cationic grafted copolymer structure on the encapsulation of bovine serum albumin

    Energy Technology Data Exchange (ETDEWEB)

    Flynn, Nicholas [School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078 (United States); Topal, Ç. Özge [School of Mechanical and Aerospace Engineering, Oklahoma State University, Stillwater, OK 74078 (United States); Hikkaduwa Koralege, Rangika S. [School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078 (United States); Hartson, Steve [Department of Biochemistry and Molecular Biology, Oklahoma State University, Stillwater, OK 74078 (United States); Ranjan, Ashish; Liu, Jing; Pope, Carey [Department of Physiological Sciences, Oklahoma State University, Stillwater, OK 74078 (United States); Ramsey, Joshua D., E-mail: josh.ramsey@okstate.edu [School of Chemical Engineering, Oklahoma State University, Stillwater, OK 74078 (United States)

    2016-05-01

    The aim of the present study was to evaluate a library of poly-L-lysine (PLL)-graft (g)-polyethylene glycol (PEG) copolymers for the ability to encapsulate effectively a model protein, bovine serum albumin (BSA), and to characterize the stability and protein function of the resulting nanoparticle. A library of nine grafted copolymers was produced by varying PLL molecular weight and PEG grafting ratio. Electrostatic self-assembly of the protein and the grafted copolymer drove encapsulation. The formation of protein/polymer nanoparticles with a core/shell structure was confirmed using PAGE, dynamic light scattering, and electron microscopy. Encapsulation of the BSA into nanoparticles was strongly dependent on the copolymer-to-protein mass ratio, PEG grafting ratio, and PLL molecular weight. A copolymer-to-protein mass ratio of 7:1 and higher was generally required for high levels of encapsulation, and under these conditions, no loss of protein activity was observed. Copolymer characteristics also influenced nanoparticle resistance to polyanions and protease degradation. The results indicate that a copolymer of 15–30 kDa PLL, with a PEG grafting ratio of 10:1, is most promising for protein delivery. - Highlights: • A 4–70 kDa range of PLL-g-PEG copolymers was able to encapsulate BSA into NPs. • Encapsulation of BSA by PLL-g-PEG not only retained but increased esterolytic activity. • NPs were stable against protease degradation and polyanion dissociation.

  1. Encapsulation of nanoparticles into single-crystal ZnO nanorods and microrods

    Directory of Open Access Journals (Sweden)

    Jinzhang Liu

    2014-04-01

    Full Text Available One-dimensional single crystal incorporating functional nanoparticles of other materials could be an interesting platform for various applications. We studied the encapsulation of nanoparticles into single-crystal ZnO nanorods by exploiting the crystal growth of ZnO in aqueous solution. Two types of nanodiamonds with mean diameters of 10 nm and 40 nm, respectively, and polymer nanobeads with size of 200 nm have been used to study the encapsulation process. It was found that by regrowing these ZnO nanorods with nanoparticles attached to their surfaces, a full encapsulation of nanoparticles into nanorods can be achieved. We demonstrate that our low-temperature aqueous solution growth of ZnO nanorods do not affect or cause degradation of the nanoparticles of either inorganic or organic materials. This new growth method opens the way to a plethora of applications combining the properties of single crystal host and encapsulated nanoparticles. We perform micro-photoluminescence measurement on a single ZnO nanorod containing luminescent nanodiamonds and the spectrum has a different shape from that of naked nanodiamonds, revealing the cavity effect of ZnO nanorod.

  2. Niosomal encapsulation of ethambutol hydrochloride for increasing its efficacy and safety.

    Science.gov (United States)

    El-Ridy, Mohammed Shafik; Yehia, Soad Aly; Kassem, Mahfouz Abd-El-Megeid; Mostafa, Dina Mahmoud; Nasr, Essam Amin; Asfour, Marwa Hasanin

    2015-01-01

    Tuberculosis (TB) is a worldwide health concern. In 2011, about 8.7 million new cases developed TB and 1.4 million people died from it. Enhancement of ethambutol hydrochloride activity and safety in treatment of TB through niosomal encapsulation. Niosomes were prepared by the thin-film hydration method. They were characterized, investigated for in vitro release, lung disposition and in vivo biological evaluation. Entrapment efficiency of ethambutol hydrochloride ranged from 12.20% to 25.81%. Zeta potential values inferred stability of neutral and negatively charged formulations. In vitro release was biphasic. Lung targeting was increased by niosomal encapsulation. Biological evaluation revealed superiority of niosomal ethambutol hydrochloride over the free drug. Neutral and negatively charged niosomal vesicles are dispersed homogenously unlike positively charged vesicles. Niosomal encapsulation results in controlled drug release. Niosomal formulations targeted more drugs to mice lungs for a prolonged period of time resulting in: decreased root-specific lung weight, bacterial counts in lung homogenates and optimizing pathological effect on guinea pigs lungs, livers and spleens. Encapsulation of ethambutol hydrochloride in niosomal formulations for the treatment of TB provides higher efficacy and safety compared with the free drug.

  3. Encapsulation-Induced Stress Helps Saccharomyces cerevisiae Resist Convertible Lignocellulose Derived Inhibitors

    Directory of Open Access Journals (Sweden)

    Johan O. Westman

    2012-09-01

    Full Text Available The ability of macroencapsulated Saccharomyces cerevisiae CBS8066 to withstand readily and not readily in situ convertible lignocellulose-derived inhibitors was investigated in anaerobic batch cultivations. It was shown that encapsulation increased the tolerance against readily convertible furan aldehyde inhibitors and to dilute acid spruce hydrolysate, but not to organic acid inhibitors that cannot be metabolized anaerobically. Gene expression analysis showed that the protective effect arising from the encapsulation is evident also on the transcriptome level, as the expression of the stress-related genes YAP1, ATR1 and FLR1 was induced upon encapsulation. The transcript levels were increased due to encapsulation already in the medium without added inhibitors, indicating that the cells sensed low stress level arising from the encapsulation itself. We present a model, where the stress response is induced by nutrient limitation, that this helps the cells to cope with the increased stress added by a toxic medium, and that superficial cells in the capsules degrade convertible inhibitors, alleviating the inhibition for the cells deeper in the capsule.

  4. Hybrid Encapsulated Ionic Liquids for Post-Combustion Carbon Dioxide (CO2) Capture

    Energy Technology Data Exchange (ETDEWEB)

    Brennecke, Joan F [Univ. of Texas, Austin, TX (United States); Degnan, Jr, Thomas Francis [Univ. of Notre Dame, IN (United States); McCready, Mark J. [Univ. of Notre Dame, IN (United States); Stadtherr, Mark A. [Univ. of Texas, Austin, TX (United States); Stolaroff, Joshua K [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Ye, Congwang [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2017-11-03

    Ionic liquids (ILs) and Phase Change Ionic Liquids (PCILs) are excellent materials for selective removal of carbon dioxide from dilute post-combustion streams. However, they are typically characterized as having high viscosities, which impairs their effectiveness due to mass transfer limitations, caused by the high viscosities. In this project, we are examining the benefits of encapsulating ILs and PCILs in thin polymeric shells to produce particles of approximately 100 to 600 µm in diameter that can be used in a fluidized bed absorber. The particles are produced by microencapsulation of the ILs and PCILs in CO2-permeable polymer shells. Here we report on the encapsulation of the IL and PCIL materials, thermodynamic testing of the encapsulated materials, mass transfer measurements in both a fluidized bed and a packed bed, determination of the effect of impurities (SO2, NOx and water) on the free and encapsulated IL and PCIL, recyclability of the CO2 uptake, selection and synthesis of kg quantities of the IL and PCIL, identification of scale-up methods for encapsulation and production of a kg quantity of the PCIL, construction and shakedown of the laboratory scale unit to test the encapsulated particles for CO2 capture ability and efficiency, use of our mass transfer model to predict mass transfer and identify optimal properties of the encapsulated particles, and initial testing of the encapsulated particles in the laboratory scale unit. We also show our attempts at developing shell materials that are resistant to water permeation. Overall, we have shown that the selected IL and PCIL can be successfully encapsulated in polymer shells and the methods scaled up to production levels. The IL/PCIL and encapsulated IL/PCIL react irreversibly with SO2 and NOx so the CO2 capture unit would need to be placed after the flue gas desulfurization and NOx reduction units. However

  5. Defining Threshold Values of Encapsulant and Backsheet Adhesion for PV Module Reliability: Preprint

    Energy Technology Data Exchange (ETDEWEB)

    Bosco, Nicholas S [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Kurtz, Sarah [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Eafanti, Joshua [National Renewable Energy Laboratory (NREL), Golden, CO (United States); Tracy, Jared [Stanford University; Dauskardt, Reinhold [Stanford University

    2017-08-28

    The width-tapered cantilever beam method is used to quantify the debond energy (adhesion) of encapsulant and backsheet structures of 27 modules collected from the field. The collected population of modules contains both those that have remained in-tact and those with instances of either or both encapsulant and backsheet delamination. From this survey, initial threshold values (an adhesion value above which a module should remain intact throughout its lifetime) for encapsulant and backsheet interfaces are proposed. For encapsulants this value is about 60 J/m2 and for backsheets about 20 J/m2. It is expected that these values will continue to be refined and evolve as the width-tapered cantilever beam method becomes adopted by the PV industry, and that they may aid in the future improvement of accelerated lifetime tests and the development of new, low-cost materials.

  6. Comparative studies on osmosis based encapsulation of sodium diclofenac in porcine and outdated human erythrocyte ghosts.

    Science.gov (United States)

    Bukara, Katarina; Drvenica, Ivana; Ilić, Vesna; Stančić, Ana; Mišić, Danijela; Vasić, Borislav; Gajić, Radoš; Vučetić, Dušan; Kiekens, Filip; Bugarski, Branko

    2016-12-20

    The objective of our study was to develop controlled drug delivery system based on erythrocyte ghosts for amphiphilic compound sodium diclofenac considering the differences between erythrocytes derived from two readily available materials - porcine slaughterhouse and outdated transfusion human blood. Starting erythrocytes, empty erythrocyte ghosts and diclofenac loaded ghosts were compared in terms of the encapsulation efficiency, drug releasing profiles, size distribution, surface charge, conductivity, surface roughness and morphology. The encapsulation of sodium diclofenac was performed by an osmosis based process - gradual hemolysis. During this process sodium diclofenac exerted mild and delayed antihemolytic effect and increased potassium efflux in porcine but not in outdated human erythrocytes. FTIR spectra revealed lack of any membrane lipid disorder and chemical reaction with sodium diclofenac in encapsulated ghosts. Outdated human erythrocyte ghosts with detected nanoscale damages and reduced ability to shrink had encapsulation efficiency of only 8%. On the other hand, porcine erythrocyte ghosts had encapsulation efficiency of 37% and relatively slow drug release rate. More preserved structure and functional properties of porcine erythrocytes related to their superior encapsulation and release performances, define them as more appropriate for the usage in sodium diclofenac encapsulation process. Copyright © 2016 Elsevier B.V. All rights reserved.

  7. Dendrimer encapsulated Silver nanoparticles as novel catalysts for reduction of aromatic nitro compounds

    Science.gov (United States)

    Asharani, I. V.; Thirumalai, D.; Sivakumar, A.

    2017-11-01

    Polyethylene glycol (PEG) core dendrimer encapsulated silver nanoparticles (AgNPs) were synthesized through normal chemical reduction method, where dendrimer acts as reducing and stabilizing agent. The encapsulated AgNPs were well characterized using TEM, DLS and XPS techniques. The synthesized AgNPs showed excellent catalytic activity towards the reduction of aromatic nitro compounds with sodium borohydride as reducing agent and the results substantiate that dendrimer encapsulated AgNPs can be an effective catalyst for the substituted nitro aromatic reduction reactions. Also the kinetics of different nitro compounds reductions was studied and presented.

  8. Mars Sample Return: Mars Ascent Vehicle Mission and Technology Requirements

    Science.gov (United States)

    Bowles, Jeffrey V.; Huynh, Loc C.; Hawke, Veronica M.; Jiang, Xun J.

    2013-01-01

    A Mars Sample Return mission is the highest priority science mission for the next decade recommended by the recent Decadal Survey of Planetary Science, the key community input process that guides NASAs science missions. A feasibility study was conducted of a potentially simple and low cost approach to Mars Sample Return mission enabled by the use of developing commercial capabilities. Previous studies of MSR have shown that landing an all up sample return mission with a high mass capacity lander is a cost effective approach. The approach proposed is the use of an emerging commercially available capsule to land the launch vehicle system that would return samples to Earth. This paper describes the mission and technology requirements impact on the launch vehicle system design, referred to as the Mars Ascent Vehicle (MAV).

  9. Alginate micro-encapsulation of mesenchymal stromal cells enhances modulation of the neuro-inflammatory response.

    Science.gov (United States)

    Stucky, Elizabeth C; Schloss, Rene S; Yarmush, Martin L; Shreiber, David I

    2015-10-01

    Modulation of inflammation after brain trauma is a key therapeutic goal aimed at limiting the consequences of the subsequent injury cascade. Mesenchymal stromal cells (MSCs) have been demonstrated to dynamically regulate the inflammatory environment in several tissue systems, including the central nervous system. There has been limited success, however, with the use of direct implantation of cells in the brain caused by low viability and engraftment at the injury site. To circumvent this, we encapsulated MSCs in alginate microspheres and evaluated the ability of these encapsulated MSCs to attenuate inflammation in rat organotypic hippocampal slice cultures (OHSC). OHSC were administered lipopolysaccharide to induce inflammation and immediately co-cultured with encapsulated or monolayer human MSCs. After 24 h, culture media was assayed for the pro-inflammatory cytokine tumor necrosis factor-alpha (TNF-α) produced by OHSC, as well as MSC-produced trophic mediators. Encapsulated MSCs reduced TNF-α more effectively than did monolayer MSCs. Additionally, there was a strong correlation between increased prostaglandin E2 (PGE2) and reduction of TNF-α. In contrast to monolayer MSCs, inflammatory signals were not required to stimulate PGE2 production by encapsulated MSCs. Further encapsulation-stimulated changes were revealed in a multiplex panel analyzing 27 MSC-produced cytokines and growth factors, from which additional mediators with strong correlations to TNF-α levels were identified. These results suggest that alginate encapsulation of MSCs may not only provide an improved delivery vehicle for transplantation but may also enhance MSC therapeutic benefit for treating neuro-inflammation. Copyright © 2015. Published by Elsevier Inc.

  10. Nutritional management of encapsulating peritoneal sclerosis with ...

    African Journals Online (AJOL)

    Keywords: intradialytic parenteral nutrition, nutritional management, encapsulating peritoneal sclerosis ... reflection of fluid retention and the underlying inflammatory process, ... The patient appeared weak and frail, with severe generalised muscle ... was recommended on diagnosis of EPS to prevent further peritoneal.

  11. Encapsulated Bacillus anthracis interacts closely with liver endothelium.

    Science.gov (United States)

    Piris-Gimenez, Alejandro; Corre, Jean-Philippe; Jouvion, Gregory; Candela, Thomas; Khun, Huot; Goossens, Pierre L

    2009-11-01

    The Bacillus anthracis poly-gamma-D-glutamate capsule is essential for virulence. It impedes phagocytosis and protects bacilli from the immune system, thus promoting systemic dissemination. To further define the virulence mechanisms brought into play by the capsule, we characterized the interactions between encapsulated nontoxinogenic B. anthracis and its host in vivo through histological analysis, perfusion, and competition experiments with purified capsule. Clearance of encapsulated bacilli from the blood was rapid (>90% clearance within 5 min), with 75% of the bacteria being trapped in the liver. Competition experiments with purified capsule polyglutamate inhibited this interaction. At the septicemic phase of cutaneous infection with spores, the encapsulated bacilli were trapped in the vascular spaces of the liver and interacted closely with the liver endothelium in the sinusoids and terminal and portal veins. They often grow as microcolonies containing capsular material shed by the bacteria. We show that, in addition to its inhibitory effect on the interaction with the immune system, the capsule surrounding B. anthracis plays an active role in mediating the trapping of the bacteria within the liver and may thus contribute to anthrax pathogenesis. Because other microorganisms produce polyglutamate, it may also represent a general mechanism of virulence or in vivo survival.

  12. Novel Thermal Storage Technologies for Concentrating Solar Power Generation

    Energy Technology Data Exchange (ETDEWEB)

    Neti, Sudhakar [Lehigh Univ., Bethlehem, PA (United States). Mechanical Engineering and Mechanics; Oztekin, Alparslan [Lehigh Univ., Bethlehem, PA (United States); Chen, John [Lehigh Univ., Bethlehem, PA (United States); Tuzla, Kemal [Lehigh Univ., Bethlehem, PA (United States); Misiolek, Wojciech [Lehigh Univ., Bethlehem, PA (United States)

    2013-06-20

    The technologies that are to be developed in this work will enable storage of thermal energy in 100 MWe solar energy plants for 6-24 hours at temperatures around 300°C and 850°C using encapsulated phase change materials (EPCM). Several encapsulated phase change materials have been identified, fabricated and proven with calorimetry. Two of these materials have been tested in an airflow experiment. A cost analysis for these thermal energy storage systems has also been conducted that met the targets established at the initiation of the project.

  13. Human bone marrow stem cell-encapsulating calcium phosphate scaffolds for bone repair

    Science.gov (United States)

    Weir, Michael D.; Xu, Hockin H.K.

    2010-01-01

    Due to its injectability and excellent osteoconductivity, calcium phosphate cement (CPC) is highly promising for orthopedic applications. However, a literature search revealed no report on human bone marrow mesenchymal stem cell (hBMSC) encapsulation in CPC for bone tissue engineering. The aim of this study was to encapsulate hBMSCs in alginate hydrogel beads and then incorporate them into CPC, CPC–chitosan and CPC–chitosan–fiber scaffolds. Chitosan and degradable fibers were used to mechanically reinforce the scaffolds. After 21 days, that the percentage of live cells and the cell density of hBMSCs inside CPC-based constructs matched those in alginate without CPC, indicating that the CPC setting reaction did not harm the hBMSCs. Alkaline phosphate activity increased by 8-fold after 14 days. Mineral staining, scanning electron microscopy and X-ray diffraction confirmed that apatitic mineral was deposited by the cells. The amount of hBMSC-synthesized mineral in CPC–chitosan–fiber matched that in CPC without chitosan and fibers. Hence, adding chitosan and fibers, which reinforced the CPC, did not compromise hBMSC osteodifferentiation and mineral synthesis. In conclusion, hBMSCs were encapsulated in CPC and CPC–chitosan–fiber scaffolds for the first time. The encapsulated cells remained viable, osteodifferentiated and synthesized bone minerals. These self-setting, hBMSC-encapsulating CPC-based constructs may be promising for bone tissue engineering applications. PMID:20451676

  14. Encapsulation in alginate-skim milk microspheres improves viability of Lactobacillus bulgaricus in stimulated gastrointestinal conditions.

    Science.gov (United States)

    Pan, Ling-Xia; Fang, Xiu-Juan; Yu, Zhen; Xin, Yang; Liu, Xiao-Ying; Shi, Lu-E; Tang, Zhen-Xing

    2013-05-01

    Lactobacillus delbrueckii subsp. bulgaricus (L. bulgaricus) was encapsulated in alginate-skim milk microspheres. Characteristics of encapsulated L. bulgaricus, such as pH stability, bile stability, storage stability and release property, were studied in this paper. The viability of free L. bulgaricus was not observed after 1 min in simulated gastric fluids (SGF) at pH 2.5 or 2.0. Compared with that of free L. bulgaricus, the viability of encapsulated L. bulgaricus only decreased 0.7 log CFU/g and 2 log CFU/g after 2.0 h incubation in SGF at pH 2.5 and pH 2.0, respectively. L. bulgaricus was also sensitive to bile solution. The viability of free L. bulgaricus was fully lost after 1 h incubation in 1 and 2% bile solution, while the viability of encapsulated L. bulgaricus was only lost 2 log CFU/g and 2.6 log CFU/g in 1 and 2% bile solution at the same time, respectively. Encapsulated L. bulgaricus could be completely released from microspheres in simulated intestinal fluid (pH 6.8) within 2 h. The viability of encapsulated L. bulgaricus retained around 8 log CFU/g when stored at 4°C for 30 days. The current encapsulation technique enables a large proportion of L. bulgaricus to remain good bioactive in a simulated gastrointestinal tract environment.

  15. Encapsulation of protease from Aspergillus oryzae and lipase from Thermomyces lanuginoseus using alginate and different copolymer types

    Directory of Open Access Journals (Sweden)

    Truong Thi Mong Thu

    2016-05-01

    Full Text Available Although the application of enzymes in food as a food processing aid and enzyme supplement is of interest and widely used, the enzymes can be easily deactivated or lose their activity due to many causes such as pH and moisture as well as through the introduction of incompatible ingredients during food processing and storage. These problems can be solved by the encapsulation technique, especially in a gel matrix. The influences were studied of the alginate concentration, types of copolymer and their concentrations on the bead size, encapsulation yield (EY, encapsulation efficiency (EE, leakage and the retention of enzyme activity during storage period of encapsulated protease from Aspergillus oryzae and lipase from Thermomyces lanuginosus beads. A solution of purified protease or lipase was encapsulated in calcium alginate-chitosan beads (CACB, calcium alginate-xanthan gum beads (CAXB and calcium alginate-maltodextrin beads (CAMB using the extrusion method. Increasing the alginate and copolymer concentrations in the solution increased the bead size, EY, EE and the retention of enzyme activity during the storage period and reduced leakage of both the encapsulated protease and lipase. In addition, different types of copolymer significantly (p ≤ 0.05 affected these properties of both encapsulated enzymes. Furthermore, protease encapsulated using 2.0% alginate and 0.2% chitosan provided the highest EY (81.7% and EE (77.2% with a bead size of 1.85 mm and 8.1% leakage. The retention of encapsulated protease activity and the shelf-life of encapsulated enzyme which was expressed as half-life, the time required for the enzyme activity to decrease by half (thalf life were 75.8% and 27.2 wk, respectively after storage at 4 °C for 10 wk. For lipase, encapsulation using 2.0% alginate and 0.4% xanthan gum provided the highest EY (42.5% and EE (43.9% and the bead size and leakage were 1.81 mm and 6.2%, respectively. The retention of encapsulated

  16. Encapsulation of phytosterols and phytosterol esters in liposomes made with soy phospholipids by high pressure homogenization.

    Science.gov (United States)

    Wang, Fan C; Acevedo, Nuria; Marangoni, Alejandro G

    2017-11-15

    Phytosterols and phytosterol esters were encapsulated within large unilamellar liposomes prepared with soy phospholipids using a microfluidizer. The average particle diameter of these liposomal vesicles increased with increasing amounts of encapsulated phytosterols, especially with increasing free sterol content. The phytosterol content, liposomal particle size, and phytosterol encapsulation efficiency started to plateau when liposomes were prepared with MOPS buffer dispersions that contained 50 mg ml -1 soy phospholipid and more than 4% phytosterol blend, suggesting the saturation of phytosterol encapsulation. We proposed an encapsulation mechanism of free sterols and phytosterol esters in liposomes, where free sterols were mainly encapsulated within the lumen of these liposomes as crystals, and sterol esters and some free sterols were incorporated within the phospholipid bilayer of the liposomal membrane. The results from this work could provide the pharmaceutical and nutraceutical industries a practical method to produce loaded liposomes using inexpensive phospholipid mixtures for the delivery of bioactive ingredients.

  17. Equipment evaluation for low density polyethylene encapsulated nitrate salt waste at the Rocky Flats Plant

    International Nuclear Information System (INIS)

    Yamada, W.I.; Faucette, A.M.; Jantzen, R.C.; Logsdon, B.W.; Oldham, J.H.; Saiki, D.M.; Yudnich, R.J.

    1993-01-01

    Mixed wastes at the Rocky Flats Plant (RFP) are subject to regulation by the Resource Conservation and Recovery Act (RCRA). Polymer solidification is being developed as a final treatment technology for several of these mixed wastes, including nitrate salts. Encapsulation nitrate salts with low density polyethylene (LDPE) has been the preliminary focus of the RFP polymer solidification effort. Literature reviews, industry surveys, and lab-scale and pilot-scale tests have been conducted to evaluate several options for encapsulating nitrate salts with LDPE. Most of the effort has focused on identifying compatible drying and extrusion technologies. Other processing options, specifically meltration and non-heated compounding machines, were also investigated. The best approach appears to be pretreatment of the nitrate salt waste brine in either a vertical or horizontal thin film evaporator followed by compounding of the dried waste with LDPE in an intermeshing, co-rotating, twin-screw extruder. Additional pilot-scale tests planned for the fall of 1993 should further support this recommendation. Preliminary evaluation work indicates that meltration is not possible at atmospheric pressure with the LDPE (Chevron PE-1409) provided by RFP. However, meltration should be possible at atmospheric pressure using another LDPE formulation with altered physical and rheological properties: Lower molecular weight and lower viscosity (Epoline C-15). Contract modifications are now in process to allow a follow-on pilot scale demonstration. Questions regarding changed safety and physical properties of the resultant LDPE waste form due to use of the Epoline C-15 will be addressed. No additional work with non-heated mixer compounder machines is planned at this time

  18. Nano- and micro-structured assemblies for encapsulation of food ingredients.

    Science.gov (United States)

    Augustin, Mary Ann; Hemar, Yacine

    2009-04-01

    This tutorial review provides an overview of the science of food materials and encapsulation techniques that underpin the development of delivery vehicles for functional food components, nutrients and bioactives. Examples of how the choice of materials, formulation and process affect the structure of micro- and nano-encapsulated ingredients and the release of the core are provided. The review is of relevance to chemists, material scientists, food scientists, engineers and nutritionists who are interested in addressing delivery challenges in the food and health industries.

  19. Emergence of DNA-encapsulating liposomes from a DNA-lipid blend film

    Science.gov (United States)

    Shimobayashi, Shunsuke; Hishida, Mafumi; Kurimura, Tomo; Ichikawa, Masatoshi

    A Micro-scale giant unilamellar vesicle (GUV) densely encapsulating molecular systems is one of the simplest life-mimicking model systems. The dehydration-rehydration process proposed by Deamer et al. more than 30 years ago generates vesicles to satisfy the constraints of micro-scale size, unilamellarity and densely polymer-encapsulation. Nevertheless, the physico-chemical mechanism of a set of dehydration-rehydration process has been poorly understood. The present study reveals crucial factors on the process through fluorescent microscopic observation and small angle x-ray scattering. From the results, we propose a plausible physical mechanism for the process, making it possible to optimize the encapsulation of any agent This work was supported by Grant-in-Aid for JSPS Fellows Grant (No. 25-1270) and by KAKENHI (Nos. 26707020, 25103012, and 26115709).

  20. Titanium dioxide encapsulation of supported Ag nanoparticles on the porous silica bead for increased photocatalytic activity

    Science.gov (United States)

    Liu, Hui; Deng, Lu; Sun, Chaochao; Li, Junqi; Zhu, Zhenfeng

    2015-01-01

    A new synthetic strategy has been developed to encapsulate Ag nanoparticles in heterogeneous catalysts to prevent their dropping and sintering. Ag nanoparticles with diameters about 5-10 nm were first supported on the porous silica bead. These were then covered with a fresh layer of titanium dioxide with the thickness about 5 nm. SEM and TEM images were used to confirm the success of each synthesis step, and the photocatalytic activity of the as-synthesized samples was evaluated by photocatalytic decolorization of Rhodamine B (Rh B) aqueous solution at ambient temperature under both UV and visible light irradiation. The resulting titanium dioxide encapsulated Ag nanoparticles exhibited an enhanced photocatalytic activity under both UV and visible light irradiation, this can be attributed to effective charge separation and light harvesting of the plasmonic silver nanoparticles decoration, even the reducing of the exciton recombination rate caused by the small grain size of anatase TiO2 nanocrystals.

  1. Ultrathin nitrogen-doped graphitized carbon shell encapsulating CoRu bimetallic nanoparticles for enhanced electrocatalytic hydrogen evolution

    Science.gov (United States)

    Xu, You; Li, Yinghao; Yin, Shuli; Yu, Hongjie; Xue, Hairong; Li, Xiaonian; Wang, Hongjing; Wang, Liang

    2018-06-01

    Design of highly active and cost-effective electrocatalysts is very important for the generation of hydrogen by electrochemical water-splitting. Herein, we report the fabrication of ultrathin nitrogen-doped graphitized carbon shell encapsulating CoRu bimetallic nanoparticles (CoRu@NCs) and demonstrate their promising feasibility for efficiently catalyzing the hydrogen evolution reaction (HER) over a wide pH range. The resultant CoRu@NC nanohybrids possess an alloy–carbon core–shell structure with encapsulated low-ruthenium-content CoRu bimetallic alloy nanoparticles (10–30 nm) as the core and ultrathin nitrogen-doped graphitized carbon layers (2–6 layers) as the shell. Remarkably, the optimized catalyst (CoRu@NC-2 sample) with a Ru content as low as 2.04 wt% shows superior catalytic activity and excellent durability for HER in acidic, neutral, and alkaline conditions. This work offers a new method for the design and synthesis of non-platium-based electrocatalysts for HER in all-pH.

  2. Technologies for pre-screening IAEA swipe samples

    International Nuclear Information System (INIS)

    Smith, Nicholas A.; Steeb, Jennifer L.; Lee, Denise L.; Huckabay, Heath A.; Ticknor, Brian W.

    2015-01-01

    During the course of International Atomic Energy Agency (IAEA) inspections, many samples are taken for the purpose of verifying the declared facility activities and identifying any possible undeclared activities. One of these sampling techniques is the environmental swipe sample. Due to the large number of samples collected, and the amount of time that is required to analyze them, prioritizing these swipes in the field or upon receipt at the Network of Analytical Laboratories (NWAL) will allow sensitive or mission-critical analyses to be performed sooner. As a result of this study, technologies were placed into one of three categories: recommended, promising, or not recommended. Both neutron activation analysis (NAA) and X-ray fluorescence (XRF) are recommended for further study and possible field deployment. These techniques performed the best in initial trials for pre-screening and prioritizing IAEA swipes. We learned that for NAA more characterization of cold elements (such as calcium and magnesium) would need to be emphasized, and for XRF it may be appropriate to move towards a benchtop XRF versus a handheld XRF due to the increased range of elements available on benchtop equipment. Promising techniques that will require additional research and development include confocal Raman microscopy, fluorescence microscopy, and infrared (IR) microscopy. These techniques showed substantive responses to uranium compounds, but expensive instrumentation upgrades (confocal Raman) or university engagement (fluorescence microscopy) may be necessary to investigate the utility of the techniques completely. Point-and-shoot (handheld) Raman and attenuated total reflectance–infrared (ATR-IR) measurements are not recommended, as they have not shown enough promise to continue investigations.

  3. Technologies for pre-screening IAEA swipe samples

    Energy Technology Data Exchange (ETDEWEB)

    Smith, Nicholas A. [Argonne National Lab. (ANL), Argonne, IL (United States); Steeb, Jennifer L. [Argonne National Lab. (ANL), Argonne, IL (United States); Lee, Denise L. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Huckabay, Heath A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Ticknor, Brian W. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2015-11-09

    During the course of International Atomic Energy Agency (IAEA) inspections, many samples are taken for the purpose of verifying the declared facility activities and identifying any possible undeclared activities. One of these sampling techniques is the environmental swipe sample. Due to the large number of samples collected, and the amount of time that is required to analyze them, prioritizing these swipes in the field or upon receipt at the Network of Analytical Laboratories (NWAL) will allow sensitive or mission-critical analyses to be performed sooner. As a result of this study, technologies were placed into one of three categories: recommended, promising, or not recommended. Both neutron activation analysis (NAA) and X-ray fluorescence (XRF) are recommended for further study and possible field deployment. These techniques performed the best in initial trials for pre-screening and prioritizing IAEA swipes. We learned that for NAA more characterization of cold elements (such as calcium and magnesium) would need to be emphasized, and for XRF it may be appropriate to move towards a benchtop XRF versus a handheld XRF due to the increased range of elements available on benchtop equipment. Promising techniques that will require additional research and development include confocal Raman microscopy, fluorescence microscopy, and infrared (IR) microscopy. These techniques showed substantive responses to uranium compounds, but expensive instrumentation upgrades (confocal Raman) or university engagement (fluorescence microscopy) may be necessary to investigate the utility of the techniques completely. Point-and-shoot (handheld) Raman and attenuated total reflectance–infrared (ATR-IR) measurements are not recommended, as they have not shown enough promise to continue investigations.

  4. Encapsulation of Adenovirus Serotype 5 in Anionic Lecithin Liposomes using a Bead-Based Immunoprecipitation Technique Enhances Transfection Efficiency

    Science.gov (United States)

    Mendez, N.; Herrera, V.; Zhang, L.; Hedjran, F.; Feuer, R.; Blair, S.; Trogler, W.; Reid, T.

    2014-01-01

    Oncolytic viruses (OVs) constitute a promising class of cancer therapeutics which exploit validated genetic pathways known to be deregulated in many cancers. To overcome an immune response and to enhance its potential use to treat primary and metastatic tumors, a method for liposomal encapsulation of adenovirus has been developed. The encapsulation of adenovirus in non-toxic anionic lecithin-cholesterol-PEG liposomes ranging from 140–180nm in diameter have been prepared by self-assembly around the viral capsid. The encapsulated viruses retain their ability to infect cancer cells. Furthermore, an immunoprecipitation (IP) technique has shown to be a fast and effective method to extract non-encapsulated viruses and homogenize the liposomes remaining in solution. 78% of adenovirus plaque forming units were encapsulated and retained infectivity after IP processing. Additionally, encapsulated viruses have shown enhanced transfection efficiency up to 4× higher compared to non-encapsulated Ads. Extracting non-encapsulated viruses from solution may prevent an adverse in vivo immune response and may enhance treatment for multiple administrations. PMID:25154663

  5. Encapsulation of adenovirus serotype 5 in anionic lecithin liposomes using a bead-based immunoprecipitation technique enhances transfection efficiency.

    Science.gov (United States)

    Mendez, Natalie; Herrera, Vanessa; Zhang, Lingzhi; Hedjran, Farah; Feuer, Ralph; Blair, Sarah L; Trogler, William C; Reid, Tony R; Kummel, Andrew C

    2014-11-01

    Oncolytic viruses (OVs) constitute a promising class of cancer therapeutics which exploit validated genetic pathways known to be deregulated in many cancers. To overcome an immune response and to enhance its potential use to treat primary and metastatic tumors, a method for liposomal encapsulation of adenovirus has been developed. The encapsulation of adenovirus in non-toxic anionic lecithin-cholesterol-PEG liposomes ranging from 140 to 180 nm in diameter have been prepared by self-assembly around the viral capsid. The encapsulated viruses retain their ability to infect cancer cells. Furthermore, an immunoprecipitation (IP) technique has shown to be a fast and effective method to extract non-encapsulated viruses and homogenize the liposomes remaining in solution. 78% of adenovirus plaque forming units were encapsulated and retained infectivity after IP processing. Additionally, encapsulated viruses have shown enhanced transfection efficiency up to 4 × higher compared to non-encapsulated Ads. Extracting non-encapsulated viruses from solution may prevent an adverse in vivo immune response and may enhance treatment for multiple administrations. Copyright © 2014 Elsevier Ltd. All rights reserved.

  6. Secure Hybrid Encryption from Weakened Key Encapsulation

    NARCIS (Netherlands)

    D. Hofheinz (Dennis); E. Kiltz (Eike); A. Menezes

    2007-01-01

    textabstractWe put forward a new paradigm for building hybrid encryption schemes from constrained chosen-ciphertext secure (CCCA) key-encapsulation mechanisms (KEMs) plus authenticated symmetric encryption. Constrained chosen-ciphertext security is a new security notion for KEMs that we propose. It

  7. Encapsulation technology of MR6 spent fuel and quality analysis of the EK-10 and WWR-SM spent fuel stored more than 30 years in wet conditions

    Energy Technology Data Exchange (ETDEWEB)

    Borek-Kruszewska, E.; Bykowski, W.; Chwaszczewski, S.; Czajkowski, W.; Madry, M. [Institute of Atomic Energy, Otwock -Swierk (Poland)

    2002-07-01

    The research reactor MARIA has been in operation for more than twenty years and all the spent fuel assemblies used since the first commissioning of the reactor are stored in wet facility on site. The present paper deals with the spent fuel MR-6 encapsulation technology in MARIA reactor. The encapsulated spent MR-6 fuel will be stored under water in the same pool unless some other solution is available. The capsules made of stainless steel are capable to accommodate one MR-6 fuel assembly. The encapsulation process is performed in the hot cell by the MARIA reactor. The spent fuel having its leg cut off is loaded to the transport cylinder manually and next transferred to a trolley. The trolley is moving to a position directly below the entrance to the hot cell and the spent fuel is entering the hot cell. The spent fuel assembly is then put into the drying cell. Dried out spent fuel is moved into the capsule mounted on the grip of the machine. Next, the capsule lid is pressed in and welded. After the leak test and filling up with helium the capsule returns from the hot cell to the pool. The hermetic capsule is sunk back into the water and positioned in the separator . The results presented earlier show, that the limiting time of WWR-SM and Ek-10 type spent fuel residence in wet storage is about 40-45 years. Therefore, the systematic quality investigation of all Ek-10 fuel elements and WWR-SM fuel assemblies discharged from EWA reactor in the period of 1959-1969 was performed. Altogether, about 2500 Ek-10 fuel elements and 47 WWR-SM fuel assemblies were investigated. The results of these investigations are presented in the present work. The sipping test, visual investigation and ultrasonic techniques were used for that purpose. The radioactive isotope Cs-137 was used as the indicator of fission product release from the fuel assembly. Taking into account the value of Cs-137 release from damaged WWR-SM fuel assembly the criteria of damaged fuel assembly were proposed. It

  8. Nootkatone encapsulation by cyclodextrins: Effect on water solubility and photostability.

    Science.gov (United States)

    Kfoury, Miriana; Landy, David; Ruellan, Steven; Auezova, Lizette; Greige-Gerges, Hélène; Fourmentin, Sophie

    2017-12-01

    Nootkatone (NO) is a sesquiterpenoid volatile flavor, used in foods, cosmetics and pharmaceuticals, possessing also insect repellent activity. Its application is limited because of its low aqueous solubility and stability; this could be resolved by encapsulation in cyclodextrins (CDs). This study evaluated the encapsulation of NO by CDs using phase solubility studies, Isothermal Titration Calorimetry, Nuclear Magnetic Resonance spectroscopy and molecular modeling. Solid CD/NO inclusion complex was prepared and characterized for encapsulation efficiency and loading capacity using UV-Visible. Thermal properties were investigated by thermogravimetric-differential thermal analysis and release studies were performed using multiple headspace extraction. Formation constants (K f ) proved the formation of stable inclusion complexes. NO aqueous solubility, photo- and thermal stability were enhanced and the release could be insured from solid complex in aqueous solution. This suggests that CDs are promising carrier to improve NO properties and, consequently, to enlarge its use in foods, cosmetics, pharmaceuticals and agrochemicals preparations. Copyright © 2016 Elsevier Ltd. All rights reserved.

  9. Zeolite encapsulation of H2

    International Nuclear Information System (INIS)

    Cooper, S.; Lakner, J.F.

    1982-08-01

    Experiments with H 2 have shown that it is possible to encapsulate gases in the structure of certain molecular sieves. This method may offer a better means of temporarily storing and disposing of tritium over some others presently in use. The method may also prove safer, and may enable isotope separation, and removal of 3 He. Initial experiments were performed with H 2 to screen potential candidates for use with tritium

  10. Poly(ester-anhydride):poly(beta-amino ester) micro- and nanospheres: DNA encapsulation and cellular transfection.

    Science.gov (United States)

    Pfeifer, Blaine A; Burdick, Jason A; Little, Steve R; Langer, Robert

    2005-11-04

    Poly(ester-anhydride) delivery devices allow flexibility regarding carrier dimensions (micro- versus nanospheres), degradation rate (anhydride versus ester hydrolysis), and surface labeling (through the anhydride functional unit), and were therefore tested for DNA encapsulation and transfection of a macrophage P388D1 cell line. Poly(l-lactic acid-co-sebacic anhydride) and poly(l-lactic acid-co-adipic anhydride) were synthesized through melt condensation, mixed with 25 wt.% poly(beta-amino ester), and formulated with plasmid DNA (encoding firefly luciferase) into micro- and nanospheres using a double emulsion/solvent evaporation technique. The micro- and nanospheres were then characterized (size, morphology, zeta potential, DNA release) and assayed for DNA encapsulation and cellular transfection over a range of poly(ester-anhydride) copolymer ratios. Poly(ester-anhydride):poly(beta-amino ester) composite microspheres (6-12 microm) and nanospheres (449-1031 nm), generated with copolymers containing between 0 and 25% total polyanhydride content, encapsulated plasmid DNA (>or=20% encapsulation efficiency). Within this polyanhydride range, poly(adipic anhydride) copolymers provided DNA encapsulation at an increased anhydride content (10%, microspheres; 10-25%, nanospheres) compared to poly(sebacic anhydride) copolymers (1%, microspheres and nanospheres) with cellular transfection correlating with the observed DNA encapsulation.

  11. Encapsulation of nodal cuttings and shoot tips for storage and exchange of cassava germplasm.

    Science.gov (United States)

    Danso, K E; Ford-Lloyd, B V

    2003-04-01

    We report the encapsulation of in vitro-derived nodal cuttings or shoot tips of cassava in 3% calcium alginate for storage and germplasm exchange purposes. Shoot regrowth was not significantly affected by the concentration of sucrose in the alginate matrix while root formation was. In contrast, increasing the sucrose concentration in the calcium chloride polymerisation medium significantly reduced regrowth from encapsulated nodal cuttings of accession TME 60444. Supplementing the alginate matrix with increased concentrations of 6-benzylaminopurine and alpha-naphthaleneacetic acid enhanced complete plant regrowth within 2 weeks. Furthermore, plant regrowth by encapsulated nodal cuttings and shoot tips was significantly affected by the duration of the storage period as shoot recovery decreased from almost 100% to 73.3% for encapsulated nodal cuttings and 94.4% to 60% for shoot tips after 28 days of storage. The high frequency of plant regrowth from alginate-coated micropropagules coupled with high viability percentage after 28 days of storage is highly encouraging for the exchange of cassava genetic resources. Such encapsulated micropropagules could be used as an alternative to synthetic seeds derived from somatic embryos.

  12. The Effect of Silybin Encapsulated in Nanoparticles on oprM Gene Expression in Drug Resistant Isolates of Pseudomonas Aeruginosa

    Directory of Open Access Journals (Sweden)

    Aref Mohammadipour

    2017-08-01

    Full Text Available Abstract Background: Pseudomonas aeruginosa is an opportunistic nosocomial pathogen that using several classes of antibiotics to treat has been led to the emergence of multiple drug resistance. One of the drug resistance mechanisms in Pseudomonas aeruginosa is overexpression of mexXY-oprM efflux pump system. Silybin as main flavonolignan of silymarin extracted from Silybum marianum is a hepatoprotective agent that its anti-bacterial properties was studied, recently. In this study, the effect of combination of silybin and ciprofloxacin on oprM gene expression in clinical isolates of Pseudomonas aeruginosa was evaluated. Materials and Methods: In this study, seven ciprofloxacin resistant isolates of Pseudomonas aeruginosa were treated by ciprofloxacin (1/2MIC only (control sample and in the combination with silybin-encapsulated micelle (nanoparticles (test sample. After 24h, RNA extraction and cDNA synthesis were performed in silybin treated and un-treated cells and oprM gene expression was quantitatively investigated by realtime PCR method. Results: Results of this study showed that a silybin encapsulated in nanoparticles (400µg/ml induces death up to 50% in resistant isolates treated by ciprofloxacin (1/2MIC during 24h. Also, quantitative Real-Time PCR analysis revealed that silybin encapsulated in nanoparticles decreases the expression of oprM gene compared to silybin untreated cells. Conclusion: It seems that Decrease of oprM expression in resistant isolates lead to decrease of mexAB-oprM and mexXY-oprM in cell surface, subsequently decrease of antibiotic withdrawal to extracellular environment and increase of sensitivity to antibiotics.

  13. Secure Encapsulation and Publication of Biological Services in the Cloud Computing Environment

    Science.gov (United States)

    Zhang, Weizhe; Wang, Xuehui; Lu, Bo; Kim, Tai-hoon

    2013-01-01

    Secure encapsulation and publication for bioinformatics software products based on web service are presented, and the basic function of biological information is realized in the cloud computing environment. In the encapsulation phase, the workflow and function of bioinformatics software are conducted, the encapsulation interfaces are designed, and the runtime interaction between users and computers is simulated. In the publication phase, the execution and management mechanisms and principles of the GRAM components are analyzed. The functions such as remote user job submission and job status query are implemented by using the GRAM components. The services of bioinformatics software are published to remote users. Finally the basic prototype system of the biological cloud is achieved. PMID:24078906

  14. Secure Encapsulation and Publication of Biological Services in the Cloud Computing Environment

    Directory of Open Access Journals (Sweden)

    Weizhe Zhang

    2013-01-01

    Full Text Available Secure encapsulation and publication for bioinformatics software products based on web service are presented, and the basic function of biological information is realized in the cloud computing environment. In the encapsulation phase, the workflow and function of bioinformatics software are conducted, the encapsulation interfaces are designed, and the runtime interaction between users and computers is simulated. In the publication phase, the execution and management mechanisms and principles of the GRAM components are analyzed. The functions such as remote user job submission and job status query are implemented by using the GRAM components. The services of bioinformatics software are published to remote users. Finally the basic prototype system of the biological cloud is achieved.

  15. Secure encapsulation and publication of biological services in the cloud computing environment.

    Science.gov (United States)

    Zhang, Weizhe; Wang, Xuehui; Lu, Bo; Kim, Tai-hoon

    2013-01-01

    Secure encapsulation and publication for bioinformatics software products based on web service are presented, and the basic function of biological information is realized in the cloud computing environment. In the encapsulation phase, the workflow and function of bioinformatics software are conducted, the encapsulation interfaces are designed, and the runtime interaction between users and computers is simulated. In the publication phase, the execution and management mechanisms and principles of the GRAM components are analyzed. The functions such as remote user job submission and job status query are implemented by using the GRAM components. The services of bioinformatics software are published to remote users. Finally the basic prototype system of the biological cloud is achieved.

  16. Chitosan/siRNA nanoparticles encapsulated in PLGA nanofibers for siRNA delivery

    DEFF Research Database (Denmark)

    Chen, Menglin; Gao, Shan; Dong, Mingdong

    2012-01-01

    Composite nanofibers of biodegradable poly(d,l-lactic-co-glycolic acid) (PLGA) encapsulating chitosan/siRNA nanoparticles (NPs) were prepared by electrospinning. Acidic/alkaline hydrolysis and a bulk/surface degradation mechanism were investigated in order to achieve an optimized release profile...... for prolonged and efficient gene silencing. Thermo-controlled AFM in situ imaging not only revealed the integrity of the encapsulated chitosan/siRNA polyplex but also shed light on the decreasing Tg of PLGA on the fiber surfaces during release. A triphasic release profile based on bulk erosion was obtained at p......RNA transfection, where the encapsulated chitosan/siRNA NPs exhibited up to 50% EGFP gene silencing activity after 48 h post-transfection on H1299 cells....

  17. EXTRACELLULAR MIMETICS: A COMPARATIVE EVALUATION OF CELL ENCAPSULATION UTILIZING HYDROGELS AND SCAFFOLDS

    Directory of Open Access Journals (Sweden)

    Marco Antonio Vieira Grinet

    2017-01-01

    Full Text Available An in vitro encapsulation platform utilizing hydrogels and bone matrix (BM scaffolds to investigate the effects of microenvironmental parameters on encapsulated goat mesenchymal stem cells (gMSC was presented. The base encapsulation matrix was composed of a biocompatible hydrogel formed through a photoinitiated polymerization process. Different polymer concentrations were used to compare the effects of hydrogel crosslinking density on physical properties, as well as on cell viability. The potential of BM to support the growth and differentiation of gMSC was also analyzed. Both methods were compared in order to analyze viability. Structures that better allow flow of oxygen showed more promising results, whereas BM structures require a better evaluation method for concrete results.

  18. Encapsulation of hazardous wastes into agglomerates

    International Nuclear Information System (INIS)

    Guloy, A.

    1992-01-01

    The objective of this study was to investigate the feasibility of using the cementitious properties and agglomeration characteristics of coal conversion byproducts to encapsulate and immobilize hazardous waste materials. The intention was to establish an economical way of co-utilization and co-disposal of wastes. In addition, it may aid in the eradication of air pollution problems associated with the fine-powdery nature of fly ash. Encapsulation into agglomerates is a novel approach of treating toxic waste. Although encapsulation itself is not a new concept, existing methods employ high-cost resins that render them economically unfeasible. In this investigation, the toxic waste was contained in a concrete-like matrix whereby fly ash and other cementitious waste materials were utilized. The method incorporates the principles of solidification, stabilization and agglomeration. Another aspect of the study is the evaluation of the agglomeration as possible lightweight aggregates. Since fly ash is commercially used as an aggregate, it would be interesting to study the effect of incorporating toxic wastes in the strength development of the granules. In the investigation, the fly ash self-cementation process was applied to electroplating sludges as the toxic waste. The process hoped to provide a basis for delisting of the waste as hazardous and, thereby greatly minimize the cost of its disposal. Owing to the stringent regulatory requirements for hauling and disposal of hazardous waste, the cost of disposal is significant. The current practice for disposal is solidifying the waste with portland cement and dumping the hardened material in the landfill where the cost varies between $700--950/ton. Partially replacing portland cement with fly ash in concrete has proven beneficial, therefore applying the same principles in the treatment of toxic waste looked very promising

  19. Sol-gel encapsulation of pullulanase in the presence of hybrid magnetic (Fe3O4-chitosan) nanoparticles improves thermal and operational stability.

    Science.gov (United States)

    Long, Jie; Li, Xingfei; Zhan, Xiaobei; Xu, Xueming; Tian, Yaoqi; Xie, Zhengjun; Jin, Zhengyu

    2017-06-01

    Pullulanase was sol-gel encapsulated in the presence of magnetic chitosan/Fe 3 O 4 nanoparticles. The resulting immobilized pullulanase was characterized by scanning electron microscopy, vibrating sample magnetometry, Fourier transform infrared spectroscopy and thermogravimetric analysis. The results showed that the addition of pullulanase created a more regular surface on the sol-gel matrix and an enhanced magnetic response to an applied magnetic field. The maximal activity retention (83.9%) and specific activity (291.7 U/mg) of the immobilized pullulanase were observed under optimized conditions including an octyltriethoxysilane:tetraethoxysilane (OTES:TEOS) ratio of 1:2 and enzyme concentration of 0.484 mg/mL sol. The immobilized enzyme exhibited good thermal stability. When the temperature was above 60 °C, the immobilized pullulanase showed significantly higher activity than the free enzyme (p sol-gel encapsulation and co-immobilized by crosslinking-encapsulation retained 52 and 69% of their initial activity after 5 h at 62 °C, respectively, compared to 11% for the free enzyme. Moreover, the stability of the pullulanase was improved by crosslinking-encapsulation, as the enzyme retained more than 85 and 81% of its original activity after 5 and 6 consecutive reuses, respectively, compared to 80 and 72% of its original activity for simple sol-gel encapsulated enzymes. This indicated the leakage of enzyme molecules through the pores of the gel was substantially abated by cross-linking. Such immobilized pullulanase provides high stability and ease of enzyme recovery, characteristics that are advantageous for applications in the food industry that involve continuous starch processing.

  20. Encapsulation of biomaterials in porous glass-like matrices prepared via an aqueous colloidal sol-gel process

    Science.gov (United States)

    Liu, Dean-Mo; Chen, I-Wei

    2001-01-01

    The present invention provides a process for the encapsulation of biologically important proteins into transparent, porous silica matrices by an alcohol-free, aqueous, colloidal sol-gel process, and to the biological materials encapsulated thereby. The process is exemplified by studies involving encapsulated cytochrome c, catalase, myoglobin, and hemoglobin, although non-proteinaceous biomaterials, such as active DNA or RNA fragments, cells or even tissues, may also be encapsulated in accordance with the present methods. Conformation, and hence activity of the biomaterial, is successfully retained after encapsulation as demonstrated by optical characterization of the molecules, even after long-term storage. The retained conformation of the biomaterial is strongly correlated to both the rate of gelation and the subsequent drying speed of the encapsulatng matrix. Moreover, in accordance with this process, gelation is accelerated by the use of a higher colloidal solid concentration and a lower synthesis pH than conventional methods, thereby enhancing structural stability and retained conformation of the biomaterials. Thus, the invention also provides a remarkable improvement in retaining the biological activity of the encapsulated biomaterial, as compared with those involved in conventional alkoxide-based processes. It further provides new methods for the quantitative and qualitative detection of test substances that are reactive to, or catalyzed by, the active, encapsulated biological materials.

  1. Observation and Characterization of Fragile Organometallic Molecules Encapsulated in Single-Wall Carbon Nanotubes

    Directory of Open Access Journals (Sweden)

    Daisuke Ogawa

    2014-01-01

    Full Text Available Thermally fragile tris(η5-cyclopentadienylerbium (ErCp3 molecules are encapsulated in single-wall carbon nanotubes (SWCNTs with high yield. We realized the encapsulation of ErCp3 with high filling ratio by using high quality SWCNTs at an optimized temperature under higher vacuum. Structure determination based on high-resolution transmission electron microscope observations together with the image simulations reveals the presence of almost free rotation of each ErCp3 molecule in SWCNTs. The encapsulation is also confirmed by X-ray diffraction. Trivalent character of Er ions (i.e., Er3+ is confirmed by X-ray absorption spectrum.

  2. Characterization of a bonding-in-liquid technique for liquid encapsulation into MEMS devices

    International Nuclear Information System (INIS)

    Okayama, Yoshiyuki; Nakahara, Keijiro; Arouette, Xavier; Ninomiya, Takeshi; Matsumoto, Yasuaki; Orimo, Yoshinori; Hotta, Atsushi; Omiya, Masaki; Miki, Norihisa

    2010-01-01

    We demonstrate and characterize a new bonding-in-liquid technique (BiLT) for the encapsulation of liquids in MEMS devices. Liquid encapsulation enables innovative MEMS devices with various functions exploiting the unique characteristics of liquids, such as high deformation and spherical shape due to surface tension. Interfusion of air bubbles, variation of the liquid quantity and leakage of the encapsulated liquid must be avoided, or device performance will deteriorate. In BiLT, two structural layers are passively aligned and brought into contact in a solution, and the encapsulation cavities are filled uniformly with liquid, without air bubbles. A UV-curable resin is used as an adhesive that does not require heat or vacuum to bond the layers, but UV irradiation. DI water, glycerin and phosphate buffer saline were successfully encapsulated in silicon structural layers with PDMS membranes. We experimentally evaluated the bond strengths and alignment accuracy of BiLT in order to provide crucial information for the application of this process to the packaging and/or manufacturing of MEMS devices. Since conventional aligners are not applicable to BiLT, we experimentally evaluated the accuracy of an in-solution passive alignment process, which made use of matching concave and convex structures.

  3. Enhanced lifetime characteristics in flexible polymer light-emitting devices by encapsulation of epoxy/silica-coated gold nanoparticles resin (ESGR)

    International Nuclear Information System (INIS)

    Chiu, Pin-Hsiang; Huang, Chien-Jung; Yang, Cheng-Fu; Meen, Teen-Hang; Wang, Yeong-Her

    2010-01-01

    This paper reports the effects of a new multilayer encapsulation for the lifetime of flexible PLEDs on plastic substrate. The multilayer encapsulation consisted of a novel epoxy/silica-coated gold nanoparticles resin (ESGR) as the pre-encapsulation layer and a SiO 2 layer as the encapsulation cap. The ESGR was prepared by mixing UV-curable epoxy resin and powders of silica-coated gold nanoparticles. The silica-coated gold nanoparticles is a necessity because the epoxy resin is not a good moisture barrier. The flexible PLEDs with multilayer encapsulation exhibited no dark spots after being stored for over 300 h at 25 deg. C and 60% relative humidity. Also, the operational half-luminance decay time of device was 1360 h, seven times longer than that of a device without encapsulation. These results confirmed that the multilayer encapsulation, which restricted the moisture that penetrated into the devices, could be applied to the encapsulation of flexible PLEDs.

  4. Encapsulation of TRISO particle fuel in durable soda-lime-silicate glasses

    International Nuclear Information System (INIS)

    Heath, Paul G.; Corkhill, Claire L.; Stennett, Martin C.; Hand, Russell J.; Meyer, Willem C.H.M.; Hyatt, Neil C.

    2013-01-01

    Tri-Structural Isotropic (TRISO) coated particle-fuel is a key component in designs for future high temperature nuclear reactors. This study investigated the suitability of three soda lime silicate glass compositions, for the encapsulation of simulant TRISO particle fuel. A cold press and sinter (CPS) methodology was employed to produce TRISO particle–glass composites. Composites produced were determined to have an aqueous durability, fracture toughness and Vickers’ hardness comparable to glasses currently employed for the disposal of high level nuclear wastes. Sintering at 700 °C for 30 min was found to remove all interconnected porosity from the composite bodies and oxidation of the outer pyrolytic carbon layer during sintering was prevented by processing under a 5% H 2 /N 2 atmosphere. However, the outer pyrolytic carbon layer was not effectively wetted by the encapsulating glass matrix. The aqueous durability of the TRISO particle–glass composites was investigated using PCT and MCC-1 tests combined with geochemical modelling. It was found that durability was dependent on silicate and calcium solution saturation. This study provides significant advancements in the preparation of TRISO particle encapsulant waste forms. The potential for the use of non-borosilicate sintered glass composites for TRISO particle encapsulation has been confirmed, although further refinements are required

  5. Encapsulation of TRISO particle fuel in durable soda-lime-silicate glasses

    Energy Technology Data Exchange (ETDEWEB)

    Heath, Paul G.; Corkhill, Claire L.; Stennett, Martin C.; Hand, Russell J. [Immobilisation Science Laboratory, Department of Materials Science and Engineering, Robert Hadfield Building, University of Sheffield, Sheffield S1 3JD (United Kingdom); Meyer, Willem C.H.M. [Necsa, South African Nuclear Energy Corporation, PO Box 582, Pretoria, Gauteng (South Africa); Hyatt, Neil C., E-mail: n.c.hyatt@sheffield.ac.uk [Immobilisation Science Laboratory, Department of Materials Science and Engineering, Robert Hadfield Building, University of Sheffield, Sheffield S1 3JD (United Kingdom)

    2013-05-15

    Tri-Structural Isotropic (TRISO) coated particle-fuel is a key component in designs for future high temperature nuclear reactors. This study investigated the suitability of three soda lime silicate glass compositions, for the encapsulation of simulant TRISO particle fuel. A cold press and sinter (CPS) methodology was employed to produce TRISO particle–glass composites. Composites produced were determined to have an aqueous durability, fracture toughness and Vickers’ hardness comparable to glasses currently employed for the disposal of high level nuclear wastes. Sintering at 700 °C for 30 min was found to remove all interconnected porosity from the composite bodies and oxidation of the outer pyrolytic carbon layer during sintering was prevented by processing under a 5% H{sub 2}/N{sub 2} atmosphere. However, the outer pyrolytic carbon layer was not effectively wetted by the encapsulating glass matrix. The aqueous durability of the TRISO particle–glass composites was investigated using PCT and MCC-1 tests combined with geochemical modelling. It was found that durability was dependent on silicate and calcium solution saturation. This study provides significant advancements in the preparation of TRISO particle encapsulant waste forms. The potential for the use of non-borosilicate sintered glass composites for TRISO particle encapsulation has been confirmed, although further refinements are required.

  6. Optimisation of preparation conditions and properties of phytosterol liposome-encapsulating nattokinase.

    Science.gov (United States)

    Dong, Xu-Yan; Kong, Fan-Pi; Yuan, Gang-You; Wei, Fang; Jiang, Mu-Lan; Li, Guang-Ming; Wang, Zhan; Zhao, Yuan-Di; Chen, Hong

    2012-01-01

    Phytosterol liposomes were prepared using the thin film method and used to encapsulate nattokinase (NK). In order to obtain a high encapsulation efficiency within the liposome, an orthogonal experiment (L9 (3)(4)) was applied to optimise the preparation conditions. The molar ratio of lecithin to phytosterols, NK activity and mass ratio of mannite to lecithin were the main factors that influenced the encapsulation efficiency of the liposomes. Based on the results of a single-factor test, these three factors were chosen for this study. We determined the optimum extraction conditions to be as follows: a molar ratio of lecithin to phytosterol of 2 : 1, NK activity of 2500 U mL⁻¹ and a mass ratio of mannite to lecithin of 3 : 1. Under these optimised conditions, an encapsulation efficiency of 65.25% was achieved, which agreed closely with the predicted result. Moreover, the zeta potential, size distribution and microstructure of the liposomes prepared were measured, and we found that the zeta potential was -51 ± 3 mV and the mean diameter was 194.1 nm. From the results of the scanning electron microscopy, we observed that the phytosterol liposomes were round and regular in shape and showed no aggregation.

  7. Cyclodextrin-insulin complex encapsulated polymethacrylic acid based nanoparticles for oral insulin delivery.

    Science.gov (United States)

    Sajeesh, S; Sharma, Chandra P

    2006-11-15

    Present investigation was aimed at developing an oral insulin delivery system based on hydroxypropyl beta cyclodextrin-insulin (HPbetaCD-I) complex encapsulated polymethacrylic acid-chitosan-polyether (polyethylene glycol-polypropylene glycol copolymer) (PMCP) nanoparticles. Nanoparticles were prepared by the free radical polymerization of methacrylic acid in presence of chitosan and polyether in a solvent/surfactant free medium. Dynamic light scattering (DLS) experiment was conducted with particles dispersed in phosphate buffer (pH 7.4) and size distribution curve was observed in the range of 500-800 nm. HPbetaCD was used to prepare non-covalent inclusion complex with insulin and complex was analyzed by Fourier transform infrared (FTIR) and fluorescence spectroscopic studies. HPbetaCD complexed insulin was encapsulated into PMCP nanoparticles by diffusion filling method and their in vitro release profile was evaluated at acidic/alkaline pH. PMCP nanoparticles displayed good insulin encapsulation efficiency and release profile was largely dependent on the pH of the medium. Enzyme linked immunosorbent assay (ELISA) study demonstrated that insulin encapsulated inside the particles was biologically active. Trypsin inhibitory effect of PMCP nanoparticles was evaluated using N-alpha-benzoyl-L-arginine ethyl ester (BAEE) and casein as substrates. Mucoadhesive studies of PMCP nanoparticles were conducted using freshly excised rat intestinal mucosa and the particles were found fairly adhesive. From the preliminary studies, cyclodextrin complexed insulin encapsulated mucoadhesive nanoparticles appear to be a good candidate for oral insulin delivery.

  8. Liposome-encapsulated chemotherapy

    DEFF Research Database (Denmark)

    Børresen, B.; Hansen, A. E.; Kjær, A.

    2018-01-01

    Cytotoxic drugs encapsulated into liposomes were originally designed to increase the anticancer response, while minimizing off-target adverse effects. The first liposomal chemotherapeutic drug was approved for use in humans more than 20years ago, and the first publication regarding its use...... to inherent issues with the enhanced permeability and retention effect, the tumour phenomenon which liposomal drugs exploit. This effect seems very heterogeneously distributed in the tumour. Also, it is potentially not as ubiquitously occurring as once thought, and it may prove important to select patients...... not resolve the other challenges that liposomal chemotherapy faces, and more work still needs to be done to determine which veterinary patients may benefit the most from liposomal chemotherapy....

  9. Cryopreservation of human insulin expressing cells macro-encapsulated in a durable therapeutic immunoisolating device theracyte.

    Science.gov (United States)

    Yakhnenko, Ilya; Wong, Wallace K; Katkov, Igor I; Itkin-Ansari, Pamela

    2012-01-01

    Encapsulating insulin producing cells (INPCs) in an immunoisolation device have been shown to cure diabetes in rodents without the need for immunosuppression. However, micro-encapsulation in semi-solid gels raises longevity and safety concerns for future use of stem cell derived INPCs. We have focused on a durable and retrievable macro-encapsulation (> 10(6) cells) device (TheraCyte). Cryopreservation (CP) of cells preloaded into the device is highly desirable but may require prolonged exposure to cryoprotectants during loading and post-thaw manipulations. Here, we are reporting survival and function of a human islet cell line frozen as single cells or as islet-like cell clusters. The non-clusterized cells exhibited high cryosurvival after prolonged pre-freeze or post-thaw exposure to 10 percent DMSO. However, both clusterization and especially loading INPCs into the device reduced viable yield even without CP. The survived cryopreserved macro-encapsulated INPCs remained fully functional suggesting that CP of macro-encapsulated cells is a promising tool for cell based therapies.

  10. Methanation of CO2 over Zeolite-Encapsulated Nickel Nanoparticles

    DEFF Research Database (Denmark)

    Goodarzi, Farnoosh; Kang, Liqun; Wang, Feng Ryan

    2018-01-01

    in an increased metal dispersion and, consequently, a high catalytic activity for CO2 methanation. With a gas hourly space velocity of 60000 ml/g catalyst h-1 and H2/CO2=4, the zeolite-encapsulated Ni nanoparticles result in 60% conversion at 450°C, which corresponds to a site-time yield of around 304 mol CH4/mol......Efficient methanation of CO2 relies on the development of more selective and stable heterogeneous catalysts. Here we present a simple and effective method to encapsulate Ni nanoparticles in zeolite silicalite-1. In this method, the zeolite is modified by selective desilication, which creates intra...

  11. Tuning the conductance of carbon nanotubes with encapsulated molecules

    International Nuclear Information System (INIS)

    Meunier, Vincent; Sumpter, Bobby G

    2007-01-01

    It was recently shown that a molecule encapsulated inside a carbon nanotube can be used to devise a novel type of non-volatile memory element. At the heart of the mechanism for storing and reading information is the new concept of a molecular gate where the molecule acts as a passive gate that hinders the flow of electrons for a given position relative to the nanotube host. By systematically exploring the effects of encapsulation of an acceptor molecule in a series of carbon nanotubes, we show that the reliability of the memory mechanism is very sensitive to the interaction between the nanotube host and the molecule guest

  12. Encapsulation of polymer photovoltaic prototypes

    Energy Technology Data Exchange (ETDEWEB)

    Krebs, Frederik C. [The Danish Polymer Centre, RISOE National Laboratory, P.O. Box 49, DK-4000 Roskilde (Denmark)

    2006-12-15

    A simple and efficient method for the encapsulation of polymer and organic photovoltaic prototypes is presented. The method employs device preparation on glass substrates with subsequent sealing using glass fiber reinforced thermosetting epoxy (prepreg) against a back plate. The method allows for transporting oxygen and water sensitive devices outside a glove box environment after sealing and enables sharing of devices between research groups such that efficiency and stability can be evaluated in different laboratories. (author)

  13. Factors influencing insulin secretion from encapsulated islets

    NARCIS (Netherlands)

    de Haan, BJ; Faas, MM; de Vos, P

    2003-01-01

    Adequate regulation of glucose levels by a microencapsulated pancreatic islet graft requires a minute-to-minute regulation of blood glucose. To design such a transplant, it is mandatory to have sufficient insight in factors influencing the kinetics of insulin secretion by encapsulated islets. The

  14. Raman spectroscopy insight into Norovirus encapsulation in Bombyx mori cypovirus cubic microcrystals.

    Science.gov (United States)

    Mori, Hajime; Oda, Naoki; Abe, Satoshi; Ueno, Takafumi; Zhu, Wenliang; Pernstich, Chris; Pezzotti, Giuseppe

    2018-05-16

    Protein and amino acid structures of Norovirus-like particles (NoVLP) have been investigated by Raman spectroscopy before and after encapsulation into Bombyx mori cypovirus (BmCPV) cubic microcrystals, which are usually referred to as cubes or polyhedra. Two different types of tag were used in co-expression, namely VP3 and H1 tags. VP3 tag is derived from a capsid protein VP4 from BmCPV and H1 tag is N-terminal α-helix of BmCPV polyhedrin, respectively. A major capsid protein VP1 of NoVLP G11.4 was fused with H1 or VP3 tags, and then encapsulated into BmCPV polyhedra. Analyses of the spectroscopic data permitted the assignment of conformation-sensitive Raman bands to viral amino acid constituents and the observation of structural similarities or differences between differently tagged samples. Three separate Raman zones were attentioned, namely, the ring-mode structure region (1000-1500 cm -1 ), the CO and CC double-bond region and its surroundings (1500-1750 cm -1 ), and the high-frequency CH stretching region (2800-3100 cm -1 ). Structural fingerprints could be found in specific spectral zones for differently co-expressed samples. One clear characteristic of the H1-tagged VP1 polyhedra was the increase in tyrosine fraction, which played a critical role in binding neighboring strands through its unpaired negatively charged COO - sites. This feature could consistently be detected in different regions, but it was best represented by Raman signals associated with negatively charged COO - sites and H1 helices in the double-bond region. Such peculiar chemical features were revealed by two relatively broad bands at 1570 and 1630 cm -1 , which were assigned to COO - anti-symmetric stretching and amide I in 3 10 -helix extensions to α-helices at N-termini, respectively. These specific features did not display in the spectrum of the VP3-tagged VP1 polyhedra. Concurrently, a strong reduction of CH bond Raman signal was noticed in the high frequency stretching

  15. Sampling analytical tests and destructive tests for quality assurance

    International Nuclear Information System (INIS)

    Saas, A.; Pasquini, S.; Jouan, A.; Angelis, de; Hreen Taywood, H.; Odoj, R.

    1990-01-01

    In the context of the third programme of the European Communities on the monitoring of radioactive waste, various methods have been developed for the performance of sampling and measuring tests on encapsulated waste of low and medium level activity, on the one hand, and of high level activity, on the other hand. The purpose was to provide better quality assurance for products to be stored on an interim or long-term basis. Various testing sampling means are proposed such as: - sampling of raw waste before conditioning and determination of the representative aliquot, - sampling of encapsulated waste on process output, - sampling of core specimens subjected to measurement before and after cutting. Equipment suitable for these sampling procedures have been developed and, in the case of core samples, a comparison of techniques has been made. The results are described for the various analytical tests carried out on the samples such as: - mechanical tests, - radiation resistance, - fire resistance, - lixiviation, - determination of free water, - biodegradation, - water resistance, - chemical and radiochemical analysis. Every time it was possible, these tests were compared with non-destructive tests on full-scale packages and some correlations are given. This word has made if possible to improve and clarify sample optimization, with fine sampling techniques and methodologies and draw up characterization procedures. It also provided an occasion for a first collaboration between the laboratories responsible for these studies and which will be furthered in the scope of the 1990-1994 programme

  16. Encapsulation of Volatile Citronella Essential Oil by Coacervation: Efficiency and Release Study

    Science.gov (United States)

    Manaf, M. A.; Subuki, I.; Jai, J.; Raslan, R.; Mustapa, A. N.

    2018-05-01

    The volatile citronella essential oil was encapsulated by simple coacervation and complex coacervation using Arabic gum and gelatin as wall material. Glutaraldehyde was used in the methodology as crosslinking agent. The citronella standard calibration graph obtained with R2 of 0.9523 was used for the accurate determination of encapsulation efficiency and release study. The release kinetic was analysed based on Fick"s law of diffusion for polymeric system and linear graph of Log fraction release over Log time was constructed to determine the release rate constant, k and diffusion coefficient, n. Both coacervation methods in the present study produce encapsulation efficiency around 94%. The produced capsules for both coacervation processes were discussed based on the capsules morphology and release kinetic mechanisms.

  17. Alginate-encapsulation of shoot tips of jojoba [Simmondsia chinensis (Link) Schneider] for germplasm exchange and distribution.

    Science.gov (United States)

    Kumar, Sunil; Rai, Manoj K; Singh, Narender; Mangal, Manisha

    2010-12-01

    Shoot tips excised from in vitro proliferated shoots derived from nodal explants of jojoba [Simmondsia chinensis (Link) Schneider] were encapsulated in calcium alginate beads for germplasm exchange and distribution. A gelling matrix of 3 % sodium alginate and 100 mM calcium chloride was found most suitable for formation of ideal calcium alginate beads. Best response for shoot sprouting from encapsulated shoot tips was recorded on 0.8 % agar-solidified full-strength MS medium. Rooting was induced upon transfer of sprouted shoots to 0.8 % agar-solidified MS medium containing 1 mg l(-1) IBA. About 70 % of encapsulated shoot tips were rooted and converted into plantlets. Plants regenerated from encapsulated shoot tips were acclimatized successfully. The present encapsulation approach could also be applied as an alternative method of propagation of desirable elite genotype of jojoba.

  18. Formulation, stabilisation and encapsulation of bacteriophage for phage therapy.

    Science.gov (United States)

    Malik, Danish J; Sokolov, Ilya J; Vinner, Gurinder K; Mancuso, Francesco; Cinquerrui, Salvatore; Vladisavljevic, Goran T; Clokie, Martha R J; Garton, Natalie J; Stapley, Andrew G F; Kirpichnikova, Anna

    2017-11-01

    Against a backdrop of global antibiotic resistance and increasing awareness of the importance of the human microbiota, there has been resurgent interest in the potential use of bacteriophages for therapeutic purposes, known as phage therapy. A number of phage therapy phase I and II clinical trials have concluded, and shown phages don't present significant adverse safety concerns. These clinical trials used simple phage suspensions without any formulation and phage stability was of secondary concern. Phages have a limited stability in solution, and undergo a significant drop in phage titre during processing and storage which is unacceptable if phages are to become regulated pharmaceuticals, where stable dosage and well defined pharmacokinetics and pharmacodynamics are de rigueur. Animal studies have shown that the efficacy of phage therapy outcomes depend on the phage concentration (i.e. the dose) delivered at the site of infection, and their ability to target and kill bacteria, arresting bacterial growth and clearing the infection. In addition, in vitro and animal studies have shown the importance of using phage cocktails rather than single phage preparations to achieve better therapy outcomes. The in vivo reduction of phage concentration due to interactions with host antibodies or other clearance mechanisms may necessitate repeated dosing of phages, or sustained release approaches. Modelling of phage-bacterium population dynamics reinforces these points. Surprisingly little attention has been devoted to the effect of formulation on phage therapy outcomes, given the need for phage cocktails, where each phage within a cocktail may require significantly different formulation to retain a high enough infective dose. This review firstly looks at the clinical needs and challenges (informed through a review of key animal studies evaluating phage therapy) associated with treatment of acute and chronic infections and the drivers for phage encapsulation. An important driver

  19. The encapsulation of Magnox type fuel elements for extended storage in cooling ponds

    International Nuclear Information System (INIS)

    Baker, D.W.C.; Burt, G.A.

    1978-01-01

    A method of encapsulating spent fuel elements in a protective plastics medium to enable them to be stored for protracted periods under water, without risk of further significant corrosion, has been developed. It is visualised that the elements after discharge from the reactor would be allowed to cool under water for a period of at least 100 days and would then be encapsulated while remaining immersed. A suitable two pack system based on a solvent free epoxy resin cured with an aromatic amine adduct has been identified. The equipment and processes which have been developed for handling, conditioning and encapsulating the fuel are described. (author)

  20. CHARACTERIZING DOE HANFORD SITE WASTE ENCAPSULATION STORAGE FACILITY CELLS USING RADBALL

    Energy Technology Data Exchange (ETDEWEB)

    Farfan, E.; Coleman, R.

    2011-03-31

    RadBall{trademark} is a novel technology that can locate and quantify unknown radioactive hazards within contaminated areas, hot cells, and gloveboxes. The device consists of a colander-like outer tungsten collimator that houses a radiation-sensitive polymer semi-sphere. The collimator has a number of small holes with tungsten inserts; as a result, specific areas of the polymer are exposed to radiation becoming increasingly more opaque in proportion to the absorbed dose. The polymer semi-sphere is imaged in an optical computed tomography scanner that produces a high resolution 3D map of optical attenuation coefficients. A subsequent analysis of the optical attenuation data using a reverse ray tracing or backprojection technique provides information on the spatial distribution of gamma-ray sources in a given area forming a 3D characterization of the area of interest. RadBall{trademark} was originally designed for dry deployments and several tests, completed at Savannah River National Laboratory and Oak Ridge National Laboratory, substantiate its modeled capabilities. This study involves the investigation of the RadBall{trademark} technology during four submerged deployments in two water filled cells at the DOE Hanford Site's Waste Encapsulation Storage Facility.

  1. Some thermal analysis aspects of metal encapsulated waste

    International Nuclear Information System (INIS)

    Jardine, L.J.; Steindler, M.J.

    1978-01-01

    This paper is to summarize two waste management schemes: (1) packaging for extended storage of LWR spent fuel assemblies, with the capability for simple conversion either to terminal storage if a ''throwaway'' fuel cycle is ultimately adopted or to a form that can be reprocessed and (2) packaging for the terminal storage of solidified high-level wastes when the reprocessing of spent fuel is initiated. Only concepts utilizing metals or metal alloys to encapsulate either spent fuel or solidified high-level waste forms have been considered. Conceptual process flow sheets have been constructed to allow potential advantages and disadvantages of encapsulation alternatives to be identified in comparison with more conventional reference processes. Identification is also made of uncertainties of the analysis due to a lack of fundamental data required to perform evaluations. 3 tables

  2. Polyethylene encapsulation of mixed wastes: Scale-up feasibility

    International Nuclear Information System (INIS)

    Kalb, P.D.; Heiser, J.H.; Colombo, P.

    1991-01-01

    A polyethylene process for the improved encapsulation of radioactive, hazardous, and mixed wastes have been developed at Brookhaven National Laboratory (BNL). Improvements in waste loading and waste form performance have been demonstrated through bench-scale development and testing. Maximum waste loadings of up to 70 dry wt % mixed waste nitrate salt were achieved, compared with 13--20 dry wt % using conventional cement processes. Stability under anticipated storage and disposal conditions and compliance with applicable hazardous waste regulations were demonstrated through a series of lab-scale waste form performance tests. Full-scale demonstration of this process using actual or surrogate waste is currently planned. A scale-up feasibility test was successfully conducted, demonstrating the ability to process nitrate salts at production rates (up to 450 kg/hr) and the close agreement between bench- and full-scale process parameters. Cored samples from the resulting pilot-scale (114 liter) waste form were used to verify homogeneity and to provide additional specimens for confirmatory performance testing

  3. Bioactive Compounds And Encapsulation Of Yanang ( Tiliacora ...

    African Journals Online (AJOL)

    Furthermore, this paper reports the design of the experimental method for optimization of Yanang encapsulation using three independent variables: the ratio of core material (Yanang), to wall material (gum Arabic), gum Arabic concentration and inlet temperature of spray drying on bioactive compounds stability. The stability ...

  4. Encapsulating culture : European car travel 1900-1940

    NARCIS (Netherlands)

    Mom, G.P.A.

    2011-01-01

    This article analyzes the gradual encapsulation of motorists into a closed cocoon and the parallel domestication of a dominant masculine, aggressive subculture of the early automobile. It uncovers the existence of a specific French–Belgian group of (male) avant-garde artists who were at the same

  5. Effects of dissolving microneedle fabrication parameters on the activity of encapsulated lysozyme.

    Science.gov (United States)

    Fakhraei Lahiji, Shayan; Jang, Yoojung; Ma, Yonghao; Dangol, Manita; Yang, Huisuk; Jang, Mingyu; Jung, Hyungil

    2018-05-30

    Dissolving microneedle (DMN) is referred to a microscale needle that encapsulates drug(s) within a biodegradable polymer matrix and delivers it into the skin in a minimally invasive manner. Although vast majority of studies have emphasized DMN as an efficient drug delivery system, the activity of DMN-encapsulated proteins or antigens can be significantly affected due to a series of thermal, physical and chemical stress factors during DMN fabrication process and storage period. The objective of this study is to evaluate the effects of DMN fabrication parameters including polymer type, polymer concentration, fabrication and storage temperature, and drying conditions on the activity of the encapsulated therapeutic proteins by employing lysozyme (LYS) as a model protein. Our results indicate that a combination of low temperature fabrication, mild drying condition, specific polymer concentration, and addition of protein stabilizer can maintain the activity of encapsulated LYS up to 99.8 ± 3.8%. Overall, findings of this study highlight the importance of optimizing DMN fabrication parameters and paves way for the commercialization of an efficient delivery system for therapeutics. Copyright © 2018 Elsevier B.V. All rights reserved.

  6. Preparation, characterization, and in vitro release study of albendazole-encapsulated nanosize liposomes

    Science.gov (United States)

    Panwar, Preety; Pandey, Bhumika; Lakhera, P C; Singh, K P

    2010-01-01

    The purpose of the present study was to formulate effective and controlled release albendazole liposomal formulations. Albendazole, a hydrophobic drug used for the treatment of hydatid cysts, was encapsulated in nanosize liposomes. Rapid evaporation method was used for the preparation of albendazole-encapsulated conventional and PEGylated liposomes consisting of egg phosphatidylcholine (PC) and cholesterol (CH) in the molar ratios of (6:4) and PC:CH: polyethylene glycol (PEG) (5:4:1), respectively. In this study, PEGylated and conventional liposomes containing albendazole were prepared and their characteristics, such as particle size, encapsulation efficiency, and in vitro drug release were investigated. The drug encapsulation efficiency of PEGylated and conventional liposomes was 81% and 72%, respectively. The biophysical characterization of both conventional and PEG-coated liposomes were done by transmission electron microscopy and UV-vis spectrophotometry. Efforts were made to study in vitro release of albendazole. The drug release rate showed decrease in albendazole release in descending order: free albendazole, albendazole-loaded conventional liposomes, and least with albendazole-loaded PEG-liposomes. Biologically relevant vesicles were prepared and in vitro release of liposome-entrapped albendazole was determined. PMID:20309396

  7. Evaluation of the immunogenicity of liposome encapsulated HVR1 and NS3 regions of genotype 3 HCV, either singly or in combination

    Directory of Open Access Journals (Sweden)

    Gupte Gouri M

    2012-03-01

    Full Text Available Abstract Background Hepatitis C virus displays a high rate of mutation and exists as a quasispecies in infected patients. In the absence of an effective universal vaccine, genotype-specific vaccine development represents an alternative. We have attempted to develop a genotype 3 based, liposome encapsulated HCV vaccine with hypervariable region-1 (HVR1 and non-structural region-3 (NS3 components. Results HCV RNA extracted from serum samples of 49 chronically infected patients was PCR amplified to obtain HVR1 region. These amplified products were cloned to obtain 20 clones per sample in order to identify the quasispecies pattern. The HVR1 consensus sequence, along with three variants was reverse transcribed to obtain peptides. The peptides were checked for immunoreactivity individually, as a pool or as a single peptide tetramer interspersed with four glycine residues. Anti-HCV positivity varied from 42.6% (tetramer to 92.2% (variant-4 when 115 anti-HCV positive sera representing genotypes 1, 3, 4 and 6 were screened. All the 95 anti-HCV negatives were scored negative by all antigens. Mice were immunized with different liposome encapsulated or Al(OH3 adjuvanted formulations of HVR1 variants and recombinant NS3 protein, and monitored for anti-HVR1 and anti-NS3 antibody titres, IgG isotypes and antigen specific cytokine levels. A balanced Th1/Th2 isotyping response with high antibody titres was observed in most of the liposome encapsulated antigen groups. The effect of liposomes and aluminium hydroxide on the expression of immune response genes was studied using Taqman Low Density Array. Both Th1 (IFN-gamma, Il18 and Th2 (Il4 genes were up regulated in the liposome encapsulated HVR1 variant pool-NS3 combination group. In-vitro binding of the virus to anti-HVR1 antibodies was demonstrated. Conclusion The optimum immunogen was identified to be combination of peptides of HVR1 consensus sequence and its variants along with pNS3 encapsulated in liposomes

  8. PEGylated lipid nanocapsules with improved drug encapsulation and controlled release properties.

    Science.gov (United States)

    Hervella, Pablo; Alonso-Sande, Maria; Ledo, Francisco; Lucero, Maria L; Alonso, Maria J; Garcia-Fuentes, Marcos

    2014-01-01

    Drugs with poor lipid and water solubility are some of the most challenging to formulate in nanocarriers, typically resulting in low encapsulation efficiencies and uncontrolled release profiles. PEGylated nanocapsules (PEG-NC) are known for their amenability to diverse modifications that allow the formation of domains with different physicochemical properties, an interesting feature to address a drug encapsulation problem. We explored this problem by encapsulating in PEG-NC the promising anticancer drug candidate F10320GD1, used herein as a model for compounds with such characteristics. The nanocarriers were prepared from Miglyol(®), lecithin and PEG-sterate through a solvent displacement technique. The resulting system was a homogeneous suspension of particles with size around 200 nm. F10320GD1 encapsulation was found to be very poor (<15%) if PEG-NC were prepared using water as continuous phase; but we were able to improve this value to 85% by fixing the pH of the continuous phase to 9. Interestingly, this modification also improved the controlled release properties and the chemical stability of the formulation during storage. These differences in pharmaceutical properties together with physicochemical data suggest that the pH of the continuous phase used for PEG-NC preparation can modify drug allocation, from the external shell towards the inner lipid core of the nanocapsules. Finally, we tested the bioactivity of the drug-loaded PEG-NC in several tumor cell lines, and also in endothelial cells. The results indicated that drug encapsulation led to an improvement on drug cytotoxicity in tumor cells, but not in non-tumor endothelial cells. Altogether, the data confirms that PEG-NC show adequate delivery properties for F10320GD1, and underlines its possible utility as an anticancer therapy.

  9. New trends in encapsulation of liposoluble vitamins.

    Science.gov (United States)

    Gonnet, M; Lethuaut, L; Boury, F

    2010-09-15

    Liposoluble vitamins (A, D, E, and K) and carotenoids have many benefits on health. They are provided mainly by foods. At pharmacological doses, they can also be used to treat skin diseases, several types of cancer or decrease oxidative stress. These molecules are sensitive to oxidation, thus encapsulation might constitute an appropriate mean to preserve their properties during storage and enhance their physiological potencies. Formulation processes have been adapted for sensitive molecule, limiting their exposure to high temperature, light or oxygen. Each administration pathway, oral, systemic, topical, transdermal and local, requires different particle sizes and release profile. Encapsulation can lead to greater efficiency allowing smaller administration doses thus diminishing potential hypervitaminosis syndrome appearance and side effects. Carrier formulation can be based on vitamin dissolution in lipid media and its stabilization by surfactant mixture, on its entrapment in a matrix or molecular system. Suitability of each type of carrier will be discussed for each pathway. 2010 Elsevier B.V. All rights reserved.

  10. Encapsulated nanoepigallocatechin-3-gallate and elemental selenium nanoparticles as paradigms for nanochemoprevention

    Directory of Open Access Journals (Sweden)

    Wang D

    2012-03-01

    Full Text Available Dongxu Wang1, Ethan Will Taylor2, Yijun Wang1, Xiaochun Wan1, Jinsong Zhang11Key Laboratory of Tea Biochemistry and Biotechnology, School of Tea and Food Science, Anhui Agricultural University, Hefei, Anhui, People’s Republic of China; 2Department of Nanoscience, Joint School of Nanoscience and Nanoengineering, University of North Carolina at Greensboro, Greensboro, NC, USAAbstract: Chemoprevention that impedes one or more steps in carcinogenesis, via long-term administration of naturally occurring or synthetic compounds, is widely considered to be a crucial strategy for cancer control. Selenium (Se has chemopreventive effects, but its application is limited due to a low therapeutic index as shown in numerous animal experiments. In contrast to Se, which was known for its toxicity prior to the discovery of its beneficial effects, the natural compound epigallocatechin-3-gallate (EGCG was originally considered to be nontoxic. Due to its preventive effects on many types of cancer in various animal models, EGCG has been regarded as a prime example of a promising chemopreventive agent without major toxicity concerns. However, very recently, evidence has accumulated showing that efficacious doses of EGCG used in health promotion may not be far from its toxic dose level. Therefore, both Se and EGCG need to be modified by novel pharmaceutical technologies to attain enhanced efficacy and/or reduced toxicity. Nanotechnology may be one of these technologies. In support of this hypothesis, the characteristics of polylactic acid and polyethylene glycol-encapsulated nano-EGCG and elemental Se nanoparticles dispersed by bovine serum albumin are reviewed in this article. Encapsulation of EGCG to form nano-EGCG leads to its enhanced stability in plasma and remarkably superior chemopreventive effects, with more than tenfold dose advantages in inducing apoptosis and inhibition of both angiogenesis and tumor growth. Se at nanoparticle size (“Nano-Se”, compared

  11. Encapsulation of thermal energy storage media

    Science.gov (United States)

    Dhau, Jaspreet; Goswami, Dharendra; Jotshi, Chand K.; Stefanakos, Elias K.

    2017-09-19

    In one embodiment, a phase change material is encapsulated by forming a phase change material pellet, coating the pellet with flexible material, heating the coated pellet to melt the phase change material, wherein the phase change materials expands and air within the pellet diffuses out through the flexible material, and cooling the coated pellet to solidify the phase change material.

  12. A Robust Oil-in-Oil Emulsion for the Nonaqueous Encapsulation of Hydrophilic Payloads.

    Science.gov (United States)

    Lu, Xiaocun; Katz, Joshua S; Schmitt, Adam K; Moore, Jeffrey S

    2018-03-14

    encapsulation technology is applicable to other hydrophilic payloads such as polyols, aromatic amines, and aromatic heterocyclic bases. Such payloads are important for the development of extended pot or shelf life systems and responsive coatings that report, protect, modify, and heal themselves without intervention.

  13. Evaluation of antinociceptive activity of nanoliposome-encapsulated and free-form diclofenac in rats and mice

    Directory of Open Access Journals (Sweden)

    Goh JZ

    2014-12-01

    Full Text Available Jun Zheng Goh,1 Sook Nai Tang,1 Hoe Siong Chiong,1,2 Yoke Keong Yong,3 Ahmad Zuraini,1 Muhammad Nazrul Hakim1,4 1Department of Biomedical Sciences, Universiti Putra Malaysia, Serdang, Selangor, Malaysia; 2InQpharm Group, Kuala Lumpur, Malaysia; 3Department of Human Anatomy, 4Halal Product Research Institute, Universiti Putra Malaysia, Serdang, Selangor, Malaysia Abstract: Diclofenac is a nonsteroidal anti-inflammatory drug (NSAID that exhibits anti-inflammatory, antinociceptive, and antipyretic activities. Liposomes have been shown to improve the therapeutic efficacy of encapsulated drugs. The present study was conducted to compare the antinociceptive properties between liposome-encapsulated and free-form diclofenac in vivo via different nociceptive assay models. Liposome-encapsulated diclofenac was prepared using the commercialized proliposome method. Antinociceptive effects of liposome-encapsulated and free-form diclofenac were evaluated using formalin test, acetic acid-induced abdominal writhing test, Randall–Selitto paw pressure test, and plantar test. The results of the writhing test showed a significant reduction of abdominal constriction in all treatment groups in a dose-dependent manner. The 20 mg/kg liposome-encapsulated diclofenac demonstrated the highest antinociceptive effect at 78.97% compared with 55.89% in the free-form group at equivalent dosage. Both liposome-encapsulated and free-form diclofenac produced significant results in the late phase of formalin assay at a dose of 20 mg/kg, with antinociception percentages of 78.84% and 60.71%, respectively. Significant results of antinociception were also observed in both hyperalgesia assays. For Randall–Sellito assay, the highest antinociception effect of 71.38% was achieved with 20 mg/kg liposome-encapsulated diclofenac, while the lowest antinociceptive effect of 17.32% was recorded with 0 mg/kg liposome formulation, whereas in the plantar test, the highest antinociceptive effect

  14. [Mass spectrometry technology and its application in analysis of biological samples].

    Science.gov (United States)

    Zhao, Long-Shan; Li, Qing; Guo, Chao-Wei; Chen, Xiao-Hui; Bi, Kai-Shun

    2012-02-01

    With the excellent merits of wide analytical range, high sensitivity, small sample size, fast analysis speed, good repeatability, simple operation, low mobile phase consumption, as well as its capability of simultaneous isolation and identification, etc, mass spectrometry techniques have become widely used in the area of environmental science, energy chemical industry, biological medicine, and so on. This article reviews the application of mass spectrometry technology in biological sample analysis in the latest three years with the focus on the new applications in pharmacokinetics and bioequivalence, toxicokinetics, pharmacokinetic-pharmacodynamic, population pharmacokinetics, identification and fragmentation pathways of drugs and their metabolites and metabonomics to provide references for further study of biological sample analysis.

  15. Space science technology: In-situ science. Sample Acquisition, Analysis, and Preservation Project summary

    Science.gov (United States)

    Aaron, Kim

    1991-01-01

    The Sample Acquisition, Analysis, and Preservation Project is summarized in outline and graphic form. The objective of the project is to develop component and system level technology to enable the unmanned collection, analysis and preservation of physical, chemical and mineralogical data from the surface of planetary bodies. Technology needs and challenges are identified and specific objectives are described.

  16. Sol-gel encapsulation for controlled drug release and biosensing

    Science.gov (United States)

    Fang, Jonathan

    The main focus of this dissertation is to investigate the use of sol-gel encapsulation of biomolecules for controlled drug release and biosensing. Controlled drug release has advantages over conventional therapies in that it maintains a constant, therapeutic drug level in the body for prolonged periods of time. The anti-hypertensive drug Captopril was encapsulated in sol-gel materials of various forms, such as silica xerogels and nanoparticles. The primary objective was to show that sol-gel silica materials are promising drug carriers for controlled release by releasing Captopril at a release rate that is within a therapeutic range. We were able to demonstrate desired release for over a week from Captopril-doped silica xerogels and overall release from Captopril-doped silica nanoparticles. As an aside, the antibiotic Vancomycin was also encapsulated in these porous silica nanoparticles and desired release was obtained for several days in-vitro. The second part of the dissertation focuses on immobilizing antibodies and proteins in sol-gel to detect various analytes, such as hormones and amino acids. Sol-gel competitive immunoassays on antibody-doped silica xerogels were used for hormone detection. Calibration for insulin and C-peptide in standard solutions was obtained in the nM range. In addition, NASA-Ames is also interested in developing a reagentless biosensor using bacterial periplasmic binding proteins (bPBPs) to detect specific biomarkers, such as amino acids and phosphate. These bPBPs were doubly labeled with two different fluorophores and encapsulated in silica xerogels. Ligand-binding experiments were performed on the bPBPs in solution and in sol-gel. Ligand-binding was monitored by fluorescence resonance energy transfer (FRET) between the two fluorophores on the bPBP. Titration data show that one bPBP has retained its ligand-binding properties in sol-gel.

  17. Synthesis of nanoporous carbohydrate metal-organic framework and encapsulation of acetaldehyde

    Science.gov (United States)

    Al-Ghamdi, Saleh; Kathuria, Ajay; Abiad, Mohamad; Auras, Rafael

    2016-10-01

    Gamma cyclodextrin (γ-CD) metal organic frameworks (CDMOFs) were synthesized by coordinating γ-CDs with potassium hydroxide (KOH), referred hereafter as CDMOF-a, and potassium benzoate (C7H5KO2), denoted as CDMOF-b. The obtained CDMOF structures were characterized using nitrogen sorption isotherm, thermo-gravimetric analysis (TGA), X-ray diffraction (XRD), and scanning electron microscopy (SEM). High surface areas were achieved by the γ-CD based MOF structures where the Langmuir specific surface areas (SSA) of CDMOF-a and CDMOF-b were determined as 1376 m2 g-1 and 607 m2 g-1; respectively. The dehydrated CDMOF structures demonstrated good thermal stability up to 250 °C as observed by the TGA studies. XRD results for CDMOF-a and CDMOF-b reveal a body centered-cubic (BCC) and trigonal crystal system; respectively. Due to its accessible porous structure and high surface area, acetaldehyde was successfully encapsulated in CDMOF-b. During the release kinetic studies, we observed peak release of 53 μg of acetaldehyde per g of CDMOF-b, which was 100 times greater than previously reported encapsulation in β-CD. However, aldol condensation reaction occurred during encapsulation of acetaldehyde into CDMOF-a. This research work demonstrates the potential to encapsulate volatile organic compounds in CDMOF-b, and their associated release for applications including food, pharmaceuticals and packaging.

  18. Comparison of modified sulfur cement and hydraulic cement for encapsulation of radioactive and mixed wastes

    International Nuclear Information System (INIS)

    Kalb, P.D.; Heiser, J.H. III; Colombo, P.

    1990-01-01

    The majority of solidification/stabilization systems for low-level radioactive waste (LLW) and mixed waste, both in the commercial sector and at Department of Energy (DOE) facilities, utilize hydraulic cement (such as portland cement) to encapsulate waste materials and yield a monolithic solid waste form for disposal. Because hydraulic cement requires a chemical hydration reaction for setting and hardening, it is subject to potential interactions between elements in the waste and binder that can retard or prevent solidification. A new and innovative process utilizing modified sulfur cement developed by the US Bureau of Mines has been applied at Brookhaven National Laboratory (BNL) for the encapsulation of many of these problem wastes. Modified sulfur cement is a thermoplastic material, and as such, it can be heated above its melting point, combined with dry waste products to form a homogeneous mixture, and cooled to form a monolithic solid product. Under sponsorship of the DOE, research and development efforts at BNL have successfully applied the modified sulfur cement process for treatment of a range of LLWs including sodium sulfate salts, boric acid salts, and incinerator bottom ash and for mixed waste contaminated incinerator fly ash. Process development studies were conducted to determine optimal waste loadings for each waste type. Property evaluation studies were conducted to test waste form behavior under disposal conditions by applying relevant performance testing criteria established by the Nuclear Regulatory Commission (for LLW) and the Environmental Protection Agency (for hazardous wastes). Based on both processing and performance considerations, significantly greater waste loadings were achieved using modified sulfur cement when compared with hydraulic cement. Technology demonstration of the modified sulfur cement encapsulation system using production-scale equipment is scheduled for FY 1991

  19. Encapsulation of curcumin in polyelectrolyte nanocapsules and their neuroprotective activity

    Science.gov (United States)

    Szczepanowicz, Krzysztof; Jantas, Danuta; Piotrowski, Marek; Staroń, Jakub; Leśkiewicz, Monika; Regulska, Magdalena; Lasoń, Władysław; Warszyński, Piotr

    2016-09-01

    Poor water solubility and low bioavailability of lipophilic drugs can be potentially improved with the use of delivery systems. In this study, encapsulation of nanoemulsion droplets was utilized to prepare curcumin nanocarriers. Nanosize droplets containing the drug were encapsulated in polyelectrolyte shells formed by the layer-by-layer (LbL) adsorption of biocompatible polyelectrolytes: poly-L-lysine (PLL) and poly-L-glutamic acid (PGA). The size of synthesized nanocapsules was around 100 nm. Their biocompatibility and neuroprotective effects were evaluated on the SH-SY5Y human neuroblastoma cell line using cell viability/toxicity assays (MTT reduction, LDH release). Statistically significant toxic effect was clearly observed for PLL coated nanocapsules (reduction in cell viability about 20%-60%), while nanocapsules with PLL/PGA coating did not evoke any detrimental effects on SH-SY5Y cells. Curcumin encapsulated in PLL/PGA showed similar neuroprotective activity against hydrogen peroxide (H2O2)-induced cell damage, as did 5 μM curcumin pre-dissolved in DMSO (about 16% of protection). Determination of concentration of curcumin in cell lysate confirmed that curcumin in nanocapsules has cell protective effect in lower concentrations (at least 20 times) than when given alone. Intracellular mechanisms of encapsulated curcumin-mediated protection engaged the prevention of the H2O2-induced decrease in mitochondrial membrane potential (MMP) but did not attenuate Reactive Oxygen Species (ROS) formation. The obtained results indicate the utility of PLL/PGA shell nanocapsules as a promising, alternative way of curcumin delivery for neuroprotective purposes with improved efficiency and reduced toxicity.

  20. Preparation of encapsulated proteins dissolved in low viscosity fluids

    International Nuclear Information System (INIS)

    Ehrhardt, Mark R.; Flynn, Peter F.; Wand, A. Joshua

    1999-01-01

    The majority of proteins are too large to be comprehensively examined by solution NMR methods, primarily because they tumble too slowly in solution. One potential approach to making the NMR relaxation properties of large proteins amenable to modern solution NMR techniques is to encapsulate them in a reverse micelle which is dissolved in a low viscosity fluid. Unfortunately, promising low viscosity fluids such as the short chain alkanes, supercritical carbon dioxide, and various halocarbon refrigerants all require the application of significant pressure to be kept liquefied at room temperature. Here we describe the design and use of a simple cost effective NMR tube suitable for the preparation of solutions of proteins encapsulated in reverse micelles dissolved in such fluids

  1. Design of bioartificial pancreas with functional micro/nano-based encapsulation of islets.

    Science.gov (United States)

    Kepsutlu, Burcu; Nazli, Caner; Bal, Tugba; Kizilel, Seda

    2014-01-01

    Type I diabetes mellitus (TIDM), a devastating health issue in all over the world, has been treated by successful transplantation of insulin secreting pancreatic islets. However, serious limitations such as the requirement of immunosuppressive drugs for recipient patients, side effects as a result of long-term use of drugs, and reduced functionality of islets at the transplantation site remain. Bioartificial pancreas that includes islets encapsulated within semi-permeable membrane has been considered as a promising approach to address these requirements. Many studies have focused on micro or nanobased islet immunoisolation systems and tested the efficacy of encapsulated islets using in vitro and in vivo platforms. In this review, we address current progress and obstacles for the development of a bioartificial pancreas using micro/nanobased systems for encapsulation of islets.

  2. Comparison of three artificial digestion methods for detection of non-encapsulated Trichinella pseudospiralis larvae in pork

    DEFF Research Database (Denmark)

    Nockler, K.; Reckinger, S.; Szabo, I.

    2009-01-01

    In a ring trial involving five laboratories (A, B, C, D, and E), three different methods of artificial digestion were compared for the detection of non-encapsulated Trichinella pseudospiralis larvae in minced meat. Each sample panel consisted often 1 g minced pork samples. All samples in each panel...... were derived from a bulk meat preparation with a nominal value of either 7 or 17 larvae per g (Ipg). Samples were tested for the number of muscle larvae using the magnetic stirrer method (labs A, B, and E), stomacher method (lab B), and Trichomatic 35 (R) (labs C and D). T. pseudospiralis larvae were...... by using the magnetic stirrer method (22%), followed by the stomacher method (25%), and Trichomatic 35 (R) (30%). Results revealed that T. pseudospiralis larvae in samples with a nominal value of 7 and 17 Ipg can be detected by all three methods of artificial digestion....

  3. Uranium metal oxidation, grinding, and encapsulation in BorobondR: TRU waste management - 59279

    International Nuclear Information System (INIS)

    Cook, Kevin S.; Addington, Larry A.; Utley, Beth

    2012-01-01

    Hydrogen generation mitigation for K Basin sludge was examined by encapsulation of uranium metal in BoroBond R , pre-oxidation of uranium metal with Fenton's reagent and grinding of Densalloy SD170, an irradiated uranium metal surrogate. Encapsulation in BoroBond R resulted in pressure increase rates at 60 deg. C ranging from 0.116 torr/h to 0.186 torr/h compared to 0.240 torr/h for a uranium metal in water standard. Samples cast with higher water content led to increased rates. A Fenton's reagent system consisting of a simple reagent mix of FeSO 4 .7H 2 O, H 2 O 2 and HCl effectively oxidized 1/4'' cubes of uranium metal in under four days at room temperature. Increased peroxide addition rate, increased FeSO 4 .7H 2 O concentration and low pH all increase the corrosion rate. Densalloy SD170 with an average particle size of 581 μm with 7.63 % of particles less than 90 μm was milled so that over 90 % of the Densalloy mass measured less than 90 μm in 6 hours of milling. Acceptable wear rates were seen on wear components that were from standard materials (Nitronic SS and 440SS). (authors)

  4. Dispensing of very low volumes of ultra high viscosity alginate gels: a new tool for encapsulation of adherent cells and rapid prototyping of scaffolds and implants.

    Science.gov (United States)

    Gepp, Michael M; Ehrhart, Friederike; Shirley, Stephen G; Howitz, Steffen; Zimmermann, Heiko

    2009-01-01

    We present a tool for dispensing very low volumes (20 nL or more) of ultra high viscosity (UHV) medical-grade alginate hydrogels. It uses a modified piezo-driven micrometering valve, integrated into a versatile system that allows fast prototyping of encapsulation procedures and scaffold production. Valves show excellent dispensing properties for UHV alginate in concentrations of 0.4% and 0.7% and also for aqueous liquids. An optimized process flow provides excellent handling of biological samples under sterile conditions. This technique allows the encapsulation of adherent cells and structuring of substrates for biotechnology and regenerative medicine. A variety of cell lines showed at least 70% viability after encapsulation (including cell lines that are relevant in regenerative medicine like Hep G2), and time-lapse analysis revealed cells proliferating and showing limited motility under alginate spots. Cells show metabolic activity, gene product expression, and physiological function. Encapsulated cells have contact with the substrate and can exchange metabolites while being isolated from macromolecules in the environment. Contactless dispensing allows structuring of substrates with alginate, isolation and transfer of cell-alginate complexes, and the dispensing of biological active hydrogels like extracellular matrix-derived gels.

  5. Liposomal encapsulated Zn-DTPA for removing intracellular 169Yb

    International Nuclear Information System (INIS)

    Blank, M.L.; Cress, E.A.; Byrd, B.L.; Washburn, L.C.; Snyder, F.

    1980-01-01

    Multilamellar liposomes possessing neutral positive or negative charges were tested for their capacity to encapsulate sodium ethylenediaminetetraacetate (EDTA) and for their selectivity in depositing in specific tissues after being injected into rats. Negative-charged liposomes had the greatest trapping efficiency over a wide range of lipid-to-aqueous phase ratios. In contrast, except for lung, liposomal charge had no significant effect on the tissue distribution of encapsulated EDTA; liver and spleen exhibited the highest uptake with all preparations. The proportion of encapsulated EDTA taken up by the liver decreased as the amount of injected liposomes was increased. Free zinc diethylenetriaminepentaacetate (Zn-DTPA) and multilamellar liposomes containing entrapped Zn-DTPA were administered to rats that had been injected with 169 Yb-citrate 24 hr earlier. At doses of 14 mg Zn-DTPA per kg body weight, both free Zn-DPTA and the liposomal-bound Zn-DTPA caused increased removal of 169 Yb from the animals. However, treatment with the liposomal Zn-DTPA caused significantly more of the 169 Yb to be removed than did the free Zn-DTPA treatment by itself. Our data indicate that lipophilic forms of chelators can effectively increase the removal rates of heavy metal contamination in tissues. (author)

  6. Biological applications of zinc imidazole framework through protein encapsulation

    Directory of Open Access Journals (Sweden)

    Pawan Kumar

    2015-12-01

    Full Text Available Abstract The robustness of biomolecules is always a significant challenge in the application of biostorage in biotechnology or pharmaceutical research. To learn more about biostorage in porous materials, we investigated the feasibility of using zeolite imidazolate framework (ZIF-8 with respect to protein encapsulation. Here, bovine serum albumin (BSA was selected as a model protein for encapsulation with the synthesis of ZIF-8 using water as a media. ZIF-8 exhibited excellent protein adsorption capacity through successive adsorption of free BSA with the formation of hollow crystals. The loading of protein in ZIF-8 crystals is affected by the molecular weight due to diffusion-limited permeation inside the crystals and also by the affinity of the protein to the pendent group on the ZIF-8 surface. The polar nature of BSA not only supported adsorption on the solid surface, but also enhanced the affinity of crystal spheres through weak coordination interactions with the ZIF-8 framework. The novel approach tested in this study was therefore successful in achieving protein encapsulation with porous, biocompatible, and decomposable microcrystalline ZIF-8. The presence of both BSA and FITC–BSA in ZIF-8 was confirmed consistently by spectroscopy as well as optical and electron microscopy.

  7. Exergy analysis of encapsulation of photochromic dye by spray drying

    Science.gov (United States)

    Çay, A.; Akçakoca Kumbasar, E. P.; Morsunbul, S.

    2017-10-01

    Application of exergy analysis methodology for encapsulation of photochromic dyes by spray drying was presented. Spray drying system was investigated considering two subsystems, the heater and the dryer sections. Exergy models for each subsystem were proposed and exergy destruction rate and exergy efficiency of each subsystem and the whole system were computed. Energy and exergy efficiency of the system were calculated to be 5.28% and 3.40%, respectively. It was found that 90% of the total exergy inlet was destroyed during encapsulation by spray drying and the exergy destruction of the heater was found to be higher.

  8. Aerosolized liposomes with dipalmitoyl phosphatidylcholine enhance pulmonary absorption of encapsulated insulin compared with co-administered insulin.

    Science.gov (United States)

    Chono, Sumio; Togami, Kohei; Itagaki, Shirou

    2017-11-01

    We have previously shown that aerosolized liposomes with dipalmitoyl phosphatidylcholine (DPPC) enhance the pulmonary absorption of encapsulated insulin. In this study, we aimed to compare insulin encapsulated into the liposomes versus co-administration of empty liposomes and unencapsulated free insulin, where the DPCC liposomes would serve as absorption enhancer. The present study provides the useful information for development of noninvasive treatment of diabetes. Co-administration of empty DPPC liposomes and unencapsulated free insulin was investigated in vivo to assess the potential enhancement in protein pulmonary absorption. Co-administration was compared to DPPC liposomes encapsulating insulin, and free insulin. DPPC liposomes enhanced the pulmonary absorption of unencapsulated free insulin; however, the enhancing effect was lower than that of the DPPC liposomes encapsulating insulin. The mechanism of the pulmonary absorption of unencapsulated free insulin by DPPC liposomes involved the opening of epithelial cell space in alveolar mucosa, and not mucosal cell damage, similar to that of the DPPC liposomes encapsulating insulin. In an in vitro stability test, insulin in the alveolar mucus layer that covers epithelial cells was stable. These findings suggest that, although unencapsulated free insulin spreads throughout the alveolar mucus layer, the concentration of insulin released near the absorption surface is increased by the encapsulation of insulin into DPPC liposomes and the absorption efficiency is also increased. We revealed that the encapsulation of insulin into DPPC liposomes is more effective for pulmonary insulin absorption than co-administration of DPPC liposomes and unencapsulated free insulin.

  9. On the constraints of encapsulated knowledge : Clinical case representations by medical experts and subexperts

    NARCIS (Netherlands)

    Rikers, Remy MJP; Schmidt, Henk G; Boshuizen, Henny PA

    2002-01-01

    This article is concerned with the role of so-called encapsulated knowledge and biomedical knowledge in the process of diagnosing clinical cases within and outside the medical specialist's domain of expertise. Based on the theory of knowledge encapsulation, we predicted that subexperts (i.e.,

  10. Single-step generation of fluorophore-encapsulated gold nanoparticle core-shell materials

    International Nuclear Information System (INIS)

    Sardar, R; Shem, P M; Pecchia-Bekkum, C; Bjorge, N S; Shumaker-Parry, J S

    2010-01-01

    We report a simple route to produce fluorophore-encapsulated gold nanoparticles (AuNPs) in a single step under aqueous conditions using the fluorophore 1-pyrenemethylamine (PMA). Different amounts of PMA were used and the resulting core-shell gold nanoparticles were analyzed using UV-visible absorption spectroscopy, fluorescence spectroscopy, and transmission and scanning electron microscopy. Electron microscopy analysis shows nanoparticles consisting of a gold nanoparticle core which is encapsulated with a lower contrast shell. In the UV-visible spectra, we observed a significant red shift (37 nm) of the localized surface plasmon resonance (LSPR) absorption maximum (λ max ) compared to citrate-stabilized AuNPs of a similar size. We attribute the prominent LSPR wavelength shift for PMA-AuNP conjugates to the increase in the local dielectric environment near the gold nanoparticles due to the shell formation. This simple, aqueous-based synthesis is a new approach to the production of fluorophore-encapsulated AuNPs that could be applicable in biological sensing systems and photonic device fabrication.

  11. Use of Red Cactus Pear (Opuntia ficus-indica Encapsulated Powder to Pigment Extruded Cereal

    Directory of Open Access Journals (Sweden)

    Martha G. Ruiz-Gutiérrez

    2017-01-01

    Full Text Available Encapsulated powder of the red cactus pear is a potential natural dye for the food industry and a known antioxidant. Although the use of this powder is possible, it is not clear how it alters food properties, thus ensuing commercial acceptability. The aim of this study was to evaluate the effect of encapsulated powder of the red cactus pear on the physicochemical properties of extruded cereals. The powder was mixed (2.5, 5.0, and 7.5% w/w with maize grits and extruded (mix moisture 22%, temperature 100°C, and screw speed 325 rpm. The physical, chemical, and sensory characteristics of the extruded cereal were evaluated; extruded cereal without encapsulated powder was used as a control. All cereal extrudates pigmented with the encapsulated powder showed statistically significant differences (P<0.05 in expansion, water absorption, color, density, and texture compared to the control. The encapsulated powder had a positive effect on expansion and water absorption indices, as well as color parameters, but a negative effect on density and texture. Extruded cereal properties were significantly (P<0.05 correlated. Sensorially, consumers accepted the extruded cereal with a lower red cactus pear powder content (2.5% w/w, because this presented characteristics similar to extruded cereal lacking pigment.

  12. Waste encapsulation and storage facility function analysis report

    International Nuclear Information System (INIS)

    Lund, D.P.

    1995-09-01

    The document contains the functions, function definitions, function interfaces, function interface definitions, Input Computer Automated Manufacturing Definition (IDEFO) diagrams, and a function hierarchy chart that describe what needs to be performed to deactivate Waste Encapsulation and Storage Facility (WESF)

  13. Optical encoding of microbeads based on silica particle encapsulated quantum dots and its applications

    Energy Technology Data Exchange (ETDEWEB)

    Zhu Xiaoxia; Cao Yuancheng; Jin Xin; Yang Jie; Hua Xiaofeng; Wang Haiqiao; Liu Bo; Wang Zhan; Wang Jianhao; Yang Liang; Zhao Yuandi [Key Laboratory of Biomedical Photonics of Ministry of Education-Wuhan National Laboratory for Optoelectronics, Huazhong University of Science and Technology, Wuhan, HuBei 430074 (China); Hubei Bioinformatics and Molecular Imaging Key Laboratory, College of Life Science and Technology, Huazhong University of Science and Technology, Wuhan, HuBei, 430074 (China)

    2008-01-16

    A novel method concerning the coding technology of polystyrene beads with Si encapsulated quantum dot (QD) particles (Si - QDs particles) is studied in this paper. In the reverse microemulsion system containing tetraethoxysilane (TEOS), water-soluble QDs (emission peak at 600 nm) were enveloped within the silica shell, forming Si - QDs particles. The Si - QDs particles were characterized by TEM, showing good uniform size, with an average diameter of about 167.0 nm. In comparison with the pure water-soluble QDs, the encapsulation of water-soluble QDs in the silica shell led to an enhancement in anti-photobleaching by providing inert barriers for the QDs. Images presented by SEM and confocal laser scanning microscopy demonstrated that the Si - QDs particles were equably coated on the surface of carboxyl functionalized polystyrene (PS) beads. Then, with the assistance of ethyl-3-(dimethyl aminopropyl) carbodiimide/N-hydroxysuccinimide (EDC/NHS), human IgG could be successfully crosslinked to Si - QDs particle coated PS-COOH beads. Furthermore, the Si - QDs coated PS-COOH beads with human IgG were examined in immunoassay experiments, and the results indicated that these beads could be applied in the specific recognition of goat-anti-human IgG in solution. This investigation is expected to provide a new route to bead coding in the field of suspension microarrays, based on the use of QDs.

  14. Charge effect of a liposomal delivery system encapsulating simvastatin to treat experimental ischemic stroke in rats

    Directory of Open Access Journals (Sweden)

    Campos-Martorell M

    2016-06-01

    Full Text Available Mireia Campos-Martorell,1 Mary Cano-Sarabia,2 Alba Simats,1 Mar Hernández-Guillamon,1 Anna Rosell,1 Daniel Maspoch,2,3 Joan Montaner1,4 1Neurovascular Research Laboratory, Institut de Recerca Vall d’Hebron, Universitat Autònoma de Barcelona, Barcelona, 2Catalan Institute of Nanoscience and Nanotechnology (ICN2, CSIC and The Barcelona Institute of Science and Technology, Universitat Autònoma de Barcelona, Barcelona, 3Institució Catalana de Recerca i Estudis Avançats (ICREA, 4Neurovascular Unit, Department of Neurology, Universitat Autònoma de Barcelona, Hospital Vall d’Hebron, Barcelona, Spain Background and aims: Although the beneficial effects of statins on stroke have been widely demonstrated both in experimental studies and in clinical trials, the aim of this study is to prepare and characterize a new liposomal delivery system that encapsulates simvastatin to improve its delivery into the brain. Materials and methods: In order to select the optimal liposome lipid composition with the highest capacity to reach the brain, male Wistar rats were submitted to sham or transitory middle cerebral arterial occlusion (MCAOt surgery and treated (intravenous [IV] with fluorescent-labeled liposomes with different net surface charges. Ninety minutes after the administration of liposomes, the brain, blood, liver, lungs, spleen, and kidneys were evaluated ex vivo using the Xenogen IVIS® Spectrum imaging system to detect the load of fluorescent liposomes. In a second substudy, simvastatin was assessed upon reaching the brain, comparing free and encapsulated simvastatin (IV administration. For this purpose, simvastatin levels in brain homogenates from sham or MCAOt rats at 2 hours or 4 hours after receiving the treatment were detected through ultra-high-protein liquid chromatography. Results: Whereas positively charged liposomes were not detected in brain or plasma 90 minutes after their administration, neutral and negatively charged liposomes

  15. Use of Electrohydrodynamic Processing for Encapsulation of Sensitive Bioactive Compounds and Applications in Food

    DEFF Research Database (Denmark)

    Jacobsen, Charlotte; García Moreno, Pedro Jesús; Mendes, Ana Carina Loureiro

    2018-01-01

    or in the gastrointestinal tract. For that purpose, efficient encapsulation of the compounds may be required. Spray drying is one of the most commonly used encapsulation techniques in the food industry, but it uses high temperature, which can lead to decomposition of the bioactive compounds. Recently, alternative...

  16. β-Glucan as an encapsulating agent: Effect on probiotic survival in simulated gastrointestinal tract.

    Science.gov (United States)

    Shah, Asima; Gani, Adil; Ahmad, Mudasir; Ashwar, Bilal Ahmad; Masoodi, F A

    2016-01-01

    Three strains of probiotics Lactobacillus casei, Lactobacillus brevis, and Lactobacillus plantarum were encapsulated in β-glucan matrix using emulsion technique. Further the encapsulated cells were studied for their tolerance in simulated gastrointestinal conditions and its storage stability. The average encapsulation efficiency of β-glucan-probiotic beads was found to be 74.01%. The surface morphology of β-glucan containing bacteria was studied using SEM. The noteworthy absorptions in the FT-IR spectra between 1300-900 cm(-1) and 2918-2925 cm(-1) corresponds to the presence of bacteria into the glucan matrix. Also, the thermal stability of β-glucan was evaluated using Differential Scanning Calorimeter. The efficiency of β-glucan in protecting the surviability of probiotic cells under simulated gastrointestinal conditions was studied. Results revealed significant (p<0.05) improvement to tolerance when the encapsulated cells were subjected to stresses like low pH, heat treatment, simulated intestinal conditions and storage. Copyright © 2015 Elsevier B.V. All rights reserved.

  17. Encapsulation and covalent binding of molecular payload in enzymatically activated micellar nanocarriers.

    Science.gov (United States)

    Rosenbaum, Ido; Harnoy, Assaf J; Tirosh, Einat; Buzhor, Marina; Segal, Merav; Frid, Liat; Shaharabani, Rona; Avinery, Ram; Beck, Roy; Amir, Roey J

    2015-02-18

    The high selectivity and often-observed overexpression of specific disease-associated enzymes make them extremely attractive for triggering the release of hydrophobic drug or probe molecules from stimuli-responsive micellar nanocarriers. Here we utilized highly modular amphiphilic polymeric hybrids, composed of a linear hydrophilic polyethylene glycol (PEG) and an esterase-responsive hydrophobic dendron, to prepare and study two diverse strategies for loading of enzyme-responsive micelles. In the first type of micelles, hydrophobic coumarin-derived dyes were encapsulated noncovalently inside the hydrophobic core of the micelle, which was composed of lipophilic enzyme-responsive dendrons. In the second type of micellar nanocarrier the hydrophobic molecular cargo was covalently linked to the end-groups of the dendron through enzyme-cleavable bonds. These amphiphilic hybrids self-assembled into micellar nanocarriers with their cargo covalently encapsulated within the hydrophobic core. Both types of micelles were highly responsive toward the activating enzyme and released their molecular cargo upon enzymatic stimulus. Importantly, while faster release was observed with noncovalent encapsulation, higher loading capacity and slower release rate were achieved with covalent encapsulation. Our results clearly indicate the great potential of enzyme-responsive micellar delivery platforms due to the ability to tune their payload capacities and release rates by adjusting the loading strategy.

  18. Encapsulation of docetaxel into PEGylated gold nanoparticles for vectorization to cancer cells.

    Science.gov (United States)

    François, Alison; Laroche, Audrey; Pinaud, Noël; Salmon, Lionel; Ruiz, Jaime; Robert, Jacques; Astruc, Didier

    2011-11-04

    Encapsulation of docetaxel and its solubilization in water was carried out in PEGylated gold nanoparticles (AuNPs) as shown by 1H NMR (600 MHz) and UV/Vis spectroscopy and dynamic light scattering. Vectorization of PEGylated AuNP-encapsulated docetaxel was probed in vitro toward human colon carcinoma (HCT15) and human breast cancer (MCF7) cells. AuNPs alone presented no cytotoxicity toward either MCF7 or HCT15 adenocarcinoma cells. AuNP-docetaxel was found to be 2.5-fold more efficient than docetaxel alone against MCF7 cells, and the IC50 value of AuNP-docetaxel against HCT15 cells was lower than that of free docetaxel; the increased efficiency brought about by AuNP drug encapsulation was ∼1.5-fold. Copyright © 2011 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  19. Encapsulated specialty oils commercialized in São Paulo state, Brazil: evaluation of identity (fatty acid profile and compliance of fatty acids and Vitamin E contents with nutrition labeling

    Directory of Open Access Journals (Sweden)

    Karen Hirashima

    2013-03-01

    Full Text Available Encapsulated specialty oils commercialized in São Paulo state, Brazil, were evaluated for their identity (fatty acids profile and compliance with nutrition labeling (fatty acids and Vitamin E (alpha tocopherol contents. Twenty one samples [flaxseed oil (6, evening primrose (5, safflower (8, borage (1, and black currant (1] purchased from local markets or collected by the health surveillance agency were analyzed. The fatty acids and vitamin E contents were analyzed by gas chromatography with flame ionization detector and liquid chromatography with UV detector, respectively. Nine samples were adulterated (5 samples of safflower oil, 3 of flaxseed oil, and one of evening primrose. Among them, 3 flaxseed and 2 safflower oil samples were probably adulterated by the addition of soybean oil. Conjugated linoleic acid (CLA was found in two safflower oils samples although the sale of oils with conjugated linoleic acid (CLA is not permitted by the National Health Surveillance Agency in Brazil (ANVISA. Only two samples presented all values in compliance with nutrition labeling (one safflower oil sample and one borage oil sample. The results show that a continuous monitoring of encapsulated specialty oils commercialized in Brazil is necessary including a greater number of samples and sanitary surveillance.

  20. Biocatalysis with Sol-Gel Encapsulated Acid Phosphatase

    Science.gov (United States)

    Kulkarni, Suhasini; Tran, Vu; Ho, Maggie K.-M.; Phan, Chieu; Chin, Elizabeth; Wemmer, Zeke; Sommerhalter, Monika

    2010-01-01

    This experiment was performed in an upper-level undergraduate biochemistry laboratory course. Students learned how to immobilize an enzyme in a sol-gel matrix and how to perform and evaluate enzyme-activity measurements. The enzyme acid phosphatase (APase) from wheat germ was encapsulated in sol-gel beads that were prepared from the precursor…