A comparison of two systems of patient immobilization for prostate radiotherapy.

Science.gov (United States)

White, Peter; Yee, Chui Ka; Shan, Lee Chi; Chung, Lee Wai; Man, Ng Ho; Cheung, Yik Shing

2014-01-22

Reproducibility of different immobilization systems, which may affect set-up errors, remains uncertain. Immobilization systems and their corresponding set-up errors influence the clinical target volume to planning target volume (CTV-PTV) margins and thus may result in undesirable treatment outcomes. This study compared the reproducibility of patient positioning with Hipfix system and whole body alpha cradle with respect to localized prostate cancer and investigated the existing CTV-PTV margins in the clinical oncology departments of two hospitals. Forty sets of data of patients with localized T1-T3 prostate cancer were randomly selected from two regional hospitals, with 20 patients immobilized by a whole-body alpha cradle system and 20 by a thermoplastic Hipfix system. Seven sets of the anterior-posterior (AP), cranial-caudal (CC) and medial-lateral (ML) deviations were collected from each patient. The reproducibility of patient positioning within the two hospitals was compared using a total vector error (TVE) parameter. In addition, CTV-PTV margins were computed using van Herk's formula. The resulting values were compared to the current CTV-PTV margins in both hospitals. The TVE values were 5.1 and 2.8 mm for the Hipfix and the whole-body alpha cradle systems respectively. TVE associated with the whole-body alpha cradle system was found to be significantly less than the Hipfix system (p < 0.05). The CC axis in the Hipfix system attained the highest frequency of large (23.6%) and serious (7.9%) set-up errors. The calculated CTV to PTV margin was 8.3, 1.9 and 2.3 mm for the Hipfix system, and 2.1, 3.4 and 1.8 mm for the whole body alpha cradle in CC, ML and AP axes respectively. All but one (CC axis using Hipfix) margin calculated did not exceed the corresponding hospital protocol. The whole body alpha cradle system was found to be significantly better than the Hipfix system in terms of reproducibility (p < 0.05), especially in the CC axis. The whole body alpha

Treatment and immobilization of intermediate level radioactive wastes

International Nuclear Information System (INIS)

Lerch, R.E.; Greenhalgh, W.O.; Partridge, J.A.; Richardson, G.L.

1977-01-01

This paper discusses a new program underway to develop and demonstrate treatment and immobilization technologies for intermediate level wastes (ILW) generated in the nuclear fuel cycle. Initial work has defined the sources, quantities and types of wastes which comprise ILW. Laboratory studies are underway to define treatment technologies for liquid ILW which contains volatile contaminants and to define immobilization parameters for the residues resulting from treatment of ILW. Immobilization agents initially being evaluated for the various residues include cement, urea-formaldehyde, and bitumen although other immobilization agents will be studied. The program also includes development of acceptable test procedures for the final immobilized products as well as development of proposed criteria for storage, transportation, and disposal of the immobilized ILW. 20 figures, 10 tables

Interfraction and intrafraction performance of the Gamma Knife Extend system for patient positioning and immobilization.

Science.gov (United States)

Schlesinger, David; Xu, Zhiyuan; Taylor, Frances; Yen, Chun-Po; Sheehan, Jason

2012-12-01

The Extend system for the Gamma Knife Perfexion makes possible multifractional Gamma Knife treatments. The Extend system consists of a vacuum-monitored immobilization frame and a positioning measurement system used to determine the location of the patient's head within the frame at the time of simulation imaging and before each treatment fraction. The measurement system consists of a repositioning check tool (RCT), which attaches to the Extend frame, and associated digital measuring gauges. The purpose of this study is to evaluate the performance of the Extend system for patient repositioning before each treatment session (fraction) and patient immobilization between (interfraction) and during (intrafraction) each session in the first 10 patients (36 fractional treatments) treated at the University of Virginia. The RCT was used to acquire a set of reference measurements for each patient position at the time of CT simulation. Repositioning measurements were acquired before each fraction, and the patient position was adjusted until the residual radial difference from the reference position measurements was less than 1 mm. After treatment, patient position measurements were acquired, and the difference between those measurements and the ones obtained for patient position before the fraction was calculated as a measure of immobilization capability. Analysis of patient setup and immobilization performance included calculation of the group mean, standard deviation (SD), and distribution of systematic (components affecting all fractions) and random (per fraction) uncertainty components. Across all patients and fractions, the mean radial setup difference from the reference measurements was 0.64 mm, with an SD of 0.24 mm. The distribution of systematic uncertainty (Σ) was 0.17 mm, and the distribution of random uncertainty (σ) was 0.16 mm. The root mean square (RMS) differences for each plate of the RCT were as follows: right = 0.35 mm; left = 0.41 mm; superior = 0.28 mm

Immobilization of yeast cells by radiation-induced polymerization

International Nuclear Information System (INIS)

Fujimura, T.; Kaetsu, I.

1982-01-01

Radiation-induced polymerization method was applied to the immobilization of yeast cells. The effects of irradiation, cooling and monomer, which are neccessary for polymerization, were recovered completely by subsequent aerobical incubation of yeast cells. The ethanol productive in immobilized yeast cells increased with the increase of aerobical incubation period. The growth of yeast cells in immobilized yeast cells was indicated. The maximum ethanol productivity in immobilized yeast cell system was around three times as much as that in free yeast cell system. (orig.)

Binary polypeptide system for permanent and oriented protein immobilization

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Bailes Julian

2010-05-01

Full Text Available Abstract Background Many techniques in molecular biology, clinical diagnostics and biotechnology rely on binary affinity tags. The existing tags are based on either small molecules (e.g., biotin/streptavidin or glutathione/GST or peptide tags (FLAG, Myc, HA, Strep-tag and His-tag. Among these, the biotin-streptavidin system is most popular due to the nearly irreversible interaction of biotin with the tetrameric protein, streptavidin. The major drawback of the stable biotin-streptavidin system, however, is that neither of the two tags can be added to a protein of interest via recombinant means (except for the Strep-tag case leading to the requirement for chemical coupling. Results Here we report a new immobilization system which utilizes two monomeric polypeptides which self-assemble to produce non-covalent yet nearly irreversible complex which is stable in strong detergents, chaotropic agents, as well as in acids and alkali. Our system is based on the core region of the tetra-helical bundle known as the SNARE (soluble N-ethylmaleimide-sensitive factor attachment protein receptor complex. This irreversible protein attachment system (IPAS uses either a shortened syntaxin helix and fused SNAP25-synaptobrevin or a fused syntaxin-synaptobrevin and SNAP25 allowing a two-component system suitable for recombinant protein tagging, capture and immobilization. We also show that IPAS is suitable for use with traditional beads and chromatography, planar surfaces and Biacore, gold nanoparticles and for protein-protein interaction in solution. Conclusions IPAS offers an alternative to chemical cross-linking, streptavidin-biotin system and to traditional peptide affinity tags and can be used for a wide range of applications in nanotechnology and molecular sciences.

Comparison of the effectiveness of different immobilization systems in different body regions using daily megavoltage CT in helical tomotherapy

Science.gov (United States)

Cheng, K-F

2014-01-01

Objective: Effective immobilization is crucial for the accurate delivery of radiotherapy. This study aimed to compare the effectiveness of the commonly used immobilization systems for different body regions using megavoltage CT (MVCT). Methods: Daily treatment set-up data from 212 patients treated by helical tomotherapy (Accuray, Sunnyvale, CA) in 6 body regions (52 head and neck, 41 chest, 38 abdomen, 36 pelvis, 18 breast and 27 cranium) were obtained. Based on a verification tool using the pre-treatment MVCT, set-up corrections for each patient were recorded. Mean systematic and random errors of lateral, longitudinal, vertical and roll directions and three-dimensional vectors were compared between immobilization systems of each region. Results: Smaller set-up deviations were observed in the Orfit system (Orfit Industries NV, Wijnegem, Belgium) of the head and neck region, while the performance of immobilization systems for the chest, abdomen and pelvis regions was similar. Larger differences were noted in the breast group, where the prone BodyFIX® system (Medical Intelligence, Medizintechnik GmbH, Schwabmünchen, Germany) was less stable than the supine VacLok® system (CIVCO Medical Solutions, Orange City, IA). Conclusion: Differences were found between the immobilization systems in the head and neck region, in which the Orfit system was relatively more effective, whereas the VacLok and BodyFIX systems performed similarly in the chest, abdomen and pelvis regions. For the breast case, the supine position with VacLok was much more stable than the prone breast technique. The results provided references for the estimation of clinical target volume–planning target volume margins. Advances in knowledge: This is the first article on comprehensive comparisons performed in immobilization systems for main body regions that provides some practical recommendations. PMID:24398111

Feasibility of using DNA-immobilized nanocellulose-based immunoadsorbent for systemic lupus erythematosus plasmapheresis.

Science.gov (United States)

Xu, Changgang; Carlsson, Daniel O; Mihranyan, Albert

2016-07-01

The goal of this project was to study the feasibility of using a DNA-immobilized nanocellulose-based immunoadsorbent for possible application in medical apheresis such as systemic lupus erythematosus (SLE) treatment. Calf thymus DNA was bound to high surface area nanocellulose membrane at varying concentrations using UV-irradiation. The DNA-immobilized samples were characterized with scanning electron microscopy, atomic force microscopy, and phosphorus elemental analysis. The anti-ds-DNA IgG binding was tested in vitro using ELISA. The produced sample showed high affinity in vitro to bind anti-ds-DNA-antibodies from mice, as much as 80% of added IgG was bound by the membrane. Furthermore, the binding efficiency was quantitatively dependent on the amount of immobilized DNA onto nanocellulose membrane. The described nanocellulose membranes are interesting immunoadsorbents for continued clinical studies. Copyright © 2016 Elsevier B.V. All rights reserved.

Design and Properties of an Immobilization Enzyme System for Inulin Conversion.

Science.gov (United States)

Hang, Hua; Wang, Changbao; Cheng, Yiqun; Li, Ning; Song, Liuli

2018-02-01

A commercial inulinase could convert inulin into fructose, which was optimized to be entrapped in the calcium alginate-gelatin beads with the immobilization yield of 86% for free inulinase activities. The optimum pH values and temperatures were 4.5 and 40 °C for the free enzyme and 5.0-5.5 and 45-50 °C for the immobilized enzyme. The kinetic parameters of V max and K m were 5.24 μmol/min and 57.6 mg/mL for the free inulinase and 4.32 μmol/min and 65.8 mg/mL for the immobilized inulinase, respectively. The immobilized enzyme retained 80% of its initial activities at 45 °C for 4 days, which could exhibit better thermal stability. The reuse of immobilized inulinase throughout the continuous batch operations was explored, which had better reusability of the immobilized biocatalyst. At the same time, the stability of immobilized enzyme in the continuous packed-bed bioreactor was estimated, which showed the better results and had its potential scale-up fructose production for inulin conversion.

Assessing attitudes toward spinal immobilization.

Science.gov (United States)

Bouland, Andrew J; Jenkins, J Lee; Levy, Matthew J

2013-10-01

Prospective studies have improved knowledge of prehospital spinal immobilization. The opinion of Emergency Medical Services (EMS) providers regarding spinal immobilization is unknown, as is their knowledge of recent research advances. To examine the attitudes, knowledge, and comfort of prehospital and Emergency Department (ED) EMS providers regarding spinal immobilization performed under a non-selective protocol. An online survey was conducted from May to July of 2011. Participants were drawn from the Howard County Department of Fire and Rescue Services and the Howard County General Hospital ED. The survey included multiple choice questions and responses on a modified Likert scale. Correlation analysis and descriptive data were used to analyze results. Comfort using the Kendrick Extrication Device was low among ED providers. Experienced providers were more likely to indicate comfort using this device. Respondents often believed that spinal immobilization is appropriate in the management of penetrating trauma to the chest and abdomen. Reported use of padding decreased along with the frequency with which providers practice and encounter immobilized patients. Respondents often indicated that they perform spinal immobilization due solely to mechanism of injury. Providers who feel as if spinal immobilization is often performed unnecessarily were more likely to agree that immobilization causes an unnecessary delay in patient care. The results demonstrate the need for improved EMS education in the use of the Kendrick Extrication Device, backboard padding, and spinal immobilization in the management of penetrating trauma. The attitudes highlighted in this study are relevant to the implementation of a selective spinal immobilization protocol. Copyright © 2013 Elsevier Inc. All rights reserved.

Surface cell immobilization within perfluoroalkoxy microchannels

Energy Technology Data Exchange (ETDEWEB)

Stojkovič, Gorazd; Krivec, Matic [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana (Slovenia); Vesel, Alenka [Jožef Stefan Institute, Jamova cesta 39, 1000 Ljubljana (Slovenia); Marinšek, Marjan [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana (Slovenia); Žnidaršič-Plazl, Polona, E-mail: polona.znidarsic@fkkt.uni-lj.si [Faculty of Chemistry and Chemical Technology, University of Ljubljana, Aškerčeva 5, SI-1000 Ljubljana (Slovenia)

2014-11-30

Graphical abstract: - Highlights: • A very efficient approach for immobilization of cells into microreactors is presented. • It is applicable to various materials, including PFA and cyclic olefin (co)polymers. • It was used to immobilize different prokaryotic and eukaryotic microbes. • Cells were immobilized on the surface in high density and showed good stability. • Mechanisms of APTES interactions with target materials are proposed. - Abstract: Perfluoroalkoxy (PFA) is one of the most promising materials for the fabrication of cheap, solvent resistant and reusable microfluidic chips, which have been recently recognized as effective tools for biocatalytic process development. The application of biocatalysts significantly depends on efficient immobilization of enzymes or cells within the reactor enabling long-term biocatalyst use. Functionalization of PFA microchannels by 3-aminopropyltriethoxysilane (ATPES) and glutaraldehyde was used for rapid preparation of microbioreactors with surface-immobilized cells. X-ray photoelectron spectroscopy and scanning electron microscopy were used to accurately monitor individual treatment steps and to select conditions for cell immobilization. The optimized protocol for Saccharomyces cerevisiae immobilization on PFA microchannel walls comprised ethanol surface pretreatment, 4 h contacting with 10% APTES aqueous solution, 10 min treatment with 1% glutaraldehyde and 20 min contacting with cells in deionized water. The same protocol enabled also immobilization of Escherichia coli, Pseudomonas putida and Bacillus subtilis cells on PFA surface in high densities. Furthermore, the developed procedure has been proved to be very efficient also for surface immobilization of tested cells on other materials that are used for microreactor fabrication, including glass, polystyrene, poly (methyl methacrylate), polycarbonate, and two olefin-based polymers, namely Zeonor{sup ®} and Topas{sup ®}.

Phospholipid-sepiolite biomimetic interfaces for the immobilization of enzymes.

Science.gov (United States)

Wicklein, Bernd; Darder, Margarita; Aranda, Pilar; Ruiz-Hitzky, Eduardo

2011-11-01

Biomimetic interfaces based on phosphatidylcholine (PC) assembled to the natural silicate sepiolite were prepared for the stable immobilization of the urease and cholesterol oxidase enzymes. This is an important issue in practical advanced applications such as biocatalysis or biosensing. The supported lipid bilayer (BL-PC), prepared from PC adsorption, was used for immobilization of enzymes and the resulting biomimetic systems were compared to several other supported layers including a lipid monolayer (ML-PC), a mixed phosphatidylcholine/octyl-galactoside layer (PC-OGal), a cetyltrimethylammonium monolayer (CTA), and also to the bare sepiolite surface. Interfacial characteristics of these layers were investigated with a focus on layer packing density, hydrophilicity/hydrophobicity, and surface charge, which are being considered as key points for enzyme immobilization and stabilization of their biological activity. Cytoplasmic urease and membrane-bound cholesterol oxidase, which served as model enzymes, were immobilized on the different PC-based hybrid materials to probe their biomimetic character. Enzymatic activity was assessed by cyclic voltammetry and UV-vis spectrophotometry. The resulting enzyme/bio-organoclay hybrids were applied as active phase of a voltammetric urea biosensor and cholesterol bioreactor, respectively. Urease supported on sepiolite/BL-PC proved to maintain its enzymatic activity over several months while immobilized cholesterol oxidase demonstrated high reusability as biocatalyst. The results emphasize the good preservation of bioactivity due to the accommodation of the enzymatic system within the biomimetic lipid interface on sepiolite.

Radioactive seed immobilization techniques for interstitial brachytherapy

International Nuclear Information System (INIS)

Yan, K.; Podder, T.; Buzurovic, I.; Hu, Y.; Dicker, A.; Valicenti, R.; Yu, Y.; Messing, E.; Rubens, D.; Sarkar, N.; Ng, W.

2008-01-01

In prostate brachytherapy, seeds can detach from their deposited sites and move locally in the pelvis or migrate to distant sites including the pulmonary and cardiac regions. Undesirable consequences of seed migration include inadequate dose coverage of the prostate and tissue irradiation effects at the site of migration. Thus, it is clinically important to develop seed immobilization techniques. We first analyze the possible causes for seed movement, and propose three potential techniques for seed immobilization: (1) surgical glue, (2) laser coagulation and (3) diathermy coagulation. The feasibility of each method is explored. Experiments were carried out using fresh bovine livers to investigate the efficacy of seed immobilization using surgical glue. Results have shown that the surgical glue can effectively immobilize the seeds. Evaluation of the radiation dose distribution revealed that the non-immobilized seed movement would change the planned isodose distribution considerably; while by using surgical glue method to immobilize the seeds, the changes were negligible. Prostate brachytherapy seed immobilization is necessary and three alternative mechanisms are promising for addressing this issue. Experiments for exploring the efficacy of the other two proposed methods are ongoing. Devices compatible with the brachytherapy procedure will be designed in future. (orig.)

A comparison of two systems of patient immobilization for prostate radiotherapy

Science.gov (United States)

2014-01-01

Background Reproducibility of different immobilization systems, which may affect set-up errors, remains uncertain. Immobilization systems and their corresponding set-up errors influence the clinical target volume to planning target volume (CTV-PTV) margins and thus may result in undesirable treatment outcomes. This study compared the reproducibility of patient positioning with Hipfix system and whole body alpha cradle with respect to localized prostate cancer and investigated the existing CTV-PTV margins in the clinical oncology departments of two hospitals. Methods Forty sets of data of patients with localized T1-T3 prostate cancer were randomly selected from two regional hospitals, with 20 patients immobilized by a whole-body alpha cradle system and 20 by a thermoplastic Hipfix system. Seven sets of the anterior-posterior (AP), cranial-caudal (CC) and medial-lateral (ML) deviations were collected from each patient. The reproducibility of patient positioning within the two hospitals was compared using a total vector error (TVE) parameter. In addition, CTV-PTV margins were computed using van Herk’s formula. The resulting values were compared to the current CTV-PTV margins in both hospitals. Results The TVE values were 5.1 and 2.8 mm for the Hipfix and the whole-body alpha cradle systems respectively. TVE associated with the whole-body alpha cradle system was found to be significantly less than the Hipfix system (p < 0.05). The CC axis in the Hipfix system attained the highest frequency of large (23.6%) and serious (7.9%) set-up errors. The calculated CTV to PTV margin was 8.3, 1.9 and 2.3 mm for the Hipfix system, and 2.1, 3.4 and 1.8 mm for the whole body alpha cradle in CC, ML and AP axes respectively. All but one (CC axis using Hipfix) margin calculated did not exceed the corresponding hospital protocol. The whole body alpha cradle system was found to be significantly better than the Hipfix system in terms of reproducibility (p < 0.05), especially

Competitive immobilization of Pb in an aqueous ternary-metals system by soluble phosphates with varying pH.

Science.gov (United States)

Zhang, Zhuo; Ren, Jie; Wang, Mei; Song, Xinlai; Zhang, Chao; Chen, Jiayu; Li, Fasheng; Guo, Guanlin

2016-09-01

Chemical immobilization by phosphates has been widely and successfully applied to treat Pb in wastewater and contaminated soils. Pb in wastewaters and soils, however, always coexists with other heavy metals and their competitive reactions with phosphates have not been quantitatively and systematically studied. In this approach, immobilization of Pb, Zn, and Cd by mono-, di-, and tripotassium phosphate (KH2PO4, K2HPO4, and K3PO4) was observed in the single- and ternary-metals solutions. The immobilization rates of the three metals were determined by the residual concentration. The mineral composition and structure of the precipitates were characterized by powder X-ray diffraction (XRD) analysis and scanning electron microscopy (SEM). The results indicated that competitive reaction occurred in Pb-Zn-Cd ternary system, with immobilization rates decrease of system. The reaction of Pb with three phosphates exhibited intense competitiveness and the phosphates had a stronger affinity for Pb when Cl(-) was added. Pb-phosphate minerals formed by KH2PO4 with the better crystalline characteristics and largest size were very stable with a low dissolution rate (system. Copyright © 2016 Elsevier Ltd. All rights reserved.

An overview of technologies for immobilization of enzymes and surface analysis techniques for immobilized enzymes

Science.gov (United States)

Mohamad, Nur Royhaila; Marzuki, Nur Haziqah Che; Buang, Nor Aziah; Huyop, Fahrul; Wahab, Roswanira Abdul

2015-01-01

The current demands of sustainable green methodologies have increased the use of enzymatic technology in industrial processes. Employment of enzyme as biocatalysts offers the benefits of mild reaction conditions, biodegradability and catalytic efficiency. The harsh conditions of industrial processes, however, increase propensity of enzyme destabilization, shortening their industrial lifespan. Consequently, the technology of enzyme immobilization provides an effective means to circumvent these concerns by enhancing enzyme catalytic properties and also simplify downstream processing and improve operational stability. There are several techniques used to immobilize the enzymes onto supports which range from reversible physical adsorption and ionic linkages, to the irreversible stable covalent bonds. Such techniques produce immobilized enzymes of varying stability due to changes in the surface microenvironment and degree of multipoint attachment. Hence, it is mandatory to obtain information about the structure of the enzyme protein following interaction with the support surface as well as interactions of the enzymes with other proteins. Characterization technologies at the nanoscale level to study enzymes immobilized on surfaces are crucial to obtain valuable qualitative and quantitative information, including morphological visualization of the immobilized enzymes. These technologies are pertinent to assess efficacy of an immobilization technique and development of future enzyme immobilization strategies. PMID:26019635

[Effect of External Irradiation and Immobilization Stress on the Reproductive System of Male Rats].

Science.gov (United States)

Vereschako, G G; Tshueshova, N V; Gorokh, G A; Kozlov, I G; Naumov, A D

2016-01-01

We studied the state of the reproductive system of male rats after irradiation at a dose of 2.0 Gy, immobilization stress (6 hours/day for 7 days) and their combined effects. On the 30th day after the combined treatment (37 days after irradiation) a decrease in the testicular weight by almost 50% compared with the control and lesions connected with the process of spermatogenesis are observed. In the remote period--on the 60th day (67th after irradiation) the effect of irradiation and irradiation in combination with immobilization stress leads to a sharp drop in the number of epididymal sperm (up to 18% of the control), and a reduction of their viability. The reaction ofthe reproductive system to the immobilization stress is expressed in a certain increase in the mass of the testes and epididymis, moderate imbalances in the composition of spermatogenic cells in the testis tissue, and in the long term--in the increased number of epididymal sperm and the decrease in their viability. Changes of testosterone in the blood serum, especially significant for the combined effect, reflect impairments of the regulation of the reproductive system of males under these conditions. With regard to individual indicators of the reproductive system of male rats in some cases, the- combined effects of radiation and stress had a synergistic, or, on the contrary, antagonistic character.

A precision cranial immobilization system for conformal stereotactic fractionated radiation therapy

International Nuclear Information System (INIS)

Rosenthal, Stanley J.; Gall, Kenneth P.; Jackson, Matthew; Thornton, Allan F.

1995-01-01

Purpose: Conformal radiotherapy has been shown to benefit from precision alignment of patient target to therapy beam (1, 6, 13). This work describes an optimized immobilization system for the fractionated treatment of intracranial targets. A study of patient motion demonstrates the high degree of immobilization which is available. Methods and Materials: A system using dental fixation and a thermoplastic mask that relocates on a rigid frame is described. The design permits scanning studies using computed tomography (CT) and magnetic resonance imaging (MR), conventional photon radiotherapy, and high precision stereotactic proton radiotherapy to be performed with minimal repositioning variation. Studies of both intratreatment motion and daily setup reliability are performed on patients under treatment for paranasal sinus carcinoma. Multiple radiographs taken during single treatments provide the basis for a three-dimensional (3D) motion analysis. Additionally, studies of orthogonal radiographs used to setup for proton treatments and verification port films from photon treatments are used to establish day to day patient position variation in routine use. Results: Net 3D patient motion during any treatment is measured to be 0.9 ± 0.4 mm [mean ± standard deviation (SD)] and rotation about any body axis is 0.14 ± 0.67 degrees (mean ± SD). Day-to-day setup accuracy to laser marks is limited to 2.3 mm (mean) systematic error and 1.6 mm (mean) random error. Conclusion: We conclude that the most stringent immobilization requirements of 3D conformal radiotherapy adjacent to critical normal structures can be met with a high precision system such as the one described here. Without the use of pretreatment verification, additional developments in machine and couch design are needed to assure that patient repositioning accuracy is comparable to the best level of patient immobility achievable

Production of Biodiesel Using Immobilized Lipase and the Characterization of Different Co-Immobilizing Agents and Immobilization Methods

Directory of Open Access Journals (Sweden)

Kang Zhao

2016-08-01

Full Text Available Lipase from Candida sp. 99–125 is widely employed to catalyzed transesterification and can be used for biodiesel production. In this study, the lipase was immobilized by combined adsorption and entrapment to catalyze biodiesel production from waste cooking oil (WCO via transesterification, and investigating co-immobilizing agents as additives according to the enzyme activity. The addition of the mixed co-immobilizing agents has positive effects on the activities of the immobilized lipase. Three different immobilizing methods were compared by the conversion ratio of biodiesel and structured by Atom Force Microscopy (AFM and Scanning Electron Microscopy (SEM, respectively. It was found that entrapment followed by adsorption was the best method. The effect of the co-immobilizing agent amount, lipase dosage, water content, and reuse ability of the immobilized lipase was investigated. By comparison with previous research, this immobilized lipase showed good reuse ability: the conversion ratio excesses 70% after 10 subsequent reactions, in particular, was better than Novozym435 and TLIM on waste cooking oil for one unit of lipase.

Biodiesel production with immobilized lipase: A review.

Science.gov (United States)

Tan, Tianwei; Lu, Jike; Nie, Kaili; Deng, Li; Wang, Fang

2010-01-01

Fatty acid alkyl esters, also called biodiesel, are environmentally friendly and show great potential as an alternative liquid fuel. Biodiesel is produced by transesterification of oils or fats with chemical catalysts or lipase. Immobilized lipase as the biocatalyst draws high attention because that process is "greener". This article reviews the current status of biodiesel production with immobilized lipase, including various lipases, immobilization methods, various feedstocks, lipase inactivation caused by short chain alcohols and large scale industrialization. Adsorption is still the most widely employed method for lipase immobilization. There are two kinds of lipase used most frequently especially for large scale industrialization. One is Candida antartica lipase immobilized on acrylic resin, and the other is Candida sp. 99-125 lipase immobilized on inexpensive textile membranes. However, to further reduce the cost of biodiesel production, new immobilization techniques with higher activity and stability still need to be explored. Copyright 2010 Elsevier Inc. All rights reserved.

Combined action of radiation and immobilization stress on reproductive system male rats station

International Nuclear Information System (INIS)

Vereshchako, G.G.; Chueshova, N.V.; Gorokh, G.A.; Naumov, A.D.

2015-01-01

It was studied the effect of irradiation (0.5 Gy), immobilization stress (3 hours/day for 7 days), and their combined effect on the reproductive system of male rats. The action of these factors, individually or together caused a significant imbalance quantitative composition of the spermatogenic cells in the testis tissue, marked decrease the viability of epididymal spermatozoa, and increased DNA fragmentation in them, which may result in reduced fertility of animals. Under these influences reproductive disorders save for a long time. In some cases, the effects of the combined action of irradiation and immobilization stress is significantly higher than the isolated action of each of them. (authors)

Management of primary anterior shoulder dislocations using immobilization.

Science.gov (United States)

Smith, Brent I; Bliven, Kellie C Huxel; Morway, Genoveffa R; Hurbanek, Jason G

2015-05-01

Reference/Citation : Paterson WH, Throckmorton TW, Koester M, Azar FM, Kuhn JE. Position and duration of immobilization after primary anterior shoulder dislocation: a systemic review and meta-analysis of the literature. J Bone Joint Surg Am. 2010;92(18):2924-2933. Does an optimum duration and position of immobilization after primary anterior shoulder dislocation exist for reducing recurrence rates? MEDLINE/PubMed, EMBASE, and Cochrane databases were searched up to December 2009 without limitations. The search terms for all databases used were shoulder AND dislocation and shoulder AND immobilization. Criteria used to include articles were (1) English language, (2) prospective level I or level II studies (according to Journal of Bone & Joint Surgery guidelines), (3) nonoperative management of initial anterior shoulder dislocation, (4) minimum follow-up of 1 year, and (5) rate of recurrent dislocation as a reported outcome. A standardized evaluation method was used to extract data to allow assessment of methods issues and statistical analysis to determine sources of bias. The primary outcome was the recurrence rate after nonoperative management of anterior shoulder dislocation. Additional data extracted and used in subanalyses included duration and position of immobilization and age at the time of initial dislocation. Data were analyzed to determine associations among groups using 2-tailed Fisher exact tests. For pooled categorical data, relative risk of recurrent dislocation, 95% confidence intervals, and heterogeneity using the I(2) statistic and χ(2) tests were calculated for individual studies. The Mantel-Haenszel method was used to combine studies and estimate overall relative risk of recurrent dislocation and 95% confidence intervals. The statistical difference between duration of immobilization and position was determined using z tests for overall effect. Pooled results were presented as forest plots. In the initial search of the databases, the authors

Three-dimensional motion analysis of an improved head immobilization system for simulation, CT, MRI, and PET imaging

International Nuclear Information System (INIS)

Thornton, A.F. Jr.; Ten Haken, R.K.; Gerhardsson, A.; Correll, M.

1991-01-01

A mask/marker immobilization system for the routine radiation therapy treatment of head and neck disease is described, utilizing a commercially available thermoplastic mesh, indexed and mounted for a rigid frame attached to the therapy couch. Designed to permit CT, MRI, and PET diagnostics scans of the patient to be performed in the simulation and treatment position employing the same mask, the system has been tested in order to demonstrate the reproducibility of immobilization throughout a radical course of irradiation. Three-dimensional analysis of patient position over an 8-week course of daily radiation treatment has been performed for 9 patients from digitization of anatomic points identified on orthogonal radiographs. Studies employing weekly constructed system permits rapid mask formation to be performed on the treatment simulator, resulting in an immobilization device comparable to masks produced with vacuum-forming techniques. Details of motion analysis and central axis CT, MRI, and PET markers are offered. (author). 16 refs.; 3 figs

Construction and Characterization of a Chitosan-Immobilized-Enzyme and β-Cyclodextrin-Included-Ferrocene-Based Electrochemical Biosensor for H2O2 Detection

Directory of Open Access Journals (Sweden)

Wenbo Dong

2017-07-01

Full Text Available An electrochemical detection biosensor was prepared with the chitosan-immobilized-enzyme (CTS-CAT and β-cyclodextrin-included-ferrocene (β-CD-FE complex for the determination of H2O2. Ferrocene (FE was included in β-cyclodextrin (β-CD to increase its stability. The structure of the β-CD-FE was characterized. The inclusion amount, inclusion rate, and electrochemical properties of inclusion complexes were determined to optimize the reaction conditions for the inclusion. CTS-CAT was prepared by a step-by-step immobilization method, which overcame the disadvantages of the conventional preparation methods. The immobilization conditions were optimized to obtain the desired enzyme activity. CTS-CAT/β-CD-FE composite electrodes were prepared by compositing the CTS-CAT with the β-CD-FE complex on a glassy carbon electrode and used for the electrochemical detection of H2O2. It was found that the CTS-CAT could produce a strong reduction peak current in response to H2O2 and the β-CD-FE could amplify the current signal. The peak current exhibited a linear relationship with the H2O2 concentration in the range of 1.0 × 10−7–6.0 × 10−3 mol/L. Our work provided a novel method for the construction of electrochemical biosensors with a fast response, good stability, high sensitivity, and a wide linear response range based on the composite of chitosan and cyclodextrin.

Evaluation of a Thermoplastic Immobilization System for Breast and Chest Wall Radiation Therapy

International Nuclear Information System (INIS)

Strydhorst, Jared H.; Caudrelier, Jean-Michel; Clark, Brenda G.; Montgomery, Lynn A.; Fox, Greg; MacPherson, Miller S.

2011-01-01

We report on the impact of a thermoplastic immobilization system on intra- and interfraction motion for patients undergoing breast or chest wall radiation therapy. Patients for this study were treated using helical tomotherapy. All patients were immobilized using a thermoplastic shell extending from the shoulders to the ribcage. Intrafraction motion was assessed by measuring maximum displacement of the skin, heart, and chest wall on a pretreatment 4D computed tomography, while inter-fraction motion was inferred from patient shift data arising from daily image guidance procedures on tomotherapy. Using thermoplastic immobilization, the average maximum motion of the external contour was 1.3 ± 1.6 mm, whereas the chest wall was found to be 1.6 ± 1.9 mm. The day-to-day setup variation was found to be large, with random errors of 4.0, 12.0, and 4.5 mm in the left-right, superior-inferior, and anterior-posterior directions, respectively, and the standard deviations of the systematic errors were found to be 2.7, 9.8, and 4.1 mm. These errors would be expected to dominate any respiratory motion but can be mitigated by daily online image guidance. Using thermoplastic immobilization can effectively reduce respiratory motion of the chest wall and external contour, but these gains can only be realized if daily image guidance is used.

Oxygen Limited Bioreactors System For Nitrogen Removal Using Immobilized Mix Culture

Science.gov (United States)

Pathak, B. K.; Sumino, T.; Saiki, Y.; Kazama, F.

2005-12-01

Recently nutrients concentrations especially nitrogen in natural water is alarming in the world wide. Most of the effort is being done on the removal of high concentration of nitrogen especially from the wastewater treatment plants. The removal efficiency is targeted in all considering the effluent discharge standard set by the national environment agency. In many cases, it does not meet the required standard and receiving water is being polluted. Eutrophication in natural water bodies has been reported even if the nitrogen concentration is low and self purification of natural systems itself is not sufficient to remove the nitrogen due to complex phenomenon. In order to recover the pristine water environment, it is very essential to explore bioreactor systems for natural water systems using immobilized mix culture. Microorganism were entrapped in Polyethylene glycol (PEG) prepolymer gel and cut into 3mm cubic immobilized pellets. Four laboratory scale micro bio-reactors having 0.1 L volumes were packed with immobilized pellets with 50% compact ratio. RUN1, RUN2, RUN3 and RUN4 were packed with immobilized pellets from reservoirs sediments, activated sludge (AS), mixed of AS, AG and biodegradable plastic and anaerobic granules (AG) respectively. Water from Shiokawa Reservoirs was feed to all reactors with supplemental ammonia and nitrite nitrogen as specified in the results and discussions. The reactors were operated dark incubated room in continuous flow mode with hydraulic retention time of 12 hours under oxygen limiting condition. Ammonium, nitrate nitrite nitrogen and total organic carbon (TOC) concentrations were measured as described in APWA and AWWA (1998). Laboratory scale four bioreactors containing different combination of immobilized cell were monitored for 218 days. Influent NH4+-N and NO2--N concentration were 2.27±0.43 and 2.05±0.41 mg/l respectively. Average dissolved oxygen concentration and pH in the reactors were 0.40-2.5 mg/l and pH 6

Immobilization of xanthine oxidase on a polyaniline silicone support.

Science.gov (United States)

Nadruz, W; Marques, E T; Azevedo, W M; Lima-Filho, J L; Carvalho, L B

1996-03-01

A polyaniline silicone support to immobilize xanthine oxidase is proposed as a reactor coil to monitor the action of xanthine oxidase on hypoxanthine, xanthine and 6-mercaptopurine. A purified xanthine oxidase immobilized on this support lost 80% of the initial activity after 12 min of use. Co-immobilization of superoxide dismutase and catalase increased the stability of immobilized xanthine oxidase so that the derivative maintained 79% of its initial activity after 4.6 h of continuous use in which 1.5 mumol purine bases were converted by the immobilized enzyme system. There is no evidence of either polyaniline or protein leaching from the coil during 3 h of continuous use. When solutions (10 ml) of hypoxanthine, xanthine and 6-mercaptopurine were circulated individually through the xanthine oxidase-superoxide dismutase-catalase-polyaniline coil (1 mm internal diameter and 3 m in length, 3 ml internal volume) activities of 8.12, 11.17 and 1.09 nmol min-1 coil-1, respectively, were obtained. The advantages of the reactor configuration and the redox properties of the polymer, particularly with respect to immobilized oxidoreductases, make this methodology attractive for similar enzyme systems. This immobilized enzyme system using polyaniline-silicone as support converted 6-mercaptopurine to 6-thiouric acid with equal efficiency as resins based on polyacrylamide and polyamide 11.

Application of magnetic nanoparticles in smart enzyme immobilization.

Science.gov (United States)

Vaghari, Hamideh; Jafarizadeh-Malmiri, Hoda; Mohammadlou, Mojgan; Berenjian, Aydin; Anarjan, Navideh; Jafari, Nahideh; Nasiri, Shahin

2016-02-01

Immobilization of enzymes enhances their properties for efficient utilization in industrial processes. Magnetic nanoparticles, due to their high surface area, large surface-to-volume ratio and easy separation under external magnetic fields, are highly valued. Significant progress has been made to develop new catalytic systems that are immobilized onto magnetic nanocarriers. This review provides an overview of recent developments in enzyme immobilization and stabilization protocols using this technology. The current applications of immobilized enzymes based on magnetic nanoparticles are summarized and future growth prospects are discussed. Recommendations are also given for areas of future research.

Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae)

OpenAIRE

Dali, Seniwati; Patong, A. B. D. Rauf; Jalaluddin, M. Noor; Pirman; Hamzah, Baharuddin

2011-01-01

Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum ...

Lipase B from Candida antarctica Immobilized on a Silica-Lignin Matrix as a Stable and Reusable Biocatalytic System

Directory of Open Access Journals (Sweden)

Jakub Zdarta

2016-12-01

Full Text Available A study was conducted of the possible use of a silica-lignin hybrid as a novel support for the immobilization of lipase B from Candida antarctica. Results obtained by elemental analysis, Fourier transform infrared spectroscopy (FTIR, X-ray photoelectron spectroscopy (XPS, and atomic force microscopy (AFM, as well as the determination of changes in porous structure parameters, confirmed the effective immobilization of the enzyme on the surface of the composite matrix. Based on a hydrolysis reaction, a determination was made of the retention of activity of the immobilized lipase, found to be 92% of that of the native enzyme. Immobilization on a silica-lignin matrix produces systems with maximum activity at pH = 8 and at a temperature of 40 °C. The immobilized enzyme exhibited increased thermal and chemical stability and retained more than 80% of its activity after 20 reaction cycles. Moreover immobilized lipase exhibited over 80% of its activity at pH range 7–9 and temperature from 30 °C to 60 °C, while native Candida antarctica lipase B (CALB exhibited the same only at pH = 7 and temperature of 30 °C.

Catalytical Properties of Free and Immobilized Aspergillus niger Tannase

Directory of Open Access Journals (Sweden)

Abril Flores-Maltos

2011-01-01

Full Text Available A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methyl gallate as substrates. KM and Vmax values for free enzyme were very similar for both substrates. But, after immobilization, KM and Vmax values increased drastically using tannic acid as substrate. These results indicated that immobilized tannase is a better biocatalyst than free enzyme for applications on liquid systems with high tannin content, such as bioremediation of tannery or olive-mill wastewater.

Catalytical Properties of Free and Immobilized Aspergillus niger Tannase.

Science.gov (United States)

Flores-Maltos, Abril; Rodríguez-Durán, Luis V; Renovato, Jacqueline; Contreras, Juan C; Rodríguez, Raúl; Aguilar, Cristóbal N

2011-01-01

A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methyl gallate as substrates. K(M) and V(max) values for free enzyme were very similar for both substrates. But, after immobilization, K(M) and V(max) values increased drastically using tannic acid as substrate. These results indicated that immobilized tannase is a better biocatalyst than free enzyme for applications on liquid systems with high tannin content, such as bioremediation of tannery or olive-mill wastewater.

Modeling and simulation of enzymatic gluconic acid production using immobilized enzyme and CSTR-PFTR circulation reaction system.

Science.gov (United States)

Li, Can; Lin, Jianqun; Gao, Ling; Lin, Huibin; Lin, Jianqiang

2018-04-01

Production of gluconic acid by using immobilized enzyme and continuous stirred tank reactor-plug flow tubular reactor (CSTR-PFTR) circulation reaction system. A production system is constructed for gluconic acid production, which consists of a continuous stirred tank reactor (CSTR) for pH control and liquid storage and a plug flow tubular reactor (PFTR) filled with immobilized glucose oxidase (GOD) for gluconic acid production. Mathematical model is developed for this production system and simulation is made for the enzymatic reaction process. The pH inhibition effect on GOD is modeled by using a bell-type curve. Gluconic acid can be efficiently produced by using the reaction system and the mathematical model developed for this system can simulate and predict the process well.

Management of immobilization and its complication for elderly.

Science.gov (United States)

Laksmi, Purwita W; Harimurti, Kuntjoro; Setiati, Siti; Soejono, Czeresna H; Aries, Wanarani; Roosheroe, Arya Govinda

2008-10-01

Increased life expectancy have an effect on the rising percentage of elderly population in Indonesia and health problem associated with the elderly, particularly immobilization. Immobilization may cause various complications, especially when it has been overlooked without any appropriate and proper medical care in keeping with the procedures. High incidence of immobilization in elderly and the life-threatening complication call for an agreement on management of immobilization and its complication. Management of immobilization needs interdisciplinary team-work cooperation, the patients and their family. The management may be commenced through a complete geriatric review, formulating functional goals and constructing therapeutic plan. Various medical conditions and external factors that may act as risk factors of immobilization as well as drugs intake that may exaggerate the immobilization should be evaluated and optimally managed. Any complication due to immobilization and other concomitant disease/condition should be recognized and managed comprehensively in order to reduce morbidity and mortality. Management of immobilization and its complications include pharmacological and non-pharmacological treatment, i.e. various mobility exercises, utilization of ambulatory device and supporting appliance for assisting patients in stand-up position, as well as the management of urinary voiding and defecation.

Optimizing Immobilized Enzyme Performance in Cell-Free Environments to Produce Liquid Fuels

Energy Technology Data Exchange (ETDEWEB)

Belfort, Georges [Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Chemical and Biological Engineering; Grimaldi, Joseph J. [Rensselaer Polytechnic Inst., Troy, NY (United States). Dept. of Chemical and Biological Engineering

2015-01-27

Limitations on biofuel production using cell culture (Escherichia coli, Clostridium, Saccharomyces cerevisiae, brown microalgae, blue-green algae and others) include low product (alcohol) concentrations (≤0.2 vol%) due to feedback inhibition, instability of cells, and lack of economical product recovery processes. To overcome these challenges, an alternate simplified biofuel production scheme was tested based on a cell-free immobilized enzyme system. Using this cell free system, we were able to obtain about 2.6 times higher concentrations of iso-butanol using our non-optimized system as compared with live cell systems. This process involved two steps: (i) converts acid to aldehyde using keto-acid decarboxylase (KdcA), and (ii) produces alcohol from aldehyde using alcohol dehydrogenase (ADH) with a cofactor (NADH) conversion from inexpensive formate using a third enzyme, formate dehydrogenase (FDH). To increase stability and conversion efficiency with easy separations, the first two enzymes were immobilized onto methacrylate resin. Fusion proteins of labile KdcA (fKdcA) were expressed to stabilize the covalently immobilized KdcA. Covalently immobilized ADH exhibited long-term stability and efficient conversion of aldehyde to alcohol over multiple batch cycles without fusions. High conversion rates and low protein leaching were achieved by covalent immobilization of enzymes on methacrylate resin. The complete reaction scheme was demonstrated by immobilizing both ADH and fKdcA and using FDH free in solution. The new system without in situ removal of isobutanol achieved a 55% conversion of ketoisovaleric acid to isobutanol at a concentration of 0.5 % (v/v). Further increases in titer will require continuous removal of the isobutanol using our novel brush membrane system that exhibits a 1.5 fold increase in the separation factor of isobutanol from water versus that obtained for commercial silicone rubber membranes. These bio-inspired brush membranes are based on the

Evaluation of fungal laccase immobilized on natural nanostructured bacterial cellulose

Directory of Open Access Journals (Sweden)

Lin eChen

2015-11-01

Full Text Available The aim of this work was to assess the possibility of using native bacterial nanocellulose (BC as a carrier for laccase immobilization. BC was synthesized by Gluconacetobacter xylinus, which was statically cultivated in a mannitol-based medium and was freeze-dried to form BC sponge after purification. For the first time, fungal laccase from Trametes versicolor was immobilized on the native nanofibril network-structured BC sponge through physical adsorption and cross-linking with glutaraldehyde. The properties including morphologic and structural features of the BC as well as the immobilized enzyme were thoroughly investigated. It was found that enzyme immobilized by cross-linking exhibited broader pH operation range of high catalytic activity as well as higher running stability compared to free and adsorbed enzyme. Using ABTS as substrate, the optimum pH value was 3.5 for the adsorption-immobilized laccase and 4.0 for the crosslinking-immobilized laccase. The immobilized enzyme retained 69% of the original activity after being recycled 7 times. Novel applications of the BC-immobilized enzyme tentatively include active packaging, construction of biosensors, and establishment of bioreactors.

Immobilization Patterns and Dynamics of Acetate-Utilizing Methanogens Immobilized in Sterile Granular Sludge in Upflow Anaerobic Sludge Blanket Reactors

Science.gov (United States)

Schmidt, Jens Ejbye; Ahring, Birgitte Kjær

1999-01-01

Sterile granular sludge was inoculated with either Methanosarcina mazeii S-6, Methanosaeta concilii GP-6, or both species in acetate-fed upflow anaerobic sludge blanket (UASB) reactors to investigate the immobilization patterns and dynamics of aceticlastic methanogens in granular sludge. After several months of reactor operation, the methanogens were immobilized, either separately or together. The fastest immobilization was observed in the reactor containing M. mazeii S-6. The highest effluent concentration of acetate was observed in the reactor with only M. mazeii S-6 immobilized, while the lowest effluent concentration of acetate was observed in the reactor where both types of methanogens were immobilized together. No changes were observed in the kinetic parameters (Ks and μmax) of immobilized M. concilii GP-6 or M. mazeii S-6 compared with suspended cultures, indicating that immobilization does not affect the growth kinetics of these methanogens. An enzyme-linked immunosorbent assay using polyclonal antibodies against either M. concilii GP-6 or M. mazeii S-6 showed significant variations in the two methanogenic populations in the different reactors. Polyclonal antibodies were further used to study the spatial distribution of the two methanogens. M. concilii GP-6 was immobilized only on existing support material without any specific pattern. M. mazeii S-6, however, showed a different immobilization pattern: large clumps were formed when the concentration of acetate was high, but where the acetate concentration was low this strain was immobilized on support material as single cells or small clumps. The data clearly show that the two aceticlastic methanogens immobilize differently in UASB systems, depending on the conditions found throughout the UASB reactor. PMID:10049862

Immobile Complex Verbs in Germanic

DEFF Research Database (Denmark)

Vikner, Sten

2005-01-01

the V° requirements or the V* requirements. Haider (1993, p. 62) and Koopman (1995), who also discuss such immobile verbs, only account for verbs with two prefix-like parts (e.g., German uraufführen ‘to perform (a play) for the first time' or Dutch herinvoeren ‘to reintroduce'), not for the more...... frequent type with only one prefix-like part (e.g., German bauchreden/Dutch buikspreken ‘to ventriloquize'). This analysis will try to account not only for the data discussed in Haider (1993) and Koopman (1995) but also for the following: - why immobile verbs include verbs with only one prefix-like part...... are immobile, - why such verbs are not found in Germanic VO-languages such as English and Scandinavian....

Alternatives generation and analysis report for immobilized low-level waste interim storage architecture

Energy Technology Data Exchange (ETDEWEB)

Burbank, D.A., Westinghouse Hanford

1996-09-01

The Immobilized Low-Level Waste Interim Storage subproject will provide storage capacity for immobilized low-level waste product sold to the U.S. Department of Energy by the privatization contractor. This report describes alternative Immobilized Low-Level Waste storage system architectures, evaluation criteria, and evaluation results to support the Immobilized Low-Level Waste storage system architecture selection decision process.

Diatomite Modified Immobilized Delftia sp. for the Bio-Abiotic Removal of Antibiotics Amoxicillin in the Aqueous System

Science.gov (United States)

Gao, Lijuan; Sun, Jing; Guan, Kai; Shen, Tingting; Wang, Xikui

2017-05-01

Diatomite modified sodium alginate (Si/SA) immobilized Delftia sp. A2(2011) (STT01) was applied to degrade amoxicillin. The immobilized pellets provided a direct and visual probe for the degradation process due to their intrinsic bright colour. The results demonstrated that 100% of amoxicillin and 68.5% of CODcr removal were achieved after 72 h, comparing with the cases of sodium alginate (SA) system (81.2%, 46.9%) and the free cells system (60.5%, 35.5%). The degradation kinetics was in good agreement with Michaelis-Menten equation. The maximum rate (Vm ) and Michaelis constant (Km ) were calculated as 9.09 mg L-1 h-1 and 228 mg L-1, respectively. The results further revealed that diatomite not only acted as immobilization support to improve the mechanical strength and lifetime of the pellets but also as absorbent to promote the treatment efficiency. Therefore, both enzymatic catalysis and chemisorption were responsible for the removal of amoxicillin.

Immobilization of microbial cells: A promising tool for treatment of ...

African Journals Online (AJOL)

The review articles on cell immobilization have been published since 1980 and reflect the general interest in this topic. Immobilized microbial cells create opportunities in a wide range of sectors including environmental pollution control. Compared with suspended microorganism technology, cell immobilization shows many ...

Immobilization patterns and dynamics of acetate-utilizing methanogens immobilized in sterile granular sludge in upflow anaerobic sludge blanket reactors

DEFF Research Database (Denmark)

Schmidt, Jens Ejbye; Ahring, Birgitte Kiær

1999-01-01

Sterile granular sludge was inoculated with either Methanosarcina mazeii S-6, Methanosaeta concilii GP-6, or both species in acetate-fea upflow anaerobic sludge blanket (UASB) reactors to investigate the immobilization patterns and dynamics of aceticlastic methanogens in granular sludge. After......, but where the acetate concentration was low this strain was immobilized on support material as single cells or small clumps, The data clearly show that the two aceticlastic methanogens immobilize differently in UASB systems, depending on the conditions found throughout the UASB reactor....

Statement of work for the immobilized high-level waste transportation system, Project W-464

Energy Technology Data Exchange (ETDEWEB)

Mouette, P.

1998-06-24

The objective of this Statement of Work (SOW) is to present the scope, the deliverables, the organization, the technical and schedule expectations for the development of a Package Design Criteria (PDC), cost and schedule estimate for the acquisition of a transportation system for the Immobilized High-Level Waste (IHLW). This transportation system which includes the truck, the trailer, and a shielded cask will be used for on-site transportation of the IHLW canisters from the private vendor vitrification facility to the Hanford Site interim storage facility, i.e., vaults 2 and 3 of the Canister Storage Building (CSB). This Statement of Work asks Waste Management Federal Services, Inc., Northwest Operations, to provide Project W-464 with a Design Criteria Document, plus a life-cycle schedule and cost estimate for the acquisition of a transportation system (shielded cask, truck, trailer) for IHLW on-site transportation.

Cobalt immobilization by manganese oxidizing bacteria from the Indian ridge system

Digital Repository Service at National Institute of Oceanography (India)

Antony, R.; Sujith, P.P.; Fernandes, S.O.; Verma, P.; Khedekar, V.D.; LokaBharathi, P.A.

Co immobilization by two manganese oxidizing isolates from Carlsberg Ridge waters (CR35 and CR48) was compared with that of Mn at same molar concentrations. At a lower concentration of 10 mu M, CR35 and CR48 immobilized 22 and 23 fM Co cell-1...

Immobilization of Isolated Lipase From Moldy Copra (Aspergillus Oryzae

Directory of Open Access Journals (Sweden)

Seniwati Dali

2011-01-01

Full Text Available Enzyme immobilization is a recovery technique that has been studied in several years, using support as a media to help enzyme dissolutions to the reaction substrate. Immobilization method used in this study was adsorption method, using specific lipase from Aspergillus oryzae. Lipase was partially purified from the culture supernatant of Aspergillus oryzae. Enzyme was immobilized by adsorbed on silica gel. Studies on free and immobilized lipase systems for determination of optimum pH, optimum temperature, thermal stability and reusability were carried out. The results showed that free lipase had optimum pH 8,2 and optimum temperature 35 °C while the immobilized lipase had optimum 8,2 and optimum temperature 45 °C. The thermal stability of the immobilized lipase, relative to that of the free lipase, was markedly increased. The immobilized lipase can be reused for at least six times.

Immobilization of microorganisms. Part 1. Preparation of immobilized Lactobacillus bulgaricus

Energy Technology Data Exchange (ETDEWEB)

Lee, K H

1981-01-01

The immobilization of Lactobacillus bulgaricus on polyacrylamide and on alginate beads was investigated. The most active immobilized cells were obtained by entrapment in Ca alginate beads. These immobilized microbial cells, when introduced into 4.5% lactose solution and whey solution showed maximum relative activity of 28% for lactose and 18% for whey compared to free cells.

Immobilization of defense high-level waste: an assessment of technological strategies and potential regulatory goals. Volume I

International Nuclear Information System (INIS)

1979-06-01

An investigation was made of the high-level radioactive waste immobilization technology programs in the U.S. and Europe, and of the associated regulatory programs and waste management perspectives in the countries studied. Purpose was to assess the ability of those programs to satisfy DOE waste management needs and U.S. regulatory requirements. This volume includes: introduction, immobilization strategies in the context of waste isolation program needs, high-level waste management as an integrated system, regulatory goals, engineered-barrier characteristics, barrier technology, high-level waste disposal programs, analysis of HLW immobilization technology in the context of policy and regulatory requirements, and waste immobilization program option

Uranium uptake by immobilized cells of Pseudomonas strain EPS 5028

International Nuclear Information System (INIS)

Pons, M.P.; Fuste, M.C.

1993-01-01

Polyacrylamide-gel-immobilized cells of Pseudomonas strain EPS 5028 were effective in the removal of uranium (U) from synthetic effluents. Metal accumulation was performed in an open system in columns filled with immobilized cells that were challenged with continuous flows containing U. Possible variable of the system were studied. Uranium uptake by the immobilized cells of this microorganism was affected by pH but not by temperature or flow rate. In addition, U binding could be interpreted in terms of the Freundlich adsorption isotherm indicating single-layer adsorption. The feasibility of reusing the immobilized cells was suggested after the recovery of U with a solution of 0.1 M sodium carbonate. (orig.)

High-level-waste immobilization

International Nuclear Information System (INIS)

Crandall, J.L.

1982-01-01

Analysis of risks, environmental effects, process feasibility, and costs for disposal of immobilized high-level wastes in geologic repositories indicates that the disposal system safety has a low sensitivity to the choice of the waste disposal form

Platform for immobilization and observation of subcellular processes

Science.gov (United States)

McKnight, Timothy E.; Kalluri, Udaya C.; Melechko, Anatoli V.

2014-08-26

A method of immobilizing matter for imaging that includes providing an array of nanofibers and directing matter to the array of the nanofibers. The matter is immobilized when contacting at least three nanofibers of the array of nanofibers simultaneously. Adjacent nanofibers in the array of nanofibers may be separated by a pitch as great as 100 microns. The immobilized matter on the array of nanofibers may then be imaged. In some examples, the matter may be cell matter, such as protoplasts.

Physical immobilization of biofunctional substance by the use of radiation polymerization

International Nuclear Information System (INIS)

Kobayashi, M.; Kaetsu, I.

1982-01-01

Radiation-induced polymerization at low temperatures of glass-forming monomers in a supercooled state can be applied, for example, in casting of organic glass and the immobilization of biofunctional substance. The immobilization of various biofunctional materials such as enzymes, microbial cells, tissue cells etc. will be a promising application in the near future in biotechnology and bioengineering. The authors studied the immobilization technique which can be applied to general biocomponents, by using low-temperature radiation polymerization in a supercooled phase. According to this method, biocomponents are composed mainly on the surface of the carrier polymer, and therefore the product has the bioactivity at the surface of the composite. This method can be called the adhesion method. Biocomponents can be composed simply by mixing with monomer, shaping into a desirable form, then cooling to low temperature and irradiating into a product. On the cooling of the monomer-buffer (including biocomponent) mixture, water in the buffer changes to ice and then the biocomponents in the buffer are isolated from the ice, and concentrated on a surface of supercooled monomer phase. These biocomponents are fixed immediately on the polymer surface by irradiation. Anti-cancers immobilized by low-temperature radiation-induced polymerization have been applied to local chemotherapy by implantation, and the result of such a slow release system has been proved to be successful by animal experiments. The application of the radiation immobilized antibody to immunoassay has also been proved successful. The authors started research on the utilization of radiation techniques for the conversion of cellulosic wastes such as chaff, rice straw, sawdust, bagasse and wastepaper. It includes pretreatment by irradiation of cellulose wastes and saccharification and fermentation by using radiation immobilized enzymes and yeasts. (author)

Excess Weapons Plutonium Immobilization in Russia

International Nuclear Information System (INIS)

Jardine, L.; Borisov, G.B.

2000-01-01

The joint goal of the Russian work is to establish a full-scale plutonium immobilization facility at a Russian industrial site by 2005. To achieve this requires that the necessary engineering and technical basis be developed in these Russian projects and the needed Russian approvals be obtained to conduct industrial-scale immobilization of plutonium-containing materials at a Russian industrial site by the 2005 date. This meeting and future work will provide the basis for joint decisions. Supporting R and D projects are being carried out at Russian Institutes that directly support the technical needs of Russian industrial sites to immobilize plutonium-containing materials. Special R and D on plutonium materials is also being carried out to support excess weapons disposition in Russia and the US, including nonproliferation studies of plutonium recovery from immobilization forms and accelerated radiation damage studies of the US-specified plutonium ceramic for immobilizing plutonium. This intriguing and extraordinary cooperation on certain aspects of the weapons plutonium problem is now progressing well and much work with plutonium has been completed in the past two years. Because much excellent and unique scientific and engineering technical work has now been completed in Russia in many aspects of plutonium immobilization, this meeting in St. Petersburg was both timely and necessary to summarize, review, and discuss these efforts among those who performed the actual work. The results of this meeting will help the US and Russia jointly define the future direction of the Russian plutonium immobilization program, and make it an even stronger and more integrated Russian program. The two objectives for the meeting were to: (1) Bring together the Russian organizations, experts, and managers performing the work into one place for four days to review and discuss their work with each other; and (2) Publish a meeting summary and a proceedings to compile reports of all the

Biosorption of uranium by immobilized cells of Rhodotorula glutinis

International Nuclear Information System (INIS)

Jing Bai; Zhan Li; Fangli Fan; Xiaolei Wu; Xiaojie Yin; Longlong Tian; Zhi Qin; Junsheng Guo

2014-01-01

Biosorption of uranium ions from diluted solution (≤40 mg L -1 ) onto immobilized cells of Rhodotorula glutinis was investigated in a batch system. Equilibrium, kinetic and thermodynamic studies were conducted by considering the effect of initial uranium concentration, contact time and temperature. Non-linear forms of Langmuir, Freundlich and Sips isotherm models were used to fit the equilibrium data, Sips model was designated as the best one. Kinetic data were simulated by non-linear pseudo-first-order, pseudo-second-order and intra-particle diffusion equations. Pseudo-first-order kinetic equation described the experimental data better than pseudo-second-order equation and intra-particle diffusion equation can fit the kinetic data with two independent curves. Thermodynamic parameters, including ∆H 0, ∆G 0 and ∆S 0, were evaluated, the sorption process was determined to be spontaneous and endothermic. Uranium sorption from pure uranium solutions and uranium pit wastewater by immobilized biomass and blank beads, as well as the regeneration results indicated that immobilized R. glutinis can be use to recovery uranium from uranium pit wastewater. (author)

Catalytical Properties of Free and Immobilized Aspergillus niger Tannase

OpenAIRE

Abril Flores-Maltos; Luis V. Rodríguez-Durán; Jacqueline Renovato; Juan C. Contreras; Raúl Rodríguez; Cristóbal N. Aguilar

2011-01-01

A fungal tannase was produced, recovered, and immobilized by entrapment in calcium alginate beads. Catalytical properties of the immobilized enzyme were compared with those of the free one. Tannase was produced intracellularly by the xerophilic fungus Aspergillus niger GH1 in a submerged fermentation system. Enzyme was recovered by cell disruption and the crude extract was partially purified. The catalytical properties of free and immobilized tannase were evaluated using tannic acid and methy...

Lipase immobilization and production of fatty acid methyl esters from canola oil using immobilized lipase

International Nuclear Information System (INIS)

Yuecel, Yasin; Demir, Cevdet; Dizge, Nadir; Keskinler, Buelent

2011-01-01

Lipase enzyme from Aspergillus oryzae (EC 3.1.1.3) was immobilized onto a micro porous polymeric matrix which contains aldehyde functional groups and methyl esters of long chain fatty acids (biodiesel) were synthesized by transesterification of crude canola oil using immobilized lipase. Micro porous polymeric matrix was synthesized from styrene-divinylbenzene (STY-DVB) copolymers by using high internal phase emulsion technique and two different lipases, Lipozyme TL-100L ® and Novozym 388 ® , were used for immobilization by both physical adsorption and covalent attachment. Biodiesel production was carried out with semi-continuous operation. Methanol was added into the reactor by three successive additions of 1:4 M equivalent of methanol to avoid enzyme inhibition. The transesterification reaction conditions were as follows: oil/alcohol molar ratio 1:4; temperature 40 o C and total reaction time 6 h. Lipozyme TL-100L ® lipase provided the highest yield of fatty acid methyl esters as 92%. Operational stability was determined with immobilized lipase and it indicated that a small enzyme deactivation occurred after used repeatedly for 10 consecutive batches with each of 24 h. Since the process is yet effective and enzyme does not leak out from the polymer, the method can be proposed for industrial applications. -- Research highlights: → Lipozyme TL-100L and Novozym 388 were immobilized onto micro porous polymeric matrix by both physical adsorption and covalent linking. → Immobilized enzymes were used for synthesis of fatty acid methyl esters by transesterification of canola oil and methanol using semi-continuous operation system. → According to chromatographic analysis, Lipase Lipozyme TL-100L resulted in the highest yield of methyl ester as 92%.

Implementation and validation of a new fixation system for stereotactic radiation therapy: An analysis of patient immobilization.

Science.gov (United States)

Lang, Stephanie; Linsenmeier, Claudia; Brown, Michelle L; Cavelaars, Frederique; Tini, Alessandra; Winter, Christopher; Krayenbuehl, Jerome

2015-01-01

Stereotactic radiation therapy is an established treatment technique for intracranial malignancies. We evaluated a new intracranial immobilization system with an emphasis on determining the intrafraction motion and the correlation of this motion with treatment time. Patients were immobilized using the trUpoint ARCH fixation system (CIVCO Medical Solutions). We collected data from 85 lesions in 73 patients treated between November 2011 and December 2013. Sixty-nine of 73 patients (95%) used the complete mask system; for the remaining 4 patients, the system had to be adapted. Patients were treated using volumetric modulated arc therapy stereotactic radiation therapy on a TrueBeam linear accelerator (Varian Medical Systems, Palo Alto, CA). Fraction doses of 2-8 Gy were applied in 4-30 fractions. Daily cone beam computed tomography imaging was performed before the treatment and was matched to the reference computed tomography using a 6-degrees-of-freedom automatching procedure. Additionally, posttreatment cone beam computed tomography scans were performed to assess intrafraction motion for 67 patients (375 fractions). The average 3-dimensional setup error was 2.1 ± 2.9 mm. The mean pitch and roll was -0.1 ± 0.7° and 0.2 ± 0.7°. A total of 98.0% of the pitch values and 98.9% of the roll values were immobilization system appears to be robust in terms of setup accuracy, intrafraction motion, and repositioning of the mask system. Copyright © 2015 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Immobilization of lipase on sepabeads and its application in pentyl octanoate synthesis in a low aqueous system

Directory of Open Access Journals (Sweden)

Knežević-Jugović Zorica D.

2008-01-01

Full Text Available The object of the study was to investigate the process conditions relevant for the pentyl octanoate production with the lipase from Candida rugosa immobilized on Sepabeads EC-EP carrier. This is an epoxide-containing commercial polymethacrylic carrier with suitable characteristics for enzyme immobilization. The immobilized lipase suitable for pentyl octanoate synthesis has been prepared by a direct lipase binding to polymers via their epoxide groups. The enzymatic activity was determined by both hydrolysis of olive oil in an aqueous system and esterification of n-pentanol with octanoic acid in a low aqueous system. The influence of several important reaction parameters such as temperature, initial water content, initial substrate molar ratio, enzyme loading and time of adding of molecular sieves in the system is carefully analyzed by means of an experimental design. Production of the ester was optimized and an ester production response equation was obtained, making it possible to predict ester yields from known values of the five main factors. Almost complete conversion (>99% of the substrate to ester could be realized, using lipase loading as low as 37 mg/g dry support and in a relatively short time (24 h at 45ºC, when high initial substrate molar ratio of 2.2 is used.

Treatment and immobilization of intermediate-level radioactive wastes

International Nuclear Information System (INIS)

Lerch, R.E.; Greenhalgh, W.O.; Partridge, J.A.; Richardson, G.L.

1979-01-01

A new program underway at the Hanford Engineering Development Laboratory (HEDL) to develop and demonstrate treatment and immobilization technologies for intermediate-level wastes (ILW) generated in the nuclear fuel cycle is discussed. ILW are defined as those liquid and solid radioactive wastes, other than high-level wastes and fuel cladding hulls, that in packaged form have radiation dose readings greater than 200 millirem/hr at the packaged surface and 10 millirem/hr at three feet from the surface. The IAEA value of 10 4 Ci/m 3 for ILW defines the upper limit. For comparative purposes, reference is also made to certain aspects of low-level radioactive wastes (LLW). Initial work has defined the sources, quantities and types of wastes which comprise ILW. Because of the wide differences in composition (e.g., acids, salt solutions, resins and zeolites, HEPA filters, etc.) the wastes may require different treatments, particularly those wastes containing volatile contaminants. The various types of ILW have been grouped into categories amenable to similar treatment. Laboratory studies are underway to define treatment technologies for liquid ILW which contain volatile contaminants and to define immobilization parameters for the residues resulting from treatment of ILW. Immobilization agents initially being evaluated for the various residues include cement, urea-formaldehyde, and bitumen although other immobilization agents will be studied. The program also includes development of acceptable test procedures for the final immobilized products as well as development of proposed criteria for storage, transportation, and disposal of the immobilized ILW

Radiation technology for immobilization of bioactive materials

International Nuclear Information System (INIS)

1988-12-01

Within the framework of the Agency's coordinated research programme on ''Application of Radiation Technology in Immobilization of Bioactive Materials'', the third and final research coordination meeting was held at Beijing University, Beijing, People's Republic of China, 15-18 June 1987. The present publication compiles all presentations made at the meeting. Fundamental processes for the immobilization of enzymes, antibodies, cells and drugs were developed and established using gamma radiation, electron beams and plasma discharge. Applications of various biofunctional components, immobilized by radiation techniques in different processes, were studied. A range of backbone polymers has been examined together with various monomers. Coupling procedures have been developed which are relevant to our particular requirements. Enzymes of various types and characteristics have been immobilized with considerable efficiency. The immobilized biocatalysts have been shown to possess significant activity and retention of activity on storage. There appears to be a high degree of specificity associated with the properties of the immobilised biocatalysts, their activity and the ease of their preparation. Novel additives which lower the total radiation dose in grafting have been discovered and their value in immobilization processes assessed. Potential applications include: medical (diagnostic, therapeutic), and industrial processes (fermentation, bioseparation, etc.). Refs, figs and tabs

Degradation of phenol and TCE using suspended and chitosan-bead immobilized Pseudomonas putida.

Science.gov (United States)

Chen, Yan-Min; Lin, Tsair-Fuh; Huang, Chih; Lin, Jui-Che; Hsieh, Feng-Ming

2007-09-30

The degradability of phenol and trichloroethene (TCE) by Pseudomonas putida BCRC 14349 in both suspended culture and immobilized culture systems are investigated. Chitosan beads at a size of about 1-2mm were employed to encapsulate the P. putida cells, becoming an immobilized culture system. The phenol concentration was controlled at 100 mg/L, and that of TCE was studied from 0.2 to 20 mg/L. The pH, between 6.7 and 10, did not affect the degradation of either phenol or TCE in the suspended culture system. However, it was found to be an important factor in the immobilized culture system in which the only significant degradation was observed at pH >8. This may be linked to the surface properties of the chitosan beads and its influence on the activity of the bacteria. The transfer yield of TCE on a phenol basis was almost the same for the suspended and immobilized cultures (0.032 mg TCE/mg phenol), except that these yields occurred at different TCE concentrations. The transfer yield at a higher TCE concentration for the immobilized system suggested that the cells immobilized in carriers can be protected from harsh environmental conditions. For kinetic rate interpretation, the Monod equation was employed to describe the degradation rates of phenol, while the Haldane's equation was used for TCE degradation. Based on the kinetic parameters obtained from the two equations, the rate for the immobilized culture systems was only about 1/6 to that of the suspended culture system for phenol degradation, and was about 1/2 for TCE degradation. The slower kinetics observed for the immobilized culture systems was probably due to the slow diffusion of substrate molecules into the beads. However, compared with the suspended cultures, the immobilized cultures may tolerate a higher TCE concentration as much less inhibition was observed and the transfer yield occurred at a higher TCE concentration.

Surface functionalization of superparamagnetic nanoparticles encapsulated by chitosan for protein immobilization

International Nuclear Information System (INIS)

Sousa, Jose Silva de

2010-01-01

Nanoscience and nanotechnology have opened up numerous developments of devices and systems on the nanometer scale, with new molecular organization, properties and functions. In this context, the polymeric magnetic nanoparticles are composites formed by magnetic materials with a particle size between 1 and 100 nm combined with functional polymers. They are well-known and have been widely studied because of its applications in various technology areas. Applications on the biological and medical areas include separation and immobilization of enzymes and proteins, improved techniques of magnetic resonance imaging and diagnostic systems for controlled drug delivery. In this work, proteins were immobilized on the surface of a biopolymer combined with superparamagnetic particles of magnetite. The biopolymer chitosan was used, cross-linked and functionalized with glutaraldehyde, applicable to the biological assays. Three types of magnetic composites were obtained, which were called QM1Glu, QM2NaGlu and QM3Glu. They were characterized by X-ray diffraction, scanning electron microscopy, vibrating sample magnetometry, differential scanning calorimetry, thermogravimetry and infrared spectroscopy. They were evaluated concerning the immobilization of the proteins bovine serum albumin (BSA), collagen and trypsin. The study showed that the immobilization of proteins on the biopolymer occurred in 30 min of incubation. The magnetic composite of non functionalized chitosan (QM3) was also evaluated. For trypsin, it was found that the immobilization potential of QM3 was higher than that observed for QM3Glu. After 30 days, the trypsin of the QM3-Trip and QM3Glu-Trip was still with activity. The activity and the enzyme kinetics of the QM3Glu-Trip with the substrate BApNA were demonstrated. (author)

Site-Selective Orientated Immobilization of Antibodies and Conjugates for Immunodiagnostics Development

Science.gov (United States)

Rusling, James

2016-01-01

Immobilized antibody systems are the key to develop efficient diagnostics and separations tools. In the last decade, developments in the field of biomolecular engineering and crosslinker chemistry have greatly influenced the development of this field. With all these new approaches at our disposal, several new immobilization methods have been created to address the main challenges associated with immobilized antibodies. Few of these challenges that we have discussed in this review are mainly associated to the site-specific immobilization, appropriate orientation, and activity retention. We have discussed the effect of antibody immobilization approaches on the parameters on the performance of an immunoassay. PMID:27876681

Co-immobilized Coupled Enzyme Systems in Biotechnology

Science.gov (United States)

2010-01-01

coimmobilized by ~n­ capsulation in silica spheres that were formed by a polymer -templated silicificatiOn reaction (Betancor et al., 2006). Nitrobenzene...F. , FERNANDEZ-LAFUENTE, R. , GUISAN J. M. (2005). Stabilization of enzymes by multipoint immobilization of thiolated proteins on new epoxy-thiol... polymer monoliths in microftuidic devices for steady- state kinetic analysis and spatially separated multi-enzyme reactions. Analytical Chemistry, 79

Enzyme Engineering for In Situ Immobilization.

Science.gov (United States)

Rehm, Fabian B H; Chen, Shuxiong; Rehm, Bernd H A

2016-10-14

Enzymes are used as biocatalysts in a vast range of industrial applications. Immobilization of enzymes to solid supports or their self-assembly into insoluble particles enhances their applicability by strongly improving properties such as stability in changing environments, re-usability and applicability in continuous biocatalytic processes. The possibility of co-immobilizing various functionally related enzymes involved in multistep synthesis, conversion or degradation reactions enables the design of multifunctional biocatalyst with enhanced performance compared to their soluble counterparts. This review provides a brief overview of up-to-date in vitro immobilization strategies while focusing on recent advances in enzyme engineering towards in situ self-assembly into insoluble particles. In situ self-assembly approaches include the bioengineering of bacteria to abundantly form enzymatically active inclusion bodies such as enzyme inclusions or enzyme-coated polyhydroxyalkanoate granules. These one-step production strategies for immobilized enzymes avoid prefabrication of the carrier as well as chemical cross-linking or attachment to a support material while the controlled oriented display strongly enhances the fraction of accessible catalytic sites and hence functional enzymes.

Halloysite Clay Nanotubes for Enzyme Immobilization.

Science.gov (United States)

Tully, Joshua; Yendluri, Raghuvara; Lvov, Yuri

2016-02-08

Halloysite clay is an aluminosilicate nanotube formed by rolling flat sheets of kaolinite clay. They have a 15 nm lumen, 50-70 nm external diameter, length of 0.5-1 μm, and different inside/outside chemistry. Due to these nanoscale properties, they are used for loading, storage, and controlled release of active chemical agents, including anticorrosions, biocides, and drugs. We studied the immobilization in halloysite of laccase, glucose oxidase, and lipase. Overall, negatively charged proteins taken above their isoelectric points were mostly loaded into the positively charged tube's lumen. Typical tube loading with proteins was 6-7 wt % from which one-third was released in 5-10 h and the other two-thirds remained, providing enhanced biocatalysis in nanoconfined conditions. Immobilized lipase showed enhanced stability at acidic pH, and the optimum pH shifted to more alkaline pH. Immobilized laccase was more stable with respect to time, and immobilized glucose oxidase showed retention of enzymatic activity up to 70 °C, whereas the native sample was inactive.

Immobilization of oligonucleotide probes on silicon surfaces using biotin–streptavidin system examined with microscopic and spectroscopic techniques

Energy Technology Data Exchange (ETDEWEB)

Awsiuk, K., E-mail: kamil.awsiuk@uj.edu.pl [M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, Kraków 30-059 (Poland); Rysz, J. [M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, Kraków 30-059 (Poland); Petrou, P. [Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety, NCSR “Demokritos”, End Patriarchou Gregoriou Str., Aghia Paraskevi 15310 (Greece); Budkowski, A. [M. Smoluchowski Institute of Physics, Jagiellonian University, Reymonta 4, Kraków 30-059 (Poland); Bernasik, A. [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, Kraków 30-059 (Poland); Kakabakos, S. [Institute of Nuclear and Radiological Sciences and Technology, Energy and Safety, NCSR “Demokritos”, End Patriarchou Gregoriou Str., Aghia Paraskevi 15310 (Greece); Marzec, M.M. [Faculty of Physics and Applied Computer Science, AGH-University of Science and Technology, Al. Mickiewicza 30, Kraków 30-059 (Poland); Raptis, I. [Institute for Advanced Materials, Physicochemical Processes, Nanotechnology and Microsystems, NCSR “Demokritos”, End Patriarchou Gregoriou Str., Aghia Paraskevi 15310 (Greece)

2014-01-30

To immobilize effectively oligonucleotide probes on SiO{sub 2} modified with (3-aminopropyl)triethoxysilane, four procedures based on streptavidin–biotin system are compared with Atomic Force Microscopy, Angle-Resolved X-ray Photoelectron Spectroscopy and Time-of-Flight Secondary Ion Mass Spectrometry. The first approach involves: adsorption of biotinylated Bovine Serum Albumin, blocking free surface sites with BSA, binding of streptavidin and biotinylated oligonucleotide (b-oligo). Final steps are exchanged in the second procedure with immobilization of preformed streptavidin–b-oligo conjugate. The third approach consists of streptavidin adsorption, blocking with BSA and b-oligo binding. Finally, streptavidin–b-oligo conjugate is immobilized directly within the fourth method. Surface coverage with biomolecules, determined from ARXPS, accords with average AFM height, and is anti-correlated with the intensity of Si+ ions. Higher biomolecular coverage was achieved during the last steps of the first (2.45(±0.38) mg/m{sup 2}) and second (1.31(±0.22) mg/m{sup 2}) approach, as compared to lower surface density resulting from the third (0.58(±0.20) mg/m{sup 2}) and fourth (0.41(±0.11) mg/m{sup 2}) method. Phosphorus atomic concentration indicates effectiveness of oligonucleotide immobilization. Secondary ions intensities, characteristic for oligonucleotides, streptavidin, BSA, and proteins, allow additional insight into overlayer composition. These measurements verify the ARXPS results and show the superiority of the first two immobilization approaches in terms of streptavidin and oligonucleotide density achieved onto the surface.

Immobilization of oligonucleotide probes on silicon surfaces using biotin–streptavidin system examined with microscopic and spectroscopic techniques

International Nuclear Information System (INIS)

Awsiuk, K.; Rysz, J.; Petrou, P.; Budkowski, A.; Bernasik, A.; Kakabakos, S.; Marzec, M.M.; Raptis, I.

2014-01-01

To immobilize effectively oligonucleotide probes on SiO 2 modified with (3-aminopropyl)triethoxysilane, four procedures based on streptavidin–biotin system are compared with Atomic Force Microscopy, Angle-Resolved X-ray Photoelectron Spectroscopy and Time-of-Flight Secondary Ion Mass Spectrometry. The first approach involves: adsorption of biotinylated Bovine Serum Albumin, blocking free surface sites with BSA, binding of streptavidin and biotinylated oligonucleotide (b-oligo). Final steps are exchanged in the second procedure with immobilization of preformed streptavidin–b-oligo conjugate. The third approach consists of streptavidin adsorption, blocking with BSA and b-oligo binding. Finally, streptavidin–b-oligo conjugate is immobilized directly within the fourth method. Surface coverage with biomolecules, determined from ARXPS, accords with average AFM height, and is anti-correlated with the intensity of Si+ ions. Higher biomolecular coverage was achieved during the last steps of the first (2.45(±0.38) mg/m 2 ) and second (1.31(±0.22) mg/m 2 ) approach, as compared to lower surface density resulting from the third (0.58(±0.20) mg/m 2 ) and fourth (0.41(±0.11) mg/m 2 ) method. Phosphorus atomic concentration indicates effectiveness of oligonucleotide immobilization. Secondary ions intensities, characteristic for oligonucleotides, streptavidin, BSA, and proteins, allow additional insight into overlayer composition. These measurements verify the ARXPS results and show the superiority of the first two immobilization approaches in terms of streptavidin and oligonucleotide density achieved onto the surface.

Limb immobilization and corticobasal syndrome.

Science.gov (United States)

Graff-Radford, Jonathan; Boeve, Bradley F; Drubach, Daniel A; Knopman, David S; Ahlskog, J Eric; Golden, Erin C; Drubach, Dina I; Petersen, Ronald C; Josephs, Keith A

2012-12-01

Recently, we evaluated two patients with corticobasal syndrome (CBS) who reported symptom onset after limb immobilization. Our objective was to investigate the association between trauma, immobilization and CBS. The charts of forty-four consecutive CBS patients seen in the Mayo Clinic Alzheimer Disease Research Center were reviewed with attention to trauma and limb immobilization. 10 CBS patients (23%) had immobilization or trauma on the most affected limb preceding the onset or acceleration of symptoms. The median age at onset was 61. Six patients manifested their first symptoms after immobilization from surgery or fracture with one after leg trauma. Four patients had pre-existing symptoms of limb dysfunction but significantly worsened after immobilization or surgery. 23 percent of patients had immobilization or trauma of the affected limb. This might have implications for management of CBS, for avoiding injury, limiting immobilization and increasing movement in the affected limb. Copyright © 2012 Elsevier Ltd. All rights reserved.

Atrazine dissipation in a biobed system inoculated with immobilized white-rot fungi

OpenAIRE

Elgueta, Sebastian; Santos, Cledir; Santos, C.; Lima, Nelson; Diez, M. C.

2016-01-01

Due to the environmental concerns about the herbicide atrazine accumulation in food products and water reservoirs, there is a need to develop safe and economical methods for its dissipation. The main aim of this study was to evaluate the atrazine dissipation in a biobed system inoculated with immobilized white-rot fungi in a pelletized support (PS). All fungal isolates evaluated were efficient in colonizing the surface and inner parts of the PS and without differences observed in the coloniza...

Immobilization of l-Asparaginase on Carrier Materials: A Comprehensive Review.

Science.gov (United States)

Ulu, Ahmet; Ates, Burhan

2017-06-21

There are two major applications of l-asparaginase (L-ASNase): leukemia therapy and the food industry. Especially, its chemotherapeutic effect has attracted interest from the scientific community and individual scientists. Therefore, to protect the intrinsic activity and half-time of L-ASNase, several carriers and immobilization techniques for immobilization of L-ASNase have been described in articles. Unfortunately, a comprehensive review about immobilization of L-ASNase has not been written until now. In this review, we have thoroughly discussed the carriers for L-ASNase by illustrating immobilization findings including both past and present applications. In addition, we have revealed advantages and disadvantages of immobilized enzyme and related it to free form. We believe that this review will not only provide background information, but also guide future developments.

Immobilization technology for krypton in amorphous zeolite

International Nuclear Information System (INIS)

Takusagawa, Atsushi; Ishiyama, Keiichi

1989-01-01

Radioactive krypton recovered from the offgas of a reprocessing plant requires long-term storage on the order of 100 years. Immobilization technology for krypton into amorphous zeolite 5A is considered one of the best methods for long-term storage. In this report, conditions for immobilization treatment and stability of amorphous zeolite 5A loaded krypton against heat, radiation and water are discussed, and a treatment system using this technology is described. (author)

Diesel oil removal by immobilized Pseudoxanthomonas sp. RN402.

Science.gov (United States)

Nopcharoenkul, Wannarak; Netsakulnee, Parichat; Pinyakong, Onruthai

2013-06-01

Pseudoxanthomonas sp. RN402 was capable of degrading diesel, crude oil, n-tetradecane and n-hexadecane. The RN402 cells were immobilized on the surface of high-density polyethylene plastic pellets at a maximum cell density of 10(8) most probable number (MPN) g(-1) of plastic pellets. The immobilized cells not only showed a higher efficacy of diesel oil removal than free cells but could also degrade higher concentrations of diesel oil. The rate of diesel oil removal by immobilized RN402 cells in liquid culture was 1,050 mg l(-1) day(-1). Moreover, the immobilized cells could maintain high efficacy and viability throughout 70 cycles of bioremedial treatment of diesel-contaminated water. The stability of diesel oil degradation in the immobilized cells resulted from the ability of living RN402 cells to attach to material surfaces by biofilm formation, as was shown by CLSM imaging. These characteristics of the immobilized RN402 cells, including high degradative efficacy, stability and flotation, make them suitable for the purpose of continuous wastewater bioremediation.

Application and use of spinal immobilization devices in zero-gravity flight

Science.gov (United States)

Krupa, Debra T.; Gosbee, John; Billica, Roger; Boyce, Joey B.

1991-01-01

A KC-135 parabolic flight was performed for the purpose of evaluation of spinal immobilization techniques in microgravity. The flight followed the standard 40 parabola profile with four NASA/KRUG experimenters involved. One performed as coordinator/recorder, one as test subject, and two as the Crew Medical Officers (CMO). The flight was to evaluate the application of spinal immobilization devices and techniques in microgravity as are performed during initial stabilization or patient transport scenarios. The sequence of detail for examination of the following objectives included: attempted cervical spine immobilization with all free floating, the patient restrained to the floor, various hand positioning techniques; c-collar placement; Kendrick Extrication Device (KED) application with various restraints for patient and CMO; patient immobilization and transport using the KED; patient transported on KED and spine board. Observations for each task are included. Major conclusions and issues are also included.

Immobilization of acid digestion residue

International Nuclear Information System (INIS)

Greenhalgh, W.O.; Allen, C.R.

1983-01-01

Acid digestion treatment of nuclear waste is similar to incineration processes and results in the bulk of the waste being reduced in volume and weight to some residual solids termed residue. The residue is composed of various dispersible solid materials and typically contains the resultant radioactivity from the waste. This report describes the immobilization of the residue in portland cement, borosilicate glass, and some other waste forms. Diagrams showing the cement and glass virtification parameters are included in the report as well as process steps and candidate waste product forms. Cement immobilization is simplest and probably least expensive; glass vitrification exhibits the best overall volume reduction ratio

Plutonium Immobilization Can Loading Conceptual Design

Energy Technology Data Exchange (ETDEWEB)

Kriikku, E.

1999-05-13

'The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses the Plutonium Immobilization can loading conceptual design and includes a process block diagram, process description, preliminary equipment specifications, and several can loading issues. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.'

Plutonium Immobilization Can Loading Conceptual Design

International Nuclear Information System (INIS)

Kriikku, E.

1999-01-01

'The Plutonium Immobilization Facility will encapsulate plutonium in ceramic pucks and seal the pucks inside welded cans. Remote equipment will place these cans in magazines and the magazines in a Defense Waste Processing Facility (DWPF) canister. The DWPF will fill the canister with glass for permanent storage. This report discusses the Plutonium Immobilization can loading conceptual design and includes a process block diagram, process description, preliminary equipment specifications, and several can loading issues. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.'

Butyl acetate synthesis using immobilized lipase in calcium alginate beads

International Nuclear Information System (INIS)

Mohd Zulkhairi Abdul Rahim; Lee, Pat M.; Lee, Kong H.

2008-01-01

The esterification reaction of acetic acid and n-butanol using immobilized lipase encapsulated in calcium alginate beads (Lipase - CAB) and in chitosan coated calcium alginate beads (Lipase-CCAB) in n-hexane under mild reaction conditions were studied. Effects of temperature and substrate concentration (acetic acid and n-butanol) using Lipase - CAB, Lipase - CCAB and free lipase on the esterification reaction and their thermal stability towards esterification reaction were investigated. Results of temperature studies showed that the butyl acetate conversion increased with increase of temperature and reached the highest yield of about 70% around 50 degree Celsius for both immobilized systems but the yield of product catalyzed by free enzyme decreased as temperature was increased. Thermal stabilities studies showed that the Lipase-CCAB and Lipase-CAB were stable throughout the temperature range of 30-60 degree Celsius. However, free lipase became less stable at temperatures higher than 50 degree Celsius. The substrates, n-butanol and acetic acid exerted different effects on the esterification reaction and the reaction was favoured by higher acetic acid concentration than butanol. Kinetics parameters, Km and Vmax values for both substrates and the specific activities of the three enzyme system were also determined. The beads morphology was examined using SEM. Batch-wise operational stability studies for both immobilized systems demonstrated that the immobilized lipase performed better in the batch wise reactor system than the continuous bioreactor system and that the immobilized lipase remained active for at least 5 cycles of batch wise esterification reactions. (author)

Pressure ulcers from spinal immobilization in trauma patients: a systematic review.

Science.gov (United States)

Ham, Wietske; Schoonhoven, Lisette; Schuurmans, Marieke J; Leenen, Luke P H

2014-04-01

To protect the (possibly) injured spine, trauma patients are immobilized on backboard or vacuum mattress, with a cervical collar, lateral headblocks, and straps. Several studies identified pressure ulcer (PU) development from these devices. The aim of this literature study was to gain insight into the occurrence and development of PUs, the risk factors, and the possible interventions to prevent PUs related to spinal immobilization with devices in adult trauma patients. We systematically searched PubMed (MEDLINE), EMBASE, Cochrane, and CINAHL for the period 1970 to September 2011. Studies were included if participants were healthy volunteers under spinal immobilization or trauma patients under spinal immobilization until spine injuries were diagnosed or excluded. Outcomes of primary interest included occurrence, severity, and risk for PU development as well as prevention of PU development related to spinal immobilization devices. The results of included studies show an incidence of collar-related PUs ranging from 6.8% to 38%. Described locations are the occiput, chin, shoulders, and back. The severity of these PUs varies between Stages 1 and 3, and one study describes PUs requiring surgical debridement, indicating a Stage 4 PU. Described risk factors for PU development are high pressure and pain from immobilizing devices, the length of time in/on a device, intensive care unit admission, high Injury Severity Scores (ISSs), mechanical ventilation, and intracranial pressure monitoring. Preventive interventions for collar-related PUs include early replacement of the extrication collar and regular skin assessment, collar refit, and position change. The results from this systematic review show that immobilization with devices increases the risk for PU development. This risk is demonstrated in nine experimental studies with healthy volunteers and in four clinical studies. Systematic review, level III.

Significance of membrane bioreactor design on the biocatalytic performance of glucose oxidase and catalase: Free vs. immobilized enzyme systems

DEFF Research Database (Denmark)

Morthensen, Sofie Thage; Meyer, Anne S.; Jørgensen, Henning

2017-01-01

Membrane separation of xylose and glucose can be accomplished via oxidation of glucose to gluconic acid by enzymatic glucose oxidase catalysis. Oxygen for this reaction can be supplied via decomposition of hydrogen peroxide by enzymatic catalase catalysis. In order to maximize the biocatalytic...... productivity of glucose oxidase and catalase (gluconic acid yield per total amount of enzyme) the following system set-ups were compared: immobilization of glucose oxidase alone; co-immobilization of glucose oxidase and catalase; glucose oxidase and catalase free in the membrane bioreactor. Fouling......-induced enzyme immobilization in the porous support of an ultrafiltration membrane was used as strategy for entrapment of glucose oxidase and catalase. The biocatalytic productivity of the membrane reactor was found to be highly related to the oxygen availability, which in turn depended on the reactor...

Alginate as immobilization matrix and stabilizing agent in a two-phase liquid system: application in lipase-catalysed reactions.

Science.gov (United States)

Hertzberg, S; Kvittingen, L; Anthonsen, T; Skjåk-Braek, G

1992-01-01

Alginate was evaluated as an immobilization matrix for enzyme-catalyzed reactions in organic solvents. In contrast to most hydrogels, calcium alginate was found to be stable in a range of organic solvents and to retain the enzyme inside the gel matrix. In hydrophobic solvents, the alginate gel (greater than 95% water) thus provided a stable, two-phase liquid system. The lipase from Candida cylindracea, after immobilization in alginate beads, catalysed esterification and transesterification in n-hexane under both batch and continuous-flow conditions. The operational stability of the lipase was markedly enhanced by alginate entrapment. In the esterification of butanoic acid with n-butanol, better results were obtained in the typical hydrophilic calcium alginate beads than in less hydrophilic matrices. The effects of substrate concentration, matrix area, and polarity of the substrate alcohols and of the organic solvent on the esterification activity were examined. The transesterification of octyl 2-bromopropanoate with ethanol was less efficient than that of ethyl 2-bromopropanoate with octanol. By using the hydrophilic alginate gel as an immobilization matrix in combination with a mobile hydrophobic phase, a two-phase liquid system was achieved with definite advantages for a continuous, enzyme-catalysed process.

Immobilized humic substances and immobilized aggregates of humic substances as sorbent for solid phase extraction.

Science.gov (United States)

Erny, Guillaume L; Gonçalves, Bruna M; Esteves, Valdemar I

2013-09-06

In this work, humic substances (HS) immobilized, as a thin layer or as aggregates, on silica gel were tested as material for solid phase extraction. Some triazines (simazine, atrazine, therbutylazine, atrazine-desethyl-desisopropyl-2-hydroxy, ametryn and terbutryn), have been selected as test analytes due to their environmental importance and to span a large range of solubility and octanol/water partition coefficient (logP). The sorbent was obtained immobilizing a thin layer of HS via physisorption on a pre-coated silica gel with a cationic polymer (polybrene). While the sorbent could be used as it is, it was demonstrated that additional HS could be immobilized, via weak interactions, to form stable humic aggregates. However, while a higher quantity of HS could be immobilized, no significant differences were observed in the sorption parameters. This sorbent have been tested for solid phase extraction to concentrate triazines from aqueous matrixes. The sorbent demonstrated performances equivalent to commercial alternatives as a concentration factor between 50 and 200, depending on the type of triazines, was obtained. Moreover the low cost and the high flow rate of sample through the column allowed using high quantity of sorbent. The analytical procedure was tested with different matrixes including tap water, river water and estuarine water. Copyright © 2013 Elsevier B.V. All rights reserved.

Immobilization of cellulase by radiation polymerization

International Nuclear Information System (INIS)

Kumakura, M.; Kaetsu, I.

1983-01-01

Immobilization of cellulase by radiation polymerization at low temperatures was studied. The enzymatic activity of immobilized cellulase pellets varied with the monomer, enzyme concentration, and the thickness of immobilized cellulase pellets. The optimum monomer concentration in the immobilization of cellulase was 30-50% at the pellet thickness of 1.0 mm, in which the enzymatic activity was 50%. The enzymatic activity of immobilized cellulase pellets was examined using various substrates such as cellobiose, carboxymethylcellulose, and paper pretreated by radiation. It was found that irradiated paper can be hydrolyzed by immobilized cellulase pellets. (author)

Immobilized waste leaching

International Nuclear Information System (INIS)

Suarez, A.A.

1989-01-01

The main mechanism by which the immobilized radioactive materials can return to biosphere is the leaching due to the intrusion of water into the repositories. Some mathematical models and experiments utilized to evaluate the leaching rates in different immobilization matrices are described. (author) [pt

Plutonium Disposition by Immobilization

International Nuclear Information System (INIS)

Gould, T.; DiSabatino, A.; Mitchell, M.

2000-01-01

The ultimate goal of the Department of Energy (DOE) Immobilization Project is to develop, construct, and operate facilities that will immobilize between 17 to 50 tonnes (MT) of U.S. surplus weapons-usable plutonium materials in waste forms that meet the ''spent fuel'' standard and are acceptable for disposal in a geologic repository. Using the ceramic can-in-canister technology selected for immobilization, surplus plutonium materials will be chemically combined into ceramic forms which will be encapsulated within large canisters of high level waste (HLW) glass. Deployment of the immobilization capability should occur by 2008 and be completed within 10 years. In support of this goal, the DOE Office of Fissile Materials Disposition (MD) is conducting development and testing (D and T) activities at four DOE laboratories under the technical leadership of Lawrence Livermore National Laboratory (LLNL). The Savannah River Site has been selected as the site for the planned Plutonium Immobilization Plant (PIP). The D and T effort, now in its third year, will establish the technical bases for the design, construction, and operation of the U. S. capability to immobilize surplus plutonium in a suitable and cost-effective manner. Based on the D and T effort and on the development of a conceptual design of the PIP, automation is expected to play a key role in the design and operation of the Immobilization Plant. Automation and remote handling are needed to achieve required dose reduction and to enhance operational efficiency

Nano-Immobilized Biocatalysts for Biodiesel Production from Renewable and Sustainable Resources

Directory of Open Access Journals (Sweden)

Keon Hee Kim

2018-02-01

Full Text Available The cost of biodiesel production relies on feedstock cost. Edible oil is unfavorable as a biodiesel feedstock because of its expensive price. Thus, non-edible crop oil, waste oil, and microalgae oil have been considered as alternative resources. Non-edible crop oil and waste cooking oil are more suitable for enzymatic transesterification because they include a large amount of free fatty acids. Recently, enzymes have been integrated with nanomaterials as immobilization carriers. Nanomaterials can increase biocatalytic efficiency. The development of a nano-immobilized enzyme is one of the key factors for cost-effective biodiesel production. This paper presents the technology development of nanomaterials, including nanoparticles (magnetic and non-magnetic, carbon nanotubes, and nanofibers, and their application to the nano-immobilization of biocatalysts. The current status of biodiesel production using a variety of nano-immobilized lipase is also discussed.

Adaptation of vacuum-assisted mouthpiece head immobilization system for precision infant brain radiation therapy.

Science.gov (United States)

Wong, Kenneth; Cheng, Justine; Bowlin, Kristine; Olch, Arthur

Our purpose was to describe an adaptation of a commercially available mouthpiece for vacuum-assisted mouthpiece immobilization for radiation therapy in infants. An infant diagnosed with a brain tumor required radiation therapy. After reviewing dental literature about obturators, we designed a modification for the smallest commercially available mouthpiece tray. The patient was simulated with the adapted mouthpiece tray. We achieved excellent immobilization and had small daily image guided treatment position shifts. Our patient tolerated treatment well without injury to oral cavity or mucosa. Head immobilization with a vacuum-assisted modified mouthpiece has not been described in infants. Our modification is a novel and safe and permits effective and accurate immobilization for infants for radiation therapy. New manufacturing technologies may allow creation of individualized mouthpieces. Copyright © 2016 American Society for Radiation Oncology. Published by Elsevier Inc. All rights reserved.

Safe immobilization of high-level nuclear reactor wastes

International Nuclear Information System (INIS)

Ringwood, A.; Kesson, S.; Ware, N.; Hibberson, W.; Major, A.

1979-01-01

The advantages and disadvantages of methods of immobilizing high-level radioactive wastes are discussed. Problems include the devitrification of glasses and the occurrence of radiation damage. An alternative method of radioctive waste immobilization is described in which the waste is incorporated in the constituent minerals of a synthetic rock, Synroc. Synroc is immune from devitrification and is composed of phases which possess crystal structures identical to those of minerals which are known to have retained radioactive elements in geological environments at elevated pressures and tempertures for long periods. The composition and mineralogy of Synroc is given and the process of immobilizing wastes in Synroc is described. Accelerated leaching tests at elevated pressures and temperatures are also described

Continuous throughput and long-term observation of single-molecule FRET without immobilization.

Science.gov (United States)

Tyagi, Swati; VanDelinder, Virginia; Banterle, Niccolò; Fuertes, Gustavo; Milles, Sigrid; Agez, Morgane; Lemke, Edward A

2014-03-01

We present an automated microfluidic platform that performs multisecond observation of single molecules with millisecond time resolution while bypassing the need for immobilization procedures. With this system, we confine biomolecules to a thin excitation field by reversibly collapsing microchannels to nanochannels. We demonstrate the power of our method by studying a variety of complex nucleic acid and protein systems, including DNA Holliday junctions, nucleosomes and human transglutaminase 2.

Investigating the dynamics of surface-immobilized DNA nanomachines

Science.gov (United States)

Dunn, Katherine E.; Trefzer, Martin A.; Johnson, Steven; Tyrrell, Andy M.

2016-07-01

Surface-immobilization of molecules can have a profound influence on their structure, function and dynamics. Toehold-mediated strand displacement is often used in solution to drive synthetic nanomachines made from DNA, but the effects of surface-immobilization on the mechanism and kinetics of this reaction have not yet been fully elucidated. Here we show that the kinetics of strand displacement in surface-immobilized nanomachines are significantly different to those of the solution phase reaction, and we attribute this to the effects of intermolecular interactions within the DNA layer. We demonstrate that the dynamics of strand displacement can be manipulated by changing strand length, concentration and G/C content. By inserting mismatched bases it is also possible to tune the rates of the constituent displacement processes (toehold-binding and branch migration) independently, and information can be encoded in the time-dependence of the overall reaction. Our findings will facilitate the rational design of surface-immobilized dynamic DNA nanomachines, including computing devices and track-based motors.

Membranes suited for immobilizing biomolecules

NARCIS (Netherlands)

2009-01-01

The present invention relates to flow-through membranes suitable for the immobilization of biomols., methods for the prepn. of such membranes and the use of such membranes for the immobilization of biomols. and subsequent detection of immobilized biomols. The invention concerns a flow-through

Immobilization of NTPDase-1 from Trypanosoma cruzi and Development of an Online Label-Free Assay.

Science.gov (United States)

Calil, Felipe Antunes; Lima, Juliana Maria; de Oliveira, Arthur Henrique Cavalcante; Mariotini-Moura, Christiane; Fietto, Juliana Lopes Rangel; Cardoso, Carmen Lucia

2016-01-01

The use of IMERs (Immobilized Enzyme Reactors) as a stationary phase coupled to high performance chromatographic systems is an interesting approach in the screening of new ligands. In addition, IMERs offer many advantages over techniques that employ enzymes in solution. The enzyme nucleoside triphosphate diphosphohydrolase (NTPDase-1) from Trypanosoma cruzi acts as a pathogen infection facilitator, so it is a good target in the search for inhibitors. In this paper, immobilization of NTPDase-1 afforded ICERs (Immobilized Capillary Enzyme Reactors). A liquid chromatography method was developed and validated to monitor the ICER activity. The conditions for the application of these bioreactors were investigated, and excellent results were obtained. The enzyme was successfully immobilized, as attested by the catalytic activity detected in the Tc NTPDase-1-ICER chromatographic system. Kinetic studies on the substrate ATP gave K M of 0.317 ± 0.044 mmol·L -1 , which still presented high affinity compared to in solution. Besides that, the ICER was stable for 32 days, enough time to investigate samples of possible inhibitors, including especially the compound Suramin, that inhibited 51% the enzyme activity at 100  µ mol·L -1 , which is in accordance with the data for the enzyme in solution.

Immobilization of NTPDase-1 from Trypanosoma cruzi and Development of an Online Label-Free Assay

Directory of Open Access Journals (Sweden)

Felipe Antunes Calil

2016-01-01

Full Text Available The use of IMERs (Immobilized Enzyme Reactors as a stationary phase coupled to high performance chromatographic systems is an interesting approach in the screening of new ligands. In addition, IMERs offer many advantages over techniques that employ enzymes in solution. The enzyme nucleoside triphosphate diphosphohydrolase (NTPDase-1 from Trypanosoma cruzi acts as a pathogen infection facilitator, so it is a good target in the search for inhibitors. In this paper, immobilization of NTPDase-1 afforded ICERs (Immobilized Capillary Enzyme Reactors. A liquid chromatography method was developed and validated to monitor the ICER activity. The conditions for the application of these bioreactors were investigated, and excellent results were obtained. The enzyme was successfully immobilized, as attested by the catalytic activity detected in the TcNTPDase-1-ICER chromatographic system. Kinetic studies on the substrate ATP gave KM of 0.317 ± 0.044 mmol·L−1, which still presented high affinity compared to in solution. Besides that, the ICER was stable for 32 days, enough time to investigate samples of possible inhibitors, including especially the compound Suramin, that inhibited 51% the enzyme activity at 100 µmol·L−1, which is in accordance with the data for the enzyme in solution.

Wireless Hydrogen Smart Sensor Based on Pt/Graphene-Immobilized Radio-Frequency Identification Tag.

Science.gov (United States)

Lee, Jun Seop; Oh, Jungkyun; Jun, Jaemoon; Jang, Jyongsik

2015-08-25

Hydrogen, a clean-burning fuel, is of key importance to various industrial applications, including fuel cells and the aerospace and automotive industries. However, hydrogen gas is odorless, colorless, and highly flammable; thus, appropriate safety protocol implementation and monitoring are essential. Highly sensitive hydrogen-gas leak detection and surveillance systems are needed; additionally, the ability to monitor large areas (e.g., cities) via wireless networks is becoming increasingly important. In this report, we introduce a radio frequency identification (RFID)-based wireless smart-sensor system, composed of a Pt-decorated reduced graphene oxide (Pt_rGO)-immobilized RFID sensor tag and an RFID-reader antenna-connected network analyzer to detect hydrogen gas. The Pt_rGOs, produced using a simple chemical reduction process, were immobilized on an antenna pattern in the sensor tag through spin coating. The resulting Pt_rGO-based RFID sensor tag exhibited a high sensitivity to hydrogen gas at unprecedentedly low concentrations (1 ppm), with wireless communication between the sensor tag and RFID-reader antenna. The wireless sensor tag demonstrated flexibility and a long lifetime due to the strong immobilization of Pt_rGOs on the substrate and battery-independent operation during hydrogen sensing, respectively.

Immobilization of oxidases and their analytical applications

International Nuclear Information System (INIS)

Yasinzai, M.

2007-01-01

Immobilized enzymes are replacing their soluble counter-parts in nearly every field of application. These enzyme modifications have evolved from a research curiosity into an entire branch of Biotechnology. An immobilization method for flavin containing oxidases and their use in flow injection system is described. An electrochemical detector for H/sub 2/O/sub 2/ is assembled which is used effectively for the determination of glucose using more common glucose oxidase and the simultaneous determination of sugars. The combination of oxidases with hydrolases have been used for the determination of maltose and starch. (author)

Analysis of alternatives for immobilized low activity waste disposal

Energy Technology Data Exchange (ETDEWEB)

Burbank, D.A.

1997-10-28

This report presents a study of alternative disposal system architectures and implementation strategies to provide onsite near-surface disposal capacity to receive the immobilized low-activity waste produced by the private vendors. The analysis shows that a flexible unit strategy that provides a suite of design solutions tailored to the characteristics of the immobilized low-activity waste will provide a disposal system that best meets the program goals of reducing the environmental, health, and safety impacts; meeting the schedule milestones; and minimizing the life-cycle cost of the program.

Analysis of alternatives for immobilized low-activity waste disposal

International Nuclear Information System (INIS)

Burbank, D.A.

1997-01-01

This report presents a study of alternative disposal system architectures and implementation strategies to provide onsite near-surface disposal capacity to receive the immobilized low-activity waste produced by the private vendors. The analysis shows that a flexible unit strategy that provides a suite of design solutions tailored to the characteristics of the immobilized low-activity waste will provide a disposal system that best meets the program goals of reducing the environmental, health, and safety impacts; meeting the schedule milestones; and minimizing the life-cycle cost of the program

New TiO2/DSAT Immobilization System for Photodegradation of Anionic and Cationic Dyes

Directory of Open Access Journals (Sweden)

Wan Izhan Nawawi Wan Ismail

2015-01-01

Full Text Available A new immobilized TiO2 technique was prepared by coating TiO2 solution onto double-sided adhesive tape (DSAT as a thin layer binder without adding any organic additives. Glass plate was used as support material to immobilized TiO2/DSAT. Two different charges of dyes were applied, namely, anionic reactive red 4 (RR4 and cationic methylene blue (MB dyes. Photocatalytic degradation of RR4 and MB dyes was observed under immobilized TiO2/DSAT with the degradation rate slightly lower and higher, respectively, compared with TiO2 in suspension mode. It was observed that DSAT is able to provide a very strong intact between glass and TiO2 layers thus making the reusability of immobilized TiO2/DSAT be up to 30 cycles. In fact, a better photodegradation activity was observed by number of cycles due to increasing formation of pores on TiO2 surface observed by SEM analysis.

Microorganism immobilization

Science.gov (United States)

Compere, Alicia L.; Griffith, William L.

1981-01-01

Live metabolically active microorganisms are immobilized on a solid support by contacting particles of aggregate material with a water dispersible polyelectrolyte such as gelatin, crosslinking the polyelectrolyte by reacting it with a crosslinking agent such as glutaraldehyde to provide a crosslinked coating on the particles of aggregate material, contacting the coated particles with live microorganisms and incubating the microorganisms in contact with the crosslinked coating to provide a coating of metabolically active microorganisms. The immobilized microorganisms have continued growth and reproduction functions.

Plasma lactate concentrations in free-ranging moose (Alces alces) immobilized with etorphine.

Science.gov (United States)

Haga, Henning A; Wenger, Sandra; Hvarnes, Silje; Os, Oystein; Rolandsen, Christer M; Solberg, Erling J

2009-11-01

To investigate plasma lactate concentrations of etorphine-immobilized moose in relation to environmental, temporal and physiological parameters. Prospective clinical study. Fourteen female and five male moose (Alces alces), estimated age range 1-7 years. The moose were darted from a helicopter with 7.5 mg etorphine per animal using projectile syringes and a dart gun. Once immobilized, the moose were approached, a venous blood sample was obtained and vital signs including pulse oximetry were recorded. Diprenorphine was administered to reverse the effects of etorphine. Timing of events, ambient temperature and snow depth were recorded. Blood samples were cooled and centrifuged before plasma was harvested and frozen. The plasma was thawed later and lactate analysed. Data were analysed using descriptive statistics and regression analysis. All animals recovered uneventfully and were alive 12 weeks after immobilization. Mean +/- SD plasma lactate was found to be 9.2 +/- 2.1 mmol L(-1). Plasma lactate concentrations were related positively to snow depth and negatively to time from induction of immobilization to blood sampling. The model that best described the variability in plasma lactate concentrations used induction time (time from firing the dart to the moose being immobilized). The second best model included induction time and snow depth. Plasma lactate concentrations in these etorphine-immobilized moose were in the range reported for other immobilized wild ruminants. Decreasing induction time, which may be related to a more profound etorphine effect, and increasing snow depth possibly may increase plasma lactate concentrations in etorphine-immobilized moose.

Immobilization of wet solid wastes at nuclear power plants

International Nuclear Information System (INIS)

Neilson, R.M. Jr.

1977-01-01

Wet solid wastes are classified into four basic types: spent resins, filter sludges, evaporator concentrates, and miscellaneous liquids. Although the immobilization of wet solid wastes is primarily concerned with the incorporation of the waste with a solidification agent, there are a number of other discrete operations or subsystems involved in the treatment of these wastes that may affect the immobilized waste product. The immobilization process may be broken down into five basic operations: waste collection, waste pretreatment, solidification agent handling, mixing/packaging, and waste package handling. The properties of the waste forms that are ultimately shipped from the reactor site are primarily influenced by the methods utilized during the waste collection, waste pretreatment and mixing/packaging operations. The mixing/packaging (solidification) operation is perhaps the most important stage of the immobilization process. The basic solidification agent types are: absorbants, hydraulic cement, urea-formaldehyde, bitumen, and other polymer systems

Immobilization of organic liquid wastes

International Nuclear Information System (INIS)

Greenhalgh, W.O.

1985-01-01

This report describes a portland cement immobilization process for the disposal treatment of radioactive organic liquid wastes which would be generated in a a FFTF fuels reprocessing line. An incineration system already on-hand was determined to be too costly to operate for the 100 to 400 gallons per year organic liquid. Organic test liquids were dispersed into an aqueous phosphate liquid using an emulsifier. A total of 109 gallons of potential and radioactive aqueous immiscible organic liquid wastes from Hanford 300 Area operations were solidified with portland cement and disposed of as solid waste during a 3-month test program with in-drum mixers. Waste packing efficiencies varied from 32 to 40% and included pump oils, mineral spirits, and TBP-NPH type solvents

SU-F-T-640: Feasibility of Using a Commercially Available Surface Guided Radiotherapy System with An Open-Face SRS Immobilization System

Energy Technology Data Exchange (ETDEWEB)

Chinsky, B; Patel, R; Roeske, J; Surucu, M [Loyola University Medical Center, Maywood, IL (United States)

2016-06-15

Purpose: To evaluate the inherent accuracy of using a surface guided radiotherapy system (SGRT) in the setup and monitoring of patients receiving stereotactic radiosurgery with an open-face SRS immobilization system. Methods: An anthropomorphic head phantom was set up using the Qfix Encompass SRS Immobilization System on a Varian Edge with OSMS and Varian TrueBeam with AlignRT. The phantom was positioned at 0° gantry and couch. A reference image was acquired using the SGRT system and an ROI was created over the mask opening. The couch and gantry were rotated to different combinations focusing on clinically used SRS gantry/couch combinations and those blocking the SGRT cameras. Perceived surface deviation by the SGRT system from the reference image was recorded. A Winston-Lutz test was performed on couch angles tested and used to exclude couch walkout. The deviation magnitude was calculated using translational values and rotational raw values were recorded. Results: The maximum couch walkouts were: 0.4mm (Edge) and 0.5mm (TB). Solely rotating the gantry resulted in a median couch deviation of 0.2mm and range of 0.1–0.3mm for both linacs. Only rotating the couch (0° gantry) resulted in median deviations of 0.6mm and 0.5mm with ranges of 0.3–1.0mm and 0.3–0.7mm for the Edge and TB, respectively. Combining gantry and couch rotations, the median deviations were 0.7mm and 0.9mm with ranges of 0.3–1.1mm and 0.2–1.9mm for the Edge and TB, respectively. Including all combinations, rotation, roll, and pitch median deviations ranged from 0.1–0.3° with pitch demonstrating consistently higher values and a maximum deviation of 1.0° (both linacs). Conclusion: SGRT is a reliable monitoring tool, though taking into account system fluctuations, 1mm is too restrictive a site tolerance to use with the Qfix Encompass mask. Gantry rotation has little effect on system fluctuation even with camera blockage, whereas couch rotation has a larger effect.

SU-F-T-640: Feasibility of Using a Commercially Available Surface Guided Radiotherapy System with An Open-Face SRS Immobilization System

International Nuclear Information System (INIS)

Chinsky, B; Patel, R; Roeske, J; Surucu, M

2016-01-01

Purpose: To evaluate the inherent accuracy of using a surface guided radiotherapy system (SGRT) in the setup and monitoring of patients receiving stereotactic radiosurgery with an open-face SRS immobilization system. Methods: An anthropomorphic head phantom was set up using the Qfix Encompass SRS Immobilization System on a Varian Edge with OSMS and Varian TrueBeam with AlignRT. The phantom was positioned at 0° gantry and couch. A reference image was acquired using the SGRT system and an ROI was created over the mask opening. The couch and gantry were rotated to different combinations focusing on clinically used SRS gantry/couch combinations and those blocking the SGRT cameras. Perceived surface deviation by the SGRT system from the reference image was recorded. A Winston-Lutz test was performed on couch angles tested and used to exclude couch walkout. The deviation magnitude was calculated using translational values and rotational raw values were recorded. Results: The maximum couch walkouts were: 0.4mm (Edge) and 0.5mm (TB). Solely rotating the gantry resulted in a median couch deviation of 0.2mm and range of 0.1–0.3mm for both linacs. Only rotating the couch (0° gantry) resulted in median deviations of 0.6mm and 0.5mm with ranges of 0.3–1.0mm and 0.3–0.7mm for the Edge and TB, respectively. Combining gantry and couch rotations, the median deviations were 0.7mm and 0.9mm with ranges of 0.3–1.1mm and 0.2–1.9mm for the Edge and TB, respectively. Including all combinations, rotation, roll, and pitch median deviations ranged from 0.1–0.3° with pitch demonstrating consistently higher values and a maximum deviation of 1.0° (both linacs). Conclusion: SGRT is a reliable monitoring tool, though taking into account system fluctuations, 1mm is too restrictive a site tolerance to use with the Qfix Encompass mask. Gantry rotation has little effect on system fluctuation even with camera blockage, whereas couch rotation has a larger effect.

Immobilization of hazardous and radioactive waste into glass structures

International Nuclear Information System (INIS)

Wicks, G.G.

1997-01-01

As a result of more than three decades of international research, glass has emerged as the material of choice for immobilization of a wide range of potentially hazardous radioactive and non-radioactive materials. The ability of glass structures to incorporate and then immobilize many different elements into durable, high integrity, waste glass products is a direct function of the unique random network structure of the glassy state. Every major country involved with long-term management of high-level radioactive waste (HLW) has either selected or is considering glass as the matrix of choice for immobilizing and ultimately, disposing of the potentially hazardous, high-level radioactive material. There are many reasons why glass is preferred. Among the most important considerations are the ability of glass structures to accommodate and immobilize the many different types of radionuclides present in HLW, and to produce a product that not only has excellent technical properties, but also possesses good processing features. Good processability allows the glass to be fabricated with relative ease even under difficult remote-handling conditions necessary for vitrification of highly radioactive material. The single most important property of the waste glass produced is its ability to retain hazardous species within the glass structure and this is reflected by its excellent chemical durability and corrosion resistance to a wide range of environmental conditions. In addition to immobilization of HLW glass matrices are also being considered for isolation of many other types of hazardous materials, both radioactive as well as nonradioactive. This includes vitrification of various actinides resulting from clean-up operations and the legacy of the cold war, as well as possible immobilization of weapons grade plutonium resulting from disarmament activities. Other types of wastes being considered for immobilization into glasses include transuranic wastes, mixed wastes, contaminated

Nanoclays for Lipase Immobilization: Biocatalyst Characterization and Activity in Polyester Synthesis

Directory of Open Access Journals (Sweden)

Hale Öztürk

2016-12-01

Full Text Available The immobilization of Candida antarctica lipase B (CALB was performed by physical adsorption on both neat and organo-modified forms of sepiolite and montmorillonite. The influence of different parameters, e.g., solvent, enzyme loading, cross-linking, and type of clay support, on immobilization efficiency and catalyst hydrolytic activity has been investigated. The highest hydrolytic activities were obtained for CALB immobilized on organo-modified clay minerals, highlighting the beneficial effect of organo-modification. The esterification activity of these CALB/organoclay catalysts was also tested in the ring-opening polymerization of ε-caprolactone. The polymerization kinetics observed for clay-immobilized catalysts confirmed that CALB adsorbed on organo-modified montmorillonite (CALB/MMTMOD was the highest-performing catalytic system.

Supplemental Immobilization Cast Stone Technology Development and Waste Form Qualification Testing Plan

Energy Technology Data Exchange (ETDEWEB)

Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Serne, R. Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Pierce, Eric M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cozzi, Alex [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Chung, Chul-Woo [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Swanberg, David J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2013-05-31

The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the 56 million gallons of radioactive waste stored in 177 underground tanks at the Hanford Site. The WTP includes a pretreatment facility to separate the wastes into high-level waste (HLW) and low-activity waste (LAW) fractions for vitrification and disposal. The LAW will be converted to glass for final disposal at the Integrated Disposal Facility (IDF). The pretreatment facility will have the capacity to separate all of the tank wastes into the HLW and LAW fractions, and the HLW Vitrification Facility will have the capacity to vitrify all of the HLW. However, a second immobilization facility will be needed for the expected volume of LAW requiring immobilization. A number of alternatives, including Cast Stone—a cementitious waste form—are being considered to provide the additional LAW immobilization capacity.

An orientation analysis method for protein immobilized on quantum dot particles

Energy Technology Data Exchange (ETDEWEB)

Aoyagi, Satoka, E-mail: aoyagi@life.shimane-u.ac.jp [Faculty of Life and Environmental Science, Shimane University, 1060 Matsue-shi, Shimane 690-8504 (Japan); Inoue, Masae [Toyota Central R and D Labs., Inc., Nagakute, Aichi 480-1192 (Japan)

2009-11-30

The evaluation of orientation of biomolecules immobilized on nanodevices is crucial for the development of high performance devices. Such analysis requires ultra high sensitivity so as to be able to detect less than one molecular layer on a device. Time-of-flight secondary ion mass spectrometry (TOF-SIMS) has sufficient sensitivity to evaluate the uppermost surface structure of a single molecular layer. The objective of this study is to develop an orientation analysis method for proteins immobilized on nanomaterials such as quantum dot particles, and to evaluate the orientation of streptavidin immobilized on quantum dot particles by means of TOF-SIMS. In order to detect fragment ions specific to the protein surface, a monoatomic primary ion source (Ga{sup +}) and a cluster ion source (Au{sub 3}{sup +}) were employed. Streptavidin-immobilized quantum dot particles were immobilized on aminosilanized ITO glass plates at amino groups by covalent bonding. The reference samples streptavidin directly immobilized on ITO plates were also prepared. All samples were dried with a freeze dryer before TOF-SIMS measurement. The positive secondary ion spectra of each sample were obtained using TOF-SIMS with Ga{sup +} and Au{sub 3}{sup +}, respectively, and then they were compared so as to characterize each sample and detect the surface structure of the streptavidin immobilized with the biotin-immobilized quantum dots. The chemical structures of the upper surface of the streptavidin molecules immobilized on the quantum dot particles were evaluated with TOF-SIMS spectra analysis. The indicated surface side of the streptavidin molecules immobilized on the quantum dots includes the biotin binding site.

Simultaneously and separately immobilizing incompatible dual-enzymes on polymer substrate via visible light induced graft polymerization

Science.gov (United States)

Zhu, Xing; He, Bin; Zhao, Changwen; Ma, Yuhong; Yang, Wantai

2018-04-01

Developing facile and mild strategy to construct multi-enzymes immobilization system has attracted considerable attentions in recent years. Here a simple immobilization strategy called visible light induced graft polymerization that can simultaneously and separately encapsulate two kinds of enzymes on one polymer film was proposed. Two incompatible enzymes, trypsin and transglutaminase (TGase) were selected as model dual-enzymes system and simultaneously immobilized on two sides of low-density polyethylene (LDPE) film. After immobilization, it was found that more than 90% of the enzymes can be embedded into dual-enzymes loaded film without leakage. And the activities of both separately immobilized enzymes were higher than the activities of mixed co-immobilized enzymes or the sequential immobilized ones. This dual-enzymes loaded film (DEL film) showed excellent recyclability and can retain >87% activities of both enzymes after 4 cycles of utilization. As an example, this DEL film was used to conjugate a prodrug of cytarabine with a target peptide. The successful preparation of expected product demonstrated that the separately immobilized two enzymes can worked well together to catalyze a two-step reaction.

Utility Estimation of the Manufactured Stereotactic Body Radiotherapy Immobilization

International Nuclear Information System (INIS)

Lee, Dong Hoon; Ahn, Jong Ho; Seo, Jeong Min; Shin, Eun Hyeak; Choi, Byeong Gi; Song, Gi Won

2011-01-01

Immobilizations used in order to maintain the reproducibility of a patient set-up and the stable posture for a long period are important more than anything else for the accurate treatment when the stereotactic body radiotherapy is underway. So the purpose of this study is to adapt the optimum immobilizations for the stereotactic body radiotherapy by comparing two commercial immobilizations with the self-manufactured immobilizations. Five people were selected for the experiment and three different immobilizations (A: Wing-board, B: BodyFix system, C: Arm up holder with vac-lock) were used to each target. After deciding on the target's most stable respiratory cycles, the targets were asked to wear a goggle monitor and maintain their respiration regularly for thirty minutes to obtain the respiratory signals. To analyze the respiratory signal, the standard deviation and the variation value of the peak value and the valley value of the respiratory signal were separated by time zone with the self-developed program at the hospital and each tie-downs were compared for the estimation by calculating a comparative index using the above. The stability of each immobilizations were measured in consideration of deviation changes studied in each respiratory time lapse. Comparative indexes of each immobilizations of each experimenter are shown to be A: 11.20, B: 4.87, C: 1.63 / A: 3.94, B: 0.67, C: 0.13 / A: 2.41, B: 0.29, C: 0.04 / A: 0.16, B: 0.19, C: 0.007 / A: 35.70, B: 2.37, C: 1.86. And when all five experimenters wore the immobilizations C, the test proved the most stable value while four people wearing A and one man wearing D expressed relatively the most unstable respiratory outcomes. The self-developed immobilizations, so called the arm up holder vac-lock for the stereotactic body radiotherapy is expected to improve the effect of the treatment by decreasing the intra-fraction organ motions because it keeps the respiration more stable than other two immobilizations

Immobilization of leachable toxic soil pollutants by using oxidative enzymes

International Nuclear Information System (INIS)

Shannon, M.J.R.; Bartha, R.

1988-01-01

Screening of leachable toxic chemicals in a horseradish peroxidase-H 2 O 2 immobilization system established that immobilization was promising for most phenolic pollutants but not for benzoic acid, 2,6-dinitrocresol, or dibutyl phthalate. The treatment did not mobilize inherently nonmobile pollutants such as anilines and benzo[a]pyrene. In a separate study, an extracellular laccase in the culture filtrate of Geotrichum candidum was selected from five fungal enzymes evaluated as a cost-effective substitute for horseradish peroxidase. This enzyme was used in demonstrating the immobilization and subsequent fate of 14 C-labeled 4-methylphenol and 2,4-dichlorophenol in soil columns. When applied to Lakewood sand, 98.1% of 4-methylpheno was leached through with distilled water. Two days after immobilization treatment with the G. candidum culture filtrate, only 9.1% of the added 4-methylphenol was leached with the same volume of water. Of the more refractory test pollutant 2,4-dichlorophenol, 91.6% had leached at time zero and 48.5% had leached 1 day after the immobilization treatment. However, 2 weeks after immobilization, only 12.0% of the 2,4-dichlorophenol was leached compared with 61.7% from the control column that received no immobilization treatment. No remobilization of the bound pollutants was detected during 3- and 4-week incubation periods

Immobilized enzymes in blood plasma exchangers via radiation grafting

Science.gov (United States)

Gombotz, Wayne; Hoffman, Allan; Schmer, Gottfried; Uenoyama, Satoshi

The enzyme asparaginase was immobilized onto a porous hollow polypropylene (PP) fiber blood plasma exchange device for the treatment of acute lymphocytic leukemia. The devices were first radiation grafted with polymethacrylic acid (poly(MAAc)). This introduces carboxyl groups onto the surface of the fibers. Several variables were studied in the grafting reaction including the effects of solvent type and monomer concentration. The carboxyl groups were activated with N-hydroxy succinimide (NHS) using carbodiimide chemistry. Asparaginase was then covalently immobilized on the activated surfaces. Quantitative relationships were found relating the percent graft to the amount of immobilized enzyme which was active. The enzyme reactor was tested both in vitro and in vivo using a sheep as an animal model.

Supramolecular protein immobilization on lipid bilayers

NARCIS (Netherlands)

Bosmans, R.P.G.; Hendriksen, W.E.; Verheijden, Mark Lloyd; Eelkema, R.; Jonkheijm, Pascal; van Esch, J.H.; Brunsveld, Luc

2015-01-01

Protein immobilization on surfaces, and on lipid bilayers specifically, has great potential in biomolecular and biotechnological research. Of current special interest is the immobilization of proteins using supramolecular noncovalent interactions. This allows for a reversible immobilization and

The enhancement of chondrogenesis of ATDC5 cells in RGD-immobilized microcavitary alginate hydrogels.

Science.gov (United States)

Yao, Yongchang; Zeng, Lei; Huang, Yuyang

2016-07-01

In our previous work, we have developed an effective microcavitary alginate hydrogel for proliferation of chondrocytes and maintenance of chondrocytic phenotype. In present work, we investigated whether microcavitary alginate hydrogel could promote the chondrogenesis of progenitor cells. Moreover, we attempted to further optimize this system by incorporating synthetic Arg-Gly-Asp peptide. ATDC5 cells were seeded into microcavitary alginate hydrogel with or without Arg-Gly-Asp immobilization. Cell Counting Kit-8 and live/dead staining were conducted to analyze cell proliferation. Real-time polymerase chain reaction (RT-PCR), hematoxylin and eosin, and Toluidine blue O staining as well as Western blot assay was performed to evaluate the cartilaginous markers at transcriptional level and at protein level, respectively. The obtained data demonstrated that Arg-Gly-Asp-immobilized microcavitary alginate hydrogel was preferable to promote the cell proliferation. Also, Arg-Gly-Asp-immobilized microcavitary alginate hydrogel improved the expression of chondrocytic genes including Collagen II and Aggrecan when compared with microcavitary alginate hydrogel. The results suggested that microcavitary alginate hydrogel could promote the chondrogenesis. And Arg-Gly-Asp would be promising to ameliorate this culture system for cartilage tissue engineering. © The Author(s) 2016.

Bioconversion of Airborne Methylamine by Immobilized Recombinant Amine Oxidase from the Thermotolerant Yeast Hansenula polymorpha

Directory of Open Access Journals (Sweden)

Sasi Sigawi

2014-01-01

Full Text Available Aliphatic amines, including methylamine, are air-pollutants, due to their intensive use in industry and the natural degradation of proteins, amino acids, and other nitrogen-containing compounds in biological samples. It is necessary to develop systems for removal of methylamine from the air, since airborne methylamine has a negative effect on human health. The primary amine oxidase (primary amine : oxygen oxidoreductase (deaminating or amine oxidase, AMO; EC 1.4.3.21, a copper-containing enzyme from the thermotolerant yeast Hansenula polymorpha which was overexpressed in baker’s yeast Saccharomyces cerevisiae, was tested for its ability to oxidize airborne methylamine. A continuous fluidized bed bioreactor (CFBR was designed to enable bioconversion of airborne methylamine by AMO immobilized in calcium alginate (CA beads. The results demonstrated that the bioreactor with immobilized AMO eliminates nearly 97% of the airborne methylamine. However, the enzymatic activity of AMO causes formation of formaldehyde. A two-step bioconversion process was therefore proposed. In the first step, airborne methylamine was fed into a CFBR which contained immobilized AMO. In the second step, the gas flow was passed through another CFBR, with alcohol oxidase from the yeast H. polymorpha immobilized in CA, in order to decompose the formaldehyde formed in the first step. The proposed system provided almost total elimination of the airborne methylamine and the formaldehyde.

Immobilization of enzymes by radiation

International Nuclear Information System (INIS)

Kaetsu, I.; Kumakura, M.; Yoshida, M.; Asano, M.; Himei, M.; Tamura, M.; Hayashi, K.

1979-01-01

Immobilization of various enzymes was performed by radiation-induced polymerization of glass-forming monomers at low temperatures. Alpha-amylase and glucoamylase were effectively immobilized in hydrophilic polymer carrier such as poly(2-hydroxyethyl methacrylate) and also in rather hydrophobic carrier such as poly(tetraethylene-glycol diacrylate). Immobilized human hemoglobin underwent the reversible oxygenation concomitantly with change of oxygen concentration outside of the matrices. (author)

Clinical benefits of new immobilization system for hypofractionated radiotherapy of intrahepatic hepatocellular carcinoma by helical tomotherapy

Energy Technology Data Exchange (ETDEWEB)

Hu, Yong; Zhou, Yong-Kang; Chen, Yi-Xing; Shi, Shi-Ming; Zeng, Zhao-Chong, E-mail: zeng.zhaochong@zs-hospital.sh.cn

2017-04-01

Objective: A comprehensive clinical evaluation was conducted, assessing the Body Pro-Lok immobilization and positioning system to facilitate hypofractionated radiotherapy of intrahepatic hepatocellular carcinoma (HCC), using helical tomotherapy to improve treatment precision. Methods: Clinical applications of the Body Pro-Lok system were investigated (as above) in terms of interfractional and intrafractional setup errors and compressive abdominal breath control. To assess interfractional setup errors, a total of 42 patients who were given 5 to 20 fractions of helical tomotherapy for intrahepatic HCC were analyzed. Overall, 15 patients were immobilized using simple vacuum cushion (group A), and the Body Pro-Lok system was used in 27 patients (group B), performing megavoltage computed tomography (MVCT) scans 196 times and 435 times, respectively. Pretreatment MVCT scans were registered to the planning kilovoltage computed tomography (KVCT) for error determination, and group comparisons were made. To establish intrafractional setup errors, 17 patients with intrahepatic HCC were selected at random for immobilization by Body Pro-Lok system, undergoing MVCT scans after helical tomotherapy every week. A total of 46 MVCT re-scans were analyzed for this purpose. In researching breath control, 12 patients, randomly selected, were immobilized by Body Pro-Lok system and subjected to 2-phase 4-dimensional CT (4DCT) scans, with compressive abdominal control or in freely breathing states, respectively. Respiratory-induced liver motion was then compared. Results: Mean interfractional setup errors were as follows: (1) group A: X, 2.97 ± 2.47 mm; Y, 4.85 ± 4.04 mm; and Z, 3.77 ± 3.21 mm; pitch, 0.66 ± 0.62°; roll, 1.09 ± 1.06°; and yaw, 0.85 ± 0.82°; and (2) group B: X, 2.23 ± 1.79 mm; Y, 4.10 ± 3.36 mm; and Z, 1.67 ± 1.91 mm; pitch, 0.45 ± 0.38°; roll, 0.77 ± 0.63°; and yaw, 0.52 ± 0.49°. Between-group differences were statistically significant in 6 directions (p

Clinical benefits of new immobilization system for hypofractionated radiotherapy of intrahepatic hepatocellular carcinoma by helical tomotherapy

International Nuclear Information System (INIS)

Hu, Yong; Zhou, Yong-Kang; Chen, Yi-Xing; Shi, Shi-Ming; Zeng, Zhao-Chong

2017-01-01

Objective: A comprehensive clinical evaluation was conducted, assessing the Body Pro-Lok immobilization and positioning system to facilitate hypofractionated radiotherapy of intrahepatic hepatocellular carcinoma (HCC), using helical tomotherapy to improve treatment precision. Methods: Clinical applications of the Body Pro-Lok system were investigated (as above) in terms of interfractional and intrafractional setup errors and compressive abdominal breath control. To assess interfractional setup errors, a total of 42 patients who were given 5 to 20 fractions of helical tomotherapy for intrahepatic HCC were analyzed. Overall, 15 patients were immobilized using simple vacuum cushion (group A), and the Body Pro-Lok system was used in 27 patients (group B), performing megavoltage computed tomography (MVCT) scans 196 times and 435 times, respectively. Pretreatment MVCT scans were registered to the planning kilovoltage computed tomography (KVCT) for error determination, and group comparisons were made. To establish intrafractional setup errors, 17 patients with intrahepatic HCC were selected at random for immobilization by Body Pro-Lok system, undergoing MVCT scans after helical tomotherapy every week. A total of 46 MVCT re-scans were analyzed for this purpose. In researching breath control, 12 patients, randomly selected, were immobilized by Body Pro-Lok system and subjected to 2-phase 4-dimensional CT (4DCT) scans, with compressive abdominal control or in freely breathing states, respectively. Respiratory-induced liver motion was then compared. Results: Mean interfractional setup errors were as follows: (1) group A: X, 2.97 ± 2.47 mm; Y, 4.85 ± 4.04 mm; and Z, 3.77 ± 3.21 mm; pitch, 0.66 ± 0.62°; roll, 1.09 ± 1.06°; and yaw, 0.85 ± 0.82°; and (2) group B: X, 2.23 ± 1.79 mm; Y, 4.10 ± 3.36 mm; and Z, 1.67 ± 1.91 mm; pitch, 0.45 ± 0.38°; roll, 0.77 ± 0.63°; and yaw, 0.52 ± 0.49°. Between-group differences were statistically significant in 6 directions (p

Immobilization of anode-attached microbes in a microbial fuel cell.

KAUST Repository

Wagner, Rachel C

2012-01-03

Current-generating (exoelectrogenic) bacteria in bioelectrochemical systems (BESs) may not be culturable using standard in vitro agar-plating techniques, making isolation of new microbes a challenge. More in vivo like conditions are needed where bacteria can be grown and directly isolated on an electrode. While colonies can be developed from single cells on an electrode, the cells must be immobilized after being placed on the surface. Here we present a proof-of-concept immobilization approach that allows exoelectrogenic activity of cells on an electrode based on applying a layer of latex to hold bacteria on surfaces. The effectiveness of this procedure to immobilize particles was first demonstrated using fluorescent microspheres as bacterial analogs. The latex coating was then shown to not substantially affect the exoelectrogenic activity of well-developed anode biofilms in two different systems. A single layer of airbrushed coating did not reduce the voltage produced by a biofilm in a microbial fuel cell (MFC), and more easily applied dip-and-blot coating reduced voltage by only 11% in a microbial electrolysis cell (MEC). This latex immobilization procedure will enable future testing of single cells for exoelectrogenic activity on electrodes in BESs.

Immobilization of anode-attached microbes in a microbial fuel cell.

KAUST Repository

Wagner, Rachel C; Porter-Gill, Sikandar; Logan, Bruce E

2012-01-01

Current-generating (exoelectrogenic) bacteria in bioelectrochemical systems (BESs) may not be culturable using standard in vitro agar-plating techniques, making isolation of new microbes a challenge. More in vivo like conditions are needed where bacteria can be grown and directly isolated on an electrode. While colonies can be developed from single cells on an electrode, the cells must be immobilized after being placed on the surface. Here we present a proof-of-concept immobilization approach that allows exoelectrogenic activity of cells on an electrode based on applying a layer of latex to hold bacteria on surfaces. The effectiveness of this procedure to immobilize particles was first demonstrated using fluorescent microspheres as bacterial analogs. The latex coating was then shown to not substantially affect the exoelectrogenic activity of well-developed anode biofilms in two different systems. A single layer of airbrushed coating did not reduce the voltage produced by a biofilm in a microbial fuel cell (MFC), and more easily applied dip-and-blot coating reduced voltage by only 11% in a microbial electrolysis cell (MEC). This latex immobilization procedure will enable future testing of single cells for exoelectrogenic activity on electrodes in BESs.

Rapid detection of food pathogens using RNA aptamers-immobilized slide.

Science.gov (United States)

Maeng, Jin-Soo; Kim, Namsoo; Kim, Chong-Tai; Han, Seung Ryul; Lee, Young Ju; Lee, Seong-Wook; Lee, Myung-Hyun; Cho, Yong-Jin

2012-07-01

The purpose of this study was to develop a simple and rapid detection system for foodborne bacteria, which consisted of an optical microscope and its slide chip with artificial antibodies, or RNA aptamers. From an RNA pool, three each RNA aptamers were built by the method of SELEX (systematic evolution of ligands by exponential enrichment) for components of cell wall, LPS (lipopolysaccharide) from E. coli O157:H7, teichoic acid from Staphylococcus aureus and a cell membrane protein of OmpC from Salmonella typhimurium, respectively. These aptamers were hybridized with thiol-conjugated 16 dT-linker molecules in order to be immobilized on silver surface which was, in advance, fabricated on glass slide, using a spin-coating method. To confirm that each aptamers retained its specific binding activities to their antigenic live bacteria, microscopic view of bound cells immobilized on silver film were observed. Furthermore, we observed the fluorescence-emitting bacteria-aptamer complex immobilized on silver film after adding RNA aptamers hybridized with fluorophore, FAM-conjugated 16 dT-linker molecules. As a result, the RNA aptamers-immobilized slide system developed in this study was a useful new tool to rapidly monitor individual food pathogens.

Continuous Ethanol Production Using Immobilized-Cell/Enzyme Biocatalysts in Fluidized-Bed Bioreactor (FBR)

Energy Technology Data Exchange (ETDEWEB)

Nghiem, NP

2003-11-16

The immobilized-cell fluidized-bed bioreactor (FBR) was developed at Oak Ridge National Laboratory (ORNL). Previous studies at ORNL using immobilized Zymomonas mobilis in FBR at both laboratory and demonstration scale (4-in-ID by 20-ft-tall) have shown that the system was more than 50 times as productive as industrial benchmarks (batch and fed-batch free cell fermentations for ethanol production from glucose). Economic analysis showed that a continuous process employing the FBR technology to produce ethanol from corn-derived glucose would offer savings of three to six cents per gallon of ethanol compared to a typical batch process. The application of the FBR technology for ethanol production was extended to investigate more complex feedstocks, which included starch and lignocellulosic-derived mixed sugars. Economic analysis and mathematical modeling of the reactor were included in the investigation. This report summarizes the results of these extensive studies.

[Phase transfer catalyzed bioconversion of penicillin G to 6-APA by immobilized penicillin acylase in recyclable aqueous two-phase systems with light/pH sensitive copolymers].

Science.gov (United States)

Jin, Ke-ming; Cao, Xue-jun; Su, Jin; Ma, Li; Zhuang, Ying-ping; Chu, Ju; Zhang, Si-liang

2008-03-01

Immobilized penicillin acylase was used for bioconversion of penicillin PG into 6-APA in aqueous two-phase systems consisting of a light-sensitive polymer PNBC and a pH-sensitive polymer PADB. Partition coefficients of 6-APA was found to be about 5.78 in the presence of 1% NaCl. Enzyme kinetics showed that the reaction reached equilibrium at roughly 7 h. The 6-APA mole yields were 85.3% (pH 7.8, 20 degrees C), with about 20% increment as compared with the reaction of single aqueous phase buffer. The partition coefficient of PG (Na) varied scarcely, while that of the product, 6-APA and phenylacetic acid (PA) significantly varied due to Donnan effect of the phase systems and hydrophobicity of the products. The variation of the partition coefficients of the products also affected the bioconversion yield of the products. In the aqueous two-phase systems, the substrate, PG, the products of 6-APA and PA were biased in the top phase, while immobilized penicillin acylase at completely partitioned at the bottom. The substrate and PG entered the bottom phase, where it was catalyzed into 6-APA and PA and entered the top phase. Inhibition of the substrate and products was removed to result in improvement of the product yield, and the immobilized enzyme showed higher efficiency than the immobilized cells and occupied smaller volume. Compared with the free enzyme, immobilized enzyme had greater stability, longer life-time, and was completely partitioned in the bottom phase and recycle. Bioconversion in two-phase systems using immobilized penicillin acylase showed outstanding advantage. The light-sensitive copolymer forming aqueous two-phase systems could be recovered by laser radiation at 488 nm or filtered 450 nm light, while pH-sensitive polymer PADB could be recovered at the isoelectric point (pH 4.1). The recovery of the two copolymers was between 95% and 99%.

Progress in biocatalysis with immobilized viable whole cells: systems development, reaction engineering and applications

Czech Academy of Sciences Publication Activity Database

Polakovič, M.; Švitel, J.; Bučko, M.; Filip, J.; Neděla, Vilém; Ansorge-Schumacher, M.B.; Gemeiner, P.

2017-01-01

Roč. 39, č. 5 (2017), s. 667-683 ISSN 0141-5492 Institutional support: RVO:68081731 Keywords : biocatalysis * immobilization methods * immobilized whole-cell biocatalyst * multienzyme cascade reactions * process economics * reaction engineering Subject RIV: JA - Electronics ; Optoelectronics, Electrical Engineering OBOR OECD: Bioprocessing technologies (industrial processes relying on biological agents to drive the process) biocatalysis, fermentation Impact factor: 1.730, year: 2016

Stabilization of α-amylase by using anionic surfactant during the immobilization process

Science.gov (United States)

El-Batal, A. I.; Atia, K. S.; Eid, M.

2005-10-01

This work describes the entrapment of α-amylase into butylacrylate-acrylic acid copolymer (BuA/AAc) using γ irradiation. The effect of an anionic surfactant (AOT), the reuse efficiency, and kinetic behavior of immobilized α-amylase were studied. Covering of α-amylase with bis-(2-ethylhexyl)sulfosuccinate sodium salt (AOT) made the enzyme more stable than the uncovered form. The hydrolytic activity of the pre-coated immobilized α-amylase was increased below the critical micelle concentration (cmc) (10 mmol/L). The results showed an increase in the relative activity with increase in the degree of hydration. The pre-coated immobilized α-amylase showed a higher k/K and lower activation energy compared to the free and uncoated-immobilized preparation, respectively. The results suggest that the immobilization of α-amylase is a potentially useful approach for commercial starch hydrolysis in two-phase systems.

Uranium speciation and stability after reductive immobilization in sediments.

OpenAIRE

Sharp J.O

2011-01-01

It has generally been assumed that the bioreduction of hexavalent uranium in groundwater systems will result in the precipitation of immobile uraninite (UO2). In order to explore the form and stability of uranium immobilized under these conditions we introduced lactate (15 mM for 3 months) into flow through columns containing sediments derived from a former uranium processing site at Old Rifle CO. This resulted in metal reducing conditions as evidenced by concurrent uranium uptake and iron re...

Uranium speciation and stability after reductive immobilization in sediments

OpenAIRE

Sharp, Jonathan O.; Schofield, Eleanor J.; Lezama-Pacheco, Juan S.; Webb, Sam; Ulrich, Kai-Uwe; Blue, Lisa; Chinni, Satyavani; Veeramani, Harish; Junier, Pilar; Margot-Roquier, Camille; Suvorova Buffat, Elena; Tebo, Bradley M.; Giammar, Daniel E.; Bargar, John R.; Bernier-Latmani, Rizlan

2011-01-01

It has generally been assumed that the bioreduction of hexavalent uranium in groundwater systems will result in the precipitation of immobile uraninite (UO2). In order to explore the form and stability of uranium immobilized under these conditions, we introduced lactate (15 mM for 3 months) into flow-through columns containing sediments derived from a former uranium-processing site at Old Rifle, CO. This resulted in metal-reducing conditions as evidenced by concurrent uranium uptake and iron ...

Immobilization of Mucor miehei Lipase onto Macroporous Aminated Polyethersulfone Membrane for Enzymatic Reactions

NARCIS (Netherlands)

Handayani, Nurrahmi; Loos, Katja; Wahyuningrum, Deana; Buchari, [No Value; Zulfikar, Muhammad Ali

2012-01-01

Immobilization of enzymes is one of the most promising methods in enzyme performance enhancement, including stability, recovery, and reusability. However, investigation of suitable solid support in enzyme immobilization is still a scientific challenge. Polyethersulfone (PES) and aminated PES

PREPARATION AND CHARACTERIZATION OF BIOCATALYSTS BASED ON IMMOBILIZED GLYCOSIDASES

Directory of Open Access Journals (Sweden)

O. L. Meshcheriakova

2014-01-01

Full Text Available Summary. Enzymes subclass glycosidases cleaving poly- and oligosaccharides to simple sugars, are of great practical importance for a variety of industries. Such enzymes include α-L-fucosidase and β-fructofuranosidase. α-L-fucosidase splits fucoidan kelp to fucose and fucooligosaccharides. Fucose has prebiotic, immunotropic action, and a wide spectrum of biological activity in vertebrates, fucooligosaccharides - antioxidant and prebiotic properties. In this regard, and fucose polymers may be demanded in the food, feed and pharmaceutical industry. β-fructofuranosidase sucrose hydrolysis with the formation of invert syrup high quality and biological value that is of interest to the sugar industry. In order to intensify the processes of hydrolysis of fucoidan and sucrose due to the higher stability and reusability of enzyme preparations carried immobilization α-L-fucosidase on chitosan and β-fructofuranosidase of ion exchange brand FIBAN A-6 adsorption method. Activity of the immobilized α-L-fucosidase and β-fructofuranosidase were 80 and 70% of the activity of the free enzyme, respectively. Found that immobilized β-fructofuranosidase exhibits maximal activity at pH 4,0-4,1, the immobilized α-L-fucosidase - at pH 7,0. The optimal pH of immobilized enzymes similar to those for the free enzyme. Optimal temperature hydrolysis substrates immobilized α-L-fucosidase and β-fructofuranosidase was 50 and 70 ° C respectively, 10 ° C and 20 ° C higher compared to free enzymes. Studies have shown sufficient stability of immobilized glycosidases, so at 4-fold using their enzymatic activity decreased by 1.5 times; Biocatalysts obtained in storage in the refrigerator for 4-6 months retained 80% of the catalytic activity of enzymes.

Effects of immobilization on spermiogenesis

Science.gov (United States)

Meitner, E. R.

1980-01-01

The influence of immobilization stress on spermiogenesis in rats was investigated. After 96 hour immobilization, histological changes began to manifest themselves in the form of practically complete disappearance of cell population of the wall of seminiferous tubule as well as a markedly increased number of cells with pathologic mitoses. Enzymological investigations showed various changes of activity (of acid and alkaline phosphatase and nonspecific esterase) in the 24, 48, and 96 hour immobilization groups.

Condition of pro-oxidant and antioxidant systems in guinea pigs’ lungs under the condition of immobilization stress

Directory of Open Access Journals (Sweden)

Mykhailo Stepanovych Reheda

2017-11-01

Full Text Available We have investigated the results of alterations in indices of pro-oxidant (conjugated diene and malondialdehyde and antioxidant (superoxide dismutase, ceruloplasmin, catalase systems in guinea pigs’ lungs  under the conditions of immobilization stress. The experiment was conducted on 40 female guinea pigs weighing 0.18-0.20 kg. The animals were divided into 4 groups, each contained 10 guinea pigs: I – intact guinea pigs ( control, II–guinea pigs with model of IS on1st day of experiment;Ш–animals on 2nd  day of experiment;IV- group of animals on 34th day of experimental model of IS. The results of our experimental work showed  a significant accumulation of lipid peroxidation products in the lung`s tissure in different periods ( on 1st, 2nd and 34th days of immobilization stress. The state of antioxidant defence was characterized by moderate decrease of inzymes activity (superoxide dismutase, catalase and ceruloplasmin. disorders of balance between pro-oxidant and antioxidant systems couse oxidative stress development.

Characteristics of an immobilized yeast cell system using very high gravity for the fermentation of ethanol.

Science.gov (United States)

Ji, Hairui; Yu, Jianliang; Zhang, Xu; Tan, Tianwei

2012-09-01

The characteristics of ethanol production by immobilized yeast cells were investigated for both repeated batch fermentation and continuous fermentation. With an initial sugar concentration of 280 g/L during the repeated batch fermentation, more than 98% of total sugar was consumed in 65 h with an average ethanol concentration and ethanol yield of 130.12 g/L and 0.477 g ethanol/g consumed sugar, respectively. The immobilized yeast cell system was reliable for at least 10 batches and for a period of 28 days without accompanying the regeneration of Saccharomyces cerevisiae inside the carriers. The multistage continuous fermentation was carried out in a five-stage column bioreactor with a total working volume of 3.75 L. The bioreactor was operated for 26 days at a dilution rate of 0.015 h(-1). The ethanol concentration of the effluent reached 130.77 g/L ethanol while an average 8.18 g/L residual sugar remained. Due to the high osmotic pressure and toxic ethanol, considerable yeast cells died without regeneration, especially in the last two stages, which led to the breakdown of the whole system of multistage continuous fermentation.

Remote handling in the Plutonium Immobilization Project: Plutonium conversion and first stage immobilization

International Nuclear Information System (INIS)

Brault, J.R.

2000-01-01

Since the break up of the Soviet Union at the end of the Cold War, the United States and Russia have been negotiating ways to reduce their nuclear stockpiles. Economics is one of the reasons behind this, but another important reason is safeguarding these materials from unstable organizations and countries. With the downsizing of the nuclear stockpiles, large quantities of plutonium are being declared excess and must be safely disposed of. The Savannah River Site (SRS) has been selected as the site where the immobilization facility will be located. Conceptual design and process development commenced in 1998. SRS will immobilize excess plutonium in a ceramic waste form and encapsulate it in vitrified high level waste in the Defense Waste Processing Facility (DWPF) canister. These canisters will then be interred in the national repository at Yucca Mountain, New Mexico. The facility is divided into three distinct operating areas: Plutonium Conversion, First Stage Immobilization, and Second Stage Immobilization. This paper will discuss the first two operations

Amperometric Determination of Glucose at Parts per Million Levels with Immobilized Glucose Oxidase.

Science.gov (United States)

Sittampalam, G.; Wilson, G. S.

1982-01-01

An experiment on the operation and utility of an amperometric immobilized enzyme electrode (or probe) is described, including advantages of the experiment, equipment, reagents, preparation of phosphate buffer, enzyme immobilization techniques, laboratory procedures, precautions, and discussion of experimental results. (SK)

Availability and improvement of a vacuum-type immobilization device in pediatric CT

International Nuclear Information System (INIS)

Tani, Shoji; Mizuno, Naoto; Abe, Syuji

2002-01-01

The essential factors for an immobilization device in pediatric CT are absence of artifacts, safety, no disturbance of the patient's sedation, and ease of handling. We evaluated the suitability of a commercially available vacuum-type immobilization device designed for radiation therapy (Vac-Lok) that meets these requisites. There were no artifacts in scans of the water phantom. The device easily immobilized the patient, was quick to release, and was superior to previous immobilization systems, according to replies to a questionnaire administered to physicians, technologists, and nurses. Schedule delays were reduced by using this device to examine sedated patients (up to 1 year of age). Despite these advantages, the device was too small to immobilize both extremities together when examining older patients. In order to overcome this problem, we invented a special immobilization device for pediatric CT. The new device could be applied to taller patients, up to 85 cm in height (the average height of 2-year-old infants), and was able to contribute to efficient utilization of the examination room. (author)

Applications of polymers for biomolecule immobilization in electrochemical biosensors

International Nuclear Information System (INIS)

Teles, F.R.R.; Fonseca, L.P.

2008-01-01

Polymers are becoming inseparable from biomolecule immobilization strategies and biosensor platforms. Their original role as electrical insulators has been progressively substituted by their electrical conductive abilities, which opens a new and broad scope of applications. In addition, recent advances in diagnostic chips and microfluidic systems, together with the requirements of mass-production technologies, have raised the need to replace glass by polymeric materials, which are more suitable for production through simple manufacturing processes. Conducting polymers (CPs), in particular, are especially amenable for electrochemical biosensor development for providing biomolecule immobilization and for rapid electron transfer. It is expected that the combination of known polymer substrates, but also new transducing and biocompatible interfaces, with nanobiotechnological structures, like nanoparticles, carbon nanotubes (CNTs) and nanoengineered 'smart' polymers, may generate composites with new and interesting properties, providing higher sensitivity and stability of the immobilized molecules, thus constituting the basis for new and improved analytical devices for biomedical and other applications. This review covers the state-of-the-art and main novelties about the use of polymers for immobilization of biomolecules in electrochemical biosensor platforms

Stabilization of {alpha}-amylase by using anionic surfactant during the immobilization process

Energy Technology Data Exchange (ETDEWEB)

El-Batal, A.I. [National Center for Radiation Research and Technology, P.O. Box 29, Nasr City, Cairo (Egypt); Atia, K.S. [Nuclear Research Center, Radioisotopes Applications Division, Abo-Zable, P.O. Box 13759, Cairo (Egypt)]. E-mail: ks_atia@yahoo.com; Eid, M. [National Center for Radiation Research and Technology, P.O. Box 29, Nasr City, Cairo (Egypt)

2005-10-01

This work describes the entrapment of {alpha}-amylase into butylacrylate-acrylic acid copolymer (BuA/AAc) using {gamma} irradiation. The effect of an anionic surfactant (AOT), the reuse efficiency, and kinetic behavior of immobilized {alpha}-amylase were studied. Covering of {alpha}-amylase with bis-(2-ethylhexyl)sulfosuccinate sodium salt (AOT) made the enzyme more stable than the uncovered form. The hydrolytic activity of the pre-coated immobilized {alpha}-amylase was increased below the critical micelle concentration (cmc) (10mmol/L). The results showed an increase in the relative activity with increase in the degree of hydration. The pre-coated immobilized {alpha}-amylase showed a higher k{sub cat}/K{sub m} and lower activation energy compared to the free and uncoated-immobilized preparation, respectively. The results suggest that the immobilization of {alpha}-amylase is a potentially useful approach for commercial starch hydrolysis in two-phase systems.

Stabilization of α-amylase by using anionic surfactant during the immobilization process

International Nuclear Information System (INIS)

El-Batal, A.I.; Atia, K.S.; Eid, M.

2005-01-01

This work describes the entrapment of α-amylase into butylacrylate-acrylic acid copolymer (BuA/AAc) using γ irradiation. The effect of an anionic surfactant (AOT), the reuse efficiency, and kinetic behavior of immobilized α-amylase were studied. Covering of α-amylase with bis-(2-ethylhexyl)sulfosuccinate sodium salt (AOT) made the enzyme more stable than the uncovered form. The hydrolytic activity of the pre-coated immobilized α-amylase was increased below the critical micelle concentration (cmc) (10mmol/L). The results showed an increase in the relative activity with increase in the degree of hydration. The pre-coated immobilized α-amylase showed a higher k cat /K m and lower activation energy compared to the free and uncoated-immobilized preparation, respectively. The results suggest that the immobilization of α-amylase is a potentially useful approach for commercial starch hydrolysis in two-phase systems

Immobilized cells of Candida rugosa possessing fumarase activity

Energy Technology Data Exchange (ETDEWEB)

Yang, L.; Zhone, L.

1980-01-01

Immobilized cells of C. rugosa that possessed fumarase activity were prepared by different methods; the most active immobilized cells were entrapped in polyacrylamide gels. The effects of pH temperature, and divalent cations on the fumarase activity of both immobilized and native cells were the same. Mn/sup 2 +/, Mg/sup 2 +/, Ca/sup 2 +/, and Fe/sup 2 +/ did not protect the immobilized enzyme against thermal inactivation. The activity of immobilized fumarase remained constant during 91 days of storage of 4-6 degrees. The immobilized cell column was used for the continuous production of L-malic acid from 1M fumarate at 30 degrees and pH 8.5. The immobilized column operated steadily for 2 months. Half life of the immobilized fumarase at 30 degrees was 95 days.

Immobilization needs and technology programs

International Nuclear Information System (INIS)

Gray, L.W.; Kan, T.; Shaw, H.; Armantrout, G.

1995-01-01

In the aftermath of the Cold War, the US and Russia agreed to large reductions in nuclear weapons. To aid in the selection of long-term management options, DOE has undertaken a multifaceted study to select options for storage and disposition of plutonium in keeping with US policy that plutonium must be subjected to the highest standards of safety, security, and accountability. One alternative being considered is immobilization. To arrive at a suitable immobilization form, we first reviewed published information on high-level waste immobilization technologies and identified 72 possible plutonium immobilization forms to be prescreened. Surviving forms were further screened using multi-attribute utility analysis to determine the most promising technology families. Promising immobilization families were further evaluated to identify chemical, engineering, environmental, safety, and health problems that remain to be solved prior to making technical decisions as to the viability of using the form for long- term disposition of plutonium. From this evaluation, a detailed research and development plan has been developed to provide answers to these remaining questions

The immobilization of organic liquid wastes

International Nuclear Information System (INIS)

Greenhalgh, W.O.

1986-01-01

This report describes a portland cement immobilization process for the disposal treatment of radioactive organic liquid wastes which would be generated in a FFTF fuels reprocessing line. An incineration system already on-hand was determined to be too costly to operate for the 100 to 400 gallons per year organic liquid. Organic test liquids were dispersed into an aqueous phosphate liquid using an emulsifier. A total of 109 gallons of potential and radioactive aqueous immiscible organic liquid wastes from Hanford 300 Area operations were solidified with portland cement and disposed of as solid waste during a 3 month test program with in-drum mixers. Waste packing efficiencies varied from 32 to 40% and included pump oils, mineral spirits, and TBP-NPH type solvents

Continuous citric acid production in repeated-fed batch fermentation by Aspergillus niger immobilized on a new porous foam.

Science.gov (United States)

Yu, Bin; Zhang, Xin; Sun, Wenjun; Xi, Xun; Zhao, Nan; Huang, Zichun; Ying, Zhuojun; Liu, Li; Liu, Dong; Niu, Huanqing; Wu, Jinglan; Zhuang, Wei; Zhu, Chenjie; Chen, Yong; Ying, Hanjie

2018-03-24

The efficiency of current methods for industrial production of citric acid is limited. To achieve continuous citric acid production with enhanced yield and reduced cost, immobilized fermentation was employed in an Aspergillus niger 831 repeated fed-batch fermentation system. We developed a new type of material (PAF201), which was used as a carrier for the novel adsorption immobilization system. Hydrophobicity, pore size and concentration of carriers were researched in A. niger immobilization. The efficiency of the A. niger immobilization process was analyzed by scanning electron microscopy. Then eight-cycle repeated fed-batch cultures for citric acid production were carried out over 600 h, which showed stable production with maximum citric acid concentrations and productivity levels of 162.7 g/L and 2.26 g L -1  h -1 , respectively. Compared with some other literatures about citric acid yield, PAF201 immobilization system is 11.3% higher than previous results. These results indicated that use of the new adsorption immobilization system could greatly improve citric acid productivity in repeated fed-batch fermentation. Moreover, these results could provide a guideline for A.niger or other filamentous fungi immobilization in industry. Copyright © 2018 Elsevier B.V. All rights reserved.

Continuous production of chitooligosaccharides by an immobilized enzyme in a dual-reactor system

DEFF Research Database (Denmark)

Santos-Moriano, Paloma; Woodley, John; Plou, Francisco J.

2016-01-01

A chitosanolytic activity found in a commercial α-amylase from Bacillus amylolyquefaciens (BAN) was covalently immobilized onto glyoxal agarose beads (25% recovery of activity) and assessed for the continuous production of chitooligosaccharides (COS). The immobilization did not change the reactio......, the productivity of the PBR at the lowest dilution rate was 37 gCOS L−1 h−1, with a conversion yield of 73%. In contrast, at the highest dilution rate, the productivity was nearly 200 gCOS L−1 h−1, but the conversion yield dropped to around 40%....

Implementation of immobilization accessories for positioning of small animals for radiation therapy

International Nuclear Information System (INIS)

Vettorato, M.C.; Girotto, C.H.; Fogaça, J.L.; Vulcano, L.C.; Fernandes, M.A.R.

2017-01-01

Radiation therapy is a modality that is presenting great advances in veterinary medicine worldwide. In Brazil, this therapeutic option is underachieved. The success of this method depends on several factors, including the use of appropriate accessories for protection and immobilization of patients. For the immobilization of small animals during treatment, in addition to sedation and anesthesia, immobilizing accessories, similar to those used in human radiotherapy, are used. This study aimed to present proposals for immobilizing accessories adapted to the positioning of small animals in order to be used in radiotherapy planning. In order to achieve results, accessories were made and tested in a living animal simulating a radiotherapy planning, which proved to be favorable to use in positioning small animals undergoing radiotherapy and for implementation processes. (author)

Implementation of immobilization accessories for positioning of small animals for radiation therapy

Energy Technology Data Exchange (ETDEWEB)

Vettorato, M.C.; Girotto, C.H.; Fogaça, J.L.; Vulcano, L.C.; Fernandes, M.A.R., E-mail: m_vettorato@hotmail.com [Universidade Estadual Paulista Júlio de Mesquita Filho (UNESP), Botucatu, SP (Brazil)

2017-11-15

Radiation therapy is a modality that is presenting great advances in veterinary medicine worldwide. In Brazil, this therapeutic option is underachieved. The success of this method depends on several factors, including the use of appropriate accessories for protection and immobilization of patients. For the immobilization of small animals during treatment, in addition to sedation and anesthesia, immobilizing accessories, similar to those used in human radiotherapy, are used. This study aimed to present proposals for immobilizing accessories adapted to the positioning of small animals in order to be used in radiotherapy planning. In order to achieve results, accessories were made and tested in a living animal simulating a radiotherapy planning, which proved to be favorable to use in positioning small animals undergoing radiotherapy and for implementation processes. (author)

Biodegradation of chlorobenzene using immobilized crude extracts ...

African Journals Online (AJOL)

SERVER

2007-10-04

Oct 4, 2007 ... immobilized crude extracts were reused for all other experiments and found that immobilization .... India which are of analytical reagent grade. .... 9. 60. 3. 1. Figure 3. Degradation of chlorobenzene by immobilized crude.

Utilization of immobilized urease for waste water treatment

Science.gov (United States)

Husted, R. R.

1974-01-01

The feasibility of using immobilized urease for urea removal from waste water for space system applications is considered, specifically the elimination of the urea toxicity problem in a 30-day Orbiting Frog Otolith (OFO) flight experiment. Because urease catalyzes the hydrolysis of urea to ammonia and carbon dioxide, control of their concentrations within nontoxic limits was also determined. The results of this study led to the use of free urease in lieu of the immobilized urease for controlling urea concentrations. An ion exchange resin was used which reduced the NH3 level by 94% while reducing the sodium ion concentration only 10%.

Development of a phantom to evaluate the positioning accuracy of patient immobilization systems using thermoplastic mask and polyurethane cradle.

Science.gov (United States)

Inata, Hiroki; Semba, Takatoshi; Itoh, Yoshihiro; Kuribayashi, Yuta; Murayama, Suetoshi; Nishizaki, Osamu; Araki, Fujio

2012-07-01

The purpose of this study was to develop a new phantom to evaluate the positioning accuracy of patient immobilization systems. The phantom was made of papers formed into a human shape, paper clay, and filling rigid polyester. Acrylonitrile butadiene styrene (ABS) pipes were inserted at anterior-posterior (A-P) and right-left (R-L) directions in the phantom to give static load by pulling ropes through the pipes. First, the positioning precision of the phantom utilizing a target locating system (TLS) was evaluated by moving the phantom on a couch along inferior-superior (I-S), A-P, and R-L directions in a range from -5 mm to +5 mm. The phantom's positions detected with the TLS were compared with values measured by a vernier caliper. Second, the phantom movements in a tensile test were chosen from patient movements determined from 15 patients treated for intracranial lesions and immobilized with a thermoplastic mask and polyurethane cradle. The phantom movement was given by minimum or maximum values of patient movements in each direction. Finally, the relationship between phantom movements and the static load in the tensile test was characterized from measurements using the new phantom and the TLS. The differences in all positions between the vernier caliper measurement and the TLS detected values were within 0.2 mm with frequencies of 100%, 95%, and 90% in I-S, A-P, and R-L directions, respectively. The phantom movements according to patient movements in clinical application in I-S, A-P, and R-L directions were within 0.58 mm, 0.94 mm, and 0.93 mm from the mean value plus standard deviation, respectively. The regression lines between the phantom movements and static load were given by y = 0.359x, y = 0.241x, and y = 0.451x in I-S, A-P, and R-L directions, respectively, where x is the phantom movement (mm) and y is the static load (kgf). The relationship between the phantom movements and static load may represent the performance of inhibiting patient movements, so the

Modeling Substrate Utilization, Metabolite Production, and Uranium Immobilization in Shewanella oneidensis Biofilms

Directory of Open Access Journals (Sweden)

Ryan S. Renslow

2017-06-01

Full Text Available In this study, we developed a two-dimensional mathematical model to predict substrate utilization and metabolite production rates in Shewanella oneidensis MR-1 biofilm in the presence and absence of uranium (U. In our model, lactate and fumarate are used as the electron donor and the electron acceptor, respectively. The model includes the production of extracellular polymeric substances (EPS. The EPS bound to the cell surface and distributed in the biofilm were considered bound EPS (bEPS and loosely associated EPS (laEPS, respectively. COMSOL® Multiphysics finite element analysis software was used to solve the model numerically (model file provided in the Supplementary Material. The input variables of the model were the lactate, fumarate, cell, and EPS concentrations, half saturation constant for fumarate, and diffusion coefficients of the substrates and metabolites. To estimate unknown parameters and calibrate the model, we used a custom designed biofilm reactor placed inside a nuclear magnetic resonance (NMR microimaging and spectroscopy system and measured substrate utilization and metabolite production rates. From these data we estimated the yield coefficients, maximum substrate utilization rate, half saturation constant for lactate, stoichiometric ratio of fumarate and acetate to lactate and stoichiometric ratio of succinate to fumarate. These parameters are critical to predicting the activity of biofilms and are not available in the literature. Lastly, the model was used to predict uranium immobilization in S. oneidensis MR-1 biofilms by considering reduction and adsorption processes in the cells and in the EPS. We found that the majority of immobilization was due to cells, and that EPS was less efficient at immobilizing U. Furthermore, most of the immobilization occurred within the top 10 μm of the biofilm. To the best of our knowledge, this research is one of the first biofilm immobilization mathematical models based on experimental

Immobilized/P25/DSAT and Immobilized/Kronos/DSAT on Photocatalytic Degradation of Reactive Red 4 Under Fluorescent Light

Directory of Open Access Journals (Sweden)

Azami M. S.

2016-01-01

Full Text Available In this work, photocatalytic degradation of Reactive Red 4 (RR4 using immobilized P25 and kronos were performed under fluorescent light sources. The photocatalysis activity for both catalysts was investigated under fluorescent lamp source which consist UV and Visible light. The effect of various parameters such as initial concentration, initial pH and strenght of immobilized plate were studied. The result showed that 90% of RR4 dye was degrade in 1 hr using immobilized/kronos/DSAT at 100 mg L-1 of RR4 dye while 81% degradation was achieved by immobilized/P25/DSAT at the same condition. The lowest pH showed the higher photocatalytic activity. Hence, the effect of dye concentration and pH on the photocatalysis study can be related with the behavior of environmental pollution. The low strength showed by immobilized/P25/DSAT where it remain 37 % as compared with strength of immobilized/kronos/DSAT (52 wt.%. For the future work, the polymer binder like Polyvinyl alcohol (PVA, Polyethylene glycol (PEG, and others polymers can be apply in immobilized study to overcome the strength problem.

Herbaceous plants as filters: Immobilization of particulates along urban street corridors

International Nuclear Information System (INIS)

Weber, Frauke; Kowarik, Ingo; Säumel, Ina

2014-01-01

Among air pollutants, particulate matter (PM) is considered to be the most serious threat to human health. Plants provide ecosystem services in urban areas, including reducing levels of PM by providing a surface for deposition and immobilization. While previous studies have mostly addressed woody species, we focus on herbaceous roadside vegetation and assess the role of species traits such as leaf surface roughness or hairiness for the immobilization of PM. We found that PM deposition patterns on plant surfaces reflect site-specific traffic densities and that strong differences in particulate deposition are present among species. The amount of immobilized PM differed according to particle type and size and was related to specific plant species traits. Our study suggests that herbaceous vegetation immobilizes a significant amount of the air pollutants relevant to human health and that increasing biodiversity of roadside vegetation supports air filtration and thus healthier conditions along street corridors. -- Highlights: • We assessed PM immobilization by common urban herbaceous roadside species. • PM deposition was related to traffic density and plant species traits. • Amount of PM deposited differed according to particle type and size. • Increasing biodiversity of roadside vegetation supports air filtration. -- Herbaceous urban roadside vegetation immobilizes particulate matter relevant to human health, thus supporting healthier conditions next to busy roads

Plutonium Immobilization Can Loading Preliminary Specifications

Energy Technology Data Exchange (ETDEWEB)

Kriikku, E.

1998-11-25

This report discusses the Plutonium Immobilization can loading preliminary equipment specifications and includes a process block diagram, process description, equipment list, preliminary equipment specifications, plan and elevation sketches, and some commercial catalogs. This report identifies loading pucks into cans and backfilling cans with helium as the top priority can loading development areas.

Immobilized high-level waste interim storage alternatives generation and analysis and decision report

International Nuclear Information System (INIS)

CALMUS, R.B.

1999-01-01

This report presents a study of alternative system architectures to provide onsite interim storage for the immobilized high-level waste produced by the Tank Waste Remediation System (TWRS) privatization vendor. It examines the contract and program changes that have occurred and evaluates their impacts on the baseline immobilized high-level waste (IHLW) interim storage strategy. In addition, this report documents the recommended initial interim storage architecture and implementation path forward

Preliminary assessment of modified borosilicate glasses for chromium and ruthenium immobilization

Energy Technology Data Exchange (ETDEWEB)

Farid, Osama M. [Reactors Department, Nuclear Research Center, Atomic Energy Authority of Egypt, P.O. 13759, Inshas, Cairo (Egypt); Centre of Nuclear Engineering (CNE), Department of Materials, Imperial College London, London, SW7 2BP (United Kingdom); Abdel Rahman, R.O., E-mail: alaarehab@yahoo.com [Hot Laboratory Center, Atomic Energy Authority of Egypt, P.O. 13759, Inshas, Cairo (Egypt)

2017-01-15

The feasibility of using modified alkali borosilicate glasses for ruthenium and chromium immobilization is preliminary assessed by investigating the immobilization system structure under normal conditions. Within this context, reference alkali borosilicate, and simulated Magnox-modified glasses were prepared and studied. The results indicate that ruthenium is immobilized in the vitreous structure as encapsulated RuO{sub 2} crystallites that act as seeds for heterogeneous nucleation of other crystalline phases. The presence of Zn, as modifier, has contributed to chromium immobilization in zincochromite spinel structure, whereas Ca is accommodated in the vitreous structure. Immobilization performance was evaluated by conducting conservative static leach test and studying the leached glass. Leached glass morphology was altered, where near surface reference glass is leached over 400 nm and simulated Magnox-modified sample is altered over 300 nm. Normalized release rates are within normal range for borosilicate material. For simulated Magnox-modified sample, Ca and alkali structural element, i.e. Na and Li, are leached via ion-exchange reaction. The ion-exchanged fraction equals 1.06 × 10{sup −8} mol/m{sup 2} s and chromium has slightly lower normalized release rate value than ruthenium. - Highlights: • The presence of modifiers and waste oxides led to localized de-vitrification. • Ruthenium is encapsulated within the vitreous glass network as RuO{sub 2} crystals. • Chromium is immobilized within the zincochromite spinel structure. • Pitting and cracks induced by leaching did not affect the immobilization performance.

Experimental joint immobilization in guinea pigs. Effects on the knee joint

Science.gov (United States)

Marcondesdesouza, J. P.; Machado, F. F.; Sesso, A.; Valeri, V.

1980-01-01

In young and adult guinea pigs, the aftermath experimentally induced by the immobilization of the knee joint in hyperextended forced position was studied. Joint immobilization which varied from one to nine weeks was attained by plaster. Eighty knee joints were examined macro and microscopically. Findings included: (1) muscular hypotrophy and joint stiffness in all animals, directly proportional to the length of immobilization; (2) haemoarthrosis in the first week; (3) intra-articular fibrous tissue proliferation ending up with fibrous ankylosis; (4) hyaline articular cartilage erosions; (5) various degrees of destructive menisci changes. A tentative explanation of the fibrous tissue proliferation and of the cartilage changes is offered.

Properties of Immobilized Candida antarctica Lipase B on Highly Macroporous Copolymer

International Nuclear Information System (INIS)

Handayani, N.; Achmad, S.; Wahyuningrum, D.

2011-01-01

In spite of their excellent catalytic properties, enzymes should be improved before their implementation both in industrial and laboratorium scales. Immobilization of enzyme is one of the ways to improve their properties. Candida antarctica lipase B (Cal-B) has been reported in numerous publications to be a particularly useful enzyme catalizing in many type of reaction including regio- and enantio- synthesis. For this case, cross-linking of immobilized Cal-B with 1,2,7,8 diepoxy octane is one of methods that proved significantly more stable from denaturation by heat, organic solvents, and proteolysis than lyophilized powder or soluble enzymes. More over, the aim of this procedure is to improve the activity and reusability of lipase. Enzyme kinetics test was carried out by transesterification reaction between 4-nitrophenyl acetate (pNPA) and methanol by varying substrate concentrations, and the result is immobilized enzymes follows the Michaelis-Menten models and their activity is match with previous experiment. Based on the V max values, the immobilized enzymes showed higher activity than the free enzyme. Cross-linking of immobilized lipase indicate that cross-linking by lower concentration of cross-linker, FIC (immobilized lipase that was incubated for 24 h) gave the highest activity and cross-linking by higher concentration of cross-linker, PIC (immobilized lipase that was incubated for 2 h) gives the highest activity. However, pore size and saturation level influenced their activity. (author)

Design-Only Conceptual Design Report: Plutonium Immobilization Plant

International Nuclear Information System (INIS)

DiSabatino, A.; Loftus, D.

1999-01-01

This design-only conceptual design report was prepared to support a funding request by the Department of Energy Office of Fissile Materials Disposition for engineering and design of the Plutonium Immobilization Plant, which will be used to immobilize up to 50 tonnes of surplus plutonium. The siting for the Plutonium Immobilization Plant will be determined pursuant to the site-specific Surplus Plutonium Disposition Environmental Impact Statement in a Plutonium Deposition Record of Decision in early 1999. This document reflects a new facility using the preferred technology (ceramic immobilization using the can-in-canister approach) and the preferred site (at Savannah River). The Plutonium Immobilization Plant accepts plutonium from pit conversion and from non-pit sources and, through a ceramic immobilization process, converts the plutonium into mineral-like forms that are subsequently encapsulated within a large canister of high-level waste glass. The final immobilized product must make the plutonium as inherently unattractive and inaccessible for use in nuclear weapons as the plutonium in spent fuel from commercial reactors and must be suitable for geologic disposal. Plutonium immobilization at the Savannah River Site uses: (1) A new building, the Plutonium Immobilization Plant, which will convert non-pit surplus plutonium to an oxide form suitable for the immobilization process, immobilize plutonium in a titanate-based ceramic form, place cans of the plutonium-ceramic forms into magazines, and load the magazines into a canister; (2) The existing Defense Waste Processing Facility for the pouring of high-level waste glass into the canisters; and (3) The Actinide Packaging and Storage Facility to receive and store feed materials. The Plutonium Immobilization Plant uses existing Savannah River Site infra-structure for analytical laboratory services, waste handling, fire protection, training, and other support utilities and services. The Plutonium Immobilization Plant

Immobilization of Pseudomonas fluorescens lipase on hydrophobic supports and application in biodiesel synthesis by transesterification of vegetable oils in solvent-free systems.

Science.gov (United States)

Lima, Lionete N; Oliveira, Gladson C; Rojas, Mayerlenis J; Castro, Heizir F; Da Rós, Patrícia C M; Mendes, Adriano A; Giordano, Raquel L C; Tardioli, Paulo W

2015-04-01

This work describes the preparation of biocatalysts for ethanolysis of soybean and babassu oils in solvent-free systems. Polystyrene, Amberlite (XAD-7HP), and octyl-silica were tested as supports for the immobilization of Pseudomonas fluorescens lipase (PFL). The use of octyl-silica resulted in a biocatalyst with high values of hydrolytic activity (650.0 ± 15.5 IU/g), immobilization yield (91.3 ± 0.3 %), and recovered activity (82.1 ± 1.5 %). PFL immobilized on octyl-silica was around 12-fold more stable than soluble PFL, at 45 °C and pH 8.0, in the presence of ethanol at 36 % (v/v). The biocatalyst provided high vegetable oil transesterification yields of around 97.5 % after 24 h of reaction using babassu oil and around 80 % after 48 h of reaction using soybean oil. The PFL-octyl-silica biocatalyst retained around 90 % of its initial activity after five cycles of transesterification of soybean oil. Octyl-silica is a promising support that can be used to immobilize PFL for subsequent application in biodiesel synthesis.

US Department of Energy Plutonium Stabilization and Immobilization Workshop, December 12-14, 1995: Final proceedings

Energy Technology Data Exchange (ETDEWEB)

NONE

1996-05-01

The purpose of the workshop was to foster communication within the technical community on issues surrounding stabilization and immobilization of the Department`s surplus plutonium and plutonium- contaminated wastes. The workshop`s objectives were to: build a common understanding of the performance, economics and maturity of stabilization and immobilization technologies; provide a system perspective on stabilization and immobilization technology options; and address the technical issues associated with technologies for stabilization and immobilization of surplus plutonium and plutonium- contaminated waste. The papers presented during this workshop have been indexed separately.

Protein-based inverse opals: A novel support for enzyme immobilization.

Science.gov (United States)

Jiang, Yanjun; Sun, Wenya; Wang, Yaping; Wang, Lihui; Zhou, Liya; Gao, Jing; He, Ying; Ma, Li; Zhang, Xu

2017-01-01

In this study, protein-based inverse opals were prepared for the first time by using the colloidal crystal templating method. The preparation process involved three steps including filling the templates with protein molecules, crosslinking, and template removal. The obtained inverse opals were used to immobilize Penicillin G acylase (PGA) because of its intrinsic biocompatible property. The immobilization process was optimized and the properties of the immobilized PGA (PGA@IO) were investigated. PGA@IO exhibited improved thermal and pH stability compared with its free counterpart. After reusing nine times, it retained 70% of the initial activity. Besides, the PGA@IO retained high activity during the hydrolysis reactions in continuous catalysis in packed-bed reactor (PBR) after 15 days. Copyright © 2016 Elsevier Inc. All rights reserved.

Increase in H-reflex gain following 1 week of immobilization

DEFF Research Database (Denmark)

Jensen, Jesper Lundbye; Sørensen, Mie; Nielsen, Jens Bo

It is well established that motor experience induces structural and functional plasticity within the central nervous system. It is less well investigated whether reduced motor activity in relation to immobilization is also associated with plastic neuronal changes. The present experiment examined ...... removal all measurements had returned to preimmobilization levels. These results show that immobilization of only one week duration is associated with reversible adaptive changes in the gain of the central part of the monosynaptic stretch reflex....

Radiation immobilization of catalase and its application

International Nuclear Information System (INIS)

Wang Guanghui; Ha Hongfei; Wang Xia; Wu Jilan

1988-01-01

Catalase was immobilized by a chemical method on porous polyacrylamide particles produced by radiation polymerization of acrylamide monomer at low temperature (-78 0 C). Activity of immobilized catalase was enhanced distinctly by joining a chemical arm to the support. The method of recovery of catalase activity on immobilized polymer was found by soaking it in certain buffer. The treatment of H 2 O 2 both in aqueous solution and alcoholic solution by using the immobilized catalase was performed. (author)

Graphene immobilized enzyme/polyethersulfone mixed matrix membrane: Enhanced antibacterial, permeable and mechanical properties

International Nuclear Information System (INIS)

Duan, Linlin; Wang, Yuanming; Zhang, Yatao; Liu, Jindun

2015-01-01

Graphical abstract: - Highlights: • Lysozyme was immobilized on the surface of graphene oxide (GO) and reduced GO (RGO). • The novel hybrid membranes based on lysozyme and graphene were fabricated firstly. • These membranes showed good antibacterial and mechanical performance. - Abstract: Enzyme immobilization has been developed to address lots of issues of free enzyme, such as instability, low activity and difficult to retain. In this study, graphene was used as an ideal carrier for lysozyme immobilization, including graphene oxide (GO) immobilized lysozyme (GO-Ly) and chemically reduced graphene oxide (CRGO) immobilized lysozyme (CRGO-Ly). Herein, lysozyme as a bio-antibacterial agent has excellent antibacterial performance and the products of its catalysis are safety and nontoxic. Then the immobilized lysozyme materials were blended into polyethersulfone (PES) casting solution to prepare PES ultrafiltration membrane via phase inversion method. GO and CRGO were characterized by Fourier transform infrared spectroscopy (FTIR), Ultraviolet–visible spectrum (UV), X-ray diffraction (XRD), and transmission electron microscopy (TEM) and the immobilized lysozyme composites were observed by fluorescent microscopy. The results revealed that GO and CRGO were successfully synthesized and lysozyme was immobilized on their surfaces. The morphology, hydrophilicity, mechanical properties, separation properties and antibacterial activity of the hybrid membranes were characterized in detail. The hydrophilicity, water flux and mechanical strength of the hybrid membranes were significantly enhanced after adding the immobilized lysozyme. In the antibacterial experiment, the hybrid membranes exhibited an effective antibacterial performance against Escherichia coli (E. coli).

The removal of thermo-tolerant coliform bacteria by immobilized waste stabilization pond algae.

Science.gov (United States)

Pearson, H W; Marcon, A E; Melo, H N

2011-01-01

This study investigated the potential of laboratory- scale columns of immobilized micro-algae to disinfect effluents using thermo-tolerant coliforms (TTC) as a model system. Cells of a Chlorella species isolated from a waste stabilization pond complex in Northeast Brazil were immobilized in calcium alginate, packed into glass columns and incubated in contact with TTC suspensions for up to 24 hours. Five to six log removals of TTC were achieved in 6 hours and 11 log removals in 12 hours contact time. The results were similar under artificial light and shaded sunlight. However little or no TTC removal occurred in the light in columns of alginate beads without immobilized algae present or when the immobilized algae were incubated in the dark suggesting that the presence of both algae and light were necessary for TTC decay. There was a positive correlation between K(b) values for TTC and increasing pH in the effluent from the immobilized algal columns within the range pH 7.2 and 8.9. The potential of immobilized algal technology for wastewater disinfection may warrant further investigation.

Comparison of bitumen and cement immobilization of intermediate- and low-level radioactive waste

International Nuclear Information System (INIS)

Voss, J.W.

1979-01-01

This paper discusses a systems comparison of two available immobilization processes for intermediate- and low-level radioactive wastes -- bitumen and cement. This study examines a conceptual coprocessed UO 2 - PuO 2 fuel cycle. Radioactive wastes are generated at each stage of this fuel cycle. This study focuses on these transuranic (TRU) wastes generated at a conceptual Fuel Coprocessing Facility. In this report, these wastes are quantified, the immobilization systems conceptualized to process these wastes are presented, and a comparison of the systems is made

Antibodies immobilized on magnetic particles for RIA and IRMA of thyroid related hormones

International Nuclear Information System (INIS)

Wayan, R.S.; Djayusman, D.S.

1996-01-01

In Indonesia radioimmunoassay kits on the magnetic method of separation need to be imported and are very expensive. Local production of these kits would be economical. Different types of magnetic particles have been used for immobilizing antibodies for use in RIA of T 3 , T 4 , IRMA-TSH as well as neonatal IRMA-TSH. The particles studied here include magnetic cellulose (SCIPAC, U.K.), magnetite (Hungary), Silanized Iron Oxide (China) and Latex-M. Various parameters have been studied in order to optimize the antibody immobilization procedures as well as the assays based on these immunoadsorbents. The assays developed by us have been compared with those obtained with commercial kits from Amersham, NETRIA and DPC. The study done in this work includes immobilization of second antibodies for RIA of T 4 and immobilization of anti-TSH for IRMA-TSH. Among several different magnetic particles studied in this work, magnetite and silanized iron oxide were found to be satisfactory on account of the simplicity of immobilization, high binding capacity and the low non specific binding. A good assay performance in the case of RIA T 3 and T 4 was obtained using second antibodies immobilized magnetic particles. However, the quality of first antibodies is found to play an important role on the sensitivity and precision of the assay. Good correlation has been obtained with Amersham kit (y = 1.06x - 0.12 and r = 0.987). Assay performance of IRMA-TSH using in-house prepared anti-TSH immobilized magnetic particles is also found to be comparable with Amersham, NETRIA and DPC kits. (author). 4 refs, 6 figs, 1 tab

Immobilization and characterization of inulinase from Ulocladium

Indian Academy of Sciences (India)

Ulocladium atrum inulinase was immobilized on different composite membranes composed of chitosan/nonwoven fabrics. Km values of free and immobilized U. atrum inulinase on different composite membranes were calculated. The enzyme had optimum pH at 5.6 for free and immobilized U. atrum inulinase on polyester ...

A summary of methods for conditioning and immobilizing ion-exchange resins

International Nuclear Information System (INIS)

Speranzini, R.A.; Buckley, L.P.

1983-02-01

Ion-exchange resins are used in CANDU-PHW nuclear power stations to purify heavy water in the primary heat transport (PHT) and moderator systems. Two promising techniques for conditioning spent ion-exchange resins for disposal have been evaluated: direct immobilization and incineration combined with immobilization of the ash and scrubbed off-gases. When ion-exchange resins were immobilized directly, volumes of bitumen products were about 0.75 times the volumes of untreated resin, while the volumes of cement and polyester products were 2 to 3 times larger. While incinerating the resin is an extra processing step, much smaller volumes result from the latter option. Bitumen and glass product volumes were six and ten times smaller, respectively, than the volumes of untreated resin, while cement and polyester product volumes were about one-half the volume of untreated resin. Since the releases of Cs-136 by leaching were lowest for products made by immobilization in glass, PHT resins which have high concentrations of Cs-137 should be vitrified. Moderator resins which have high concentrations of C-14 should be incinerated and the ash and C-14-contaminated scrubbing solutions should be immobilized. By pretreating such resins with calcium chloride or carbon dioxide, the C-14 present on resin could be released at temperatures below the ignition temperature of the resin. The pretreatment technique reduces the amount of inactive carbon dioxide that must be scrubbed to trap the C-14. The releases of C-14 from immobilized barium hydroxide scrubbing solution were the same as releases from immobilized resin

Immobilization of immunoglobulin G in a highly oriented manner on a protein-A terminated multilayer system

Energy Technology Data Exchange (ETDEWEB)

Zengin, Adem [Department of Chemistry, Faculty of Art and Science, Gazi University, 06500 Besevler, Ankara (Turkey); Caykara, Tuncer, E-mail: caykara@gazi.edu.tr [Department of Chemistry, Faculty of Art and Science, Gazi University, 06500 Besevler, Ankara (Turkey)

2011-01-01

In this study, we have fabricated a multilayer system consisting of 3-glycidoxypropyldimethylmethoxysilane (GPDS), poly(dimethylsiloxane) bis 3-aminopropyl terminated (PDMS) and protein-A on a silicon wafer surface for oriented immobilization of immunoglobilin G (IgG). The multilayer system with a different component in each layer was characterized by ellipsometry, contact-angle goniometer, X-ray photoelectron spectroscopy (XPS) and atomic force microscopy (AFM) and fluorescence microscopy. The epoxy-terminated monolayer was formed by the chemisorption of GPDS molecules on the hydroxylated silicon surface. The PDMS film about 4.5 nm thick was produced on the GPDS-monolayer by the chemical reaction between the amine groups at the end of PDMS chain and the epoxy groups of GPDS molecules. By introducing the PDMS chains, the hydrophilic character of GPDS-monolayer decreased. Study of the time dependence of polymer grafting showed that the chemisorption of GPDS is fast, whereas at least 16 h is needed to generate the homogeneous PDMS layer. For immobilization of IgG molecules in a highly oriented manner, protein-A molecules were first chemically bound to an ultrathin ({approx}4.5 nm) PDMS reactive polymer layer and later used to capture IgG. It was shown that the existence of protein-A in the multilayer system has a strong influence on the binding properties of IgG not only in the efficiency of binding, but also in its specificity. In conclusion, the multilayer system with protein-A has the potential to be further developed into an efficient immunoassay protein chip.

Fabrication and properties of an immobilized P25TiO2-montmorillonite bilayer system for the synergistic photocatalytic–adsorption removal of methylene blue

International Nuclear Information System (INIS)

Ngoh, Y.S.; Nawi, M.A.

2016-01-01

Highlights: • P25TiO 2 and montmorillonite was integrated via an immobilized bilayer approach. • Synergistic dual photocatalytic–adsorptive removal of MB was observed. • Removal rate of MB was 4 times better than P25TiO 2 alone. • Excellent reusability with sustainable rate of removal of MB. • Treated water can be discharged directly without the need of a filtration system. - Abstract: A bilayer immobilized system consisting of a mesoporous montmorillonite (MT) as the sublayer and a porous P25TiO 2 toplayer was successfully fabricated on a glass plate. The MT sublayer was immobilized onto the glass plate by means of a glutaraldehyde (GLA) cross-linked poly (vinyl) alcohol (PVA) as the binder (MT-PVAB) while the top layer constituted of nano-sized TiO 2 bound by the ENR-PVC polymer blends (P-25TiO 2 ). The incorporation of MT-PVAB to P-25TiO 2 caused a reduction in the band gap energy while PLS emission spectra suggested higher separation rate for the photo-generated electron–hole pairs in the P-25TiO 2 /MT-PVAB/GP. The photocatalytic–adsorption removal experiments showed that the P-25TiO 2 /MT-PVAB/GP enhanced removal rate of MB by an average of 4 times as compared with the immobilized monolayer P-25TiO 2 on a glass plate (P-25TiO 2 /GP).

Immobilization of Mortierella vinacea cells by radiation polymerization

International Nuclear Information System (INIS)

Kumakura, M.; Kaetsu, I.

1983-01-01

Immobilization of Mortierella vinacea cells, which contain active α-galactosidase, by radiation polymerization at low temperatures was studied. The durability of the enzymatic activity of the immobilized cells obtained with hydrophilic monomers was affected by the concentrations of the cells and monomer in which optimum conditions were observed. The enzymatic activity of the immobilized cells obtained with hydrophilic monomers was compared to that of hydrophobic monomers. Michaelis constants of the immobilized cells varied with monomer concentration. The effect of addition of porous solid substances on the immobilization of the cells was studied

Development of a thiol-ene based screening platform for enzyme immobilization demonstrated using horseradish peroxidase

DEFF Research Database (Denmark)

Hoffmann, Christian; Pinelo, Manuel; Woodley, John

2017-01-01

Efficient immobilization of enzymes on support surfaces requires an exact match between the surface chemistry and the specific enzyme. A successful match would normally be identified through time consuming screening of conventional resins in multiple experiments testing individual immobilization...... strategies. In this study we present a versatile strategy that largely expands the number of possible surface functionalities for enzyme immobilization in a single, generic platform. The combination of many individual surface chemistries and thus immobilization methods in one modular system permits faster...... functionalization by thiol-ene chemistry (TEC) resulted in the formation of a functional monolayer in each well, whereas, polymer surface grafts were introduced through surface chain transfer free radical polymerization (SCT-FRP). Enzyme immobilization on the modified surfaces was evaluated by using a rhodamine...

Production of Galactooligosaccharides Using β-Galactosidase Immobilized on Chitosan-Coated Magnetic Nanoparticles with Tris(hydroxymethylphosphine as an Optional Coupling Agent

Directory of Open Access Journals (Sweden)

Su-Ching Chen

2015-06-01

Full Text Available β-Galactosidase was immobilized on chitosan-coated magnetic Fe3O4 nanoparticles and was used to produce galactooligosaccharides (GOS from lactose. Immobilized enzyme was prepared with or without the coupling agent, tris(hydroxymethylphosphine (THP. The two immobilized systems and the free enzyme achieved their maximum activity at pH 6.0 with an optimal temperature of 50 °C. The immobilized enzymes showed higher activities at a wider range of temperatures and pH. Furthermore, the immobilized enzyme coupled with THP showed higher thermal stability than that without THP. However, activity retention of batchwise reactions was similar for both immobilized systems. All the three enzyme systems produced GOS compound with similar concentration profiles, with a maximum GOS yield of 50.5% from 36% (w·v−1 lactose on a dry weight basis. The chitosan-coated magnetic Fe3O4 nanoparticles can be regenerated using a desorption/re-adsorption process described in this study.

Packaging design criteria (onsite) project W-520 immobilized low-activity waste transportation system

International Nuclear Information System (INIS)

BOEHNKE, W.M.

2001-01-01

A plan is currently in place to process the high-level radioactive wastes that resulted from uranium and plutonium recovery operations from Spent Nuclear Fuel at the Hanford Site, Richland, Washington. Currently, millions of gallons of high-level radioactive waste in the form of liquids, sludges, and saltcake are stored in many large underground tanks onsite. This waste will be processed and separated into high-level and low-activity fractions. Both fractions will then be vitrified (i.e., blended with molten borosilicate glass) in order to encapsulate the toxic radionuclides. The immobilized low-activity waste (ILAW) glass will be poured into LAW canisters, allowed to cool and harden to solid form, sealed by welding, and then transported to a double-lined trench in the 200 East Area for permanent disposal. This document presents the packaging design criteria (PDC) for an onsite LAW transportation system, which includes the ILAW canister, ILAW package, and transport vehicle and defines normal and accident conditions. This PDC provides the basis for the ILAW onsite transportation system design and fabrication and establishes the transportation safety criteria that the design will be evaluated against in the Package Specific Safety Document (PSSD). It provides the criteria for the ILAW canister, cask and transport vehicles and defines normal and accident conditions. The LAW transportation system is designed to transport stabilized waste from the vitrification facility to the ILAW disposal facility developed by Project W-520. All ILAW transport will take place within the 200 East Area (all within the Hanford Site)

Investigations of titamium and zirconium hydrides to determine suitability of recoverable tritium immobilization for the Pickering tritium removal system

International Nuclear Information System (INIS)

Noga, J.O.

1981-11-01

A tritium removal system will be constructed at Pickering Nuclear Generating station to reduce the adverse effects of this radioactive hydrogen isotope. This report summarizes various properties of titanium and zirconium sponge hydrides which have been selected as suitable candidates for tritium product immobilization. Equilibrium pressure-composition-temperature data indicates that both materials behave suitably to provide a safe, solid form of tritium storage. Titanium tritide is recommended as the best choice due to higher dissociation pressures which can be achieved at equivalent temperatures when compared to zirconium tritide. Higher dissociation pressures would result in faster and more efficient recovery of tritium gas from the immobilized state. It is evident from the stability of these compounds that their utilization as tritides will greatly enhance the integrity of tritium storage

Immobilization of lipases in PSS/PEO blends and applications in esters synthesis

International Nuclear Information System (INIS)

Vecchia, Roberto D.; Nascimento, Maria G.; Soldi, Valdir

2001-01-01

Various lipases were immobilized in PSS/PEO blends and used as bio catalysts in the esterification reaction of lauric acid with n-pentanol, in hexane as a solvent for 24 h at 35 deg C. The best results in the ester conversion, were obtained by using lipase from Rhryzopus oryzae immobilized in PSS/PEO 80:20 blend. The data are in agreement with DSC and TGA values, which showed that these systems (blend/lipase) were very stable with low mass loss. No product was obtained by using lipase FAP-15 immobilized in PSS film , showing the strong influence of the polymer on enzyme activity. (author)

Silica-Immobilized Enzyme Reactors; Application to Cholinesterase-Inhibition Studies

National Research Council Canada - National Science Library

Luckarift, Heather R; Johnson, Glenn R; Spain, Jim C

2006-01-01

...) using silica-encapsulated equine butyrycholinestearse (BuChE) as a model system. Peptide-mediated silica formation was used to encapsulate BuChE, directly immobilizing the enzyme within a commercial pre-packed column...

Enzymatic removal of phenol and p-chlorophenol in enzyme reactor: Horseradish peroxidase immobilized on magnetic beads

International Nuclear Information System (INIS)

Bayramoglu, Guelay; Arica, M. Yakup

2008-01-01

Horseradish peroxidase was immobilized on the magnetic poly(glycidylmethacrylate-co-methylmethacrylate) (poly(GMA-MMA)), via covalent bonding and used for the treatment of phenolic wastewater in continuous systems. For this purposes, horseradish peroxidase (HRP) was covalently immobilized onto magnetic poly(GMA-MMA) beds using glutaraldehyde (GA) as a coupling agent. The maximum HRP immobilization capacity of the magnetic poly(GMA-MMA)-GA beads was 3.35 mg g -1 . The immobilized HRP retained 79% of the activity of the free HRP used for immobilization. The immobilized HRP was used for the removal of phenol and p-chlorophenol via polymerization of dissolved phenols in the presence of hydrogen peroxide (H 2 O 2 ). The effect of pH and temperature on the phenol oxidation rate was investigated. The results were compared with the free HRP, which showed that the optimum pH value for the immobilized HRP is similar to that for the free HRP. The optimum pH value for free and immobilized HRP was observed at pH 7.0. The optimum temperature for phenols oxidation with immobilized HRP was between 25 and 35 deg. C and the immobilized HRP has more resistance to temperature inactivation than that of the free form. Finally, the immobilized HRP was operated in a magnetically stabilized fluidized bed reactor, and phenols were successfully removed in the enzyme reactor

Ethanol fermentation of molasses by Saccharomyces cerevisiae cells immobilized onto sugar beet pulp

Directory of Open Access Journals (Sweden)

Vučurović Vesna M.

2012-01-01

Full Text Available Natural adhesion of Saccharomyces cerevisiae onto sugar beet pulp (SBP is a very simple and cheap immobilization method for retaining high cells density in the ethanol fermentation system. In the present study, yeast cells were immobilized by adhesion onto SBP suspended in the synthetic culture media under different conditions such as: glucose concentration (100, 120 and 150 g/l, inoculum concentration (5, 10 and 15 g/l dry mass and temperature (25, 30, 35 and 40°C. In order to estimate the optimal immobilization conditions the yeast cells retention (R, after each immobilization experiment was analyzed. The highest R value of 0.486 g dry mass yeast /g dry mass SBP was obtained at 30°C, glucose concentration of 150 g/l, and inoculum concentration of 15 g/l. The yeast immobilized under these conditions was used for ethanol fermentation of sugar beet molasses containing 150.2 g/l of reducing sugar. Efficient ethanol fermentation (ethanol concentration of 70.57 g/l, fermentation efficiency 93.98% of sugar beet molasses was achieved using S. cerevisiae immobilized by natural adhesion on SBP. [Projekat Ministarstva nauke Republike Srbije, br. TR-31002

Reversible thermal denaturation of immobilized rhodanese

International Nuclear Information System (INIS)

Horowitz, P.; Bowman, S.

1987-01-01

For the first time, the enzyme rhodanese had been refolded after thermal denaturation. This was previously not possible because of the strong tendency for the soluble enzyme to aggregate at temperatures above 37 degrees C. The present work used rhodanese that was covalently coupled to a solid support under conditions that were found to preserve enzyme activity. Rhodanese was immobilized using an N-hydroxymalonimidyl derivative of Sepharose containing a 6-carbon spacer. The number of immobilized competent active sites was measured by using [ 35 S]SO 3 (2-) to form an active site persulfide that is the obligatory catalytic intermediate. Soluble enzyme was irreversibly inactivated in 10 min at 52 degrees C. The immobilized enzyme regained at least 30% of its original activity even after boiling for 20 min. The immobilized enzyme had a Km and Vmax that were each approximately 3 times higher than the corresponding values for the native enzyme. After preincubation at high temperatures, progress curves for the immobilized enzyme showed induction periods of up to 5 min before attaining apparently linear steady states. The pH dependence of the activity was the same for both the soluble and the immobilized enzyme. These results indicate significant stabilization of rhodanese after immobilization, and instabilities caused by adventitious solution components are not the sole reasons for irreversibility of thermal denaturation seen with the soluble enzyme. The results are consistent with models for rhodanese that invoke protein association as a major cause of inactivation of the enzyme. Furthermore, the induction period in the progress curves is consistent with studies which show that rhodanese refolding proceeds through intermediate states

Supplemental Immobilization of Hanford Low-Activity Waste: Cast Stone Screening Tests

Energy Technology Data Exchange (ETDEWEB)

Westsik, Joseph H. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Piepel, Gregory F. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Lindberg, Michael J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Heasler, Patrick G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Mercier, Theresa M. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Russell, Renee L. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Cozzi, Alex [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Daniel, William E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Eibling, Russell E. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Hansen, E. K. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Reigel, Marissa M. [Savannah River Site (SRS), Aiken, SC (United States). Savannah River National Lab. (SRNL); Swanberg, David J. [Washington River Protection Solutions (WRPS), Aiken, SC (United States)

2013-09-30

More than 56 million gallons of radioactive and hazardous waste are stored in 177 underground storage tanks at the U.S. Department of Energy’s (DOE’s) Hanford Site in southeastern Washington State. The Hanford Tank Waste Treatment and Immobilization Plant (WTP) is being constructed to treat the wastes and immobilize them in a glass waste form. The WTP includes a pretreatment facility to separate the wastes into a small volume of high-level waste (HLW) containing most of the radioactivity and a larger volume of low-activity waste (LAW) containing most of the nonradioactive chemicals. The HLW will be converted to glass in the HLW vitrification facility for ultimate disposal at an offsite federal repository. At least a portion (~35%) of the LAW will be converted to glass in the LAW vitrification facility and will be disposed of onsite at the Integrated Disposal Facility (IDF). The pretreatment and HLW vitrification facilities will have the capacity to treat and immobilize the wastes destined for each facility. However, a second LAW immobilization facility will be needed for the expected volume of LAW requiring immobilization. A cementitious waste form known as Cast Stone is being considered to provide the required additional LAW immobilization capacity. The Cast Stone waste form must be acceptable for disposal in the IDF. The Cast Stone waste form and immobilization process must be tested to demonstrate that the final Cast Stone waste form can comply with the waste acceptance criteria for the disposal facility and that the immobilization processes can be controlled to consistently provide an acceptable waste form product. Further, the waste form must be tested to provide the technical basis for understanding the long-term performance of the waste form in the disposal environment. These waste form performance data are needed to support risk assessment and performance assessment (PA) analyses of the long-term environmental impact of the waste disposal in the IDF

Properties of immobilized papain by radiation polymerization

International Nuclear Information System (INIS)

Kumakura, Minoru; Kaetsu, Isao

1984-01-01

Papain was immobilized by the radiation polymerization of various monomers at low temperatures and the effects of the polymer matrix on the enzyme activity and thermal stability of the immobilized enzymes were studied. The activity of the immobilized enzymes prepared from monofunctional (acrylate and methacrylate) monomers was higher than that from bifunctional (bismethacrylate) monomers and that from polyoxyethylene dimethacrylate monomers increased with an increase in the number of oxyethylene units. The thermal stability of the immobilized enzymes prepared from hydrophilic monomers was higher than that from hydrophobic monomers and increased markedly with increasing monomer concentration. (author)

Synthesis of naringin 6"-ricinoleate using immobilized lipase

Directory of Open Access Journals (Sweden)

Almeida Verônica M

2012-05-01

Full Text Available Abstract Background Naringin is an important flavanone with several biological activities, including antioxidant action. However, this compound shows low solubility in lipophilic preparations, such as is used in the cosmetic and food industries. One way to solve this problem is to add fatty acids to the flavonoid sugar unit using immobilized lipase. However, there is limited research regarding hydroxylation of unsaturated fatty acids as an answer to the low solubility challenge. In this work, we describe the reaction of naringin with castor oil containing ricinoleic acid, castor oil's major fatty acid component, using immobilized lipase from Candida antarctica. Analysis of the 1H and 13 C NMR (1D and 2D spectra and literature comparison were used to characterise the obtained acyl derivative. Results After allowing the reaction to continue for 120 hours (in acetone media, 50°C, the major product obtained was naringin 6″-ricinoleate. In this reaction, either castor oil or pure ricinoleic acid was used as the acylating agent, providing a 33% or 24% yield, respectively. The chemical structure of naringin 6″-ricinoleate was determined using NMR analysis, including bidimensional (2D experiments. Conclusion Using immobilized lipase from C. antarctica, the best conversion reaction was observed using castor oil containing ricinoleic acid as the acylating agent rather than an isolated fatty acid. Graphical abstract

Enzyme Technology of Peroxidases: Immobilization, Chemical and Genetic Modification

Science.gov (United States)

Longoria, Adriana; Tinoco, Raunel; Torres, Eduardo

An overview of enzyme technology applied to peroxidases is made. Immobilization on organic, inorganic, and hybrid supports; chemical modification of amino acids and heme group; and genetic modification by site-directed and random mutagenesis are included. Different strategies that were carried out to improve peroxidase performance in terms of stability, selectivity, and catalytic activity are analyzed. Immobilization of peroxidases on inorganic and organic materials enhances the tolerance of peroxidases toward the conditions normally found in many industrial processes, such as the presence of an organic solvent and high temperature. In addition, it is shown that immobilization helps to increase the Total Turnover Number at levels high enough to justify the use of a peroxidase-based biocatalyst in a synthesis process. Chemical modification of peroxidases produces modified enzymes with higher thermostability and wider substrate variability. Finally, through mutagenesis approaches, it is possible to produce modified peroxidases capable of oxidizing nonnatural substrates with high catalytic activity and affinity.

Ethanol production from concentrated food waste hydrolysates with yeast cells immobilized on corn stalk

Energy Technology Data Exchange (ETDEWEB)

Yan, Shoubao [Huainan Normal Univ., Anhui (China). School of Life Science; Chen, Xiangsong; Wu, Jingyong; Wang, Pingchao [Chinese Academy of Sciences, Hefei (China). Key Lab. of Ion Beam Bio-engineering of Inst. of Plasma Physics

2012-05-15

The aim of the present study was to examine ethanol production from concentrated food waste hydrolysates using whole cells of S. cerevisiae immobilized on corn stalks. In order to improve cell immobilization efficiency, biological modification of the carrier was carried out by cellulase hydrolysis. The results show that proper modification of the carrier with cellulase hydrolysis was suitable for cell immobilization. The mechanism proposed, cellulase hydrolysis, not only increased the immobilized cell concentration, but also disrupted the sleek surface to become rough and porous, which enhanced ethanol production. In batch fermentation with an initial reducing sugar concentration of 202.64 {+-} 1.86 g/l, an optimal ethanol concentration of 87.91 {+-} 1.98 g/l was obtained using a modified corn stalk-immobilized cell system. The ethanol concentration produced by the immobilized cells was 6.9% higher than that produced by the free cells. Ethanol production in the 14th cycle repeated batch fermentation demonstrated the enhanced stability of the immobilized yeast cells. Under continuous fermentation in an immobilized cell reactor, the maximum ethanol concentration of 84.85 g/l, and the highest ethanol yield of 0.43 g/g (of reducing sugar) were achieved at hydraulic retention time (HRT) of 3.10 h, whereas the maximum volumetric ethanol productivity of 43.54 g/l/h was observed at a HRT of 1.55 h. (orig.)

Preparation of Laccase Immobilized Cryogels and Usage for Decolorization

Directory of Open Access Journals (Sweden)

Murat Uygun

2013-01-01

Full Text Available Poly(methyl methacrylate-co-glycidyl methacrylate (poly(MMA-co-GMA cryogels were synthesized by radical cryopolymerization technique. Then, laccase enzyme was covalently attached to the cryogel and characterized by using swelling studies and SEM and EDX analyses. Kinetic properties and optimum conditions of the immobilized and free laccase were studied and it was found that of the immobilized laccase was lower than that of free laccase. of the immobilized laccase was increased upon immobilization. Optimum pH was found to be 4.0 for each type of laccase, while optimum temperature was shifted to the warmer region after the immobilization. It was also found that thermal stability of the immobilized laccase was higher than that of free laccase. Immobilized laccase could be used for 10 times successive reuse with no significant decrease in its activity. Also, these laccase immobilized cryogels were successfully used for the decolorization of seven different dyes.

A comparison between four immobilization systems for pelvic radiation therapy using CBCT and paired kilovoltage portals based image-guided radiotherapy

Directory of Open Access Journals (Sweden)

Gagan Saini

2014-01-01

Conclusions: SM was low for all the four immobilization systems studied. There is no added benefit of using a VC with 6-clamped TM for pelvic RT. Use of a VC is recommended with 4-clamped TM to improve overall reproducibility. 6-clamped TM helps keep the errors low.

Plutonium immobilization in glass and ceramics

Energy Technology Data Exchange (ETDEWEB)

Knecht, D.A. [Lockheed Martin Idaho Technologies, Idaho Falls (United States); Murphy, W.M. [Southwest Research Institute, San Antonio, TX (United States)

1996-05-01

The Materials Research Society Nineteenth Annual Symposium on the Scientific Basis for Nuclear Waste Management was held in Boston on November 27 to December 1, 1995. Over 150 papers were presented at the Symposium dealing with all aspects of nuclear waste management and disposal. Fourteen oral sessions and on poster session included a Plenary session on surplus plutonium dispositioning and waste forms. The proceedings, to be published in April, 1996, will provide a highly respected, referred compilation of the state of scientific development in the field of nuclear waste management. This paper provides a brief overview of the selected Symposium papers that are applicable to plutonium immobilization and plutonium waste form performance. Waste forms that were described at the Symposium cover most of the candidate Pu immobilization options under consideration, including borosilicate glass with a melting temperature of 1150 {degrees}C, a higher temperature (1450 {degrees}C) lanthanide glass, single phase ceramics, multi-phase ceramics, and multi-phase crystal-glass composites (glass-ceramics or slags). These Symposium papers selected for this overview provide the current status of the technology in these areas and give references to the relevant literature.

Plutonium immobilization in glass and ceramics

International Nuclear Information System (INIS)

Knecht, D.A.; Murphy, W.M.

1996-01-01

The Materials Research Society Nineteenth Annual Symposium on the Scientific Basis for Nuclear Waste Management was held in Boston on November 27 to December 1, 1995. Over 150 papers were presented at the Symposium dealing with all aspects of nuclear waste management and disposal. Fourteen oral sessions and on poster session included a Plenary session on surplus plutonium dispositioning and waste forms. The proceedings, to be published in April, 1996, will provide a highly respected, referred compilation of the state of scientific development in the field of nuclear waste management. This paper provides a brief overview of the selected Symposium papers that are applicable to plutonium immobilization and plutonium waste form performance. Waste forms that were described at the Symposium cover most of the candidate Pu immobilization options under consideration, including borosilicate glass with a melting temperature of 1150 degrees C, a higher temperature (1450 degrees C) lanthanide glass, single phase ceramics, multi-phase ceramics, and multi-phase crystal-glass composites (glass-ceramics or slags). These Symposium papers selected for this overview provide the current status of the technology in these areas and give references to the relevant literature

Comparative study on antibody immobilization strategies for efficient circulating tumor cell capture.

Science.gov (United States)

Ates, Hatice Ceren; Ozgur, Ebru; Kulah, Haluk

2018-03-23

Methods for isolation and quantification of circulating tumor cells (CTCs) are attracting more attention every day, as the data for their unprecedented clinical utility continue to grow. However, the challenge is that CTCs are extremely rare (as low as 1 in a billion of blood cells) and a highly sensitive and specific technology is required to isolate CTCs from blood cells. Methods utilizing microfluidic systems for immunoaffinity-based CTC capture are preferred, especially when purity is the prime requirement. However, antibody immobilization strategy significantly affects the efficiency of such systems. In this study, two covalent and two bioaffinity antibody immobilization methods were assessed with respect to their CTC capture efficiency and selectivity, using an anti-epithelial cell adhesion molecule (EpCAM) as the capture antibody. Surface functionalization was realized on plain SiO 2 surfaces, as well as in microfluidic channels. Surfaces functionalized with different antibody immobilization methods are physically and chemically characterized at each step of functionalization. MCF-7 breast cancer and CCRF-CEM acute lymphoblastic leukemia cell lines were used as EpCAM positive and negative cell models, respectively, to assess CTC capture efficiency and selectivity. Comparisons reveal that bioaffinity based antibody immobilization involving streptavidin attachment with glutaraldehyde linker gave the highest cell capture efficiency. On the other hand, a covalent antibody immobilization method involving direct antibody binding by N-(3-dimethylaminopropyl)-N'-ethylcarbodiimide hydrochloride (EDC)-N-hydroxysuccinimide (NHS) reaction was found to be more time and cost efficient with a similar cell capture efficiency. All methods provided very high selectivity for CTCs with EpCAM expression. It was also demonstrated that antibody immobilization via EDC-NHS reaction in a microfluidic channel leads to high capture efficiency and selectivity.

Fabrication and properties of an immobilized P25TiO{sub 2}-montmorillonite bilayer system for the synergistic photocatalytic–adsorption removal of methylene blue

Energy Technology Data Exchange (ETDEWEB)

Ngoh, Y.S.; Nawi, M.A., E-mail: masri@usm.my

2016-04-15

Highlights: • P25TiO{sub 2} and montmorillonite was integrated via an immobilized bilayer approach. • Synergistic dual photocatalytic–adsorptive removal of MB was observed. • Removal rate of MB was 4 times better than P25TiO{sub 2} alone. • Excellent reusability with sustainable rate of removal of MB. • Treated water can be discharged directly without the need of a filtration system. - Abstract: A bilayer immobilized system consisting of a mesoporous montmorillonite (MT) as the sublayer and a porous P25TiO{sub 2} toplayer was successfully fabricated on a glass plate. The MT sublayer was immobilized onto the glass plate by means of a glutaraldehyde (GLA) cross-linked poly (vinyl) alcohol (PVA) as the binder (MT-PVAB) while the top layer constituted of nano-sized TiO{sub 2} bound by the ENR-PVC polymer blends (P-25TiO{sub 2}). The incorporation of MT-PVAB to P-25TiO{sub 2} caused a reduction in the band gap energy while PLS emission spectra suggested higher separation rate for the photo-generated electron–hole pairs in the P-25TiO{sub 2}/MT-PVAB/GP. The photocatalytic–adsorption removal experiments showed that the P-25TiO{sub 2}/MT-PVAB/GP enhanced removal rate of MB by an average of 4 times as compared with the immobilized monolayer P-25TiO{sub 2} on a glass plate (P-25TiO{sub 2}/GP).

Immobilization of chlorine dioxide modified cells for uranium absorption

International Nuclear Information System (INIS)

He, Shengbin; Ruan, Binbiao; Zheng, Yueping; Zhou, Xiaobin; Xu, Xiaoping

2014-01-01

There has been a trend towards the use of microorganisms to recover metals from industrial wastewater, for which various methods have been reported to be used to improve microorganism adsorption characteristics such as absorption capacity, tolerance and reusability. In present study, chlorine dioxide(ClO 2 ), a high-efficiency, low toxicity and environment-benign disinfectant, was first reported to be used for microorganism surface modification. The chlorine dioxide modified cells demonstrated a 10.1% higher uranium adsorption capacity than control ones. FTIR analysis indicated that several cell surface groups are involved in the uranium adsorption and cell surface modification. The modified cells were further immobilized on a carboxymethylcellulose (CMC) matrix to improve their reusability. The cell-immobilized adsorbent could be employed either in a high concentration system to move vast UO 2 2+ ions or in a low concentration system to purify UO 2 2+ contaminated water thoroughly, and could be repeatedly used in multiple adsorption-desorption cycles with about 90% adsorption capacity maintained after seven cycles. - Highlights: • Chlorine dioxide was first reported to be used for microorganism surface modification. • The chlorine dioxide modified cells demonstrated a 10.1% higher uranium adsorption capacity than control ones. • The chlorine dioxide modified cells were further immobilized by carboxymethylcellulose to improve their reusability

Novel immobilization process of a thermophilic catalase: efficient purification by heat treatment and subsequent immobilization at high temperature.

Science.gov (United States)

Xu, Juan; Luo, Hui; López, Claudia; Xiao, Jing; Chang, Yanhong

2015-10-01

The main goal of the present work is to investigate a novel process of purification and immobilization of a thermophilic catalase at high temperatures. The catalase, originated from Bacillus sp., was overexpressed in a recombinant Escherichia coli BL21(DE3)/pET28-CATHis and efficiently purified by heat treatment, achieving a threefold purification. The purified catalase was then immobilized onto an epoxy support at different temperatures (25, 40, and 55 °C). The immobilizate obtained at higher temperatures reached its maximum activity in a shorter time than that obtained at lower temperatures. Furthermore, immobilization at higher temperatures required a lower ionic strength than immobilization at lower temperatures. The characteristics of immobilized enzymes prepared at different temperatures were investigated. The high-temperature immobilizate (55 °C) showed the highest thermal stability, followed by the 40 °C immobilizate. And the high-temperature immobilizate (55 °C) had slightly higher operational stability than the 25 °C immobilizate. All of the immobilized catalase preparations showed higher stability than the free enzyme at alkaline pH 10.0, while the alkali resistance of the 25 °C immobilizate was slightly better than that of the 40 and 55 °C immobilizates.

A study of ethanol production of yeast cells immobilized with polymer carrier produced by radiation polymerization

International Nuclear Information System (INIS)

Lu Zhaoxin; Fujimura, Takashi

1993-01-01

Polymer carriers, poly(hydroxyethyl acrylate(HEA)-methoxy polyethylene glycol methylacrylate (M-23G)) and poly(hydroxyethyl acrylate(HEA)-glycidyl methylacrylate (GMA)) used for the immobilization of yeast cells were prepared by radiation polymerization at low temperature. Yeast cells were immobilized through adhesion and multiplication of yeast cells. The ethanol productivity of immobilized yeast cells with these carriers was related to the monomer composition of polymers and the optimum monomer composition was 20%:10% in poly(HEA-M-23G) and 17%:6% in poly(HEA-GMA). In this case, the ethanol productivity of immobilized yeast cells was about 4 times that of cells in free system. The relationship between the activity of immobilized yeast cells and the water content of the polymer carrier were also discussed. (author)

High production of D-tagatose, a potential sugar substitute, using immobilized L-arabinose isomerase.

Science.gov (United States)

Kim, P; Yoon, S H; Roh, H J; Choi, J H

2001-01-01

An L-arabinose isomerase of Escherichia coli was immobilized using covalent binding to agarose to produce D-tagatose, a bulking sweetener that can be economically used as a sugar substitute. The immobilized L-arabinose isomerase stably produced an average of 7.5 g-tagatose/L.day for 7 days with a productivity exceeding that of the free enzyme (0.47 vs 0.30 mg/U.day). Using a scaled-up immobilized enzyme system, 99.9 g-tagatose/L was produced from galactose with 20% equilibrium in 48 h. The process was repeated two more times with production of 104.1 and 103.5 g-tagatose/L. D-Tagatose production using an immobilized L-arabinose isomerase has a high potential for commercial application.

Glucose Oxidase Immobilization on TMAH-Modified Bentonite

Directory of Open Access Journals (Sweden)

Ruth Chrisnasari

2015-03-01

Full Text Available The influence of bentonite modification by tetramethyl ammonium hydroxide (TMAH on its capability to immobilize glucose oxidase (GOX was studied. Modification of bentonite was conducted by the adding of 0-5% (v/v TMAH. The observed results show that the different concentrations of TMAH affect the percentage of immobilized enzyme. The results of this study show that the best concentration of TMAH is 5% (v/v which can immobilize up to 84.71% of GOX. X-ray diffraction (XRD and Fourier Transforms Infrared Spectroscopy (FTIR studies have been carried out to observe the structural changes in bentonite due to TMAH modification. The obtained immobilized GOX show the optimum catalytic activity on reaction temperature of 40-50 °C and pH of 7. The immobilized GOX kinetics at the optimum conditions determined the Km and Vmax value to be 4.96x10-2 mM and 4.99x10-3 mM.min-1 respectively. In addition, the immobilized GOX on TMAH-modified bentonite is stable enough so it could be re-used six times before its activity decreased by 39.44%.

Biotechnological production of vanillin using immobilized enzymes.

Science.gov (United States)

Furuya, Toshiki; Kuroiwa, Mari; Kino, Kuniki

2017-02-10

Vanillin is an important and popular plant flavor, but the amount of this compound available from plant sources is very limited. Biotechnological methods have high potential for vanillin production as an alternative to extraction from plant sources. Here, we report a new approach using immobilized enzymes for the production of vanillin. The recently discovered oxygenase Cso2 has coenzyme-independent catalytic activity for the conversion of isoeugenol and 4-vinylguaiacol to vanillin. Immobilization of Cso2 on Sepabeads EC-EA anion-exchange carrier conferred enhanced operational stability enabling repetitive use. This immobilized Cso2 catalyst allowed 6.8mg yield of vanillin from isoeugenol through ten reaction cycles at a 1mL scale. The coenzyme-independent decarboxylase Fdc, which has catalytic activity for the conversion of ferulic acid to 4-vinylguaiacol, was also immobilized on Sepabeads EC-EA. We demonstrated that the immobilized Fdc and Cso2 enabled the cascade synthesis of vanillin from ferulic acid via 4-vinylguaiacol with repetitive use of the catalysts. This study is the first example of biotechnological production of vanillin using immobilized enzymes, a process that provides new possibilities for vanillin production. Copyright © 2016 Elsevier B.V. All rights reserved.

Antimicrobial activity of immobilized lactoferrin and lactoferricin.

Science.gov (United States)

Chen, Renxun; Cole, Nerida; Dutta, Debarun; Kumar, Naresh; Willcox, Mark D P

2017-11-01

Lactoferrin and lactoferricin were immobilized on glass surfaces via two linkers, 4-azidobenzoic acid (ABA) or 4-fluoro-3-nitrophenyl azide (FNA). The resulting surfaces were characterized by X-ray photoelectron spectroscopy (XPS) and contact angle measurements. The antimicrobial activity of the surfaces was determined using Pseudomonas aeruginosa and Staphylococcus aureus strains by fluorescence microscopy. Lactoferrin and lactoferricin immobilization was confirmed by XPS showing significant increases (p lactoferricin immobilized on glass significantly (p lactoferricin were successfully immobilized on glass surfaces and showed promising antimicrobial activity against pathogenic bacteria. © 2016 Wiley Periodicals, Inc. J Biomed Mater Res Part B: Appl Biomater, 105B: 2612-2617, 2017. © 2016 Wiley Periodicals, Inc.

Potential Applications of Carbohydrases Immobilization in the Food Industry

Science.gov (United States)

Contesini, Fabiano Jares; de Alencar Figueira, Joelise; Kawaguti, Haroldo Yukio; de Barros Fernandes, Pedro Carlos; de Oliveira Carvalho, Patrícia; Nascimento, Maria da Graça; Sato, Hélia Harumi

2013-01-01

Carbohydrases find a wide application in industrial processes and products, mainly in the food industry. With these enzymes, it is possible to obtain different types of sugar syrups (viz. glucose, fructose and inverted sugar syrups), prebiotics (viz. galactooligossacharides and fructooligossacharides) and isomaltulose, which is an interesting sweetener substitute for sucrose to improve the sensory properties of juices and wines and to reduce lactose in milk. The most important carbohydrases to accomplish these goals are of microbial origin and include amylases (α-amylases and glucoamylases), invertases, inulinases, galactosidases, glucosidases, fructosyltransferases, pectinases and glucosyltransferases. Yet, for all these processes to be cost-effective for industrial application, a very efficient, simple and cheap immobilization technique is required. Immobilization techniques can involve adsorption, entrapment or covalent bonding of the enzyme into an insoluble support, or carrier-free methods, usually based on the formation of cross-linked enzyme aggregates (CLEAs). They include a broad variety of supports, such as magnetic materials, gums, gels, synthetic polymers and ionic resins. All these techniques present advantages and disadvantages and several parameters must be considered. In this work, the most recent and important studies on the immobilization of carbohydrases with potential application in the food industry are reviewed. PMID:23344046

Effect of Cell-to-matrix Ratio in Polyvinyl Alcohol Immobilized Pure and Mixed Cultures on Atrazine Degradation

International Nuclear Information System (INIS)

Siripattanakul, Sumana; Wirojanagud, Wanpen; McEvoy, John; Khan, Eakalak

2008-01-01

Atrazine biodegradation by immobilized pure and mixed cultures was examined. A pure atrazine-degrading culture, Agrobacterium radiobacter J14a (J14a), and a mixed culture (MC), isolated from an atrazine-contaminated crop field, were immobilized using phosphorylated-polyvinyl alcohol (PPVA). An existing cell immobilization procedure was modified to enhance PPVA matrix stability. The results showed that the matrices remained mechanically and chemically stable after shaking with glass beads over 15 days under various salt solutions and pH values. The immobilization process had a slight effect on cell viability. With the aid of scanning electron microscopy, a suitable microstructure of PPVA matrices for cell entrapment was observed. There were two porous layers of spherical gel matrices, the outside having an encapsulation property and the inside containing numerous pores for bacteria to occupy. J14a and MC were immobilized at three cell-to-matrix ratios of 3.5, 6.7, and 20 mg dry cells/mL matrix. The atrazine biodegradation tests were conducted in an aerobic batch system, which was inoculated with cells at 2,000 mg/L. The tests were also conducted using free (non-immobilized) J14a and MC for comparative purpose. The cell-to-matrix ratio of 3.5 mg/mL provided the highest atrazine removal efficiency of 40-50% in 120 h for both J14a and MC. The free cell systems, for both cultures, presented much lower atrazine removal efficiencies compared to the immobilized cell systems at the same level of inoculation

Study on the immobilization of alpha-amylase by radiation-induced polymerization at low-temperature, (3)

International Nuclear Information System (INIS)

Yoshida, Masaru; Kumakura, Minoru; Kaetsu, Isao

1975-07-01

The immobilization of α-amylase in high concentration (50-200 mg) by radiation induced polymerization at low temperature, with HEMA has been studied. A feature of the high concentration α-amylase system is phase separation of the mixed solution prior to polymerization, markedly at HEMA concentrations above 50%. Useful immobilization is possible, however, by irradiation of the suspended composition at -196 0 C, which is obtained by shaking the phase-separated system. At temperatures below 0 0 C, the immobilization is possible, but not above this because of the phase separation. The polymerizability of HEMA changes abruptly at 0 0 C. The largest polymerization rate is obtained at -24 0 C, possibly due to phase change by crystallization of water of the buffer solution at 0 0 C. Activity of the immobilized high-concentration α-amylase is as high as 80-85% being somewhat higher than that in the low-concentration case. (auth.)

Waste immobilization process development at the Savannah River Plant

International Nuclear Information System (INIS)

Charlesworth, D.L.

1986-01-01

Processes to immobilize various wasteforms, including waste salt solution, transuranic waste, and low-level incinerator ash, are being developed. Wasteform characteristics, process and equipment details, and results from field/pilot tests and mathematical modeling studies are discussed

Design requirements document for project W-520, immobilized low-activity waste disposal

International Nuclear Information System (INIS)

Ashworth, S.C.

1998-01-01

This design requirements document (DRD) identifies the functions that must be performed to accept, handle, and dispose of the immobilized low-activity waste (ILAW) produced by the Tank Waste Remediation System (TWRS) private treatment contractors and close the facility. It identifies the requirements that are associated with those functions and that must be met. The functional and performance requirements in this document provide the basis for the conceptual design of the Tank Waste Remediation System Immobilized Low-Activity Waste disposal facility project (W-520) and provides traceability from the program-level requirements to the project design activity

Design requirements document for project W-520, immobilized low-activity waste disposal

Energy Technology Data Exchange (ETDEWEB)

Ashworth, S.C.

1998-08-06

This design requirements document (DRD) identifies the functions that must be performed to accept, handle, and dispose of the immobilized low-activity waste (ILAW) produced by the Tank Waste Remediation System (TWRS) private treatment contractors and close the facility. It identifies the requirements that are associated with those functions and that must be met. The functional and performance requirements in this document provide the basis for the conceptual design of the Tank Waste Remediation System Immobilized Low-Activity Waste disposal facility project (W-520) and provides traceability from the program-level requirements to the project design activity.

Immobilization of cellulase mixtures on magnetic particles for hydrolysis of lignocellulose and ease of recycling

DEFF Research Database (Denmark)

Alftrén, Johan; Hobley, Timothy John

2014-01-01

In the present study whole cellulase mixtures were covalently immobilized on non-porous magnetic particles to enable enzyme reuse. It was shown that CellicCTec2 immobilized on magnetic particles activated with cyanuric chloride gave the highest bead activity measured by mass of reducing sugar...... serum albumin (BSA)) on hydrolysis yield was studied for free and immobilized CellicCTec2. It was observed that for both free and immobilized CellicCTec2 the hydrolysis yield was increased when Tween 80, PEG 6000 or BSA was included. Interaction between magnetic particles (containing immobilized Cellic......CTec2) and lignin was examined and it was demonstrated that addition of BSA completely inhibited interaction while Tween 80 and PEG 6000 had no effect on decreasing magnetic particle-lignin interaction. Hydrolysis of pretreated wheat straw biomass was performed in two consecutive cycles using...

Hanford immobilized LAW product acceptance: Initial Tanks Focus Area testing data package

Energy Technology Data Exchange (ETDEWEB)

JD Vienna; A Jiricka; BP McGrail; BM Jorgensen; DE Smith; BR Allen; JC Marra; DK Peeler; KG Brown; IA Reamer; WL Ebert

2000-03-08

The Hanford Site's mission has been to produce nuclear materials for the US Department of Energy (DOE) and its predecessors. A large inventory of radioactive and mixed waste, largely generated during plutonium production, exists in 177 underground single- and double-shell tanks. These wastes are to be retrieved and separated into low-activity waste (LAW) and high-level waste (HLW) fractions. The total volume of LAW requiring immobilization will include the LAW separated from the tank waste, as well as new wastes generated by the retrieval, pretreatment, and immobilization processes. Per the Tri-Party Agreement (1994), both the LAW and HLW will be vitrified. It has been estimated that vitrification of the LAW waste will result in over 500,000 metric tons or 200,000 m{sup 3} of immobilized LAW (ILAW) glass. The ILAW glass is to be disposed of onsite in a near-surface burial facility. It must be demonstrated that the disposal system will adequately retain the radionuclides and prevent contamination of the surrounding environment. This report describes a study of the impacts of systematic glass-composition variation on the responses from accelerated laboratory corrosion tests of representative LAW glasses. A combination of two tests, the product consistency test and vapor-hydration test, is being used to give indictations of the relative rate at which a glass could be expected to corrode in the burial scenario.

Hanford immobilized LAW product acceptance: Initial Tanks Focus Area testing data package

International Nuclear Information System (INIS)

JD Vienna; A Jiricka; BP McGrail; BM Jorgensen; DE Smith; BR Allen; JC Marra; DK Peeler; KG Brown; IA Reamer; WL Ebert

2000-01-01

The Hanford Site's mission has been to produce nuclear materials for the US Department of Energy (DOE) and its predecessors. A large inventory of radioactive and mixed waste, largely generated during plutonium production, exists in 177 underground single- and double-shell tanks. These wastes are to be retrieved and separated into low-activity waste (LAW) and high-level waste (HLW) fractions. The total volume of LAW requiring immobilization will include the LAW separated from the tank waste, as well as new wastes generated by the retrieval, pretreatment, and immobilization processes. Per the Tri-Party Agreement (1994), both the LAW and HLW will be vitrified. It has been estimated that vitrification of the LAW waste will result in over 500,000 metric tons or 200,000 m 3 of immobilized LAW (ILAW) glass. The ILAW glass is to be disposed of onsite in a near-surface burial facility. It must be demonstrated that the disposal system will adequately retain the radionuclides and prevent contamination of the surrounding environment. This report describes a study of the impacts of systematic glass-composition variation on the responses from accelerated laboratory corrosion tests of representative LAW glasses. A combination of two tests, the product consistency test and vapor-hydration test, is being used to give indictations of the relative rate at which a glass could be expected to corrode in the burial scenario

Immobilization thresholds of electrofishing relative to fish size

Science.gov (United States)

Dolan, C.R.; Miranda, L.E.

2003-01-01

Fish size and electrical waveforms have frequently been associated with variation in electrofishing effectiveness. Under controlled laboratory conditions, we measured the electrical power required by five electrical waveforms to immobilize eight fish species of diverse sizes and shapes. Fish size was indexed by total body length, surface area, volume, and weight; shape was indexed by the ratio of body length to body depth. Our objectives were to identify immobilization thresholds, elucidate the descriptors of fish size that were best associated with those immobilization thresholds, and determine whether the vulnerability of a species relative to other species remained constant across electrical treatments. The results confirmed that fish size is a key variable controlling the immobilization threshold and further suggested that the size descriptor best related to immobilization is fish volume. The peak power needed to immobilize fish decreased rapidly with increasing fish volume in small fish but decreased slowly for fish larger than 75-100 cm 3. Furthermore, when we controlled for size and shape, different waveforms did not favor particular species, possibly because of the overwhelming effect of body size. Many of the immobilization inconsistencies previously attributed to species might simply represent the effect of disparities in body size.

Changes in corticospinal transmission following 8 weeks of ankle joint immobilization

DEFF Research Database (Denmark)

Leukel, Christian; Taube, Wolfgang; Rittweger, Jörn

2015-01-01

) of the primary motor cortex (Hcond). This method allows assessment of transmission in fast (monosynaptic) and slow(er) (polysynaptic) corticospinal pathways. METHODS: 9 subjects underwent 8weeks of unilateral ankle joint immobilization during daytime, 7 subjects served as controls. The measures obtained before...... and after immobilization included stretch- and H-reflexes assessing excitability of the spinal reflex circuitries, TMS recruitment curves estimating overall changes in corticospinal excitability, and Hcond. RESULTS: TMS recruitment curves showed an overall increase in corticospinal excitability following...

Co-immobilization of semaphorin3A and nerve growth factor to guide and pattern axons.

Science.gov (United States)

McCormick, Aleesha M; Jarmusik, Natalie A; Leipzig, Nic D

2015-12-01

Immobilization of axon guidance cues offers a powerful tissue regenerative strategy to control the presentation and spatial location of these biomolecules. We use our previously developed immobilization strategy to specifically tether recombinant biotinylated nerve growth factor (bNGF) and biotinylated semaphorin3A (bSema3A) to chitosan films as an outgrowth and guidance platform. DRG neurite length and number for a range of single cues of immobilized bNGF or bSema3A were examined to determine a concentration response. Next single and dual cues of bNGF and bSema3A were immobilized and DRG guidance was assessed in response to a step concentration change from zero. Overall, immobilized groups caused axon extension, retraction and turning depending on the ratio of bNGF and bSema3A immobilized in the encountered region. This response indicated the exquisite sensitivity of DRG axons to both attractive and repulsive tethered cues. bSema3A concentrations of 0.10 and 0.49 ng/mm(2), when co-immobilized with bNGF (at 0.86 and 0.43 ng/mm(2) respectively), caused axons to turn away from the co-immobilized region. Immunocytochemical analysis showed that at these bSema3A concentrations, axons inside the co-immobilized region display microtubule degradation and breakdown of actin filaments. At the lowest bSema3A concentration (0.01 ng/mm(2)) co-immobilized with a higher bNGF concentration (2.16 ng/mm(2)), neurite lengths are shorter in the immobilized area, but bNGF dominates the guidance mechanism as neurites are directed toward the immobilized region. Future applications can pattern these cues in various geometries and gradients in order to better modulate axon guidance in terms of polarity, extension and branching. Nervous system formation and regeneration requires key molecules for guiding the growth cone and nervous system patterning. In vivo these molecules work in conjunction with one another to modulate axon guidance, and often they are tethered to limit spatial

Immobilization of Lactobacillus rhamnosus in mesoporous silica-based material: An efficiency continuous cell-recycle fermentation system for lactic acid production.

Science.gov (United States)

Zhao, Zijian; Xie, Xiaona; Wang, Zhi; Tao, Yanchun; Niu, Xuedun; Huang, Xuri; Liu, Li; Li, Zhengqiang

2016-06-01

Lactic acid bacteria immobilization methods have been widely used for lactic acid production. Until now, the most common immobilization matrix used is calcium alginate. However, Ca-alginate gel disintegrated during lactic acid fermentation. To overcome this deficiency, we developed an immobilization method in which Lactobacillus rhamnosus cells were successfully encapsulated into an ordered mesoporous silica-based material under mild conditions with a high immobilization efficiency of 78.77% by using elemental analysis. We also optimized the cultivation conditions of the immobilized L. rhamnosus and obtained a high glucose conversion yield of 92.4%. Furthermore, L. rhamnosus encapsulated in mesoporous silica-based material exhibited operational stability during repeated fermentation processes and no decrease in lactic acid production up to 8 repeated batches. Copyright © 2016 The Society for Biotechnology, Japan. Published by Elsevier B.V. All rights reserved.

Ceramic membrane microfilter as an immobilized enzyme reactor.

Science.gov (United States)

Harrington, T J; Gainer, J L; Kirwan, D J

1992-10-01

This study investigated the use of a ceramic microfilter as an immobilized enzyme reactor. In this type of reactor, the substrate solution permeates the ceramic membrane and reacts with an enzyme that has been immobilized within its porous interior. The objective of this study was to examine the effect of permeation rate on the observed kinetic parameters for the immobilized enzyme in order to assess possible mass transfer influences or shear effects. Kinetic parameters were found to be independent of flow rate for immobilized penicillinase and lactate dehydrogenase. Therefore, neither mass transfer nor shear effects were observed for enzymes immobilized within the ceramic membrane. Both the residence time and the conversion in the microfilter reactor could be controlled simply by regulating the transmembrane pressure drop. This study suggests that a ceramic microfilter reactor can be a desirable alternative to a packed bed of porous particles, especially when an immobilized enzyme has high activity and a low Michaelis constant.

Plutonium Immobilization Can Loading Equipment Review

International Nuclear Information System (INIS)

Kriikku, E.; Ward, C.; Stokes, M.; Randall, B.; Steed, J.; Jones, R.; Hamilton, L.

1998-05-01

This report lists the operations required to complete the Can Loading steps on the Pu Immobilization Plant Flow Sheets and evaluates the equipment options to complete each operation. This report recommends the most appropriate equipment to support Plutonium Immobilization Can Loading operations

In vivo immobilization of fusion proteins on bioplastics by the novel tag BioF.

Science.gov (United States)

Moldes, Cristina; García, Pedro; García, José L; Prieto, María A

2004-06-01

A new protein immobilization and purification system has been developed based on the use of polyhydroxyalkanoates (PHAs, or bioplastics), which are biodegradable polymers accumulated as reserve granules in the cytoplasm of certain bacteria. The N-terminal domain of the PhaF phasin (a PHA-granule-associated protein) from Pseudomonas putida GPo1 was used as a polypeptide tag (BioF) to anchor fusion proteins to PHAs. This tag provides a novel way to immobilize proteins in vivo by using bioplastics as supports. The granules carrying the BioF fusion proteins can be isolated by a simple centrifugation step and used directly for some applications. Moreover, when required, a practically pure preparation of the soluble BioF fusion protein can be obtained by a mild detergent treatment of the granule. The efficiency of this system has been demonstrated by constructing two BioF fusion products, including a functional BioF-beta-galactosidase. This is the first example of an active bioplastic consisting of a biodegradable matrix carrying an active enzyme.

Geometry-dependent DNA-TiO2 immobilization mechanism: A spectroscopic approach

Science.gov (United States)

Silva-Moraes, M. O.; Garcia-Basabe, Y.; de Souza, R. F. B.; Mota, A. J.; Passos, R. R.; Galante, D.; Fonseca Filho, H. D.; Romaguera-Barcelay, Y.; Rocco, M. L. M.; Brito, W. R.

2018-06-01

DNA nucleotides are used as a molecular recognition system on electrodes modified to be applied in the detection of various diseases, but immobilization mechanisms, as well as, charge transfers are not satisfactorily described in the literature. An electrochemical and spectroscopic study was carried out to characterize the molecular groups involved in the direct immobilization of DNA structures on the surface of nanostructured TiO2 with the aim of evaluating the influence of the geometrical aspects. X-ray photoelectron spectroscopy at O1s and P2p core levels indicate that immobilization of DNA samples occurs through covalent (Psbnd Osbnd Ti) bonds. X-ray absorption spectra at the Ti2p edge reinforce this conclusion. A new species at 138.5 eV was reported from P2p XPS spectra analysis which plays an important role in DNA-TiO2 immobilization. The Psbnd Osbnd Ti/Osbnd Ti ratio showed that quantitatively the DNA immobilization mechanism is dependent on their geometry, becoming more efficient for plasmid ds-DNA structures than for PCR ds-DNA structures. The analysis of photoabsorption spectra at C1s edge revealed that the molecular groups that participate in the C1s → LUMO electronic transitions have different pathways in the charge transfer processes at the DNA-TiO2 interface. Our results may contribute to additional studies of immobilization mechanisms understanding the influence of the geometry of different DNA molecules on nanostructured semiconductor and possible impact to the charge transfer processes with application in biosensors or aptamers.

Development of High-Productivity Continuous Ethanol Production using PVA-Immobilized Zymomonas mobilis in an Immobilized-Cells Fermenter

Directory of Open Access Journals (Sweden)

Nurhayati Nurhayati

2015-07-01

Full Text Available Ethanol as one of renewable energy was being considered an excellent alternative clean-burning fuel to replace gasoline. Continuous ethanol fermentation systems had offered important economic advantages compared to traditional systems. Fermentation rates were significantly improved, especially when continuous fermentation was integrated with cell immobilization techniques to enrich the cells concentration in fermentor. Growing cells of Zymomonas mobilis immobilized in polyvinyl alcohol (PVA gel beads were employed in an immobilized-cells fermentor for continuous ethanol fermentation from glucose. The glucose loading, dilution rate, and cells loading were varied in order to determine which best condition employed in obtaining both high ethanol production and low residual glucose with high dilution rate. In this study, 20 g/L, 100 g/L, 125 g/L and 150 g/L of glucose concentration and 20% (w/v, 40% (w/v and 50% (w/v of cells loading were employed with range of dilution rate at 0.25 to 1 h-1. The most stable production was obtained for 25 days by employing 100 g/L of glucose loading. Meanwhile, the results also exhibited that 125 g/L of glucose loading as well as 40% (w/v of cells loading yielded high ethanol concentration, high ethanol productivity, and acceptable residual glucose at 62.97 g/L, 15.74 g/L/h and 0.16 g/L, respectively. Furthermore, the dilution rate of 4 hour with 100 g/L and 40% (w/v of glucose and cells loading was considered as the optimum condition with ethanol production, ethanol productivity and residual glucose obtained were 49.89 g/L, 12.47 g/L/h, and 2.04 g/L, respectively. This recent study investigated ethanol inhibition as well. The present research had proved that high sugar concentration was successfully converted to ethanol. These achieved results were promising for further study.

Characterization of immobilized post-carbohydrate meal salivary α ...

African Journals Online (AJOL)

The effect of experimental parameters like pH, temperature and substrate concentration on the activity of the immobilized post-carbohydrate meal salivary ... of immobilized post-carbohydrate meal salivary α-amylase in this study show that immobilization had no significant effect on the enzyme and compared to kinetic ...

Immobilization of thorium over fibroin by polyacrylonitrile (PAN)

International Nuclear Information System (INIS)

Aslani, M.A.A.; Akyil, S.; Eral, M.

1997-01-01

This report describes a process for immobilization of thorium over fibroin, which was used as a bio-adsorbant, by polyacrylonitrile. The amounts of thorium in aqueous solutions which may be leached in various aqueous ambients were detected by a spectrophotometer. The results show that polyacrylonitrile processes are feasible to immobilize spent fibroins. The leachability of the materials immobilized with polyacrylonitrile can meet the requirements of storage and final disposal. The leachability of thorium ions from immobilized spent fibroin was rather low for 8 months

Immobilization of ammonia-oxidizing bacteria by polyvinyl alcohol and sodium alginate.

Science.gov (United States)

Dong, Yuwei; Zhang, Yanqiu; Tu, Baojun

Ammonia-oxidizing bacteria were immobilized by polyvinyl alcohol (PVA) and sodium alginate. The immobilization conditions and ammonia oxidation ability of the immobilized bacteria were investigated. The following immobilization conditions were observed to be optimal: PVA, 12%; sodium alginate, 1.1%; calcium chloride, 1.0%; inoculum concentration, 1.3 immobilized balls/mL of immobilized medium; pH, 10; and temperature, 30°C. The immobilized ammonia-oxidizing bacteria exhibited strong ammonia oxidation ability even after being recycled four times. The ammonia nitrogen removal rate of the immobilized ammonia-oxidizing bacteria reached 90.30% under the optimal immobilization conditions. When compared with ammonia-oxidizing bacteria immobilized by sodium alginate alone, the bacteria immobilized by PVA and sodium alginate were superior with respect to pH resistance, the number of reuses, material cost, heat resistance, and ammonia oxidation ability. Copyright © 2017 Sociedade Brasileira de Microbiologia. Published by Elsevier Editora Ltda. All rights reserved.

Immobilization of Saccharomyces Cerevisiae in Rice Hulls for Ethanol Production

Directory of Open Access Journals (Sweden)

Edita Martini

2011-05-01

Full Text Available The whole cell immobilization in ethanol fermentation can be done by using natural carriers or through synthetic carriers. All of these methods have the same purpose of retaining high cell concentrations within a certain defined region of space which leads to higher ethanol productivity. Lignocellulosic plant substance represents one of highly potential sources in ethanol production. Some studies have found that cellulosic substances substances can also be used as a natural carrier in cell immobilization by re-circulating pre-culture medium into a reactor. In this experiment, rice hulls without any treatment were used to immobilize Saccharomyces cerevisiae through semi solid state incubation combined with re-circulating pre-culture medium. The scanning electron microscopy (SEM pictures of the carrier show that the yeast cells are absorbed and embedded to the rice hull pore. In liquid batch fermentation system with an initial sugar concentration of 50 g/L, nearly 100% total sugar was consumed after 48 hours. This resulted in an ethanol yield of 0.32 g ethanol/g glucose, which is 62.7% of the theoretical value. Ethanol productivity of 0.59 g/(L.h is 2.3 fold higher than that of free cells which is 0.26 g/(L.h. An effort to reuse the immobilized cells in liquid fermentation system showed poor results due to cell desorption in the first batch which led to high sugar concentration inhibitory effect in the second batch fermentation. This might be solved by using semi solid fermentation process in the future work.

Investigation of waste form materials suitable for immobilizing actinide elements in high-level waste

International Nuclear Information System (INIS)

Hayakawa, Issei; Kamizono, Hiroshi

1992-07-01

The microstructure of waste form materials suitable for immobilizing actinide elements can be classified into the following two categories. (1) Actinide elements are immobilized in an crystallized matrix after the formation of solid solution or compounds. (2) Actinide elements are immobilized in a durable material by encapsulation. Based on crystal chemistry, durability data, phase diagrams, compositions of natural minerals, eleven oxide compounds and one non-oxide compound are pointed out to be new candidates included in category (1). The other survey on material compositions, manufacturing conditions and feasibility shows that SiC, glassy carbon, ZrO 2 , Ti-O-Si-C ceramics are preferable matrix materials included in category (2). Polymers and fine powders are suitable as starting materials for the encapsulation of actinide elements because of their excellent sinterability. (author) 50 refs

Thermal stability of the immobilized fructosyltransferase from Rhodotorula sp

Directory of Open Access Journals (Sweden)

E Aguiar-Oliveira

2011-09-01

Full Text Available The thermal stability of the extracellular fructosyltransferase (FTase from Rhodotorula sp., recovered from cultivation medium by ethanol precipitation and immobilized onto niobium ore, was studied by Arrhenius plot, half - life profile, half - inactivation temperature (T50 and thermodynamic parameters. The Arrhenius plot showed two different behaviors with different deactivation energies (Ead only after immobilization, the transition occurring in the temperature interval between 51 and 52ºC. T50 for the free enzyme was estimated to be around 62ºC and, after immobilization, 66ºC. After 15 minutes at 52ºC, it was also possible to observe enzymatic activation for both the free and immobilized forms, but greater activation was achieved at pH 4.5 with the immobilized enzyme. Between 47 - 51ºC the immobilized enzyme was more stable than the free enzyme, with pH 6.0 being the more stable condition for the immobilized enzyme. However, above 52ºC the free form was more stable.

Phase transitions of rare earth compounds during immobilization by foamed corundum

International Nuclear Information System (INIS)

Potemkina, T.I.; Zakharov, M.A.; Plotnikova, T.E.

1992-01-01

Expansion of work on the environmentally safe handling of radioactive materials has become very important in recent years. The proposed method for immobilizing radionuclides by injection into a porous matrix and subsequent fixation has a definite advantage over other techniques, because of its simplicity and low cost. This raises a number of problems that require careful study. The authors can distinguish the following: choice of porous matrix materials; thermal decomposition of nitrates directly in the matrix itself, which determines the minimum firing temperature; behavior and properties of oxides produced in nitrate decomposition; conditions for compound formation between injected solutions and matrix material; processes occurring during immobilizer storage. The rare earth nitrate series can be divided into two groups on the basis of behavior during thermal decomposition: the elements preceding and following Gd. The first group includes La, Pr, And Eu, for which decomposition begins simultaneously with conclusion of dehydration; the second includes Dy, Tb, and Yb, for which nitrate group decomposition begins before dehydration is complete. The authors utilized DTA, XPA, and IR analysis to study the physicochemical properties of the immobilizer produced by a single impregnation of the foamed corundum with rare earth (La, Eu, Dy, Tb, and Yb) nitrate solutions and subsequent firing at 900 degrees C for 30 min. The choice of these rare earths was dictated by the fact that the Ln 2 O 3 -AlO 3 system can be divided into three groups on the basis of phase ratios: La-Nd, Sm-Eu, and Gd-Lu. Lanthanide monoaluminates are formed in all these groups, and the difference lies in the other reaction products generated: LnAl 11 O 18 for La-Nd, LnAl 11 O 18 and Ln 4 Al 2 O 9 for Sm-Eu, and Ln 4 Al 2 O 9 and Ln 3 Al 5 O 12 for Gd-Lu

Immobilization of technetium and nitrate in cement-based materials

International Nuclear Information System (INIS)

Tallent, O.K.; McDaniel, E.W.; Del Cul, G.D.; Dodson, K.E.; Trotter, D.R.

1987-01-01

The leachabilities of technetium and nitrate wastes immobilized in cement-based grouts have been investigated. Factors found to affect the leachabilities include grout mix ratio, grout fluid density, dry solid blend composition, and waste concentration. 10 refs., 7 figs., 3 tabs

Testing and evaluation of alternative process systems for immobilizing radioactive mixed particulate waste in cement

International Nuclear Information System (INIS)

Weingardt, K.M.; Weber, J.R.

1994-03-01

Radioactive and Hazardous Mixed Wastes have accumulated at the Department of Energy (DOE) Hanford Site in south-central Washington State. Ongoing operations and planned facilities at Hanford will also contribute to this waste stream. To meet the Resource Conservation and Recovery Act (RCRA) Land Disposal Restrictions most of this waste will need to be treated to permit disposal. In general this treatment will need to include stabilization/solidification either as a sole method or as part of a treatment train. A planned DOE facility, the Waste Receiving and Processing (WRAP) Module 2A, is scoped to provide this required treatment for containerized contact-handled (CH), mixed low-level waste (MLLW) at Hanford. An engineering development program has been conducted by Westinghouse Hanford Company (WHC) to select the best system for utilizing a cement based process in WRAP Module 2A. Three mixing processes were developed for analysis and testing; in-drum mixing, continuous mixing, and batch mixing. Some full scale tests were conducted and 55 gallon drums of solidified product were produced. These drums were core sampled and examined to evaluate mixing effectiveness. Total solids loading and the order of addition of waste and binder constituents were also varied. The highest confidence approach to meet the WRAP Module 2A waste immobilization system needs appears to be the out-of-drum batch mixing concept. This system is believed to offer the most flexibility and efficiency, given the highly variable and troublesome waste streams feeding the facility

Recent Developments in the Site-Specific Immobilization of Proteins onto Solid Supports

Energy Technology Data Exchange (ETDEWEB)

Camarero, J A

2007-02-21

Immobilization of proteins onto surfaces is of great importance in numerous applications, including protein analysis, drug screening, and medical diagnostics, among others. The success of all these technologies relies on the immobilization technique employed to attach a protein to the corresponding surface. Non-specific physical adsorption or chemical cross-linking with appropriate surfaces results in the immobilization of the protein in random orientations. Site-specific covalent attachment, on the other hand, leads to molecules being arranged in a definite, orderly fashion and allows the use of spacers and linkers to help minimize steric hindrances between the protein and the surface. The present work reviews the latest chemical and biochemical developments for the site-specific covalent attachment of proteins onto solid supports.

Enzyme immobilization and biocatalysis of polysiloxanes

Science.gov (United States)

Poojari, Yadagiri

H, temperature, cross-link density, organic solvents and storage time using a hemoglobin assay. A notable finding was that free pepsin had zero activity in neutral buffer solution (pH 7) after incubation for 5 hours, while pepsin immobilized in the silicone elastomers was found to retain more than 70% of its maximum normalized activity. These results demonstrate that cross-linked poly(dimethylsiloxane) (PDMS) is a promising support material for the physical entrapment of hydrolytic enzymes such as pepsin. The Novozym-435 has been widely employed as a biocatalyst for esterification and transesterification of a variety of organic compounds including synthesis of polyesters and polylactones due to its high catalytic-efficiency and high thermal stability in organic media. However, the Novozym-435 was found to have poor mechanical stability and the enzyme was found to leach out from the resin into the organic media. In the present research work, efforts were made to solve the above two problems by chemical immobilization of CALB on surface modified porous silica gel particles. The surface of the porous silica gel particles was silanized using (gamma-Aminopropyl)triethoxysilane and then the CALB was chemically crosslinked onto the surface of the silica gel particles using glutaraldehyde. Although the thermal stability of the CALB immobilized silica gel particles was found to be lower compared to that of Novozym-435. The CALB immobilized silica gel particles showed higher enzymatic activity and higher mechanical stability compared to that of Novozym-435.

A study on immobilized ethanol yeast cells by radiation technique

International Nuclear Information System (INIS)

Li Zhengkui; Zhang Bosen

1994-01-01

Hydrophilic monomer 2-hydroxyethyl acrylate (HEA) and a series of polyethylene glycol dimethacrylate monomers were copolymerized by radiation technique at low temperature (-78 degree C) and hydrophilic hydrogels were obtained. The immobilization of yeast cells with these copolymer carriers led to a higher ethanol productivity than free cells. Of all copolymer carriers, the ethanol yield with poly (HEA-14 G) was the highest, about 2.45 times as high as that of free yeast cells. In addition, the ethanol productivity of 12 batch repeated reactions with poly (HEA-14G) carrier was all higher than that of free yeast cells. The ethanol productivity of immobilized yeast cells was dependent on the proportion of hydrophilic monomer to other monomers in copolymer systems, the chain length of the bifunctional monomer, the degree of hydration of copolymer carriers, the structure of copolymer carriers and porosity in the internal structure of carriers. The ethanol yield of immobilized cells depended on swelling ability and porosity of copolymer carriers

Preparation and characterization of immobilized lipase on magnetic hydrophobic microspheres

DEFF Research Database (Denmark)

Guo, Zheng; Bai, Shu; Sun, Yan

2003-01-01

H for the immobilized CCL were determined. Activity amelioration of the immobilized CCL for the hydrolysis of olive oil was observed, indicating an interfacial activation of the enzyme after immobilization. Moreover, the immobilized CCL showed enhanced thermal stability and good durability in the repeated use after...

Short-Term Limb Immobilization Affects Cognitive Motor Processes

Science.gov (United States)

Toussaint, Lucette; Meugnot, Aurore

2013-01-01

We examined the effects of a brief period of limb immobilization on the cognitive level of action control. A splint placed on the participants' left hand was used as a means of immobilization. We used a hand mental rotation task to investigate the immobilization-induced effects on motor imagery performance (Experiments 1 and 2) and a number mental…

The characterization and testing of candidate immobilization forms for the disposal of plutonium

International Nuclear Information System (INIS)

Bakel, A. J.; Buck, E. C.; Chamberlain, D. B.; Ebbinghaus, B. B.; Fortner, J. A.; Marra, J. C.; Mcgrail, B. P.; Mertz, C. J.; Peeler, D. K.; Shaw, H. F.; Strachan, D. M.; Van Konynenburg, R. A.; Vienna, J. D.; Wolf, S. F.

1997-01-01

Candidate immobilization forms for the disposal of surplus weapons-useable are being tested and characterized. The goal of the testing program was to provide sufficient data that, by August 1997, an informed selection of a single immobilization form could be made so that the form development and production R and D could be more narrowly focused. Two forms have been under consideration for the past two years: glass and ceramic. In August, 1997, the Department of Energy (DOE) selected ceramic for plutonium disposition, halting further work on the glass material. In this paper, we will briefly describe these two waste forms, then describe our characterization techniques and testing methods. The analytical methods used to characterize altered and unaltered samples are the same. A full suite of microscopic techniques is used. Techniques used include optical, scanning electron, and transmission electron microscopies. For both candidate immobilization forms, the analyses are used to characterize the material for the presence of crystalline phases and amorphous material. Crystalline materials, either in the untested immobilization form or in the alteration products from testing, are characterized with respect to morphology, crystal structure, and composition. The goal of these analyses is to provide data on critical issues such as Pu and neutron absorber volubility in the immobilization form, thermal stability, potential separation of absorber and Pu, and the long-term behavior of the materials. Results from these analyses will be discussed in the presentation. Testing methods include MCC-1 tests, product consistency tests (methods A and B), unsaturated ''drip'' tests, vapor hydration tests, single-pass flow-through tests, and pressurized unsaturated flow tests. Both candidate immobilization forms have very low dissolution rates; examples of typical test results will be reported

Oral creatine supplementation attenuates muscle loss caused by limb immobilization: a systematic review

Directory of Open Access Journals (Sweden)

Camila Souza Padilha

Full Text Available Abstract Introduction: Recent studies have pointing creatine supplementation as a promising therapeutic alterna- tive in several diseases, especially myopathies and neurodegenerative disorder. Objective: elucidate the role of creatine supplementation on deleterious effect caused by limb immobilization in humans and rats. Methods: Analyzed articles were searched by three online databases, PubMed, SportDicus e Scielo. After a review and analysis, the studies were included in this review articles on effect of creatine supplementation on skeletal muscle in humans and rat, before, during and after a period of limb immobilization. Results: Studies analyzed demonstrated positive points in use of creatine supplementation as a therapeutic tool to mitigating the deleterious effects of limb immobilization, in humans and rat. Conclusion: The dataset of this literature review allows us to conclude that creatine supplementation may reduce muscle loss and/or assist in the recovery of muscle atrophy caused by immobilization and disuse in rats and humans. Also, we note that further research with better methodological rigor is needed to clarify the mechanisms by which creatine support the recovery of muscle atrophy. Moreover, these effects are positive and promising in the field of muscle rehabilitation, especially after member’s immobilization.

Stable functionalization of germanium surface and its application in biomolecules immobilization

Energy Technology Data Exchange (ETDEWEB)

Cai, Qi [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); University of Chinese Academy of Sciences, No.19A, Yuquan Road, Beijing 100049 (China); Xu, Baojian [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); Ye, Lin [Sate Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); University of Chinese Academy of Sciences, No.19A, Yuquan Road, Beijing 100049 (China); Tang, Teng; Huang, Shanluo; Du, Xiaowei [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); University of Chinese Academy of Sciences, No.19A, Yuquan Road, Beijing 100049 (China); Bian, Xiaojun; Zhang, Jishen [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); Di, Zengfeng, E-mail: zfdi@mail.sim.ac.cn [Sate Key Laboratory of Functional Materials for Informatics, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); Jin, Qinghui [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China); Zhao, Jianlong, E-mail: jlzhao@mail.sim.ac.cn [State Key Laboratory of Transducer Technology, Shanghai Institute of Microsystem and Information Technology, Chinese Academy of Sciences, No.865, Changning Road, Shanghai 200050 (China)

2014-10-15

Highlights: • An effective method to immobilize biomolecules on the functionalized Ge surface. • The surface of Ge was functionalized with 11-Mercaptoundecanoic acid (11-MUA). • Stable and uniform SAMs was obtained on Ge surface after 11-MUA treatment. • The functionalized Ge was employed as substrate for protein immobilization. • Paving the way of Ge for further applications in bioelectronics field. - Abstract: As a typical semiconductor material, germanium (Ge) has the potential to be utilized in microelectronics and bioelectronics. Herein, we present a simple and effective method to immobilize biomolecules on the surface of functionalized Ge. The surface oxide of Ge was removed with the pretreatment of hydrochloric acid and the Cl-terminated Ge reacted with 11-Mercaptoundecanoic acid (11-MUA). The surface of Ge was coated with 11-MUA self-assembled monolayers (SAMs) due to the bonding reaction between the sulfhydryl group of 11-MUA and Cl-terminated Ge. Furthermore, typical biomolecule, a green fluorescent protein was chosen to be immobilized on the surface of the functionalized Ge. Contact angle analysis, atomic force microscopy and X-ray photoelectron spectroscopy were used to study the characteristics including wettability, stability, roughness and component of the functionalized Ge, respectively. Fluorescence microscopy was utilized to indicate the efficiency of protein immobilization on the surface of the functionalized Ge. With these studies, stable and uniform functionalized monolayer was obtained on the surface of Ge after 11-MUA treatment and the functionalized Ge was effectively applied in protein immobilization. Furthermore, this study may pave the way for further applications such as the integration of bioelectronics and biosensors with the attractive semiconductor material-Ge in future work.

Polymer-assisted iron oxide magnetic nanoparticle immobilized keratinase

Energy Technology Data Exchange (ETDEWEB)

Konwarh, Rocktotpal; Karak, Niranjan [Advanced Polymer and Nanomaterial Laboratory, Department of Chemical Sciences, Tezpur University, Tezpur-784028, Assam (India); Rai, Sudhir Kumar; Mukherjee, Ashis Kumar [Department of Molecular Biology and Biotechnology, Tezpur University, Tezpur-784028, Assam (India)], E-mail: karakniranjan@yahoo.com

2009-06-03

Nanotechnology holds the prospect for avant-garde changes to improve the performance of materials in various sectors. The domain of enzyme biotechnology is no exception. Immobilization of industrially important enzymes onto nanomaterials, with improved performance, would pave the way to myriad application-based commercialization. Keratinase produced by Bacillus subtilis was immobilized onto poly(ethylene glycol)-supported Fe{sub 3}O{sub 4} superparamagnetic nanoparticles. The optimization process showed that the highest enzyme activity was noted when immobilized onto cyanamide-activated PEG-assisted MNP prepared under conditions of 25 deg. C and pH 7.2 of the reaction mixture before addition of H{sub 2}O{sub 2} (3% w/w), 2% (w/v) PEG{sub 6000} and 0.062:1 molar ratio of PEG to FeCl{sub 2}{center_dot}4H{sub 2}O. Further statistical optimization using response surface methodology yielded an R{sup 2} value that could explain more than 94% of the sample variations. Along with the magnetization studies, the immobilization of the enzyme onto the PEG-assisted MNP was characterized by UV, XRD, FTIR and TEM. The immobilization process had resulted in an almost fourfold increase in the enzyme activity over the free enzyme. Furthermore, the immobilized enzyme exhibited a significant thermostability, storage stability and recyclability. The leather-industry-oriented application of the immobilized enzyme was tested for the dehairing of goat-skin.

Polymer-assisted iron oxide magnetic nanoparticle immobilized keratinase

International Nuclear Information System (INIS)

Konwarh, Rocktotpal; Karak, Niranjan; Rai, Sudhir Kumar; Mukherjee, Ashis Kumar

2009-01-01

Nanotechnology holds the prospect for avant-garde changes to improve the performance of materials in various sectors. The domain of enzyme biotechnology is no exception. Immobilization of industrially important enzymes onto nanomaterials, with improved performance, would pave the way to myriad application-based commercialization. Keratinase produced by Bacillus subtilis was immobilized onto poly(ethylene glycol)-supported Fe 3 O 4 superparamagnetic nanoparticles. The optimization process showed that the highest enzyme activity was noted when immobilized onto cyanamide-activated PEG-assisted MNP prepared under conditions of 25 deg. C and pH 7.2 of the reaction mixture before addition of H 2 O 2 (3% w/w), 2% (w/v) PEG 6000 and 0.062:1 molar ratio of PEG to FeCl 2 ·4H 2 O. Further statistical optimization using response surface methodology yielded an R 2 value that could explain more than 94% of the sample variations. Along with the magnetization studies, the immobilization of the enzyme onto the PEG-assisted MNP was characterized by UV, XRD, FTIR and TEM. The immobilization process had resulted in an almost fourfold increase in the enzyme activity over the free enzyme. Furthermore, the immobilized enzyme exhibited a significant thermostability, storage stability and recyclability. The leather-industry-oriented application of the immobilized enzyme was tested for the dehairing of goat-skin.

Polymer-assisted iron oxide magnetic nanoparticle immobilized keratinase

Science.gov (United States)

Konwarh, Rocktotpal; Karak, Niranjan; Rai, Sudhir Kumar; Mukherjee, Ashis Kumar

2009-06-01

Nanotechnology holds the prospect for avant-garde changes to improve the performance of materials in various sectors. The domain of enzyme biotechnology is no exception. Immobilization of industrially important enzymes onto nanomaterials, with improved performance, would pave the way to myriad application-based commercialization. Keratinase produced by Bacillus subtilis was immobilized onto poly(ethylene glycol)-supported Fe3O4 superparamagnetic nanoparticles. The optimization process showed that the highest enzyme activity was noted when immobilized onto cyanamide-activated PEG-assisted MNP prepared under conditions of 25 °C and pH 7.2 of the reaction mixture before addition of H2O2 (3% w/w), 2% (w/v) PEG6000 and 0.062:1 molar ratio of PEG to FeCl2·4H2O. Further statistical optimization using response surface methodology yielded an R2 value that could explain more than 94% of the sample variations. Along with the magnetization studies, the immobilization of the enzyme onto the PEG-assisted MNP was characterized by UV, XRD, FTIR and TEM. The immobilization process had resulted in an almost fourfold increase in the enzyme activity over the free enzyme. Furthermore, the immobilized enzyme exhibited a significant thermostability, storage stability and recyclability. The leather-industry-oriented application of the immobilized enzyme was tested for the dehairing of goat-skin.

The effectiveness of immobilization during prostate irradiation

International Nuclear Information System (INIS)

Bentel, Gunilla C.; Marks, Lawrence B.; Sherouse, George W.; Spencer, David P.; Anscher, Mitchell S.

1995-01-01

Purpose: To evaluate the effect of a hemibody foam cradle on the reproducibility of patient setup during external beam radiation treatment of prostate cancer. Methods and Materials: Between January 1992 and April 1993, 74 patients received external beam radiation treatment to the prostate ± nodes, generally with a four-field box technique. Forty-four of the 74 patients had a custom-made hemibody foam cast used in an attempt to improve setup accuracy. A review of the routine weekly port films was performed following the completion of therapy to determine the reproducibility of patient setup in all 74 patients. The physician's request of an isocenter shift was used as an indicator of reproducibility. Neither the treating technologists nor the physicians knew at the time the films were taken that the port films would be reviewed for setup reproducibility at a later date. The results were compared between the patients treated with (44) and without (30) an immobilization device. Results: In the 44 immobilized patients, 213 routine checks of the isocenter were performed during the 7-week course of radiation therapy. In 17.4% of these instances (37 out of 213), an isocenter shift was requested. This rate is compared to 23.1% (30 out of 130) in the 30 patients who did not have the immobilization device (p < 0.2). There was a statistically significant reduction in isocenter shifts requested in the anterior to posterior direction in the patients who were immobilized, 5.1% (9 out of 175) vs. 12.6% (13 out of 103) (p < 0.05, two tailed chi-square test). There was no significant improvement in the reproducibility of isocenter placement in the cephalad to caudal or right to left directions. Conclusions: This custom-made hemibody foam cradle appears to improve the reproducibility of patient setup during the 7-week course of fractionated external beam irradiation for patients with adenocarcinoma of the prostate. This type of immobilization device is now routinely used in our

Activity and stability of immobilized lipases in lipase-catalyzed modification of peanut oil

Directory of Open Access Journals (Sweden)

Soumanou Mohamed M.

2004-11-01

Full Text Available Fatty acid release during lipolysis of peanut oil using microbial free and immobilized lipases in aqueous media was developed. Immobilized lipase from Rhizomucor miehei (RML gave the best result from its ability to clive different fatty acids from peanut oil in such media. In organic solvent, interesterification of peanut oil with tricaprylin using immobilized lipases from RML, Chromobacterium viscosum (CVL and Candida rugosa (CRL was performed. The best substrate molar ratio of tricaprylin to peanut oil found was in the range 0.7 to 0.8. Using substrate molar ratio 0.7, high amount of structured triglyceride ST (about 35% MLM, 44% LML triglyceride fractions was obtained with lipase from RML in n-hexane. The results found in solvent free system were in some cases quite similar to that obtained in organic solvent. In nine successive batch interesterification in solvent free medium using immobilized RML and CRL, no significant loss of amount of both produced triacylglycerol fractions until batch 7 was observed with RML.

Options for the Separation and Immobilization of Technetium

International Nuclear Information System (INIS)

Serne, R Jeffrey; Crum, Jarrod V.; Riley, Brian J.; Levitskaia, Tatiana G.

2016-01-01

Among radioactive constituents present in the Hanford tank waste, technetium-99 (Tc) presents a unique challenge in that it is significantly radiotoxic, exists predominantly in the liquid low-activity waste (LAW), and has proven difficult to effectively stabilize in a waste form for ultimate disposal. Within the Hanford Tank Waste Treatment and Immobilization Plant, the LAW fraction will be converted to a glass waste form in the LAW vitrification facility, but a significant fraction of Tc volatilizes at the high glass-melting temperatures and is captured in the off-gas treatment system. This necessitates recycle of the off-gas condensate solution to the LAW glass melter feed. The recycle process is effective in increasing the loading of Tc in the immobilized LAW (ILAW), but it also disproportionately increases the sulfur and halides in the LAW melter feed, which have limited solubility in the LAW glass and thus significantly reduce the amount of LAW (glass waste loading) that can be vitrified and still maintain good waste form properties. This increases both the amount of LAW glass and either the duration of the LAW vitrification mission or requires the need for supplemental LAW treatment capacity. Several options are being considered to address this issue. Two approaches attempt to minimize the off-gas recycle by removing Tc at one of several possible points within the tank waste processing flowsheet. The separated Tc from these two approaches must then be dispositioned in a manner such that the Tc can be safely disposed. Alternative waste forms that do not have the Tc volatility issues associated with the vitrification process are being sought for immobilization of Tc for subsequent storage and disposal. The first objective of this report is to provide insights into the compositions and volumes of the Tc-bearing waste streams including the ion exchange eluate from processing LAW and the off-gas condensate from the melter. The first step to be assessed will be the

Options for the Separation and Immobilization of Technetium

Energy Technology Data Exchange (ETDEWEB)

Serne, R Jeffrey [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Crum, Jarrod V. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Riley, Brian J. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States); Levitskaia, Tatiana G. [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-09-30

Among radioactive constituents present in the Hanford tank waste, technetium-99 (Tc) presents a unique challenge in that it is significantly radiotoxic, exists predominantly in the liquid low-activity waste (LAW), and has proven difficult to effectively stabilize in a waste form for ultimate disposal. Within the Hanford Tank Waste Treatment and Immobilization Plant, the LAW fraction will be converted to a glass waste form in the LAW vitrification facility, but a significant fraction of Tc volatilizes at the high glass-melting temperatures and is captured in the off-gas treatment system. This necessitates recycle of the off-gas condensate solution to the LAW glass melter feed. The recycle process is effective in increasing the loading of Tc in the immobilized LAW (ILAW), but it also disproportionately increases the sulfur and halides in the LAW melter feed, which have limited solubility in the LAW glass and thus significantly reduce the amount of LAW (glass waste loading) that can be vitrified and still maintain good waste form properties. This increases both the amount of LAW glass and either the duration of the LAW vitrification mission or requires the need for supplemental LAW treatment capacity. Several options are being considered to address this issue. Two approaches attempt to minimize the off-gas recycle by removing Tc at one of several possible points within the tank waste processing flowsheet. The separated Tc from these two approaches must then be dispositioned in a manner such that the Tc can be safely disposed. Alternative waste forms that do not have the Tc volatility issues associated with the vitrification process are being sought for immobilization of Tc for subsequent storage and disposal. The first objective of this report is to provide insights into the compositions and volumes of the Tc-bearing waste streams including the ion exchange eluate from processing LAW and the off-gas condensate from the melter. The first step to be assessed will be the

Evaluation Of Enzyme Immobilization Methods For Paper-based Devices-a Glucose Oxidase Study

OpenAIRE

Nery; Emilia Witkowska; Kubota; Lauro T.

2016-01-01

Paper-based sensors gained almost explosive attention during the last few years. A large number of systems, often destined to resource limited settings is based on enzymatic reactions. Choice of an adequate immobilization method could significantly prolong the shelf-life of such sensors, especially in applications, where exposure to high temperatures during storage and transport is more than a threat. We are seeking to compare a variety of immobilization methods based on different phenomena (...

Biosorption of americium-241 by immobilized Rhizopus arrihizus

International Nuclear Information System (INIS)

Liao Jiali; Yang Yuanyou; Luo Shunzhong; Liu Ning; Jin Jiannan; Zhang Taiming; Zhao Pengji

2004-01-01

Rhizopus arrihizus (R. arrihizus), a fungus, which in previous experiments had shown encouraging ability to remove 241 Am from solutions, was immobilized by calcium alginate and other reagents. The various factors affecting 241 Am biosorption by the immobilized R. arrihizus were investigated. The results showed that not only can immobilized R. arrihizus adsorb 241 Am as efficiently as free R. arrihizus, but that also can be used repeatedly or continuously. The biosorption equilibrium was achieved within 2 h, and more than 94% of 241 Am was removed from 241 Am solutions of 1.08 MBq/l by immobilized R. arrihizu in the pH range 1-7. Temperature did not affect the adsorption on immobilized R. arrihizus in the range 15-45 deg. C. After repeated adsorption for 8 times, the immobilized R. arrihizus still adsorbed more than 97% of 241 Am. At this time, the total adsorption of 241 Am was more than 88.6 KBq/g, and had not yet reached saturation. Ninety-five percent of the adsorbed 241 Am was desorbed by saturated EDTA solution and 98% by 2 mol/l HNO 3

Stability of immobilized candida sp. 99-125 Lipase for biodiesel production

Energy Technology Data Exchange (ETDEWEB)

Lu, J. [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing (China); Bioengineering Department, Zhengzhou University, Zhengzhou (China); Deng, L.; Nie, K.; Wang, F.; Tan, T. [Beijing Bioprocess Key Laboratory, College of Life Science and Technology, Beijing University of Chemical Technology, Beijing (China)

2012-12-15

The stability of the immobilized lipase from Candida sp. 99-125 during biodiesel production was investigated. The lipase was separately incubated in the presence of various reaction components such as soybean oil, oleic acid methyl ester, n-hexane, water, methanol, and glycerol, or the lipase was stored at 60, 80, 100 and 120 C. Thereafter the residual lipase activity was determined by methanolysis reaction. The results showed that the lipase was rather stable in the reaction media, except for methanol and glycerol. The stability study performed in a reciprocal shaker indicated that enzyme desorption from the immobilized lipase mainly contributed to the lipase inactivation in the water system. So the methanol and glycerol contents should be controlled more precisely to avoid lipase inactivation, and the immobilization method should be improved with regard to lipase desorption. (Copyright copyright 2012 WILEY-VCH Verlag GmbH and Co. KGaA, Weinheim)

Subsurface Bio-Immobilization of Plutonium: Experiment and Model Validation Study

International Nuclear Information System (INIS)

Reed, Donald; Rittmann, Bruce

2006-01-01

The goal of this project is to conduct a concurrent experimental and modeling study centered on the interactions of Shewanella algae BrY with plutonium and uranium species and phases. The most important objective of this research is to investigate the long-term stability of bioprecipitated immobilized actinide phases under changing redox conditions in biologically active systems. The long-term stability of bio-immobilized actinides (e.g. by bio-reduction) is a key criteria that defines the utility and effectiveness of a remediation/containment strategy for subsurface actinide contaminants. Plutonium, which is the focus of this project, is the key contaminant of concern at several DOE sites

Disposition of surplus fissile materials via immobilization

International Nuclear Information System (INIS)

Gray, L.W.; Kan, T.; Sutcliffe, W.G.; McKibben, J.M.; Danker, W.

1995-01-01

In the Cold War aftermath, the US and Russia have agreed to large reductions in nuclear weapons. To aid in the selection of long-term management options, the USDOE has undertaken a multifaceted study to select options for storage and disposition of surplus plutonium (Pu). One disposition alternative being considered is immobilization. Immobilization is a process in which surplus Pu would be embedded in a suitable material to produce an appropriate form for ultimate disposal. To arrive at an appropriate form, we first reviewed published information on HLW immobilization technologies to identify forms to be prescreened. Surviving forms were screened using multi-attribute utility analysis to determine promising technologies for Pu immobilization. We further evaluated the most promising immobilization families to identify and seek solutions for chemical, chemical engineering, environmental, safety, and health problems; these problems remain to be solved before we can make technical decisions about the viability of using the forms for long-term disposition of Pu. All data, analyses, and reports are being provided to the DOE Office of Fissile Materials Disposition to support the Record of Decision that is anticipated in Summer of 1996

Efficient protein immobilization on polyethersolfone electrospun nanofibrous membrane via covalent binding for biosensing applications

Energy Technology Data Exchange (ETDEWEB)

Mahmoudifard, Matin [Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Soudi, Sara [Stem Cell Biology Department, Stem Cell Technology Research Center, Tehran (Iran, Islamic Republic of); Department of Immunology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Soleimani, Masoud [Department of Hematology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Hosseinzadeh, Simzar [Nanotechnology and Tissue Engineering Department, Stem Cell Technology Research Center, Tehran (Iran, Islamic Republic of); School of Advanced Medical Technologies, Tehran University of Medical Sciences, Tehran (Iran, Islamic Republic of); Esmaeili, Elaheh [Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Department of Hematology, Faculty of Medical Sciences, Tarbiat Modares University, Tehran (Iran, Islamic Republic of); Vossoughi, Manouchehr, E-mail: vosoughi@sharif.edu [Institute for Nanoscience and Nanotechnology, Sharif University of Technology, Tehran (Iran, Islamic Republic of); Chemical and Petroleum Engineering Department, Sharif University of Technology, Tehran (Iran, Islamic Republic of)

2016-01-01

In this paper we introduce novel strategy for antibody immobilization using high surface area electrospun nanofibrous membrane based on ethyl-3-(3-dimethylaminopropyl)-carbodiimide/N-hydroxysuccinimide (EDC/NHS) coupling chemistry. To present the high performance of proposed biosensors, anti-staphylococcus enterotoxin B (anti-SEB) was used as a model to demonstrate the utility of our proposed system. Polymer solution of polyethersolfone was used to fabricate fine nanofibrous membrane. Moreover, industrial polyvinylidene fluoride membrane and conventional microtiter plate were also used to compare the efficiency of antibody immobilization. Scanning electron microscopy images were taken to study the morphology of the membranes. The surface activation of nanofibrous membrane was done with the help of O{sub 2} plasma. PES nanofibrous membrane with carboxyl functional groups for covalent attachment of antibodies were treated by EDC/NHS coupling agent. The quantity of antibody immobilization was measured by enzyme-linked immuno sorbent assay (ELISA) method. Attenuated total reflectance Fourier transform infrared spectroscopy (ATR-FTIR) spectroscopy was performed to confirm the covalent immobilization of antibody on membrane. Atomic force microscopy, scanning electron microscopy and invert fluorescence microscopy were used to analyze the antibody distribution pattern on solid surfaces. Results show that oxygen plasma treatment effectively increased the amount of antibody immobilization through EDC/NHS coupling chemistry. It was found that the use of nanofibrous membrane causes the improved detection signal of ELISA based biosensors in comparison to the standard assay carried out in the 96-well microtiter plate. This method has the potential to improve the ELISA-based biosensor and we believe that this technique can be used in various biosensing methods. - Highlights: • Introduction of novel strategy for antibody immobilization using high surface area electrospun

Fouling-induced enzyme immobilization for membrane reactors

DEFF Research Database (Denmark)

Luo, Jianquan; Meyer, Anne S.; Jonsson, Gunnar Eigil

2013-01-01

A simple enzyme immobilization method accomplished by promoting membrane fouling formation is proposed. The immobilization method is based on adsorption and entrapment of the enzymes in/on the membrane. To evaluate the concept, two membrane orientations, skin layer facing feed (normal mode......, but the reverse mode allowed for higher enzyme loading and stability, and irreversible fouling (i.e. pore blocking) developed more readily in the support structure than in the skin layer. Compared with an enzymatic membrane reactor (EMR) with free enzymes, the novel EMR with enzymes immobilized in membrane......) and support layer facing feed (reverse mode), were used to immobilize alcohol dehydrogenase (ADH, EC 1.1.1.1) and glutamate dehydrogenase (GDH, EC 1.4.1.3), respectively. The nature of the fouling in each mode was determined by filtration fouling models. The permeate flux was larger in the normal mode...

Drug immobilization of walrus (Odobenus rosmarus)

Science.gov (United States)

DeMaster, D.P.; Faro, J.B.; Estes, J.A.; Taggart, James; Zabel, C.

1981-01-01

Five out of nine walrus (Odobenus rosmarus) were successfully immobilized at Round Island, Alaska, in May of 1978 by combinations of phencyclidine hydrochloride and acepromazine hydrochloride. A crossbow was an effective delivery technique. Walruses that had recently hauled out were more suitable for immobilization than well-rested animals. Care was taken to prevent walruses from overheating or suffocating.

b-GALACTOSIDASE IMMOBILIZATION ON CONTROLLED PORE SILICA

Directory of Open Access Journals (Sweden)

H. C. Trevisan

1997-12-01

Full Text Available The immobilization of b -galactosidase from Kluyveromyces fragilis on controlled pore silica was investigated. Immobilization was performed on amino silica activated with glutaraldehyde and the product was applied to the hydrolysis of lactose of whey. The behaviors of the soluble and immobilized enzyme were compared by using whey and a lactose solution as the substrate. With the aim of optimizing the method, parameters such as the amount of glutaraldehyde and the size of the particles were evaluated by comparing activities and stabilities on batch and continuously fluidized bed reactors

Electron Beam-Induced Immobilization of Laccase on Porous Supports for Waste Water Treatment Applications

Directory of Open Access Journals (Sweden)

Elham Jahangiri

2014-08-01

Full Text Available The versatile oxidase enzyme laccase was immobilized on porous supports such as polymer membranes and cryogels with a view of using such biocatalysts in bioreactors aiming at the degradation of environmental pollutants in wastewater. Besides a large surface area for supporting the biocatalyst, the aforementioned porous systems also offer the possibility for simultaneous filtration applications in wastewater treatment. Herein a “green” water-based, initiator-free, and straightforward route to highly reactive membrane and cryogel-based bioreactors is presented, where laccase was immobilized onto the porous polymer supports using a water-based electron beam-initiated grafting reaction. In a second approach, the laccase redox mediators 2,2'-azino-bis(3-ethylbenzothiazoline-6-sulphonic acid (ABTS and syringaldehyde were cross-linked instead of the enzyme via electron irradiation in a frozen aqueous poly(acrylate mixture in a one pot set-up, yielding a mechanical stable macroporous cryogel with interconnected pores ranging from 10 to 50 µm in size. The membranes as well as the cryogels were characterized regarding their morphology, chemical composition, and catalytic activity. The reactivity towards waste- water pollutants was demonstrated by the degradation of the model compound bisphenol A (BPA. Both membrane- and cryogel-immobilized laccase remained highly active after electron beam irradiation. Apparent specific BPA removal rates were higher for cryogel- than for membrane-immobilized and free laccase, whereas membrane-immobilized laccase was more stable with respect to maintenance of enzymatic activity and prevention of enzyme leakage from the carrier than cryogel-immobilized laccase. Cryogel-immobilized redox mediators remained functional in accelerating the laccase-catalyzed BPA degradation, and especially ABTS was found to act more efficiently in immobilized than in freely dissolved state.

Immobilized yeast in bioreactor for alcohol fermentation

International Nuclear Information System (INIS)

Handy, M.K.; Kim, K.

1986-01-01

Mutant of Saccharomyces cerevisiae was developed using a Co-60 source. Cells were immobilized onto sterile, channeled alumina beads and packed into bioreactor column under controlled temperature. Feedstocks containing substrate and nutrients were fed into the bioreactor at specific rates. Beads with greatest porosity and surface area produced the most ethanol. Factors affecting ethanol productivity included: temperature, pH, flow rate, nutrients and substrate in the feedstock

Immobilization of N-Heterocyclic Carbene Compounds: A Synthetic Perspective.

Science.gov (United States)

Zhong, Rui; Lindhorst, Anja C; Groche, Florian J; Kühn, Fritz E

2017-02-08

Over the course of the past 15 years the success story of N-heterocyclic carbene (NHC) compounds in organic, inorganic, and organometallic chemistry has been extended to another dimension. The immobilization of NHC compounds, undergoing continuous diversification, broadens their range of applications and leads to new solutions for challenges in catalytic and synthetic chemistry. This review intends to present a synthetic toolkit for the immobilization of NHC compounds, giving the reader an overview on synthetic techniques and strategies available in the literature. By individually summarizing and assessing the synthetic steps of the immobilization process, a comprehensive picture of the strategies and methodologies for the immobilization of NHC compounds is presented. Furthermore, the characterization of supported NHC compounds is discussed in detail in order to set up necessary criteria for an in-depth analysis of the immobilized derivatives. Finally, the catalytic applications of immobilized NHC compounds are briefly reviewed to illustrate the practical use of this technique for a broad variety of reaction types.

Insulin action in human thighs after one-legged immobilization

DEFF Research Database (Denmark)

Richter, Erik; Kiens, Bente; Mizuno, M.

1989-01-01

Insulin action was assessed in thighs of five healthy young males who had one knee immobilized for 7 days by a splint. The splint was not worn in bed. Subjects also used crutches to prevent weight bearing of the immobilized leg. Immobilization decreased the activity of citrate synthase and 3-OH......-acyl-CoA-dehydrogenase in the vastus lateralis muscle by 9 and 14%, respectively, and thigh volume by 5%. After 7 days of immobilization, a two-step euglycemic hyperinsulinemic clamp procedure combined with arterial and bilateral femoral venous catheterization was performed. Insulin action on glucose uptake and tyrosine release...... of the thighs at mean plasma insulin concentrations of 67 (clamp step I) and 447 microU/ml (clamp step II) was decreased by immobilization, whereas immobilization did not affect insulin action on thigh exchange of free fatty acids, glycerol, O2, or potassium. Before and during the clamp step I, lactate release...

Does immobilization after arthroscopic rotator cuff repair increase tendon healing? A systematic review and meta-analysis.

Science.gov (United States)

Shen, Chong; Tang, Zhi-Hong; Hu, Jun-Zu; Zou, Guo-Yao; Xiao, Rong-Chi; Yan, Dong-Xue

2014-09-01

To determine whether immobilization after arthroscopic rotator cuff repair improved tendon healing compared with early passive motion. A systematic electronic literature search was conducted to identify randomized controlled trials (RCTs) comparing early passive motion with immobilization after arthroscopic rotator cuff repair. The primary outcome assessed was tendon healing in the repaired cuff. Secondary outcome measures were range of motion (ROM) and American Shoulder and Elbow Surgeons (ASES) shoulder scale, Simple Shoulder Test (SST), Constant, and visual analog scale (VAS) for pain scores. Pooled analyses were performed using a random effects model to obtain summary estimates of treatment effect with 95% confidence intervals. Heterogeneity among included studies was quantified. Three RCTs examining 265 patients were included. Meta-analysis revealed no significant difference in tendon healing in the repaired cuff between the early-motion and immobilization groups. A significant difference in external rotation at 6 months postoperatively favored early motion over immobilization, but no significant difference was observed at 1 year postoperatively. In one study, Constant scores were slightly higher in the early-motion group than in the immobilization group. Two studies found no significant difference in ASES, SST, or VAS score between groups. We found no evidence that immobilization after arthroscopic rotator cuff repair was superior to early-motion rehabilitation in terms of tendon healing or clinical outcome. Patients in the early-motion group may recover ROM more rapidly. Level II; systematic review of levels I and II studies.

Dependence of protein binding capacity of dimethylamino-γ-butyric-acid (DMGABA)-immobilized porous membrane on composition of solvent used for DMGABA immobilization

International Nuclear Information System (INIS)

Iwanade, Akio; Umeno, Daisuke; Saito, Kyoichi; Sugo, Takanobu

2013-01-01

Dimethylamino-γ-butyric acid (DMGABA) as an ampholite was reacted with the epoxy group of the poly-glycidyl methacrylate chain grafted onto the pore surface of a porous hollow-fiber polyethylene membrane by radiation-induced graft polymerization. DMGABA was dissolved in a mixture of dioxane and water at various dioxane volume fractions, defined by dividing the dioxane volume by the total volume. The equilibrium binding capacity (EBC) of the DMGABA-immobilized porous hollow-fiber membrane for lysozyme was evaluated in the permeation mode. The EBC was varied from a 1/50-fold monolayer binding capacity to a 10-fold monolayer binding capacity by controlling the composition of the solvent used for DMGABA immobilization and the molar conversion of the epoxy group into the DMGABA group. - Highlights: ► A DMGABA membrane was immobilized by irradiation induced graft polymerization. ► The DMGABA was immobilized in a mixture of dioxane and water of various compositions. ► Lysozyme adsorptivity of DMGABA-immobilized membranes evaluated in the permeation mode. ► The composition of the DMGABA immobilized solvent can control adsorptivity

Preparation of immobilized growing cells and enzymatic hydrolysis of sawdust

International Nuclear Information System (INIS)

Kumakura, M.; Kaetsu, I.

1984-01-01

Trichoderma reesei cells were immobilized by radiation polymerization using porous materials such as non-woven material and sawdust, and the enzymatic hydrolysis of sawdust with the enzyme solution from the immobilized growing cells was studied. The filter paper activity, which shows the magnitude of cellulase production in the immobilized cells, was comparable with that in the intact cells. The filter paper activity was affected by addition concentration of monomer and porous materials. The cells in the immobilized cells grew to be adhered on the surface of the fibrous polymers. Sawdust, which was pretreated by irradiation technique, was effectively hydrolyzed with the enzyme solution resulting from the culture of the immobilized cells, in which the glucose yield increased increasing the culture time of the immobilized cells. (author)

A noble technique a using force-sensing resistor for immobilization-device quality assurance: A feasibility study

Science.gov (United States)

Cho, Min-Seok; Kim, Tae-Ho; Kang, Seong-Hee; Kim, Dong-Su; Kim, Kyeong-Hyeon; Shin, Dong-Seok; Noh, Yu-Yun; Koo, Hyun-Jae; Cheon, Geum Seong; Suh, Tae Suk; Kim, Siyong

2016-03-01

Many studies have reported that a patient can move even when an immobilization device is used. Researchers have developed an immobilization-device quality-assurance (QA) system that evaluates the validity of immobilization devices. The QA system consists of force-sensing-resistor (FSR) sensor units, an electric circuit, a signal conditioning device, and a control personal computer (PC) with in-house software. The QA system is designed to measure the force between an immobilization device and a patient's skin by using the FSR sensor unit. This preliminary study aimed to evaluate the feasibility of using the QA system in radiation-exposure situations. When the FSR sensor unit was irradiated with a computed tomography (CT) beam and a treatment beam from a linear accelerator (LINAC), the stability of the output signal, the image artifact on the CT image, and changing the variation on the patient's dose were tested. The results of this study demonstrate that this system is promising in that it performed within the error range (signal variation on CT beam < 0.30 kPa, root-mean-square error (RMSE) of the two CT images according to presence or absence of the FSR sensor unit < 15 HU, signal variation on the treatment beam < 0.15 kPa, and dose difference between the presence and the absence of the FSR sensor unit < 0.02%). Based on the obtained results, we will volunteer tests to investigate the clinical feasibility of the QA system.

Immobilization of molecular catalysts in supported ionic liquid phases.

Science.gov (United States)

Van Doorslaer, Charlie; Wahlen, Joos; Mertens, Pascal; Binnemans, Koen; De Vos, Dirk

2010-09-28

In a supported ionic liquid phase (SILP) catalyst system, an ionic liquid (IL) film is immobilized on a high-surface area porous solid and a homogeneous catalyst is dissolved in this supported IL layer, thereby combining the attractive features of homogeneous catalysts with the benefits of heterogeneous catalysts. In this review reliable strategies for the immobilization of molecular catalysts in SILPs are surveyed. In the first part, general aspects concerning the application of SILP catalysts are presented, focusing on the type of catalyst, support, ionic liquid and reaction conditions. Secondly, organic reactions in which SILP technology is applied to improve the performance of homogeneous transition-metal catalysts are presented: hydroformylation, metathesis reactions, carbonylation, hydrogenation, hydroamination, coupling reactions and asymmetric reactions.

Change in blood glucose level in rats after immobilization

Science.gov (United States)

Platonov, R. D.; Baskakova, G. M.; Chepurnov, S. A.

1981-01-01

Experiments were carried out on male white rats divided into four groups. In group one the blood glucose level was determined immediately after immobilization. In the other three groups, two hours following immobilization, the blood glucose level was determined every 20 minutes for 3 hours 40 minutes by the glucose oxidase method. Preliminary immobilization for 2 hours removed the increase in the blood glucose caused by the stress reaction. By the 2nd hour of immobilization in the presence of continuing stress, the blood glucose level stabilized and varied within 42 + or - 5.5 and 47 + or - 8.1 mg %. Within 2 hours after the immobilization, the differences in the blood glucose level of the rats from the control groups were statistically insignificant.

Screening of supports for immobilization of commercial porcine pancreatic lipase

Directory of Open Access Journals (Sweden)

Robison Scherer

2011-12-01

Full Text Available The aim of this work is to report the performance of different supports for the immobilization of commercial porcine pancreatic lipase. The immobilization tests were carried out in several types of Accurel, activated alumina, kaolin, montmorillonite, ion exchange resins and zeolites. The characterization of the supports showed differences in terms of specific area and morphology. The characteristics of the supports influenced the amount of enzyme adsorbed, yield of immobilization and esterification activity of the resulting immobilized catalyst. The clays KSF and natural and pillared montmorillonites presented potential for use as support for lipase immobilization in terms of yield and esterification activity. Yields of immobilization of 76.32 and 52.01% were achieved for clays KSF and natural montmorillonite, respectively. Esterification activities of 754.03, 595.51, 591.88 and 515.71 U.g-1 were obtained for lipases immobilized in Accurel MP-100, Amberlite XAD-2, mordenite and pillared montmorillonite, respectively.

Immobilization of tritiated waste-water by hydraulic cements. A survey of the state-of-the-art

International Nuclear Information System (INIS)

Mannone, F.

1987-01-01

An experimental research programme including as one of its major items the definition of a strategy for tritiated waste management is being prepared at the JRC-Ispra. Laboratory work will be performed in ETHEL, the European Tritium Handling Experimental Laboratory under construction at Ispra. To provide background information needed for defining items and planning the execution of such activities, a survey of the state of the art and R and D performed in the field of tritiated water immobilization by hydraulic cements and ultimate packaging by multiple containment systems has been carried out. Particular attention has been focused on results of tritium leach test programmes performed at various USA laboratories in order to verify the leach resistance properties of some tritium immobilization and containment options. Problems and draw backs associated with such options are discussed. Final conclusions are presented. 49 refs

Purification-Free, Target-Selective Immobilization of a Protein from Cell Lysates.

Science.gov (United States)

Cha, Jaehyun; Kwon, Inchan

2018-02-27

Protein immobilization has been widely used for laboratory experiments and industrial processes. Preparation of a recombinant protein for immobilization usually requires laborious and expensive purification steps. Here, a novel purification-free, target-selective immobilization technique of a protein from cell lysates is reported. Purification steps are skipped by immobilizing a target protein containing a clickable non-natural amino acid (p-azidophenylalanine) in cell lysates onto alkyne-functionalized solid supports via bioorthogonal azide-alkyne cycloaddition. In order to achieve a target protein-selective immobilization, p-azidophenylalanine was introduced into an exogenous target protein, but not into endogenous non-target proteins using host cells with amber codon-free genomic DNAs. Immobilization of superfolder fluorescent protein (sfGFP) from cell lysates is as efficient as that of the purified sfGFP. Using two fluorescent proteins (sfGFP and mCherry), the authors also demonstrated that the target proteins are immobilized with a minimal immobilization of non-target proteins (target-selective immobilization). © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Cellulase immobilization on superparamagnetic nanoparticles for reuse in cellulosic biomass conversion

Directory of Open Access Journals (Sweden)

Fernando Segato

2016-07-01

Full Text Available Current cellulosic biomass hydrolysis is based on the one-time use of cellulases. Cellulases immobilized on magnetic nanocarriers offer the advantages of magnetic separation and repeated use for continuous hydrolysis. Most immobilization methods focus on only one type of cellulase. Here, we report co-immobilization of two types of cellulases, β-glucosidase A (BglA and cellobiohydrolase D (CelD, on sub-20 nm superparamagnetic nanoparticles. The nanoparticles demonstrated 100% immobilization efficiency for both BglA and CelD. The total enzyme activities of immobilized BglA and CelD were up to 67.1% and 41.5% of that of the free cellulases, respectively. The immobilized BglA and CelD each retained about 85% and 43% of the initial immobilized enzyme activities after being recycled 3 and 10 times, respectively. The effects of pH and temperature on the immobilized cellulases were also investigated. Co-immobilization of BglA and CelD on MNPs is a promising strategy to promote synergistic action of cellulases while lowering enzyme consumption.

Optimization of Adsorptive Immobilization of Alcohol Dehydrogenases

NARCIS (Netherlands)

Trivedi, Archana; Heinemann, Matthias; Spiess, Antje C.; Daussmann, Thomas; Büchs, Jochen

2005-01-01

In this work, a systematic examination of various parameters of adsorptive immobilization of alcohol dehydrogenases (ADHs) on solid support is performed and the impact of these parameters on immobilization efficiency is studied. Depending on the source of the enzymes, these parameters differently

Fungal laccase: copper induction, semi-purification, immobilization ...

African Journals Online (AJOL)

Fungal laccase: copper induction, semi-purification, immobilization, phenolic effluent treatment and electrochemical measurement. ... In order to apply in an effluent treatment, laccase was immobilized on different vitroceramics supports, pyrolytic graphite and also on a carbon fiber electrode as biosensor. The maximum ...

Strong and Reversible Monovalent Supramolecular Protein Immobilization

NARCIS (Netherlands)

Young, Jacqui F.; Nguyen, Hoang D.; Yang, Lanti; Huskens, Jurriaan; Jonkheijm, Pascal; Brunsveld, Luc

2010-01-01

Proteins with an iron clasp: Site-selective incorporation of a ferrocene molecule into a protein allows for easy, strong, and reversible supramolecular protein immobilization through a selective monovalent interaction of the ferrocene with a cucurbit[7]uril immobilized on a gold surface. The

Increase in stability of cellulase immobilized on functionalized magnetic nanospheres

Energy Technology Data Exchange (ETDEWEB)

Zhang, Wenjuan [Department of Machine Intelligence and Systems Engineering, Faculty of Systems Engineering, Akita Prefectural University, Akita 015-0055 (Japan); Qiu, Jianhui, E-mail: qiu@akita-pu.ac.jp [Department of Machine Intelligence and Systems Engineering, Faculty of Systems Engineering, Akita Prefectural University, Akita 015-0055 (Japan); Feng, Huixia [College of Petrochemical Engineering, Lanzhou University of Technology, Lanzhou 730050 (China); Zang, Limin; Sakai, Eiichi [Department of Machine Intelligence and Systems Engineering, Faculty of Systems Engineering, Akita Prefectural University, Akita 015-0055 (Japan)

2015-02-01

Functionalized magnetic nanospheres were prepared by co-condensation of tetraethylorthosilicate with three different amino-silanes: 3-(2-aminoethylamino propyl)-triethoxysilane (AEAPTES), 3-(2-aminoethylamino propyl)-trimethoxysilane (AEAPTMES) and 3-aminopropyltriethoxysilane (APTES). Then three functionalized magnetic nanospheres were used as supports for immobilization of cellulase. The three functionalized magnetic nanospheres with core–shell morphologies exhibited higher capacity for cellulase immobilization than unfunctionalized magnetic nanospheres. The increasing of surface charge of functionalized magnetic nanospheres leads to an enhancement of the capacity of cellulase immobilization. Particularly, AEAPTMES with methoxy groups was favored to be hydrolyzed and grafted on unfunctionalized magnetic nanospheres than the others. AEAPTMES functionalized magnetic nanospheres with the highest zeta potential (29 mV) exhibited 87% activity recovery and the maximum amount of immobilized cellulase was 112 mg/g support at concentration of initial cellulase of 8 mg/mL. Immobilized cellulase on AEAPTMES functionalized magnetic nanospheres had higher temperature stability and broader pH stability than other immobilized cellulases and free cellulase. In particular, it can be used in about 40 °C, demonstrating the potential of biofuel production using this immobilized cellulase. - Highlights: • Three Amino-silane modified magnetic nanospheres were prepared. • Cellulase immobilized AEAPTMES functionalized magnetic nanospheres had higher temperature stability and broader pH stability than free cellulase. • The potential of biofuel production using this immobilized cellulase.

Increase in stability of cellulase immobilized on functionalized magnetic nanospheres

International Nuclear Information System (INIS)

Zhang, Wenjuan; Qiu, Jianhui; Feng, Huixia; Zang, Limin; Sakai, Eiichi

2015-01-01

Functionalized magnetic nanospheres were prepared by co-condensation of tetraethylorthosilicate with three different amino-silanes: 3-(2-aminoethylamino propyl)-triethoxysilane (AEAPTES), 3-(2-aminoethylamino propyl)-trimethoxysilane (AEAPTMES) and 3-aminopropyltriethoxysilane (APTES). Then three functionalized magnetic nanospheres were used as supports for immobilization of cellulase. The three functionalized magnetic nanospheres with core–shell morphologies exhibited higher capacity for cellulase immobilization than unfunctionalized magnetic nanospheres. The increasing of surface charge of functionalized magnetic nanospheres leads to an enhancement of the capacity of cellulase immobilization. Particularly, AEAPTMES with methoxy groups was favored to be hydrolyzed and grafted on unfunctionalized magnetic nanospheres than the others. AEAPTMES functionalized magnetic nanospheres with the highest zeta potential (29 mV) exhibited 87% activity recovery and the maximum amount of immobilized cellulase was 112 mg/g support at concentration of initial cellulase of 8 mg/mL. Immobilized cellulase on AEAPTMES functionalized magnetic nanospheres had higher temperature stability and broader pH stability than other immobilized cellulases and free cellulase. In particular, it can be used in about 40 °C, demonstrating the potential of biofuel production using this immobilized cellulase. - Highlights: • Three Amino-silane modified magnetic nanospheres were prepared. • Cellulase immobilized AEAPTMES functionalized magnetic nanospheres had higher temperature stability and broader pH stability than free cellulase. • The potential of biofuel production using this immobilized cellulase

Immobilization of lipases on alkyl silane modified magnetic nanoparticles: effect of alkyl chain length on enzyme activity.

Directory of Open Access Journals (Sweden)

Jiqian Wang

Full Text Available BACKGROUND: Biocatalytic processes often require a full recycling of biocatalysts to optimize economic benefits and minimize waste disposal. Immobilization of biocatalysts onto particulate carriers has been widely explored as an option to meet these requirements. However, surface properties often affect the amount of biocatalysts immobilized, their bioactivity and stability, hampering their wide applications. The aim of this work is to explore how immobilization of lipases onto magnetite nanoparticles affects their biocatalytic performance under carefully controlled surface modification. METHODOLOGY/PRINCIPAL FINDINGS: Magnetite nanoparticles, prepared through a co-precipitation method, were coated with alkyl silanes of different alkyl chain lengths to modulate their surface hydrophobicity. Candida rugosa lipase was then directly immobilized onto the modified nanoparticles through hydrophobic interaction. Enzyme activity was assessed by catalytic hydrolysis of p-nitrophenyl acetate. The activity of immobilized lipases was found to increase with increasing chain length of the alkyl silane. Furthermore, the catalytic activities of lipases immobilized on trimethoxyl octadecyl silane (C18 modified Fe(3O(4 were a factor of 2 or more than the values reported from other surface immobilized systems. After 7 recycles, the activities of the lipases immobilized on C18 modified nanoparticles retained 65%, indicating significant enhancement of stability as well through hydrophobic interaction. Lipase immobilized magnetic nanoparticles facilitated easy separation and recycling with high activity retaining. CONCLUSIONS/SIGNIFICANCE: The activity of immobilized lipases increased with increasing alkyl chain length of the alkyl trimethoxy silanes used in the surface modification of magnetite nanoparticles. Lipase stability was also improved through hydrophobic interaction. Alkyl silane modified magnetite nanoparticles are thus highly attractive carriers for

Immobilization of lipases on alkyl silane modified magnetic nanoparticles: effect of alkyl chain length on enzyme activity.

Science.gov (United States)

Wang, Jiqian; Meng, Gang; Tao, Kai; Feng, Min; Zhao, Xiubo; Li, Zhen; Xu, Hai; Xia, Daohong; Lu, Jian R

2012-01-01

Biocatalytic processes often require a full recycling of biocatalysts to optimize economic benefits and minimize waste disposal. Immobilization of biocatalysts onto particulate carriers has been widely explored as an option to meet these requirements. However, surface properties often affect the amount of biocatalysts immobilized, their bioactivity and stability, hampering their wide applications. The aim of this work is to explore how immobilization of lipases onto magnetite nanoparticles affects their biocatalytic performance under carefully controlled surface modification. Magnetite nanoparticles, prepared through a co-precipitation method, were coated with alkyl silanes of different alkyl chain lengths to modulate their surface hydrophobicity. Candida rugosa lipase was then directly immobilized onto the modified nanoparticles through hydrophobic interaction. Enzyme activity was assessed by catalytic hydrolysis of p-nitrophenyl acetate. The activity of immobilized lipases was found to increase with increasing chain length of the alkyl silane. Furthermore, the catalytic activities of lipases immobilized on trimethoxyl octadecyl silane (C18) modified Fe(3)O(4) were a factor of 2 or more than the values reported from other surface immobilized systems. After 7 recycles, the activities of the lipases immobilized on C18 modified nanoparticles retained 65%, indicating significant enhancement of stability as well through hydrophobic interaction. Lipase immobilized magnetic nanoparticles facilitated easy separation and recycling with high activity retaining. The activity of immobilized lipases increased with increasing alkyl chain length of the alkyl trimethoxy silanes used in the surface modification of magnetite nanoparticles. Lipase stability was also improved through hydrophobic interaction. Alkyl silane modified magnetite nanoparticles are thus highly attractive carriers for enzyme immobilization enabling efficient enzyme recovery and recycling.

Ethanol fermentation by immobilized cells of Zymomonas mobilis

Energy Technology Data Exchange (ETDEWEB)

Grote, W.

1985-01-01

Previous studies have shown that immobilized yeast cell cultures have commercial potential for fuel ethanol production. In this study the suitability of strains of Z. mobilis for whole cell immobilization was investigated. Experiments revealed that immobilization in Ca-alginate or K-carrageenan gel or use of flocculating strains was effective for ethanol production at relatively high productivities. Two laboratory size reactors were designed and constructed. These were a compartmented multiple discshaft column and a tower fermentor. Results of this work supported other studies that established that growth and fermentation could be uncoupled. The data indicated that specific metabolic rates were dependent on the nature of the fermentation media. The addition of lactobacilli to Z. mobilis continuous fermentations had only a transient effect, and was unlikely to affect an immobilized Z. mobilis process. With 150 gl/sup -1/ glucose media and a Z. mobilis ZM4 immobilized cell reactor, a maximum volumetric ethanol productivity of 55 gl/sup -1/h/sup -1/ was obtained. The fermentation of sucrose media or sucrose-based raw materials (molasses, cane juice, synthetic mill liquor) by immobilized Z. mobilis ZM4 revealed a pattern of rapid sucrose hydrolysis, preferential glucose utilization and the conversion of fructose to the undesirable by-products levan and sorbitol.

Characterization of a frozen shoulder model using immobilization in rats.

Science.gov (United States)

Kim, Du Hwan; Lee, Kil-Ho; Lho, Yun-Mee; Ha, Eunyoung; Hwang, Ilseon; Song, Kwang-Soon; Cho, Chul-Hyun

2016-12-08

The objective of this study was to investigate serial changes for histology of joint capsule and range of motion of the glenohumeral joint after immobilization in rats. We hypothesized that a rat shoulder contracture model using immobilization would be capable of producing effects on the glenohumeral joint similar to those seen in patients with frozen shoulder. Sixty-four Sprague-Dawley rats were randomly divided into one control group (n = 8) and seven immobilization groups (n = 8 per group) that were immobilized with molding plaster for 3 days, or for 1, 2, 3, 4, 5, or 6 weeks. At each time point, eight rats were euthanized for histologic evaluation of the axillary recess and for measurement of the abduction angle. Infiltration of inflammatory cells was found in the synovial tissue until 2 weeks after immobilization. However, inflammatory cells were diminished and fibrosis was dominantly observed in the synovium and subsynovial tissue 3 weeks after immobilization. From 1 week after immobilization, the abduction angle of all immobilization groups at each time point was significantly lower than that of the control group. Our study demonstrated that a rat frozen shoulder model using immobilization generates the pathophysiologic process of inflammation leading to fibrosis on the glenohumeral joint similar to that seen in patients with frozen shoulder. This model was attained within 3 weeks after immobilization. It may serve as a useful tool to investigate pathogenesis at the molecular level and identify potential target genes that are involved in the development of frozen shoulder.

A simple and robust approach to immobilization of antibody fragments.

Science.gov (United States)

Ikonomova, Svetlana P; He, Ziming; Karlsson, Amy J

2016-08-01

Antibody fragments, such as the single-chain variable fragment (scFv), have much potential in research and diagnostics because of their antigen-binding ability similar to a full-sized antibody and their ease of production in microorganisms. Some applications of antibody fragments require immobilization on a surface, and we have established a simple immobilization method that is based on the biotin-streptavidin interaction and does not require a separate purification step. We genetically fused two biotinylation tags-the biotin carboxyl carrier protein (BCCP) or the AviTag minimal sequence-to six different scFvs (scFv13R4, scFvD10, scFv26-10, scFv3, scFv5, and scFv12) for site-specific biotinylation in vivo by endogenous biotin ligases produced by Escherichia coli. The biotinylated scFvs were immobilized onto streptavidin-coated plates directly from cell lysates, and immobilization was detected through enzyme-linked immunosorbent assays. All scFvs fusions were successfully immobilized, and scFvs biotinylated via the BCCP tag tended to immobilize better than those biotinylated via the AviTag, even when biotinylation efficiency was improved with the biotin ligase BirA. The ability of immobilized scFvs to bind antigens was confirmed using scFv13R4 and scFvD10 with their respective targets β-galactosidase and bacteriophage lambda head protein D (gpD). The immobilized scFv13R4 bound to β-galactosidase at the same level for both biotinylation tags when the surface was saturated with the scFv, and immobilized scFvs retained their functionality for at least 100days after immobilization. The simplicity and robustness of our method make it a promising approach for future applications that require antibody fragment immobilization. Copyright © 2016 Elsevier B.V. All rights reserved.

Continuous production of ethanol from hexoses and pentoses using immobilized mixed cultures of Escherichia coli strains

Science.gov (United States)

Unrean, Pornkamol; Srienc, Friedrich

2010-01-01

We have developed highly efficient ethanologenic E. coli strains that selectively consume pentoses and/or hexoses. Mixed cultures of these strains can be used to selectively adjust the sugar utilization kinetics in ethanol fermentations. Based on the kinetics of sugar utilization, we have designed and implemented an immobilized cell system for the optimized continuous conversion of sugars into ethanol. The results confirm that immobilized mixed cultures support a simultaneous conversion of hexoses and pentoses into ethanol at high yield and at a faster rate than immobilized homogenous cells. Continuous ethanol production has been maintained for several weeks at high productivity with near complete sugar utilization. The control of sugar utilization using immobilized mixed cultures can be adapted to any composition of hexoses and pentoses by adjusting the strain distribution of immobilized cells. The approach, therefore, holds promise for ethanol fermentation from lignocellulosic hydrolysates where the feedstock varies in sugar composition. PMID:20699108

Immobilization of bromelain protease on PVA gels for the oligopeptides synthesis

International Nuclear Information System (INIS)

Fagundes, Fabio P.; Madruga, Liszt Y.C.; Balaban, Rosangela de C.; Costa, Marta

2015-01-01

Enzymatic synthesis of peptides using proteases has attracted a great deal of attention in recent years. One key challenge in peptide synthesis is to find supports for protease immobilization capable of working in aqueous medium at high performance, producing water-soluble oligopeptides. Therefore, the aim of this paper was to immobilize the bromelain protease by Freezing / thawing method on polymeric gels of Poli (vinyl alcohol) in order to produce water-soluble oligopeptides derived from lysine. Calculations of oligolysine yield and average degree of polymerization (DPavg) were monitored by 1 H-NMR analysis. Scanning Electronic Micrograph (SEM) was responsible to associate to the porous size with performance of each system during the production of oligopeptides from lysine. These systems produced oligomers in only 1 hour with DPavg higher than free bromelain. (author)

Immobilization and encapsulation during vitrification of incineration ashes in a coke bed furnace

International Nuclear Information System (INIS)

Kuo, Y.-M.; Lin, T.-C.; Tsai, P.-J.

2006-01-01

A real-scale coke bed furnace system has been successfully applied to vitrify the incineration ashes into glassy slags. The object of this research was to evaluate the effect of the system on the immobilization of metal species in the slag. Ashes and slag specimens were tested to identify their metal phase distribution following a sequential extraction procedure. The mobility of Al, Ca, Cd, Cr, Mg, Mn and Pb was noticeably reduced by vitrification. An important implication is the reduction of Cr 6+ to Cr 3+ along with its immobilization with this coke bed furnace. The Ni and Zn contents were relatively low in slag, indicating that their availability of mobile phases in ashes was reduced during vitrification. The XRD analyses identified the major crystalline phase in slag as akermanite, which is inert and helpful in metal immobilization. The phase distribution analysis also contributed to verify that the incorporation of Ca and Mg enhanced the encapsulation in the slag matrix. The low oxygen content in slag made the structure of silicate resistant to the proton-promoted attack and also enhanced the mobility reduction of matrix elements (Ca, Mg and Al) in the moderately reducible phase and also contributed to the immobilization of other metal species. However, the properties of slag also deserve further studies to ensure its long-term stability and safety

Description of processes for the immobilization of selected transuranic wastes

International Nuclear Information System (INIS)

Timmerman, C.L.

1980-12-01

Processed sludge and incinerator-ash wastes contaminated with transuranic (TRU) elements may require immobilization to prevent the release of these elements to the environment. As part of the TRU Waste Immobilization Program sponsored by the Department of Energy (DOE), the Pacific Northwest Laboratory is developing applicable waste-form and processing technology that may meet this need. This report defines and describes processes that are capable of immobilizing a selected TRU waste-stream consisting of a blend of three parts process sludge and one part incinerator ash. These selected waste streams are based on the compositions and generation rates of the waste processing and incineration facility at the Rocky Flats Plant. The specific waste forms that could be produced by the described processes include: in-can melted borosilicate-glass monolith; joule-heated melter borosilicate-glass monolith or marble; joule-heated melter aluminosilicate-glass monolith or marble; joule-heated melter basaltic-glass monolith or marble; joule-heated melter glass-ceramic monolith; cast-cement monolith; pressed-cement pellet; and cold-pressed sintered-ceramic pellet

Immobilization of Peroxidase onto Magnetite Modified Polyaniline

Directory of Open Access Journals (Sweden)

Eduardo Fernandes Barbosa

2012-01-01

Full Text Available The present study describes the immobilization of horseradish peroxidase (HRP on magnetite-modified polyaniline (PANImG activated with glutaraldehyde. After the optimization of the methodology, the immobilization of HRP on PANImG produced the same yield (25% obtained for PANIG with an efficiency of 100% (active protein. The optimum pH for immobilization was displaced by the effect of the partition of protons produced in the microenvironment by the magnetite. The tests of repeated use have shown that PANImG-HRP can be used for 13 cycles with maintenance of 50% of the initial activity.

Immobilization of cellulase using porous polymer matrix

International Nuclear Information System (INIS)

Kumakura, M.; Kaetsu, I.

1984-01-01

A new method is discussed for the immobilization of cellulase using porous polymer matrices, which were obtained by radiation polymerization of hydrophilic monomers. In this method, the immobilized enzyme matrix was prepared by enzyme absorbtion in the porous polymer matrix and drying treatment. The enzyme activity of the immobilized enzyme matrix varied with monomer concentration, cooling rate of the monomer solution, and hydrophilicity of the polymer matrix, takinn the change of the nature of the porous structure in the polymer matrix. The leakage of the enzymes from the polymer matrix was not observed in the repeated batch enzyme reactions

Process arrangement options for Defense waste immobilization

International Nuclear Information System (INIS)

1980-02-01

Current plans are to immobilize the SRP high-level liquid wastes in a high integrity form. Borosilicate glass was selected in 1977 as the reference waste form and a mjaor effort is currently underway to develop the required technology. A large new facility, referred to as the Defense Waste Processing Facility (DWPF) is being designed to carry out this mission, with project authorization targeted for 1982 and plant startup in 1989. However, a number of other process arrangements or manufacturing strategies, including staging the major elements of the project or using existing SRP facilities for some functions, have been suggested in lieu of building the reference DWPF. This study assesses these various options and compares them on a technical and cost basis with the DWPF. Eleven different manufacturing options for SRP defense waste solidification were examined in detail. These cases are: (1) vitrification of acid waste at current generation rate; (2) vitrification of current rate acid waste and caustic sludge; (3 and 4) vitrification of the sludge portion of neutralized waste; (5) decontamination of salt cake and storage of concentrated cesium and strontium for later immobilization; (6) processing waste in a facility with lower capacity than the DWPF; (7) processing waste in a combination of existing and new facilities; (8) waste immobilization in H Canyon; (9) vitrification of both sludge and salt; (10) DWPF with onsite storage; (11) deferred authorization of DWPF

Immobilization: A Revolution in Traditional Brewing

Science.gov (United States)

Virkajärvi, Ilkka; Linko, Matti

In nature many micro-organisms tend to bind to solid surfaces. This tendency has long been utilized in a number of processes, for example in producing vinegar and acetic acid in bioreactors filled with wood shavings. Acetobacteria are attached to the surface of these shavings. In modern technical language: they are immobilized. Also yeast cells can be immobilized. In the brewing industry this has been the basis for maintaining efficient, continuous fermentation in bioreactors with very high yeast concentrations. The most dramatic change in brewing over recent years has been the replacement of traditional lagering of several weeks by a continuous process in which the residence time is only about 2h. Continuous primary fermentation is used on a commercial scale in New Zealand. In this process, instead of a carrier, yeast is retained in reactors by returning it partly after separation. In many pilot scale experiments the primary fermentation is shortened from about 1week to 1-2days using immobilized yeast reactors. When using certain genetically modified yeast strains no secondary fermentation is needed, and the total fermentation time in immobilized yeast reactors can therefore be shortened to only 2days.

Short-Term Upper Limb Immobilization Affects Action-Word Understanding

Science.gov (United States)

Bidet-Ildei, Christel; Meugnot, Aurore; Beauprez, Sophie-Anne; Gimenes, Manuel; Toussaint, Lucette

2017-01-01

The present study aimed to investigate whether well-established associations between action and language can be altered by short-term upper limb immobilization. The dominant arm of right-handed participants was immobilized for 24 hours with a rigid splint fixed on the hand and an immobilization vest restraining the shoulder, arm, and forearm. The…

Immobilizing affinity proteins to nitrocellulose: a toolbox for paper-based assay developers.

Science.gov (United States)

Holstein, Carly A; Chevalier, Aaron; Bennett, Steven; Anderson, Caitlin E; Keniston, Karen; Olsen, Cathryn; Li, Bing; Bales, Brian; Moore, David R; Fu, Elain; Baker, David; Yager, Paul

2016-02-01

To enable enhanced paper-based diagnostics with improved detection capabilities, new methods are needed to immobilize affinity reagents to porous substrates, especially for capture molecules other than IgG. To this end, we have developed and characterized three novel methods for immobilizing protein-based affinity reagents to nitrocellulose membranes. We have demonstrated these methods using recombinant affinity proteins for the influenza surface protein hemagglutinin, leveraging the customizability of these recombinant "flu binders" for the design of features for immobilization. The three approaches shown are: (1) covalent attachment of thiolated affinity protein to an epoxide-functionalized nitrocellulose membrane, (2) attachment of biotinylated affinity protein through a nitrocellulose-binding streptavidin anchor protein, and (3) fusion of affinity protein to a novel nitrocellulose-binding anchor protein for direct coupling and immobilization. We also characterized the use of direct adsorption for the flu binders, as a point of comparison and motivation for these novel methods. Finally, we demonstrated that these novel methods can provide improved performance to an influenza hemagglutinin assay, compared to a traditional antibody-based capture system. Taken together, this work advances the toolkit available for the development of next-generation paper-based diagnostics.

Bioremediation of oily contamination by free and immobilized microorganisms on laboratory-scale

International Nuclear Information System (INIS)

Bao, M.; Gong, Y.; Li, Y.; Jiang, G.

2009-01-01

This paper described a component immobilization system formed using sodium alginate and active carbon. Two oil-degrading bacterial strains were then isolated from oil-contaminated water samples from an oilfield in China. The Rhosococcus sp and Bacillus cereus sp bacterial strains were studied in order to determine their growth behaviour in the laboratory. Optimal growth conditions were 35 degrees C with a pH of 8 and salinity levels ranging from 2 to 4 per cent. Optimal degradation conditions were similar to optimal growth conditions. Oil degradation rates of the strains ranged between 34.6 and 45.3 per cent after a period of 5 days. A sodium alginate carrier containing active carbon was then used to optimize the microbial immobilization method. Additional experiments showed that the improved immobilization method degraded between 66.3 and 75 per cent of the standard oil samples after a period of 5 days. It was concluded that the immobilized bacteria acted as a bulking agent to facilitate the transfer of oxygen, nutrition, and metabolism needed for rapid hydrocarbon degradation, and increased biological stability. 12 refs., 3 tabs., 4 figs

The effect of cell immobilization on the antibacterial activity of Lactobacillus reuteri DPC16 cells during passage through a simulated gastrointestinal tract system.

Science.gov (United States)

Zhao, Qian; Maddox, Ian S; Mutukumira, Anthony; Lee, Sung Je; Shu, Quan

2012-10-01

Cell immobilization has the ability to influence the survival and functional characteristics of probiotic bacterial strains in harsh environments. This study investigated the effect of cell immobilization and passage through a simulated gastrointestinal tract (GI) on the antibacterial activity of Lactobacillus reuteri DPC16. Antibacterial activity, reuterin production and diol dehydratase activity were assayed in recovered isolates of L. reuteri that had been immobilized in Ca alginate-skim milk, and incubated in simulated GI fluids. Among all the recovered isolates tested, any that had undergone immobilization followed by immediate recovery of the cells without subsequent incubation in any fluids demonstrated the highest reuterin production, antimicrobial activity and diol dehydratase enzyme activity. L. reuteri DPC16 cells that had been immobilized, incubated in simulated GI fluids, and subsequently recovered from the beads often showed some loss of antimicrobial activity compared to the immobilized cells. The data confirm that the process of immobilization of L. reuteri in Ca alginate-skim milk, rather than the passage through simulated GI fluids, resulted in enhanced antibacterial activity. This is attributed to increased diol dehydratase activity, resulting in increased reuterin production.

Acetylcholinesterase immobilization and characterization, and comparison of the activity of the porous silicon-immobilized enzyme with its free counterpart.

Science.gov (United States)

Saleem, Muhammad; Rafiq, Muhammad; Seo, Sung-Yum; Lee, Ki Hwan

2016-02-02

A successful prescription is presented for acetylcholinesterase physically adsorbed on to a mesoporous silicon surface, with a promising hydrolytic response towards acetylthiocholine iodide. The catalytic behaviour of the immobilized enzyme was assessed by spectrophotometric bioassay using neostigmine methyl sulfate as a standard acetycholinesterase inhibitor. The surface modification was studied through field emission SEM, Fourier transform IR spectroscopy, energy-dispersive X-ray spectroscopy, cathode luminescence and X-ray photoelectron spectroscopy analysis, photoluminescence measurement and spectrophotometric bioassay. The porous silicon-immobilized enzyme not only yielded greater enzyme stability, but also significantly improved the native photoluminescence at room temperature of the bare porous silicon architecture. The results indicated the promising catalytic behaviour of immobilized enzyme compared with that of its free counterpart, with a greater stability, and that it aided reusability and easy separation from the reaction mixture. The porous silicon-immobilized enzyme was found to retain 50% of its activity, promising thermal stability up to 90°C, reusability for up to three cycles, pH stability over a broad pH of 4-9 and a shelf-life of 44 days, with an optimal hydrolytic response towards acetylthiocholine iodide at variable drug concentrations. On the basis of these findings, it was believed that the porous silicon-immobilized enzyme could be exploited as a reusable biocatalyst and for screening of acetylcholinesterase inhibitors from crude plant extracts and synthesized organic compounds. Moreover, the immobilized enzyme could offer a great deal as a viable biocatalyst in bioprocessing for the chemical and pharmaceutical industries, and bioremediation to enhance productivity and robustness. © 2016 Authors.

Technetium Immobilization Forms Literature Survey

Energy Technology Data Exchange (ETDEWEB)

Westsik, Joseph H.; Cantrell, Kirk J.; Serne, R. Jeffrey; Qafoku, Nikolla

2014-05-01

Of the many radionuclides and contaminants in the tank wastes stored at the Hanford site, technetium-99 (99Tc) is one of the most challenging to effectively immobilize in a waste form for ultimate disposal. Within the Hanford Tank Waste Treatment and Immobilization Plant (WTP), the Tc will partition between both the high-level waste (HLW) and low-activity waste (LAW) fractions of the tank waste. The HLW fraction will be converted to a glass waste form in the HLW vitrification facility and the LAW fraction will be converted to another glass waste form in the LAW vitrification facility. In both vitrification facilities, the Tc is incorporated into the glass waste form but a significant fraction of the Tc volatilizes at the high glass-melting temperatures and is captured in the off-gas treatment systems at both facilities. The aqueous off-gas condensate solution containing the volatilized Tc is recycled and is added to the LAW glass melter feed. This recycle process is effective in increasing the loading of Tc in the LAW glass but it also disproportionally increases the sulfur and halides in the LAW melter feed which increases both the amount of LAW glass and either the duration of the LAW vitrification mission or the required supplemental LAW treatment capacity.

Nanoparticles of poly(hydroxybutyrate-co-hydroxyvalerate) as support for the immobilization of Candida antarctica lipase (fraction B)

International Nuclear Information System (INIS)

Fernandes, Ilizandra A.; Nyari, Nadia L.D.; Oliveira, Jose Vladimir de; Oliveira, Debora de; Rigo, Elisandra; Souza, Maria Cristiane M. de; Goncalves, Luciana R.B.; Pergher, Sibele Berenice C.

2014-01-01

This work evaluates the immobilization of Candida antarctica lipase (Fraction B) using poly(hydroxybutyrate-co-hydroxyvalerate) (PHBV) nanoparticles as support. The effects of immobilization time (30-150 min) and pH (5-10) on lipase loading were evaluated. The stability of the immobilized enzyme towards temperature (40, 60, and 80 deg C), reuse and storage (at 4 deg C) were also determined. Furthermore, to assess its potential application in a system of interest, the immobilized lipase was used as a catalyst in the esterification of geraniol with oleic acid. The results indicated a time of 120 minutes and pH of 7 as optimal for immobilization. A 21 hour exposure of the PHBV-lipase derivative to 60 deg C showed a 33% reduction of the initial activity while storage at 4 deg C led to a residual activity (5% of the original activity). The derivative was used without significant loss of activity for 4 successive cycles. The use of the immobilized lipase as a catalyst in the production of geranyl oleate led to about 88% conversion of the initial reactants to products. (author)

A feasible enzymatic process for D-tagatose production by an immobilized thermostable L-arabinose isomerase in a packed-bed bioreactor.

Science.gov (United States)

Kim, Hye-Jung; Ryu, Se-Ah; Kim, Pil; Oh, Deok-Kun

2003-01-01

To develop a feasible enzymatic process for d-tagatose production, a thermostable l-arabinose isomerase, Gali152, was immobilized in alginate, and the galactose isomerization reaction conditions were optimized. The pH and temperature for the maximal galactose isomerization reaction were pH 8.0 and 65 degrees C in the immobilized enzyme system and pH 7.5 and 60 degrees C in the free enzyme system. The presence of manganese ion enhanced galactose isomerization to tagatose in both the free and immobilized enzyme systems. The immobilized enzyme was more stable than the free enzyme at the same pH and temperature. Under stable conditions of pH 8.0 and 60 degrees C, the immobilized enzyme produced 58 g/L of tagatose from 100 g/L galactose in 90 h by batch reaction, whereas the free enzyme produced 37 g/L tagatose due to its lower stability. A packed-bed bioreactor with immobilized Gali152 in alginate beads produced 50 g/L tagatose from 100 g/L galactose in 168 h, with a productivity of 13.3 (g of tagatose)/(L-reactor.h) in continuous mode. The bioreactor produced 230 g/L tagatose from 500 g/L galactose in continuous recycling mode, with a productivity of 9.6 g/(L.h) and a conversion yield of 46%.

Structural and Chemical Characterization of Silica Spheres before and after Modification by Silanization for Trypsin Immobilization

Directory of Open Access Journals (Sweden)

Eduardo F. Barbosa

2017-01-01

Full Text Available In the last decades, silica particles of a variety of sizes and shapes have been characterized and chemically modified for several applications, from chromatographic separation to dental supplies. The present study proposes the use of aminopropyl triethoxysilane (APTS silanized silica particles to immobilize the proteolytic enzyme trypsin for the development of a bioreactor. The major advantage of the process is that it enables the polypeptides hydrolysis interruption simply by removing the silica particles from the reaction bottle. Silanized silica surfaces showed significant morphological changes at micro- and nanoscale level. Chemical characterization showed changes in elemental composition, chemical environment, and thermal degradation. Their application as supports for trypsin immobilization showed high immobilization efficiency at reduced immobilization times, combined with more acidic conditions. Indirect immobilization quantification by reversed-phase ultrafast high performance liquid chromatography proved to be a suitable approach due to its high linearity and sensitivity. Immobilized trypsin activities on nonmodified and silanized silica showed promising features (e.g., selective hydrolysis for applications in proteins/peptides primary structure elucidation for proteomics. Silanized silica system produced some preferential targeting peptides, probably due to the hydrophobicity of the nanoenvironment conditioned by silanization.

Ettringite and C-S-H Portland cement phases for waste ion immobilization: A review

International Nuclear Information System (INIS)

Gougar, M.L.D.; Scheetz, B.E.; Roy, D.M.

1996-01-01

The formation, structure and chemistry of the ettringite and C-S-H phases of Portland cement have been reviewed as they relate to waste ion immobilization. The purpose of this review was to investigate the use of Portland cement as a host for priority metallic pollutants as identified by the Environmental Protection Agency and as a host for radioactive waste ions as identified in 40 CFR 191. Ettringite acts as host to a number of these ions in both the columnar and channel sections of the crystal structure. Substitutions have been made at the calcium, aluminum, hydroxide and sulfate sites. C-S-H also hosts a number of the waste species in both ionic and salt form. Immobilization mechanisms for C-S-H include sorption, phase mixing and substitution. The following ions have not apparently been reported as specifically immobilized by one of these phases: Ag, Am, Np, Pu, Ra, Tc, Th and Sn; however, some of these ions are immobilized by Portland cement

Preliminary assessment of nine waste-form products/processes for immobilizing transuranic wastes

International Nuclear Information System (INIS)

Crisler, L.R.

1980-09-01

Nine waste-form processes for reduction of the present and projected Transuranic (TRU) waste inventory to an immobilized product have been evaluated. Product formulations, selected properties, preparation methods, technology status, problem areas needing resolution and location of current research development being pursued in the United States are discussed for each process. No definitive utility ranking is attempted due to the early stage of product/process development for TRU waste containing products and the uncertainties in the state of current knowledge of TRU waste feed compositional and quantitative makeup. Of the nine waste form products/processes included in this discussion, bitumen and cements (encapsulation agents) demonstrate the degree of flexibility necessary to immobilize the wide composition range present in the TRU waste inventory. A demonstrated process called Slagging Pyrolysis Incineration converts a varied compositional feed (municipal wastes) to a ''basalt'' like product. This process/product appears to have potential for TRU waste immobilization. The remaining waste forms (borosilicate glass, high-silica glass, glass ceramics, ''SYNROC B'' and cermets) have potential for immobilizing a smaller fraction of the TRU waste inventory than the above discussed waste forms

Ethanol production by repeated batch and continuous fermentations of blackstrap molasses using immobilized yeast cells on thin-shell silk cocoons

International Nuclear Information System (INIS)

Rattanapan, Anuchit; Limtong, Savitree; Phisalaphong, Muenduen

2011-01-01

Highlights: → Thin-shell silk cocoons for immobilization of Saccharomycescerevisiae. → Advantages: high mechanical strength, light weight, biocompatibility and high surface area. → Enhanced cell stability and ethanol productivity by the immobilization system. -- Abstract: A thin-shell silk cocoon (TSC), a residual from the silk industry, is used as a support material for the immobilization of Saccharomyces cerevisiae M30 in ethanol fermentation because of its properties such as high mechanical strength, light weight, biocompatibility and high surface area. In batch fermentation with blackstrap molasses as the main fermentation substrate, an optimal ethanol concentration of 98.6 g/L was obtained using a TSC-immobilized cell system at an initial reducing sugar concentration of 240 g/L. The ethanol concentration produced by the immobilized cells was 11.5% higher than that produced by the free cells. Ethanol production in five-cycle repeated batch fermentation demonstrated the enhanced stability of the immobilized yeast cells. Under continuous fermentation in a packed-bed reactor, a maximum ethanol productivity of 19.0 g/(L h) with an ethanol concentration of 52.8 g/L was observed at a 0.36 h -1 dilution rate.

Functional results following fractures of the proximal humerus. A controlled clinical study comparing two periods of immobilization

DEFF Research Database (Denmark)

Kristiansen, B; Angermann, P; Larsen, T K

1989-01-01

In order to compare 1 and 3 weeks of immobilization following proximal humeral fractures a prospective controlled trial was performed in 85 patients. Clinical follow-up according to the Neer assessment system was done after 1, 3, 6, 12, and 24 months. One week of immobilization resulted in a better...

Increase in stability of cellulase immobilized on functionalized magnetic nanospheres

Science.gov (United States)

Zhang, Wenjuan; Qiu, Jianhui; Feng, Huixia; Zang, Limin; Sakai, Eiichi

2015-02-01

Functionalized magnetic nanospheres were prepared by co-condensation of tetraethylorthosilicate with three different amino-silanes: 3-(2-aminoethylamino propyl)-triethoxysilane (AEAPTES), 3-(2-aminoethylamino propyl)-trimethoxysilane (AEAPTMES) and 3-aminopropyltriethoxysilane (APTES). Then three functionalized magnetic nanospheres were used as supports for immobilization of cellulase. The three functionalized magnetic nanospheres with core-shell morphologies exhibited higher capacity for cellulase immobilization than unfunctionalized magnetic nanospheres. The increasing of surface charge of functionalized magnetic nanospheres leads to an enhancement of the capacity of cellulase immobilization. Particularly, AEAPTMES with methoxy groups was favored to be hydrolyzed and grafted on unfunctionalized magnetic nanospheres than the others. AEAPTMES functionalized magnetic nanospheres with the highest zeta potential (29 mV) exhibited 87% activity recovery and the maximum amount of immobilized cellulase was 112 mg/g support at concentration of initial cellulase of 8 mg/mL. Immobilized cellulase on AEAPTMES functionalized magnetic nanospheres had higher temperature stability and broader pH stability than other immobilized cellulases and free cellulase. In particular, it can be used in about 40 °C, demonstrating the potential of biofuel production using this immobilized cellulase.

Visible and UV-curable chitosan derivatives for immobilization of biomolecules.

Science.gov (United States)

Kim, Eun-Hye; Han, Ga-Dug; Kim, Jae-Won; Noh, Seung-Hyun; Lee, Jae-Gwan; Ito, Yoshihiro; Son, Tae-Il

2017-11-01

Chitosan, which has many biocompatible properties, is used widely in medical field like wound healing, drug delivery and so on. Chitosan could be used as a biomaterial to immobilize protein-drug. There are many methods to immobilize protein-drug, but they have some drawbacks such as low efficiency and denaturation of protein. Therefore, photo-immobilization method is suggested to immobilize protein-drug. Photo-immobilization method is simple-reaction and also needs no additional crosslinking reagent. There has been some effort to modify chitosan to have an ability of photo-immobilization. Generally, visible and UV light reactive chitosan derivatives were prepared. Various types of photo-curable chitosan derivatives showed possibility for application to medical field. For example, they showed ability for protein-immobilization and some of them showed wound-healing effect, anti-adhesive effect, or property to interact directly with titanium surface. In this study, we introduce many types of photo-curable chitosan derivative and their possibility of medical application. Copyright © 2017 Elsevier B.V. All rights reserved.

Recent advances in covalent, site-specific protein immobilization [version 1; referees: 3 approved

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Morten Meldal

2016-09-01

Full Text Available The properties of biosensors, biomedical implants, and other materials based on immobilized proteins greatly depend on the method employed to couple the protein molecules to their solid support. Covalent, site-specific immobilization strategies are robust and can provide the level of control that is desired in this kind of application. Recent advances include the use of enzymes, such as sortase A, to couple proteins in a site-specific manner to materials such as microbeads, glass, and hydrogels. Also, self-labeling tags such as the SNAP-tag can be employed. Last but not least, chemical approaches based on bioorthogonal reactions, like the azide–alkyne cycloaddition, have proven to be powerful tools. The lack of comparative studies and quantitative analysis of these immobilization methods hampers the selection process of the optimal strategy for a given application. However, besides immobilization efficiency, the freedom in selecting the site of conjugation and the size of the conjugation tag and the researcher’s expertise regarding molecular biology and/or chemical techniques will be determining factors in this regard.

[Oligonucleotide derivatives in the nucleic acid hybridization analysis. I. Covalent immobilization of oligonucleotide probes onto the nylon].

Science.gov (United States)

Dmitrienko, E V; Pyshnaia, I A; Pyshnyĭ, D V

2010-01-01

The features of UV-induced immobilization of oligonucleotides on a nylon membranes and the effectiveness of enzymatic labeling of immobilized probes at heterophase detection of nucleic acids are studied. Short terminal oligothymidilate (up to 10 nt) sequences are suggested to attach to the probe via a flexible ethylene glycol based linker. The presence of such fragment enhances the intensity of immobilization and reduces UV-dependent degradation of the targeted (sequence-specific) part of the probe by reducing the dose needed for the immobilization of DNA. The optimum dose of UV-irradiation is determined to be ~0.4 J/cm(2) at the wavelength 254 nm. This dose provides high level of hybridization signal for immobilized probes with various nucleotide composition of the sequence specific moiety. The amide groups of the polyamide are shown to play the key role in the photoinduced immobilization of nucleic acids, whereas the primary amino groups in the structure of PA is not the center responsible for the covalent binding of DNA by UV-irradiation, as previously believed. Various additives in the soaking solution during the membrane of UV-dependent immobilization of probes are shown to influence its effectiveness. The use of alternative to UV-irradiation system of radical generation are shown to provide the immobilization of oligonucleotides onto the nylon membrane.

Protic ionic liquid as additive on lipase immobilization using silica sol-gel.

Science.gov (United States)

de Souza, Ranyere Lucena; de Faria, Emanuelle Lima Pache; Figueiredo, Renan Tavares; Freitas, Lisiane dos Santos; Iglesias, Miguel; Mattedi, Silvana; Zanin, Gisella Maria; dos Santos, Onélia Aparecida Andreo; Coutinho, João A P; Lima, Álvaro Silva; Soares, Cleide Mara Faria

2013-03-05

Ionic liquids (ILs) have evolved as a new type of non-aqueous solvents for biocatalysis, mainly due to their unique and tunable physical properties. A number of recent review papers have described a variety of enzymatic reactions conducted in IL solutions, on the other hand, to improve the enzyme's activity and stability in ILs; major methods being explored include the enzyme immobilization (on solid support, sol-gel, etc.), protic ionic liquids used as an additive process. The immobilization of the lipase from Burkholderia cepacia by the sol-gel technique using protic ionic liquids (PIL) as additives to protect against inactivation of the lipase due to release of alcohol and shrinkage of the gel during the sol-gel process was investigated in this study. The influence of various factors such as the length of the alkyl chain of protic ionic liquids (monoethanolamine-based) and a concentration range between 0.5 and 3.0% (w/v) were evaluated. The resulting hydrophobic matrices and immobilized lipases were characterised with regard to specific surface area, adsorption-desorption isotherms, pore volume (V(p)) and size (d(p)) according to nitrogen adsorption and scanning electron microscopy (SEM), physico-chemical properties (thermogravimetric - TG, differential scanning calorimetry - DSC and Fourier transform infrared spectroscopy - FTIR) and the potential for ethyl ester and emulsifier production. The total activity yields (Y(a)) for matrices of immobilized lipase employing protic ionic liquids as additives always resulted in higher values compared with the sample absent the protic ionic liquids, which represents 35-fold increase in recovery of enzymatic activity using the more hydrophobic protic ionic liquids. Compared with arrays of the immobilized biocatalyst without additive, in general, the immobilized biocatalyst in the presence of protic ionic liquids showed increased values of surface area (143-245 m(2) g(-1)) and pore size (19-38 Å). Immobilization with

Implementation of Man-made Tongue Immobilization Devices in Treating Head and Neck Cancer Patients

International Nuclear Information System (INIS)

Baek, Jong Geal; Kim, Joo Ho; Lee, Sang Kyu; Lee, Won Joo; Yoon, Jong Won; Cho, Jeong Hee

2008-01-01

For head and neck cancer patients treated with radiation therapy, proper immobilization of intra-oral structures is crucial in reproducing treatment positions and optimizing dose distribution. We produced a man-made tongue immobilization device for each patient subjected to this study. Reproducibility of treatment positions and dose distributions at air-and-tissue interface were compared using man-made tongue immobilization devices and conventional tongue-bites. Dental alginate and putty were used in producing man-made tongue immobilization devices. In order to evaluate reproducibility of treatment positions, all patients were CT-simulated, and linac-gram was repeated 5 times with each patient in the treatment position. An acrylic phantom was devised in order to evaluate safety of man-made tongue immobilization devices. Air, water, alginate and putty were placed in the phantom and dose distributions at air-and-tissue interface were calculated using Pinnacle (version 7.6c, Phillips, USA) and measured with EBT film. Two different field sizes (33 cm and 55 cm) were used for comparison. Evaluation of linac grams showed reproducibility of a treatment position was 4 times more accurate with man-made tongue immobilization devices compared with conventional tongue bites. Patients felt more comfortable using customized tongue immobilization devices during radiation treatment. Air-and-tissue interface dose distributions calculated using Pinnacle were 7.78% and 0.56% for 33 cm field and 55 cm field respectively. Dose distributions measured with EBT (international specialty products, USA) film were 36.5% and 11.8% for 33 cm field and 55 cm field respectively. Values from EBT film were higher. Using man-made tongue immobilization devices made of dental alginate and putty in treatment of head and neck cancer patients showed higher reproducibility of treatment position compared with using conventional mouth pieces. Man-made immobilization devices can help optimizing air

Implementation of Man-made Tongue Immobilization Devices in Treating Head and Neck Cancer Patients

Energy Technology Data Exchange (ETDEWEB)

Baek, Jong Geal; Kim, Joo Ho; Lee, Sang Kyu; Lee, Won Joo; Yoon, Jong Won; Cho, Jeong Hee [Dept. of Radiation Oncology, Yensei Cancer Center, Yensei University Health System, Seoul (Korea, Republic of)

2008-03-15

For head and neck cancer patients treated with radiation therapy, proper immobilization of intra-oral structures is crucial in reproducing treatment positions and optimizing dose distribution. We produced a man-made tongue immobilization device for each patient subjected to this study. Reproducibility of treatment positions and dose distributions at air-and-tissue interface were compared using man-made tongue immobilization devices and conventional tongue-bites. Dental alginate and putty were used in producing man-made tongue immobilization devices. In order to evaluate reproducibility of treatment positions, all patients were CT-simulated, and linac-gram was repeated 5 times with each patient in the treatment position. An acrylic phantom was devised in order to evaluate safety of man-made tongue immobilization devices. Air, water, alginate and putty were placed in the phantom and dose distributions at air-and-tissue interface were calculated using Pinnacle (version 7.6c, Phillips, USA) and measured with EBT film. Two different field sizes (33 cm and 55 cm) were used for comparison. Evaluation of linac grams showed reproducibility of a treatment position was 4 times more accurate with man-made tongue immobilization devices compared with conventional tongue bites. Patients felt more comfortable using customized tongue immobilization devices during radiation treatment. Air-and-tissue interface dose distributions calculated using Pinnacle were 7.78% and 0.56% for 33 cm field and 55 cm field respectively. Dose distributions measured with EBT (international specialty products, USA) film were 36.5% and 11.8% for 33 cm field and 55 cm field respectively. Values from EBT film were higher. Using man-made tongue immobilization devices made of dental alginate and putty in treatment of head and neck cancer patients showed higher reproducibility of treatment position compared with using conventional mouth pieces. Man-made immobilization devices can help optimizing air

Immobilization of cellulase on functionalized cobalt ferrite nanoparticles

International Nuclear Information System (INIS)

Bohara, Raghvendra Ashok; Thorat, Nanasaheb Devappa; Pawar, Shivaji Hariba

2016-01-01

Amine functionalized cobalt ferrite (AF-CoFe 2 O 4 ) magnetic nanoparticles (MNPs) were used for immobilization of cellulase enzyme via 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDS) and N-hydroxysuccinimide (NHS) coupling reaction. The structural, morphological and magnetic properties of AF-CoFe 2 O 4 were determined. TEM micrograph revealed a mean diameter of -8 nm and showed that the AF-CoFe 2 O 4 remain distinct with no significant change in size after binding with cellulase. Fourier transform infrared (FT-IR) spectroscopy confirmed the binding of cellulase to AF-CoFe 2 O 4 . The properties of immobilized cellulase were investigated by optimizing binding efficiency, pH, temperature and reusability. The results showed that the immobilized cellulase has higher thermal stability than free cellulase, which might be due to covalent interaction between cellulase and AF-CoFe 2 O 4 surface. The immobilized cellulase also showed good reusability after recovery. Therefore, AF-CoFe 2 O 4 MNPs can be considered as promising candidate for enzyme immobilization.

MUCOADHESIVE GEL WITH IMMOBILIZED LYSOZYME: PREPARATION AND PROPERTIES

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Dekina S. S.

2015-08-01

Full Text Available The study of non-covalent immobilized lysozyme, as well as physico-chemical and biochemical properties of obtained mucoadhesive gel was the aim of the research. Lysozyme activity was determined by bacteriolytic method (Micrococcus lysodeikticus cells acetone powder was a substrate. Lysozyme immobilization was conducted by the method of entrapment in gel. Enzyme carrier interaction was studied by viscometric, spectrophotometric and spectrofluorimetric methods. Mucoadhesive gel with immobilized lysozyme, possessing antiinflammatory and antimicrobial activities, was prepared. Due to immobilization, protein-polymer complex with the original enzymatic activity was formed. The product is characterized by high mucoadhesive properties, quantitative retaining of protein and bacteriolytic activity, prolonged release of the enzyme, improved biochemical characteristics (extended pH-activity profile, stability in acidic medium and during storage for 2 years, and it is perspective for further studies. The proposed method for lysozyme immobilization in the carboxymethyl cellulose sodium salt gel allows to obtain a stable, highly efficient product, with high adhesive properties for attachment to the mucous membranes, that is promising for use in biomedicine.

Performance Enhancements to the Hanford Waste Treatment and Immobilization Plant Low-Activity Waste Vitrification System

International Nuclear Information System (INIS)

Hamel, W. F.; Gerdes, K.; Holton, L. K.; Pegg, I.L.; Bowan, B.W.

2006-01-01

The U.S Department of Energy Office of River Protection (DOE-ORP) is constructing a Waste Treatment and Immobilization Plant (WTP) for the treatment and vitrification of underground tank wastes stored at the Hanford Site in Washington State. The WTP comprises four major facilities: a pretreatment facility to separate the tank waste into high level waste (HLW) and low-activity waste (LAW) process streams, a HLW vitrification facility to immobilize the HLW fraction; a LAW vitrification facility to immobilize the LAW fraction, and an analytical laboratory to support the operations of all four treatment facilities. DOE has established strategic objectives to optimize the performance of the WTP facilities and the LAW and HLW waste forms to reduce the overall schedule and cost for treatment and vitrification of the Hanford tank wastes. This strategy has been implemented by establishing performance expectations in the WTP contract for the facilities and waste forms. In addition, DOE, as owner-operator of the WTP facilities, continues to evaluate 1) the design, to determine the potential for performance above the requirements specified in the WTP contract; and 2) improvements in production of the LAW and HLW waste forms. This paper reports recent progress directed at improving production of the LAW waste form. DOE's initial assessment, which is based on the work reported in this paper, is that the treatment rate of the WTP LAW vitrification facility can be increased by a factor of 2 to 4 with a combination of revised glass formulations, modest increases in melter glass operating temperatures, and a second-generation LAW melter with a larger surface area. Implementing these improvements in the LAW waste immobilization capability can benefit the LAW treatment mission by reducing the cost of waste treatment. (authors)

Protein selectivity with immobilized metal ion-tacn sorbents: chromatographic studies with human serum proteins and several other globular proteins.

Science.gov (United States)

Jiang, W; Graham, B; Spiccia, L; Hearn, M T

1998-01-01

The chromatographic selectivity of the immobilized chelate system, 1,4,7-triazocyclononane (tacn), complexed with the borderline metal ions Cu2+, Cr3+, Mn2+, Co2+, Zn2+, and Ni2+ has been investigated with hen egg white lysozyme, horse heart cytochrome c, and horse skeletal muscle myoglobin, as well as proteins present in partially fractionated preparations of human plasma. The effects of ionic strength and pH of the loading and elution buffers on protein selectivities of these new immobilized metal ion affinity chromatographic (IMAC) systems have been examined. The results confirm that immobilized Mn;pl-tacn sorbents exhibit a novel type of IMAC behavior with proteins. In particular, the chromatographic properties of these immobilized M(n+)-tacn ligand systems were significantly different compared to the IMAC behavior observed with other types of immobilized tri- and tetradentate chelating ligands, such as iminodiacetic acid, O-phosphoserine, or nitrilotriacetic acid, when complexed with borderline metal ions. The experimental results have consequently been evaluated in terms of the additional contributions to the interactive processes mediated by effects other than solely the conventional lone pair Lewis soft acid-Lewis soft base coordination interactions, typically found for the IMAC of proteins with borderline and soft metal ions, such as Cu2+ or Ni2+.

Effect of immobilization conditions on the properties of β-galactosidase immobilized in xanthan/chitosan multilayers

International Nuclear Information System (INIS)

Yovcheva, T; Viraneva, A; Bodurov, I; Marudova, M; Vasileva, T; Cholev, D; Bivolarski, V; Iliev, I

2017-01-01

The effect of lactose concentration on the activity of the immobilised enzyme β-galactosidase from Aspergillus niger has been evaluated, considering future applications for the production of galactooligosaccahrides with prebiotic potential. The following enzyme was immobilized in xanthan and chitosan polyelectrolyte multilayers (PEMs) deposited by dip coating method on polylactic acid positively corona charged pads. The pads were charged in a corona discharge system, consisting of a corona electrode (needle), a grounded plate, and a metal grid placed between them. Positive 5 kV voltage was applied to the corona electrode. 1 kV voltage of the same polarity as that of the corona electrode was applied to the grid. The chitosan layers were crosslinked with sodium tripolyphosphate (Na-TPP). The enzyme showed a temperature optimum at 50 °C and a pH optimum at 5.0. The immobilization was carried out over the different adsorption time and optimum conditions were determined. These results give insights for further optimization of transgalactosydase reactions in order to produce galactooligosaccharides with specific structure and having pronounced better prebiotic properties. For the determination of the surface morphology of the investigated samples an atomic force microscope was used and root mean square roughness was obtained. (paper)

Immobilization of cobalt by sulfate-reducing bacteria in subsurface sediments

Science.gov (United States)

Krumholz, Lee R.; Elias, Dwayne A.; Suflita, Joseph M.

2003-01-01

We investigated the impact of sulfate-reduction on immobilization of metals in subsurface aquifers. Co 2+ was used as a model for heavy metals. Factors limiting sulfate-reduction dependent Co 2+ immobilization were tested on pure cultures of sulfate-reducing bacteria, and in sediment columns from a landfill leachate contaminated aquifer. In the presence of 1 mM Co 2+ , the growth of pure cultures of sulfate-reducing bacteria was not impacted. Cultures of Desulfovibrio desulfuricans, Desulfotomaculum gibsoniae , and Desulfomicrobium hypogeia removed greater than 99.99% of the soluble Co 2+ when CoCl 2 was used with no chelators. The above cultures and Desulfoarcula baarsi removed 98-99.94% of the soluble Co(II) when the metal was complexed with the model ligand nitrilotriacetate (Co-NTA). Factors controlling the rate of sulfate-reduction based Co 2+ precipitation were investigated in sediment-cobalt mixtures. Several electron donors were tested and all but toluene accelerated soluble Co 2+ loss. Ethanol and formate showed the greatest stimulation. All complex nitrogen sources tested slowed and decreased the extent of Co 2+ removal from solution relative to formate-amended sediment incubations. A range of pH values were tested (6.35-7.81), with the more alkaline incubations exhibiting the largest precipitation of Co 2+ . The immobilization of Co 2+ in sediments was also investigated with cores to monitor the flow of Co 2+ through undisturbed sediments. An increase in the amount of Co 2+ immobilized as CoS was observed as sulfate reduction activity was stimulated in flow through columns. Both pure culture and sediment incubation data indicate that stimulation of sulfate reduction is a viable strategy in the immobilization of contaminating metals in subsurface systems.

Immobilizing live Escherichia coli for AFM studies of surface dynamics

International Nuclear Information System (INIS)

Lonergan, N.E.; Britt, L.D.; Sullivan, C.J.

2014-01-01

Atomic force microscopy (AFM) is a probe-based technique that permits high resolution imaging of live bacterial cells. However, stably immobilizing cells to withstand the probe-based lateral forces remains an obstacle in AFM mediated studies, especially those of live, rod shaped bacteria in nutrient media. Consequently, AFM has been under-utilized in the research of bacterial surface dynamics. The aim of the current study was to immobilize a less adherent Escherichia coli strain in a method that both facilitates AFM imaging in nutrient broth and preserves overall cell viability. Immobilization reagents and buffers were systematically evaluated and the cell membrane integrity was monitored in all sample preparations. As expected, the biocompatible gelatin coated surfaces facilitated stable cell attachment in lower ionic strength buffers, yet poorly immobilized cells in higher ionic strength buffers. In comparison, poly-L-lysine surfaces bound cells in both low and high ionic strength buffers. The benefit of the poly-L-lysine binding capacity was offset by the compromised membrane integrity exhibited by cells on poly-L-lysine surfaces. However, the addition of divalent cations and glucose to the immobilization buffer was found to mitigate this unfavorable effect. Ultimately, immobilization of E. coli cells on poly-L-lysine surfaces in a lower ionic strength buffer supplemented with Mg 2+ and Ca 2+ was determined to provide optimal cell attachment without compromising the overall cell viability. Cells immobilized in this method were stably imaged in media through multiple division cycles. Furthermore, permeability assays indicated that E. coli cells recover from the hypoosmotic stress caused by immobilization in low ionic strength buffers. Taken together, this data suggests that stable immobilization of viable cells on poly-L-lysine surfaces can be accomplished in lower ionic strength buffers that are supplemented with divalent cations for membrane stabilization while

Photocatalytic Study of New Immobilized TiO2 Technique Towards Degradation of Reactive Red 4 Dye

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Ain S. K.

2016-01-01

Full Text Available The study on TiO2 for wastewater remediation has gained interest among researchers. However, the application of this photocatalyst is limited due to non-recyclability of conventional TiO2. Thus, immobilization technique has been developed to solve this issue. Hence, a comparison study between two types of immobilized photocatalysts namely titanium dioxide (TiO2 and TiO2 mixed with polyvinyl alcohol (PVA has been conducted in this work to observe the significant effect of PVA polymer in photocatalysis reaction of reactive red 4 (RR4 dye. Double sided adhesive tape (DSAT was used as thin layer binder in this immobilization system. The result shows that the photocatalytic performance of TiO2-PVA/DSAT was higher than that of TiO2/DSAT under both normal UV and visible light irradiations due to the conjugated unsaturated polymer from PVA serve as electron donor for TiO2 thus increase the photocatalysis process. Besides, TiO2-PVA/DSAT was also found to possess much better adhesion strength to the support material compared to TiO2/DSAT. Based on the findings, this TiO2 immobilization system is expected to be beneficial in the industrial wastewater treatment. Thus, further study to improve the photocatalytic activity of this immobilized TiO2 will be in our future work.

Computer-aided design of bromelain and papain covalent immobilization

OpenAIRE

Cutiño-Avila, Bessy; Gil Pradas, Dayrom; Aragón Abreu, Carlos; Fernández Marrero, Yuniel; Hernández de la Torre, Martha; Salas Sarduy, Emir; Chávez Planes, María de los Ángeles; Guisán Seijas, José Manuel; Díaz Brito, Joaquín; del Monte-Martínez, Alberto

2014-01-01

Enzymes as immobilized derivatives have been widely used in Food, Agrochemical, Pharmaceutical and Biotechnological industries. Protein immobilization is probably the most used technology to improve the operational stability of these molecules. Bromelain (Ananas comosus) and papain (Carica papaya) are cystein proteases extensively used as immobilized biocatalyst with several applications in therapeutics, racemic mixtures resolution, affinity chromatography and others industrial scenarios. The...

Dosimetric effects of immobilization devices on SABR for lung cancer using VMAT technique.

Science.gov (United States)

Park, Jong In; Ye, Sung-Joon; Kim, Hak Jae; Park, Jong Min

2015-01-08

The purpose of this study was to investigate the dosimetric effects of immobilization devices on the dose distributions of stereotactic ablative radiotherapy (SABR) for lung cancer using volumetric-modulated arc therapy (VMAT) technique. A total of 30 patients who underwent SABR for lung cancer were selected retrospectively. Every patient was immobilized using Body Pro-Lok with a vacuum bag customized for each patient body shape. Structure sets were generated to include the patient body inside the body structure with and without the immobilization device. Dose distributions, with and without the immobilization device, were calculated using identical VMAT plans for each patient. Correlations between the change in dose-volumetric parameters and the MU fraction of photon beams penetrating through the immobilization device were analyzed with Pearson correlation coefficients (r). The maximum change in D95%, D100%, and the minimum, maximum and mean dose to the planning target volume (PTV) due to the immobilization device were 5%, 7%, 4%, 5%, and 5%, respectively. The maximum changes in the maximum dose to the spinal cord, esophagus, heart, and trachea were 1.3 Gy, 0.9 Gy, 1 Gy, and 1.7 Gy, respectively. Strong correlations were observed between the changes in PTV D95%, the minimum, the maximum, and the mean dose to the PTV, the maximum dose to the esophagus and heart, and the MU fractions, showing values of r higher than 0.7. The decrease in dose to the target volume was considerable for lung SABR using VMAT technique, especially when MU fraction was large.

Immobilization of α-Amylase from Anoxybacillus sp. SK3-4 on ReliZyme and Immobead Supports

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Ummirul Mukminin Kahar

2016-09-01

Full Text Available α-Amylase from Anoxybacillus sp. SK3-4 (ASKA is a thermostable enzyme that produces a high level of maltose from starches. A truncated ASKA (TASKA variant with improved expression and purification efficiency was characterized in an earlier study. In this work, TASKA was purified and immobilized through covalent attachment on three epoxide (ReliZyme EP403/M, Immobead IB-150P, and Immobead IB-150A and an amino-epoxide (ReliZyme HFA403/M activated supports. Several parameters affecting immobilization were analyzed, including the pH, temperature, and quantity (mg of enzyme added per gram of support. The influence of the carrier surface properties, pore sizes, and lengths of spacer arms (functional groups on biocatalyst performances were studied. Free and immobilized TASKAs were stable at pH 6.0–9.0 and active at pH 8.0. The enzyme showed optimal activity and considerable stability at 60 °C. Immobilized TASKA retained 50% of its initial activity after 5–12 cycles of reuse. Upon degradation of starches and amylose, only immobilized TASKA on ReliZyme HFA403/M has comparable hydrolytic ability with the free enzyme. To the best of our knowledge, this is the first report of an immobilization study of an α-amylase from Anoxybacillus spp. and the first report of α-amylase immobilization using ReliZyme and Immobeads as supports.

High-level waste immobilization program: an overview

International Nuclear Information System (INIS)

Bonner, W.R.

1979-09-01

The High-Level Waste Immobilization Program is providing technology to allow safe, affordable immobilization and disposal of nuclear waste. Waste forms and processes are being developed on a schedule consistent with national needs for immobilization of high-level wastes stored at Savannah River, Hanford, Idaho National Engineering Laboratory, and West Valley, New York. This technology is directly applicable to high-level wastes from potential reprocessing of spent nuclear fuel. The program is removing one more obstacle previously seen as a potential restriction on the use and further development of nuclear power, and is thus meeting a critical technological need within the national objective of energy independence

Immobilization routes - they're not standing still

Energy Technology Data Exchange (ETDEWEB)

Basta, N

1982-04-19

A review of the current stage of research into enzyme immobilization and the application of this technology in food processing and biomass-energy conversion is presented. The major success of the technology at present is the production of high-fructose corn syrup in the U.S. A commercial-scale plant to make sweeteners from cheese whey using immobilized lactase has come onstream in the U.K. Of two other processes reported, one uses immobilized bacteria to treat waste-water and produces pipeline-quality methane, the other holds promise for cutting the cost of corn-to-ethanol processing and enhancing the performance of cellulose-to-ethanol routes.

Preparation and characterization of two types of covalently immobilized amyloglucosidase

Directory of Open Access Journals (Sweden)

ZORAN VUJCIC

2005-05-01

Full Text Available Amyloglucosidase from A. niger was covalently immobilized onto poly (GMA-co-EGDMA by the glutaraldehyde and periodate method. The immobilization of amyloglucosidase after periodate oxidation gave a preparate with the highest specific activity reported so far on similar polymers. The obtained immobilized preparates show the same pH optimum, but a higher temperature optimum compared with the soluble enzyme. The kinetic parameters for the hydrolysis of soluble starch by free and both immobilized enzymes were determined.

Immobilization of Aspergillus niger cellulase on multiwall carbon nanotubes for cellulose hydrolysis.

Science.gov (United States)

Ahmad, Razi; Khare, Sunil Kumar

2018-03-01

In present study, Aspergillus niger cellulase was immobilized onto functionalized multiwalled carbon nanotubes (MWCNTs) via carbodiimide coupling. MWCNTs offer unique advantages including enhanced electronics properties, a large edge to basal plane ratio, rapid electrode kinetics and it's possess higher tensile strength properties due to their structural arrangements. The immobilization was confirmed by FTIR (Fourier transform infrared spectroscopy) and SEM (scanning electron microscope). The bionanoconjugates prepared under optimized condition retained 85% activity with improved pH and thermal stability. The t 1/2 of immobilized cellulase at 70 °C was four fold higher than free enzyme. The Km value indicates that affinity of bionanoconjugates towards substrate has increased by two times. The preparation could be reused ten times without much loss in enzyme activity. The enhanced catalytic efficiency, stability and reusability makes it useful for efficient cellulose hydrolysis. Copyright © 2017 Elsevier Ltd. All rights reserved.

Drop drying on surfaces determines chemical reactivity - the specific case of immobilization of oligonucleotides on microarrays

Science.gov (United States)

2013-01-01

Background Drop drying is a key factor in a wide range of technical applications, including spotted microarrays. The applied nL liquid volume provides specific reaction conditions for the immobilization of probe molecules to a chemically modified surface. Results We investigated the influence of nL and μL liquid drop volumes on the process of probe immobilization and compare the results obtained to the situation in liquid solution. In our data, we observe a strong relationship between drop drying effects on immobilization and surface chemistry. In this work, we present results on the immobilization of dye labeled 20mer oligonucleotides with and without an activating 5′-aminoheptyl linker onto a 2D epoxysilane and a 3D NHS activated hydrogel surface. Conclusions Our experiments identified two basic processes determining immobilization. First, the rate of drop drying that depends on the drop volume and the ambient relative humidity. Oligonucleotides in a dried spot react unspecifically with the surface and long reaction times are needed. 3D hydrogel surfaces allow for immobilization in a liquid environment under diffusive conditions. Here, oligonucleotide immobilization is much faster and a specific reaction with the reactive linker group is observed. Second, the effect of increasing probe concentration as a result of drop drying. On a 3D hydrogel, the increasing concentration of probe molecules in nL spotting volumes accelerates immobilization dramatically. In case of μL volumes, immobilization depends on whether the drop is allowed to dry completely. At non-drying conditions, very limited immobilization is observed due to the low oligonucleotide concentration used in microarray spotting solutions. The results of our study provide a general guideline for microarray assay development. They allow for the initial definition and further optimization of reaction conditions for the immobilization of oligonucleotides and other probe molecule classes to different

Electron beam technology for production of preparations of immobilized enzymes

International Nuclear Information System (INIS)

Gonchar, A.M.; Auslender, V.L.; Polyakov, V.A.

1995-01-01

Possibility of electron beam usage for proteases immobilization on 1,4-polyalkylene oxide (1,4-PAO) was studied to obtain biologically active complex for multi-purpose usage. It is shown that immobilization of Bacillus Subtilis protease is done due to free-radical linking of enzyme and carrier with formation of mycelium-like structures. Immobilization improves heat resistance of enzyme up to 60 centigrade without substrate and up to 80 centigrade in presence of substrate, widens range pH activity in comparison with non-immobilized forms. Immobilized proteases does not contain peroxides and long-live radicals. Our results permitted to create technologies for production of medical and veterinary preparations, active components for wool washing agents and leather fabrication technology

Studies on the preparation of immobilized enzymes by radiopolymerization, (9)

International Nuclear Information System (INIS)

Kawashima, Koji; Fujino, Satomi; Hayashi, Toru; Kim, Sung-K.

1982-01-01

Glucose Oxidase (GOD, EC 1, 1, 3, 4) was immobilized in the form of the beads by the radiation polymerization method under low temperature and the enzymatic characteristics were investigated. 1) Polyethyleneglycol dimethacrylate and acrylamide were favorable compounds for the immobilization of GOD. 2) Neither optimum pH nor pH stability was changed after immobilization treatment. 3) Optimum reaction temperature was shifted by 5 0 C to the higher side and heat stability was improved. 4) Immobilized GOD showed activity up to 60U per gram of dried polymer. 5) The small beads had retained high activities (10 - 80%) 6) The immobilized GOD was not leached out from the polymer matrix. (author)

Haloalkane hydrolysis with an immobilized haloalkane dehalogenase.

Science.gov (United States)

Dravis, B C; Swanson, P E; Russell, A J

2001-11-20

Haloalkane dehalogenase from Rhodococcus rhodochrous was covalently immobilized onto a polyethyleneimine impregnated gamma-alumina support. The dehalogenating enzyme was found to retain greater than 40% of its original activity after immobilization, displaying an optimal loading (max. activity/supported protein) of 70 to 75 mg/g with an apparent maximum (max. protein/support) of 156 mg/g. The substrate, 1,2,3-trichloropropane, was found to favorably partition (adsorb) onto the inorganic alumina carrier (10 to 20 mg/g), thereby increasing the local reactant concentration with respect to the catalyst's environment, whereas the product, 2,3-dichloropropan-1-ol, demonstrated no affinity. Additionally, the inorganic alumina support exhibited no adverse effects because of solvent/component incompatibilities or deterioration due to pH variance (pH 7.0 to 10.5). As a result of the large surface area to volume ratio of the support matrix and the accessibility of the bound protein, the immobilized biocatalyst was not subject to internal mass transfer limitations. External diffusional restrictions could be eliminated with simple agitation (mixing speed: 50 rpm; flux: 4.22 cm/min). The pH-dependence of the immobilized dehalogenase was essentially the same as that for the native enzyme. Finally, both the thermostability and resistance toward inactivation by organic solvent were improved by more than an order of magnitude after immobilization. Copyright 2001 John Wiley & Sons, Inc.

Biohydrogen production from rotten orange with immobilized mixed culture: Effect of immobilization media for various composition of substrates

Energy Technology Data Exchange (ETDEWEB)

Damayanti, Astrilia, E-mail: liasholehasd@gmail.com [Department of Chemical Engineering, Faculty of Engineering, Semarang State University, E1 Building, 2nd floor, Kampus Sekaran, Gunungpati, Semarang 50229 (Indonesia); Department of Chemical Engineering, Faculty of Engineering, Gadjah Mada University, Jl. Grafika No. 2, Kampus UGM, Yogyakarta 55281 (Indonesia); Sarto,; Syamsiah, Siti; Sediawan, Wahyudi B. [Department of Chemical Engineering, Faculty of Engineering, Gadjah Mada University, Jl. Grafika No. 2, Kampus UGM, Yogyakarta 55281 (Indonesia)

2015-12-29

Enriched–immobilized mixed culture was utilized to produce biohydrogen in mesophilic condition under anaerobic condition using rotten orange as substrate. The process was conducted in batch reactors for 100 hours. Microbial cultures from three different sources were subject to a series of enrichment and immobilized in two different types of media, i.e. calcium alginate (CA, 2%) and mixture of alginate and activated carbon (CAC, 1:1). The performance of immobilized culture in each media was tested for biohydrogen production using four different substrate compositions, namely orange meat (OM), orange meat added with peel (OMP), orange meat added with limonene (OML), and mixture of orange meat and peel added with limonene (OMPL). The results show that, with immobilized culture in CA, the variation of substrate composition gave significant effect on the production of biohydrogen. The highest production of biohydrogen was detected for substrate containing only orange meet, i.e. 2.5%, which was about 3-5 times higher than biohydrogen production from other compositions of substrate. The use of immobilized culture in CAC in general has increased the hydrogen production by 2-7 times depending on the composition of substrate, i.e. 5.4%, 4.8%, 5.1%, and 4.4% for OM, OMP, OML, and OMPL, respectively. The addition of activated carbon has eliminated the effect of inhibitory compounds in the substrate. The major soluble metabolites were acetic acid, propionic acid, and butyric acid.

Biohydrogen production from rotten orange with immobilized mixed culture: Effect of immobilization media for various composition of substrates

Science.gov (United States)

Damayanti, Astrilia; Sarto, Syamsiah, Siti; Sediawan, Wahyudi B.

2015-12-01

Enriched-immobilized mixed culture was utilized to produce biohydrogen in mesophilic condition under anaerobic condition using rotten orange as substrate. The process was conducted in batch reactors for 100 hours. Microbial cultures from three different sources were subject to a series of enrichment and immobilized in two different types of media, i.e. calcium alginate (CA, 2%) and mixture of alginate and activated carbon (CAC, 1:1). The performance of immobilized culture in each media was tested for biohydrogen production using four different substrate compositions, namely orange meat (OM), orange meat added with peel (OMP), orange meat added with limonene (OML), and mixture of orange meat and peel added with limonene (OMPL). The results show that, with immobilized culture in CA, the variation of substrate composition gave significant effect on the production of biohydrogen. The highest production of biohydrogen was detected for substrate containing only orange meet, i.e. 2.5%, which was about 3-5 times higher than biohydrogen production from other compositions of substrate. The use of immobilized culture in CAC in general has increased the hydrogen production by 2-7 times depending on the composition of substrate, i.e. 5.4%, 4.8%, 5.1%, and 4.4% for OM, OMP, OML, and OMPL, respectively. The addition of activated carbon has eliminated the effect of inhibitory compounds in the substrate. The major soluble metabolites were acetic acid, propionic acid, and butyric acid.

Biohydrogen production from rotten orange with immobilized mixed culture: Effect of immobilization media for various composition of substrates

International Nuclear Information System (INIS)

Damayanti, Astrilia; Sarto,; Syamsiah, Siti; Sediawan, Wahyudi B.

2015-01-01

Enriched–immobilized mixed culture was utilized to produce biohydrogen in mesophilic condition under anaerobic condition using rotten orange as substrate. The process was conducted in batch reactors for 100 hours. Microbial cultures from three different sources were subject to a series of enrichment and immobilized in two different types of media, i.e. calcium alginate (CA, 2%) and mixture of alginate and activated carbon (CAC, 1:1). The performance of immobilized culture in each media was tested for biohydrogen production using four different substrate compositions, namely orange meat (OM), orange meat added with peel (OMP), orange meat added with limonene (OML), and mixture of orange meat and peel added with limonene (OMPL). The results show that, with immobilized culture in CA, the variation of substrate composition gave significant effect on the production of biohydrogen. The highest production of biohydrogen was detected for substrate containing only orange meet, i.e. 2.5%, which was about 3-5 times higher than biohydrogen production from other compositions of substrate. The use of immobilized culture in CAC in general has increased the hydrogen production by 2-7 times depending on the composition of substrate, i.e. 5.4%, 4.8%, 5.1%, and 4.4% for OM, OMP, OML, and OMPL, respectively. The addition of activated carbon has eliminated the effect of inhibitory compounds in the substrate. The major soluble metabolites were acetic acid, propionic acid, and butyric acid

Uranium Immobilization in Wetland Soils

Science.gov (United States)

Jaffe, Peter R.; Koster van Groos, Paul G.; Li, Dien; Chang, Hyun-Shik; Seaman, John C.; Kaplan, Daniel I.; Peacock, Aaron D.; Scheckel, Kirk

2014-05-01

stronger for the mesocosms with the higher Fe(II) load. Analysis via XANES showed that a fraction (up to ~1/3) of uranium was reduced to U(IV), for mesocosms operated under low iron loading, indicating that iron cycling in the rhizosphere also results in uranium reduction and immobilization. For mesocosms operating under the higher iron loading, the fraction of uranium immobilized as U(IV) was much lower, indicating that uranium co-precipitation with iron might have been the dominant immobilization process. In parallel to these mesocosm experiments, dialysis samplers have been deployed at the Savannah River National Laboratory near a creek with uranium contamination, to determine dissolved species, including Fe(II) and U(VI) in these wetland soils and their seasonal variability. The results show that there is a strong seasonal variability in dissolved iron and uranium, indicating a strong immobilization during the growing season, which is consistent with the mesocosm experimental results that the rhizosphere iron and uranium cycling are closely linked.

Chitosan-immobilized pectinolytics with novel catalytic features and fruit juice clarification potentialities.

Science.gov (United States)

Irshad, Muhammad; Murtza, Aimen; Zafar, Muddassar; Bhatti, Khizar Hayat; Rehman, Abdul; Anwar, Zahid

2017-11-01

Biological macromolecules are primarily composed of complex polysaccharides that strengthen microbial growth for the production of industrially relevant enzymes. The presence of polysaccharides in the form of the disrupted cell wall and cell materials are among major challenges in the fruit juice industry. The breakdown of such biological macromolecules including cellulose and pectin is vital for the juices processing. In this background, pectinolytic enzymes including polygalacturonase (PG), pectin lyase (PL), and pectin methylesterase (PME) were isolated from Aspergillus ornatus, statistically optimized and purified via ammonium sulfate fractionation (ASF), dialysis, and Sephadex G-100 gel permeation chromatography. After passing through Sephadex G-100 column, PG, PL, and PME were 2.60-fold, 3.30-fold, and 4.52-fold purified with specific activities of 475.2U/mg, 557.1U/mg, and 205.7U/mg. The active PG, PL, and PME, each separately, were surface immobilized using various concentrations of chitosan and dextran polyaldehyde as a macromolecular crosslinking agent. Prior to exploit for juice clarification purposes, various parameters including pH, thermal and Michaelis-Menten kinetic constants of purified and chitosan-immobilized fractions were investigated. A considerable improvement in the pH and thermal profiles was recorded after immobilization. However, the negligible difference between the K m and V max values of purified free and chitosan-immobilized fractions revealed that the conformational flexibility of pectinolytics was retained as such. A significant color and turbidity reductions were recorded after 60min treatment with CTS-PG, followed by CTS-PME, and CTS-PL. It can be concluded that the clarification of apples, mango, peach, and apricot juices was greatly affected by CTS-PG, CTS-PME, and CTS-PL treatments rendering them as potential candidatures for food industry applications. Copyright © 2017 Elsevier B.V. All rights reserved.

Biosorption of uranium from wastewater by ZVI-SRB immobilized in calcium alginate

International Nuclear Information System (INIS)

Wang Aihe; Zhang Wei; Hu Kaiguang

2009-01-01

A ZVI-SRB was immobilized in calcium alginate gel beads,and the immobilized ZVI-SRB was used for removing uranium from wasterwater. The kinetics of uranium biosorption by the immobilized ZVI-SRB and the immobilized SRB was investigated. The results show that the immobilized ZVI-SRB and SRB were effective in removing uranium from wasterwater, and their maximal absorption capacities were up to 312.50 and 256.41 mg/g respectively. The kinetics of uranium biosorption onto the immobilized ZVI-SRB and SRB followed pseudo-second order model. (authors)

Efficiency of fly ash belite cement and zeolite matrices for immobilizing cesium

International Nuclear Information System (INIS)

Goni, S.; Guerrero, A.; Lorenzo, M.P.

2006-01-01

The efficiency of innovative matrices for immobilizing cesium is presented in this work. The matrix formulation included the use of fly ash belite cement (FABC-2-W) and gismondine-type Na-P1 zeolite, both of which are synthesized from fly ash of coal combustion. The efficiency for immobilizing cesium is evaluated from the leaching test ANSI/ANS 16.1-1986 at the temperature of 40 deg. C, from which the apparent diffusion coefficient of cesium is obtained. Matrices with 100% of FABC-2-W are used as a reference. The integrity of matrices is evaluated by porosity and pore-size distribution from mercury intrusion porosimetry, X-ray diffraction and nitrogen adsorption analyses. Both matrices can be classified as good solidify systems for cesium, specially the FABC-2-W/zeolite matrix in which the replacement of 50% of belite cement by the gismondine-type Na-P1 zeolite caused a decrease of two orders of magnitude of cesium mean Effective Diffusion Coefficient (D e ) (2.8e-09 cm 2 /s versus 2.2e-07 cm 2 /s, for FABC-2-W/zeolite and FABC-2-W matrices, respectively)

Soluble and immobilized graphene oxide activates complement system differently dependent on surface oxidation state

DEFF Research Database (Denmark)

Wibroe, Peter Popp; Petersen, Søren Vermehren; Bovet, Nicolas Emile

2016-01-01

on two related elements of innate immunity: the complement system and interleukin-6 (IL-6) release in human blood. In solution, there was a decrease in GO-mediated complement activation with decreasing surface oxygen content (and altered oxygen functionality), whereas with immobilized GO complement...... response were reversed and increased with decreasing oxygen content. GO solutions, at concentrations below complement activating threshold, did not induce IL-6 release from human blood leukocytes, and further dampened lipopolysaccharide-induced IL-6 release in the whole blood. The latter effect became more...... profound with GO's having higher oxygen content. This protective role of GO solutions, however, disappeared at higher concentrations above complement-activating threshold. We discuss these results in relation to GO surface structure and properties, and implications for local administration and development...

Immobilized acclimated biomass-powdered activated carbon for the bioregeneration of granular activated carbon loaded with phenol and o-cresol.

Science.gov (United States)

Toh, Run-Hong; Lim, Poh-Eng; Seng, Chye-Eng; Adnan, Rohana

2013-09-01

The objectives of the study are to use immobilized acclimated biomass and immobilized biomass-powdered activated carbon (PAC) as a novel approach in the bioregeneration of granular activated carbon (GAC) loaded with phenol and o-cresol, respectively, and to compare the efficiency and rate of the bioregeneration of the phenolic compound-loaded GAC using immobilized and suspended biomasses under varying GAC dosages. Bioregeneration of GAC loaded with phenol and o-cresol, respectively, was conducted in batch system using the sequential adsorption and biodegradation approach. The results showed that the bioregeneration efficiency of GAC loaded with phenol or o-cresol was basically the same irrespective of whether the immobilized or suspended biomass was used. Nonetheless, the duration for bioregeneration was longer under immobilized biomass. The beneficial effect of immobilized PAC-biomass for bioregeneration is the enhancement of the removal rate of the phenolic compounds via adsorption and the shortening of the bioregeneration duration. Copyright © 2013 Elsevier Ltd. All rights reserved.

Immobilization of Thermomyces lanuginosus lipase on multi-walled carbon nanotubes and its application in the hydrolysis of fish oil

Science.gov (United States)

Matuoog, Naeema; Li, Kai; Yan, Yunjun

2017-12-01

In this study, lipase from Thermomyces lanuginosus (TLL) was immobilized on carbon nanotubes (MWCNTs) by physical adsorption, and the immobilizing conditions were optimized for maximum activity. The effects of enzyme loading, pH, temperature and time on the immobilization efficiency and specific activity were evaluated. The highest enzyme activity and immobilization efficiency of 90.66% and 110.5%, respectively, were achieved when the immobilized pH was 8, and a high rate of recovery activity of 111.3% occurred at 45 °C with 30-60 min providing a good result. When the immobilization efficiency was 95.8%, the recovery activity was 112.4%. The immobilization time had little effect on the immobilization efficiency, and 6 mg g-1 of lipase provided the highest immobilization efficiency of 97.78% and recovery activity of 112.8%. When the immobilized lipase was utilized to enrich docosahexaenoic acid (DHA) from fish oil, the DHA content increased with increasing amount of lipase up to 9 mg g-1. The water content had a clear effect when of 50% water was used at 45 °C and at a pH of 7 after 10 h. The DHA contents were 4.2-fold and 2.5-fold greater than the initial content of DHA fish oil for TLL-MWCNTs and free lipase, respectively. The degrees of hydrolysis after 6 cycles of successive use were over 80% and 62% for the immobilized TLL and free TLL, respectively, indicating the system recyclability and the ease of use of the immobilized TLL in industrial applications, especially in the fields of food and medicine.

Analysis of direct immobilized recombinant protein G on a gold surface

International Nuclear Information System (INIS)

Kim, Hyunhee; Kang, Da-Yeon; Goh, Hyun-Jeong; Oh, Byung-Keun; Singh, Ravindra P.; Oh, Soo-Min; Choi, Jeong-Woo

2008-01-01

Abstact: For the immobilization of IgG, various techniques such as chemical linker, thiolated protein G methods, and fragmentation of antibodies have been reported [Y.M. Bae, B.K. Oh, W. Lee, W.H. Lee, J.W. Choi, Biosensors Bioelectron. 21 (2005) 103; W. Lee, B.K. Oh, W.H. Lee, J.W. Choi, Colloids Surf. B-Biointerfaces, 40 (2005) 143; A.A. Karyakin, G.V. Presnova, M.Y. Rubtsova, A.M. Egorov, Anal. Chem. 72 (2000) 3805]. Here, we modified the immunoglobulin Fc-binding B-domain of protein G to contain two cysteine residues at its C-terminus by a genetic engineering technique. The resulting recombinant protein, RPGcys, retained IgG-binding activity in the same manner as native protein G. RPGcys was immobilized on a gold surface by strong affinity between thiol of cysteine and gold. The orientations of both IgG layers immobilized on the base recombinant protein Gs were analyzed by fluorescence microscope, atomic force microscope (AFM), and surface plasmon resonance (SPR). Our data revealed that IgG-binding activity of RPGcys on gold surface significantly increased in comparison to wild type of protein G (RPGwild), which was physically adsorbed due to absence of cysteine residue. Immobilization of highly oriented antibodies based on cysteine-modified protein G could be useful for the fabrication of immunosensor systems

Immobilization of indigenous holocellulase on iron oxide (Fe2O3) nanoparticles enhanced hydrolysis of alkali pretreated paddy straw.

Science.gov (United States)

Kumar, Ajay; Singh, Surender; Tiwari, Rameshwar; Goel, Renu; Nain, Lata

2017-03-01

The holocellulase from Aspergillus niger SH3 was characterized and found to contain 125 proteins including cellulases (26), hemicellulases (21), chitinases (10), esterases (6), amylases (4) and hypothetical protein (32). The crude enzyme was immobilized on five different nanoparticles (NPs) via physical adsorption and covalent coupling methods. The enzyme-nanoparticle complexes (ENC) were screened for protein binding, enzymatic activities and immobilization efficiency. Magnetic enzyme-nanoparticle complexes (MENC) showed higher immobilization efficiency (60-80%) for most of the enzymes. MENC also showed better catalytic efficiencies in term of higher V max and lower K m than free enzyme. Saccharification yields from alkali treated paddy straw were higher (375.39mg/gds) for covalently immobilized MENC than free enzyme (339.99mg/gds). The immobilized enzyme was used for two cycles of saccharification with 55% enzyme recovery. Hence, this study for the first time demonstrated the immobilization of indigenous enzyme and its utilization for saccharification of paddy straw. Copyright © 2016 Elsevier B.V. All rights reserved.

Immobilization of cellulase on functionalized cobalt ferrite nanoparticles

Energy Technology Data Exchange (ETDEWEB)

Bohara, Raghvendra Ashok; Thorat, Nanasaheb Devappa; Pawar, Shivaji Hariba [Center for Interdisciplinary Research, D. Y. Patil University, Kolhapur (India)

2016-01-15

Amine functionalized cobalt ferrite (AF-CoFe{sub 2}O{sub 4}) magnetic nanoparticles (MNPs) were used for immobilization of cellulase enzyme via 1-ethyl-3-[3-dimethylaminopropyl] carbodiimide hydrochloride (EDS) and N-hydroxysuccinimide (NHS) coupling reaction. The structural, morphological and magnetic properties of AF-CoFe{sub 2}O{sub 4} were determined. TEM micrograph revealed a mean diameter of -8 nm and showed that the AF-CoFe{sub 2}O{sub 4} remain distinct with no significant change in size after binding with cellulase. Fourier transform infrared (FT-IR) spectroscopy confirmed the binding of cellulase to AF-CoFe{sub 2}O{sub 4}. The properties of immobilized cellulase were investigated by optimizing binding efficiency, pH, temperature and reusability. The results showed that the immobilized cellulase has higher thermal stability than free cellulase, which might be due to covalent interaction between cellulase and AF-CoFe{sub 2}O{sub 4} surface. The immobilized cellulase also showed good reusability after recovery. Therefore, AF-CoFe{sub 2}O{sub 4} MNPs can be considered as promising candidate for enzyme immobilization.

Characterization of modified zeolite as microbial immobilization media on POME anaerobic digestion

Science.gov (United States)

Cahyono, Rochim B.; Ismiyati, Sri; Ginting, Simparmin Br; Mellyanawaty, Melly; Budhijanto, Wiratni

2018-03-01

As the world’s biggest palm oil producer, Indonesia generates also huge amount of Palm Oil Mill Effluent (POME) wastewater and causes serious problem in environment. In conventional method, POME was converted into biogas using lagoon system which required extensive land area. Anaerobic Fluidized Bed Reactor (AFBR) proposes more effective biogas producing with smaller land area. In the proposed system, a immobilization media would be main factor for enhancing productivity. This research studied on characterization of Lampung natural zeolite as immobilization media in the AFBR system for POME treatment. Various activation method such as physical and chemical were attempted to create more suitable material which has larger surface area, pore size distribution as well as excellent surface structures. The physical method was applied by heating up the material till 400°C while HCl was used on the chemical activation. Based on the result, the chemical activation increased the surface area significantly into 71 m2/g compared to physical as well as original zeolite. The strong acid material was quite effective to enforce the impurities within zeolite pore structure compared to heating up the material. According to distribution data, the Lampung zeolite owned the pore size with the range of 3 – 5 μm which was mesopore material. The pore size was appropriate for immobilization media as it was smaller than size of biogas microbial. The XRD patterns verified that chemical activation could maintain the zeolite structure as the original. Obviously, the SEM photograph showed apparent structure and pore size on the modified zeolite using chemical method. The testing of modified zeolite on the batch system was done to evaluate the characterization process. The modified zeolite using chemical process resulted fast reduction of COD and stabilized the volatile fatty acid as the intermediate product of anaerobic digestion, especially in the beginning of the process. Therefore, the

Maintenance Plan for the Hanford Immobilized Low-Activity Tank Waste Performance Assessment

International Nuclear Information System (INIS)

MANN, F.M.

2000-01-01

The plan for maintaining the Hanford Immobilized Low-Activity Tank Waste Performance Assessment (PA) is described. The plan includes expected work on PA reviews and revisions, waste reports, monitoring, other operational activities, etc

Waste incineration and immobilization for nuclear facilities, April--September 1977

International Nuclear Information System (INIS)

Johnson, A.J.; Fong, L.Q.

1978-01-01

Fluidized bed incineration and waste immobilization processes are being developed to process the types of waste expected from nuclear facilities. An air classification system has been developed to separate tramp metal from shredded combustible solid waste prior to the waste being fed to a fluidized-bed pilot-plant incinerator. Used organic ion exchange resin with up to 55 percent water has been effectively burned in the fluidized bed incinerator. Various methods of feeding waste into the incinerator were investigated as alternatives to the present compression screw; an extrusion ram was found to suffer extensive damage from hard particles in tested waste. A bench-scale continuous waste immobilization process has been operated and has produced glass from incinerator residue and other types of waste materials

Magnetically modified bacterial cellulose: A promising carrier for immobilization of affinity ligands, enzymes, and cells

Energy Technology Data Exchange (ETDEWEB)

Baldikova, Eva [Global Change Research Institute, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic); Pospiskova, Kristyna [Regional Centre of Advanced Technologies and Materials, Palacky University, Slechtitelu 27, 783 71 Olomouc (Czech Republic); Ladakis, Dimitrios; Kookos, Ioannis K. [Department of Chemical Engineering, University of Patras, 26504 Patras, Rio (Greece); Koutinas, Apostolis A. [Department of Food Science and Human Nutrition, Agricultural University of Athens, Iera Odos 75, Athens 11855 (Greece); Safarikova, Mirka [Global Change Research Institute, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic); Department of Nanobiotechnology, Biology Centre, ISB, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic); Safarik, Ivo, E-mail: safarik@nh.cas.cz [Global Change Research Institute, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic); Regional Centre of Advanced Technologies and Materials, Palacky University, Slechtitelu 27, 783 71 Olomouc (Czech Republic); Department of Nanobiotechnology, Biology Centre, ISB, CAS, Na Sadkach 7, 370 05 Ceske Budejovice (Czech Republic)

2017-02-01

Bacterial cellulose (BC) produced by Komagataeibacter sucrofermentans was magnetically modified using perchloric acid stabilized magnetic fluid. Magnetic bacterial cellulose (MBC) was used as a carrier for the immobilization of affinity ligands, enzymes and cells. MBC with immobilized reactive copper phthalocyanine dye was an efficient adsorbent for crystal violet removal; the maximum adsorption capacity was 388 mg/g. Kinetic and thermodynamic parameters were also determined. Model biocatalysts, namely bovine pancreas trypsin and Saccharomyces cerevisiae cells were immobilized on MBC using several strategies including adsorption with subsequent cross-linking with glutaraldehyde and covalent binding on previously activated MBC using sodium periodate or 1,4-butanediol diglycidyl ether. Immobilized yeast cells retained approximately 90% of their initial activity after 6 repeated cycles of sucrose solution hydrolysis. Trypsin covalently bound after MBC periodate activation was very stable during operational stability testing; it could be repeatedly used for ten cycles of low molecular weight substrate hydrolysis without loss of its initial activity. - Highlights: • Bacterial cellulose was magnetically modified with magnetic fluid. • Magnetic cellulose is an efficient carrier for affinity ligands. • Enzymes and cells can be efficiently immobilized to magnetic cellulose.

Immobilization of antibodies and enzyme-labeled antibodies by radiation polymerization

International Nuclear Information System (INIS)

Kumakura, M.; Kaetsu, I.; Suzuki, M.; Adachi, S.

1983-01-01

Immobilization of antibodies and enzyme-labeled antibodies by radiation polymerization at low temperatures was studied. The antibody activity of antibody was not affected by irradiation at an irradiation dose of below 8 MR and low temperatures. Immobilization of peroxidase-labeled anti-rabbit IgG goat IgG, anti-peroxidase, peroxidase, and anti-alpha-fetoprotein was carried out with hydrophilic and hydrophobic monomers. The activity of the immobilized enzyme-labeled antibody membranes varied with the thickness of the membranes and increased with decreasing membrane thickness. The activity of the immobilized antibody particles was varied by particle size. Immobilized anti-alpha-fetoprotein particles and membranes can be used for the assay of alpha-fetoprotein by the antigen-antibody reaction, such as a solid-phase sandwich method with high sensitivity

Covalent immobilization of lipase from Candida rugosa on Eupergit®

Directory of Open Access Journals (Sweden)

Bezbradica Dejan I.

2005-01-01

Full Text Available An approach is presented for the stable covalent immobilization of Upase from Candida rugosa on Eupergit® with a high retention of hydrolytic activity. It comprises covalent bonding via lipase carbohydrate moiety previously modified by periodate oxidation, allowing a reduction in the involvement of the enzyme functional groups that are probably important in the catalytic mechanism. The hydrolytic activities of the lipase immobilized on Eupergif1 by two conventional methods (via oxirane group and via glutaralde-hyde and with periodate method were compared. Results of lipase assays suggest that periodate method is superior for lipase immobilization on Eupergit® among methods applied in this study with respect to both, yield of immobilization and hydrolytic activity of the immobilized enzyme.

Cell immobilization by radiation polymerization-a comparative study

International Nuclear Information System (INIS)

Dahlan bin Hj Mohd; Abu Bakar bin Salleh; Che Nyonya binti Abd Razak; Meheran binti Hamenudin; Kamaruzaman bin Ampon; Wan Md Zin bin Wan Yunus; Mahiran binti Basri

1991-01-01

An extracellular lipase producing fungus, Rhizopus rhizopodi formis was immobilised using radiation-induced polyHEMA, alginate and k-carrageenan. Immobilizations were done on spores since they showed better resistance against gamma radiation. The simultaneous radiation immobilization technique was found to be unsuitable because of contamination. Post-radiation immobilization using polyHEMA yielded 2-3 times more enzyme than the free cells. The value, however was slightly lower than the ones given by the cells immobilised using alginate or k-carrageenan, but the radiation-induced polymer was stronger and less likely to disintegrate

X-Shaped ZIF-8 for Immobilization Rhizomucor miehei Lipase via Encapsulation and Its Application toward Biodiesel Production

Directory of Open Access Journals (Sweden)

Miaad Adnan

2018-02-01

Full Text Available This study presents a one-step encapsulation method for synthesizing X-shaped zeolitic imidazolate frameworks (ZIF-8 and immobilizing Rhizomucor miehei lipase (RML. We proved that the morphological structure of ZIF-8 had changed after immobilization with enhanced characterization using a field-emission scanning electron microscope, an energy-dispersive spectrometer, a transmission electron microscope, a Fourier transform infrared spectrometer, and powder X-ray diffraction. The surface area and pore size of the carrier were investigated before and after immobilization using Brunauer–Emmett–Teller and Barrett–Joyner–Halenda methods, respectively. RML@ZIF-8 exhibited high recovery activity of up to 2632%, representing a 26-fold increase in its free lipase. Encapsulated RML was used for biodiesel production from soybean oil in an isooctane system with a conversion yield of 95.6% under optimum conditions. The resulting reusability of the immobilized enzyme indicated no substantial decline in the conversion yield, which remained at 84.7% of the initial activity after 10 cycles. The stability and high performance of the immobilized enzyme are attributed to the harmony between RML and ZIF-8 based on the easy synthesis of ZIF-8 and the short time required to immobilize RML.

TWRS retrieval and storage mission. Immobilized low-activity waste disposal plan

International Nuclear Information System (INIS)

Shade, J.W.

1998-01-01

The TWRS mission is to store, treat, and immobilize highly radioactive Hanford waste (current and future tank waste and the encapsulated cesium and strontium) in a safe, environmentally sound, and cost-effective manner (TWRS JMN Justification for mission need). The mission includes retrieval, pretreatment, immobilization, interim storage and disposal, and tank closure. As part of this mission, DOE has established the TWRS Office to manage all Hanford Site tank waste activities. The TWRS program has identified the need to store, treat, immobilize, and dispose of the highly radioactive Hanford Site tank waste and encapsulated cesium and strontium materials in an environmentally sound, safe, and cost-effective manner. To support environmental remediation and restoration at the Hanford Site a two-phase approach to using private contractors to treat and immobilize the low-activity and high-level waste currently stored in underground tanks is planned. The request for proposals (RFP) for the first phase of waste treatment and immobilization was issued in February 1996 (Wagoner 1996) and initial contracts for two private contractor teams led by British Nuclear Fuels Ltd. and Lockheed-Martin Advanced Environmental Services were signed in September 1996. Phase 1 is a proof-of-concept and commercial demonstration effort to demonstrate the technical and business feasibility of using private facilities to treat Hanford Site waste, maintain radiological, nuclear, process, and occupational safety; and maintain environmental protection and compliance while reducing lifecycle costs and waste treatment times. Phase 1 production of ILAW is planned to begin in June 2002 and could treat up to about 13 percent of the waste. Phase 1 production is expected to be completed in 2007 for minimum order quantities or 2011 for maximum order quantities. Phase 2 is a full-scale production effort that will begin after Phase 1 and treat and immobilize most of the waste. Phase 2 production is

Immobilization of inorganic pyrophosphatase on nanodiamond particles retaining its high enzymatic activity.

Science.gov (United States)

Rodina, Elena V; Valueva, Anastasiya V; Yakovlev, Ruslan Yu; Vorobyeva, Nataliya N; Kulakova, Inna I; Lisichkin, Georgy V; Leonidov, Nikolay B

2015-12-21

Nanodiamond (ND) particles are popular platforms for the immobilization of molecular species. In the present research, enzyme Escherichia coli inorganic pyrophosphatase (PPase) was immobilized on detonation ND through covalent or noncovalent bonding and its enzymatic activity was characterized. Factors affecting adsorption of PPase such as ND size and surface chemistry were studied. The obtained material is a submicron size association of ND particles and protein molecules in approximately equal amounts. Both covalently and noncovalently immobilized PPase retains a significant enzymatic activity (up to 95% of its soluble form) as well as thermostability. The obtained hybrid material has a very high enzyme loading capacity (∼1 mg mg(-1)) and may be considered as a promising delivery system of biologically active proteinaceous substances, particularly in the treatment of diseases such as calcium pyrophosphate crystal deposition disease and related pathologies. They can also be used as recoverable heterogeneous catalysts in the traditional uses of PPase.

Production and immobilization of alpha amylase using biotechnology techniques for use in biological and medical applications

International Nuclear Information System (INIS)

Mobasher, E.E.F.

2009-01-01

The immobilized enzymes on polymeric supports are prepared for purpose of repeated use and the possibilities of continuous reaction system. One of the most important properties is the stability of proteins when they are used in some medical and industrial applications. The immobilization of the enzymes improves this property as well as many other properties.In this study, alpha amylase was purified and immobilized onto two different polymers. α- amylase was used in this study for its biological and industrial applications. It is used in paper textile, pharmaceutical applications, food, and detergent industries. α- amylase was found in plants, animals, and microorganisms. Purification of α-amylase from microorganisms is the main source of α-amylase because it was excreted from many bacteria and fungi. In this study, α-amylase was purified from Aspergillus niger. Fractional precipitation of the α- amylase produced by A. niger with 80% ammonium sulphate saturation. The crude enzyme was applied on column chromatography packed with Sephadex G 100 for purification. The active eluents containing partially purified enzyme were collected for further investigation. The specific activity of α-amylase was (34.9 U/mg) which was corresponding to 2.09 fold purification for the tested organism. The purified α-amylase was immobilized by entrapment method into two types of polymers. One of them was natural consist of chitosan and alginate. The other polymer was synthetic consist of N- isopropyl acrylamide and alginate. The temperature optimum and thermal inactivation showed a severe loss in the activity of the free enzymes, while the temperature profile of the immobilized enzymes was much broader at higher temperatures demonstrating the effectiveness of the polymer protecting the enzymes. Also, the immobilized enzymes (natural polymer and synthetic polymer) showed higher thermal stability. Optimum ph and stability showed that immobilization of enzymes resulted in more

CT image-guided intensity-modulated therapy for paraspinal tumors using stereotactic immobilization

International Nuclear Information System (INIS)

Yenice, Kamil M.; Lovelock, D. Michael; Hunt, Margie A.; Lutz, Wendell R.; Fournier-Bidoz, Nathalie; Hua, C.-H.; Yamada, Josh; Bilsky, Mark; Lee, Henry; Pfaff, Karl; Spirou, Spiridon V.; Amols, Howard I.

2003-01-01

Purpose: To design and implement a noninvasive stereotactic immobilization technique with daily CT image-guided positioning to treat patients with paraspinal lesions accurately and to quantify the systematic and random patient setup errors occurring with this method. Methods and Materials: A stereotactic body frame (SBF) was developed for 'rigid' immobilization of paraspinal patients. The inherent accuracy of this system for stereotactic CT-guided treatment was evaluated with phantom studies. Seven patients with thoracic and lumbar spine lesions were immobilized with the SBF and positioned for 33 treatment fractions using daily CT scans. For all 7 patients, the daily setup errors, as assessed from the daily CT scans, were corrected at each treatment fraction. A retrospective analysis was also performed to assess what the impact on patient treatment would have been without the CT-based corrections (i.e., if patient setup had been performed only with the SBF). Results: The average magnitude of systematic and random errors from uncorrected patient setups using the SBF was approximately 2 mm and 1.5 mm (1 SD), respectively. For fixed phantom targets, the system accuracy for the SBF localization and treatment was shown to be within 1 mm (1 SD) in any direction. Dose-volume histograms incorporating these uncertainties for an intensity-modulated radiotherapy plan for lumbar spine lesions were generated, and the effects on the dose-volume histograms were studied. Conclusion: We demonstrated a very accurate and precise method of patient immobilization and treatment delivery based on a noninvasive SBF and daily image guidance for paraspinal lesions. The SBF provides excellent immobilization for paraspinal targets, with setup accuracy better than 2 mm (1 SD). However, for highly conformal paraspinal treatments, uncorrected systematic and random errors of 2 mm in magnitude can result in a significantly greater (>100%) dose to the spinal cord than planned, even though the

Chemical Immobilization Effect on Lithium Polysulfides for Lithium-Sulfur Batteries.

Science.gov (United States)

Li, Caixia; Xi, Zhucong; Guo, Dexiang; Chen, Xiangju; Yin, Longwei

2018-01-01

Despite great progress in lithium-sulfur batteries (LSBs), great obstacles still exist to achieve high loading content of sulfur and avoid the loss of active materials due to the dissolution of the intermediate polysulfide products in the electrolyte. Relationships between the intrinsic properties of nanostructured hosts and electrochemical performance of LSBs, especially, the chemical interaction effects on immobilizing polysulfides for LSB cathodes, are discussed in this Review. Moreover, the principle of rational microstructure design for LSB cathode materials with strong chemical interaction adsorbent effects on polysulfides, such as metallic compounds, metal particles, organic polymers, and heteroatom-doped carbon, is mainly described. According to the chemical immobilizing mechanism of polysulfide on LSB cathodes, three kinds of chemical immobilizing effects, including the strong chemical affinity between polar host and polar polysulfides, the chemical bonding effect between sulfur and the special function groups/atoms, and the catalytic effect on electrochemical reaction kinetics, are thoroughly reviewed. To improve the electrochemical performance and long cycling life-cycle stability of LSBs, possible solutions and strategies with respect to the rational design of the microstructure of LSB cathodes are comprehensively analyzed. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

Immobilization of Superoxide Dismutase on Polyelectrolyte-Functionalized Titania Nanosheets.

Science.gov (United States)

Rouster, Paul; Pavlovic, Marko; Szilagyi, Istvan

2018-02-16

The superoxide dismutase (SOD) enzyme was successfully immobilized on titania nanosheets (TNS) functionalized with the poly(diallyldimethylammonium chloride) (PDADMAC) polyelectrolyte. The TNS-PDADMAC solid support was prepared by hydrothermal synthesis followed by self-assembled polyelectrolyte layer formation. It was found that SOD strongly adsorbed onto oppositely charged TNS-PDADMAC through electrostatic and hydrophobic interactions. The TNS-PDADMAC-SOD material was characterized by light scattering and microscopy techniques. Colloidal stability studies revealed that the obtained nanocomposites possessed good resistance against salt-induced aggregation in aqueous suspensions. The enzyme kept its functional integrity upon immobilization; therefore, TNS-PDADMAC-SOD showed excellent superoxide radical anion scavenging activity. The developed system is a promising candidate for applications in which suspensions of antioxidant activity are required in the manufacturing processes. © 2018 Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

Degradation of methyl tert-butyl ether by gel immobilized Methylibium petroleiphilum PM1.

Science.gov (United States)

Chen, Dongzhi; Chen, Jianmeng; Zhong, Weihong; Cheng, Zhuowei

2008-07-01

Cells of Methylibium petroleiphilum PM1 were immobilized in gel beads to degrade methyl tert-butyl ether (MTBE). Calcium alginate, agar, polyacrylamide and polyvinvyl alcohol were screened as suitable immobilization matrices, with calcium alginate demonstrating the fastest MTBE-degradation rate. The rate was accelerated by 1.8-fold when the beads had been treated in physiological saline for 24h at 28 degrees C. MTBE degradation in mineral salts medium (MSM) was accompanied by the increase of biomass. The half-life of MTBE-degradation activity for the encapsulated cells stored at 28 degrees C was about 120 h, which was obviously longer than that of free cells (approximately 36 h). Efficient reusability of the beads up to 30 batches was achieved in poor nutrition solution as compared to only 6 batches in MSM. The immobilized cells could be operated in a packed-bed reactor for degradation of 10 mg L(-1) MTBE in groundwater with more than 99% removal efficiency at hydraulic retention time of 20 min. These results suggested that immobilized cells of PM1 in bioreactor might be applicable to a groundwater treatment system for the removal of MTBE.

Effect of photo-immobilization of epidermal growth factor on the cellular behaviors

International Nuclear Information System (INIS)

Ogiwara, Kazutaka; Nagaoka, Masato; Cho, Chong-Su; Akaike, Toshihiro

2006-01-01

We constructed photo-reactive epidermal growth factor (EGF) bearing p-azido phenylalanine at the C-terminal (HEGFP) by genetic engineering to investigate the possibility of immobilized EGF as a novel artificial extracellular matrix (ECM). The constructed recombinant protein was immobilized to glass surface by ultraviolet irradiation. A431 cells adhered both to HEGFP-immobilized and collagen-coated surfaces. Interaction between immobilized HEGFP and EGF receptors in the A431 cells was independent of Mg 2+ although integrin-mediated cell adhesion to natural ECMs is dependent on Mg 2+ . Phosphorylation of EGF receptors in A431 cells was induced by immobilized HEGFP as same as soluble EGF. DNA uptake of hepatocytes decreased by immobilized HEGFP whereas it increased by soluble EGF. Liver-specific functions of hepatocytes were maintained for 3 days by immobilized HEGFP whereas they were not maintained by soluble EGF, indicating that immobilized HEGFP follows different signal transduction pathway from soluble EGF

Production of cellulase and xylanase in a bubble gum column using immobilized Aspergillus niger KKS

Energy Technology Data Exchange (ETDEWEB)

Kang, Seong-Woo; Kim, Seung-Woo [Univ. of Suwon (Korea, Republic of); Lee, Jin-Suk [Korea Institute of Energy Research, Daejeon (Korea, Republic of)

1995-05-01

Aspergillus niger KKS, isolated from a farmland near Suwon, was immobilized on Celite and polyurethane foams. Enzyme activities produced by the immobilized cell system in a bubble column were higher than that of shake-flask culture. The enzyme productivities were twice as high. {Beta}-Glucosidase, {Beta}-xylosidase, and xylanase activities obtained in a bubble column were significant when the ground rice straw was used as a substrate. 9 refs., 2 figs., 3 tabs.

Laser-assisted immobilization of colloid silver nanoparticles on polyethyleneterephthalate

Science.gov (United States)

Siegel, Jakub; Lyutakov, Oleksiy; Polívková, Markéta; Staszek, Marek; Hubáček, Tomáš; Švorčík, Václav

2017-10-01

Immobilization of nanoobjects on the surface of underlying material belongs to current issues of material science. Such altered materials exhibits completely exceptional properties exploitable in a broad spectrum of industrially important applications ranging from catalysts up to health-care industry. Here we present unique approach for immobilization of electrochemically synthesized silver nanoparticles on polyethyleneterephthalate (PET) foil whose essence lies in physical incorporation of particles into thin polymer surface layer induced by polarized excimer laser light. Changes in chemical composition and surface structure of polymer after particle immobilization were recorded by wide range of analytical techniques such as ARXPS, EDX, RBS, AAS, Raman, ICP-MS, DLS, UV-vis, SEM, TEM, and AFM. Thorough analysis of both nanoparticles entering the immobilization step as well as modified PET surface allowed revealing the mechanism of immobilization process itself. Silver nanoparticles were physically embedded into a thin surface layer of polymer reaching several nanometers beneath the surface rather than chemically bonded to PET macromolecules. Laser-implanted nanoparticles open up new possibilities especially in the development of the next generation cell-conform antimicrobial coatings of polymeric materials, namely due to the considerable immobilization strength which is strong enough to prevent particle release into the surrounding environment.

Production of cellulase from immobilized Trichoderma reesei

International Nuclear Information System (INIS)

Kasai, Noboru; Tamada, Masao; Kumakura, Minoru

1989-05-01

This report completed the results that obtained on the study of the enzyme activity in the culture of immobilized Trichoderma reesei cells in flask scale (100ml) and bench scale (30l). In the flask scale culture, the batch and repeated batch culture were carried out, and in the bench scale culture, the batch, repeated batch and continuous culture were done by using a culture equipment that is an unit process of the bench scale test plant for saccharification of cellulosic wastes. The enzyme activity of the immobilized cells was higher than that of the intact cells in the flask scale culture and it was confirmed that the enzyme activity was not decreased on the repeated batch culture of six times even. In the bench scale culture, it was found that a optimum culture condition of the immobilized cells was not different from that of the free cells and the immobilized cells gave the enzyme solution with a high enzyme activity in the culture condition of 450rpm stirring speed and air supply of 0.1v/v/m above. The technique of the repeated batch and continuous culture for long times in bench scale without contamination was established. The enzyme activity of the immobilized cells in continuous culture became to be 85 % to that in batch culture and it was found that the enzyme solution with high enzyme activity was continuously obtained in the continuous culture for long times. (author)

Position of Immobilization After First-Time Traumatic Anterior Glenohumeral Dislocation: A Literature Review.

Science.gov (United States)

Gutkowska, Olga; Martynkiewicz, Jacek; Gosk, Jerzy

2017-07-15

Anterior glenohumeral dislocation affects about 2% of the general population during the lifetime. The incidence of traumatic glenohumeral dislocation ranges from 8.2 to 26.69 per 100 000 population per year. The most common complication is recurrent dislocation occurring in 17-96% of the patients. The majority of patients are treated conservatively by closed reduction and immobilization in internal rotation for 2-3 weeks. However, no clear conservative treatment protocol exists. Immobilization in external rotation can be considered an alternative. A range of external rotation braces are commercially available. The purpose of this work was to review the current literature on conservative management of glenohumeral dislocation and to compare the results of immobilization in internal and external rotation. A comprehensive literature search and review was performed using the keywords "glenohumeral dislocation", "shoulder dislocation", "immobilization", "external rotation", and "recurrent dislocation" in PubMed, MEDLINE, Cochrane Library, Scopus, and Google Scholar databases from their inceptions to May 2016. Three cadaveric studies, 6 imaging studies, 10 clinical studies, and 4 meta-analyses were identified. The total number of 734 patients were included in the clinical studies. Literature analysis revealed better coaptation of the labrum on the glenoid rim in external rotation in cadaveric and imaging studies. However, this tendency was not confirmed by lower redislocation rates or better quality of life in clinical studies. On the basis of the available literature, we cannot confirm the superiority of immobilization in external rotation after glenohumeral dislocation when compared to internal rotation. A yet-to-be-determined group of patients with specific labroligamentous injury pattern may benefit from immobilization in external rotation. Further studies are needed to identify these patients.

Lower limb immobilization device induced small setup errors in the radiotherapy.

Science.gov (United States)

Lu, Yuting; Ni, Xinye; Yu, Jingping; Ni, Xinchu; Sun, Zhiqiang; Wang, Jianlin; Sun, Suping; Wang, Jian

2018-04-01

The aim of this study was to design a lower limb immobilization device and investigate its clinical application in the radiotherapy of the lower limbs.Around 38 patients who underwent lower limb radiotherapy using the designed immobilization device were included in this study. The setup errors were calculated by comparison of the portal images and the simulator films or digital reconstructed radiographs (DRRs).From all 38 patients accomplished the radiotherapy using this device, 178 anteroposterior portal images and 178 lateral portal images were used for the analysis of the positional accuracy. Significant differences were observed in the setup error of the head-foot direction compared with the left-right direction (t = 3.404, P = .002) and the anterior-posterior directions (t = 3.188, P = .003). No statistical differences were identified in the setup error in the left-right direction and anterior-posterior direction (t = 0.497, P = .622).The use of the in-house designed lower limb immobilization device allowed for relatively small setup errors. Furthermore, it showed satisfactory accuracy and repeatability.

Immobilization of radioactive waste in glass matrices

International Nuclear Information System (INIS)

Wicks, G.G.

1978-01-01

A promising process for long-term management of high-level radioactive waste is to immobilize the waste in a borosilicate glass matrix. Among the most important criteria characterizing the integrity of the large-scale glass-waste forms are that they possess good chemical stability (including low leachability), thermal stability, mechanical integrity, and high radiation stability. Fulfillment of these criteria ensures the maximum margin of safety of glass-waste products, following solidification, handling, transportation, and long-term storage

Biosorption of uranium by Pseudomonas aeruginosa strain CSU immobilized in a novel matrix

International Nuclear Information System (INIS)

Hu, M.C.Z.; Reeves, M.

1997-01-01

A number of polymeric materials, including calcium alginate, polyacrylamide, polysulfone, and polyurethane, were evaluated as possible immobilization matrices for lyophilized biomass of P. aeruginoso CSU. Polyurethane-based materials such as hydrogel were identified as superior candidates for biomass immobilization. A novel polyurethane gel-bead fabrication technique was developed and successfully demonstrated at pilot-plant scale for producing mass qualities of spherical, uniform-size beads. The immobilized bacterial biomass was evaluated via the measurement of sorption isotherms and dynamics within a batch, stirred-tank reactor; and loading and elution behavior within a continuous, upflow, packed-bed columnar reactor. Sorption equilibrium and dynamics in a batch stirred tank were modeled with a pore-diffusion mass transfer model, by which a pore-diffusion coefficient was determined to be approximately 2.0 x 10 -6 cm 2 /s for uranyl ion transport through the polyurethane gel matrix. The biosorbent beads were regenerable with dilute (0.01-0.1 M) sodium carbonate solutions. Preliminary column breakthrough-elution studies indicated that P. aeruginosa CSU biomass immobilized within polyurethane gel beads was effective for removal of uranium from low-concentration, acidic wastewater. 35 refs., 9 figs., 4 tabs

Synthesis and Characterization of Magnetic Carriers Based on Immobilized Enzyme

Science.gov (United States)

Li, F. H.; Tang, N.; Wang, Y. Q.; Zhang, L.; Du, W.; Xiang, J.; Cheng, P. G.

2018-05-01

Several new types of carriers and technologies have been implemented to improve traditional enzyme immobilization in industrial biotechnology. The magnetic immobilized enzyme is a kind of new method of enzyme immobilization developed in recent years. An external magnetic field can be used to control the motion mode and direction of immobilized enzyme, and to improve the catalytic efficiency of immobilized enzyme. In this paper, Fe3O4-CaCO3-PDA complex and CaCO3/Fe3O4 composite modified by PEI were prepared. The results show that the morphology of Fe3O4-CaCO3-PDA complex formation is irregular, while the morphology of CaCO3/Fe3O4 composite modified by PEI is regular and has a porous structure.

An Efficient, Recyclable, and Stable Immobilized Biocatalyst Based on Bioinspired Microcapsules-in-Hydrogel Scaffolds.

Science.gov (United States)

Zhang, Shaohua; Jiang, Zhongyi; Shi, Jiafu; Wang, Xueyan; Han, Pingping; Qian, Weilun

2016-09-28

Design and preparation of high-performance immobilized biocatalysts with exquisite structures and elucidation of their profound structure-performance relationship are highly desired for green and sustainable biotransformation processes. Learning from nature has been recognized as a shortcut to achieve such an impressive goal. Loose connective tissue, which is composed of hierarchically organized cells by extracellular matrix (ECM) and is recognized as an efficient catalytic system to ensure the ordered proceeding of metabolism, may offer an ideal prototype for preparing immobilized biocatalysts with high catalytic activity, recyclability, and stability. Inspired by the hierarchical structure of loose connective tissue, we prepared an immobilized biocatalyst enabled by microcapsules-in-hydrogel (MCH) scaffolds via biomimetic mineralization in agarose hydrogel. In brief, the in situ synthesized hybrid microcapsules encapsulated with glucose oxidase (GOD) are hierarchically organized by the fibrous framework of agarose hydrogel, where the fibers are intercalated into the capsule wall. The as-prepared immobilized biocatalyst shows structure-dependent catalytic performance. The porous hydrogel permits free diffusion of glucose molecules (diffusion coefficient: ∼6 × 10(-6) cm(2) s(-1), close to that in water) and retains the enzyme activity as much as possible after immobilization (initial reaction rate: 1.5 × 10(-2) mM min(-1)). The monolithic macroscale of agarose hydrogel facilitates the easy recycling of the immobilized biocatalyst (only by using tweezers), which contributes to the nonactivity decline during the recycling test. The fiber-intercalating structure elevates the mechanical stability of the in situ synthesized hybrid microcapsules, which inhibits the leaching and enhances the stability of the encapsulated GOD, achieving immobilization efficiency of ∼95%. This study will, therefore, provide a generic method for the hierarchical organization of (bio

Immobilization of enzymes by radiation-induced polymerization of glass-forming monomers

International Nuclear Information System (INIS)

Yoshida, M.; Kumakura, M.; Kaetsu, I.

1979-01-01

The effect of cooling rate of a monomeric system on the porosity and activity of an immobilized enzyme prepared by radiation-induced polymerization of 2-hydroxyethyl methacrylate at low temperatures has been studied. Slow cooling gave the same effect on porosity of the polymer as decreasing the monomer concentration. A glass-forming solvent such as diethylene glycol was added to water to study the effect of the supercooling tendency of the solvent. Addition of diethylene glycol decreased porosity and also enzymic activity. Water was replaced by the miscible solvent p-dioxane and the immiscible solvent n-decane in order to clarify the effect of solvent. p-Dioxane had a similar effect to water on the relation between the monomer concentration, porosity and activity. On the other hand, polymer prepared from the system containing n-decane showed different immobilization properties owing to the presence of independent pores in the matrix. (author)

Evaluation of co-immobilized lactobacillus delbrueckii with porous particles for lactic acid production

Energy Technology Data Exchange (ETDEWEB)

Wang, H.; Seki, M.; Furusaki, S. [The University of Tokyo, Tokyo (Japan)

1996-02-01

Lactic acid production using co-immobilized L.defbrveckii with porous particles has been studied. The effect of co-immobilization with porous particles was verified by measuring the variations of both overall production rate of lactic acid and effective diffusion coefficient in the co-immobilized gel. The effective diffusion coefficient decreased with increasing cell concentration in the co-immobilized gel. However, in the high cell density regimes, the effective diffusion coefficient in co-immobilized gel was higher than that without co-immobilized porous particles. The optimal volume fraction of porous particles in the co-immobilizing gel beads leas estimated experimentally at about 10%(v/v). An approximately 30% increase of the overall production rate was obtained compared to the control culture. Mathematical analysis showed that by co-immobilizing cells with porous particles, the steady-state concentration profiles of proton and undissociated lactic acid changed favorably inside the gel beads. The result indicates that co-immobilization with porous particles is a useful method to improve fermentation efficiency in processes using immobilized cells. 19 refs., 8 figs.

Immobilization of the white-rot fungus Anthracophyllum discolor to degrade the herbicide atrazine.

Science.gov (United States)

Elgueta, S; Santos, C; Lima, N; Diez, M C

2016-12-01

Herbicides cause environmental concerns because they are toxic and accumulate in the environment, food products and water supplies. There is a need to develop safe, efficient and economical methods to remove them from the environment, often by biodegradation. Atrazine is such herbicide. White-rot fungi have the ability to degrade herbicides of potential utility. This study formulated a novel pelletized support to immobilize the white-rot fungus Anthracophyllum discolor to improve its capability to degrade the atrazine using a biopurification system (BS). Different proportions of sawdust, starch, corn meal and flaxseed were used to generate three pelletized supports (F1, F2 and F3). In addition, immobilization with coated and uncoated pelletized supports (CPS and UPS, respectively) was assessed. UPS-F1 was determined as the most effective system as it provided high level of manganese peroxidase activity and fungal viability. The half-life (t 1/2 ) of atrazine decreased from 14 to 6 days for the control and inoculated samples respectively. Inoculation with immobilized A. discolor produced an increase in the fungal taxa assessed by DGGE and on phenoloxidase activity determined. The treatment improves atrazine degradation and reduces migration to surface and groundwater.

Electrically conductive, immobilized bioanodes for microbial fuel cells

International Nuclear Information System (INIS)

Ganguli, R; Dunn, B

2012-01-01

The power densities of microbial fuel cells with yeast cells as the anode catalyst were significantly increased by immobilizing the yeast in electrically conductive alginate electrodes. The peak power densities measured as a function of the electrical conductivity of the immobilized electrodes show that although power increases with rising electrical conductivity, it tends to saturate beyond a certain point. Changing the pH of the anode compartment at that point seems to further increase the power density, suggesting that proton transport limitations and not electrical conductivity will limit the power density from electrically conductive immobilized anodes. (paper)

Immobilization of Wyoming bears using carfentanil and xylazine.

Science.gov (United States)

Kreeger, Terry J; Bjornlie, Dan; Thompson, Dan; Clapp, Justin; Clark, Colby; Hansen, Cole; Huizenga, Matt; Lockwood, Sam

2013-07-01

Seven grizzly (Ursus arctos; four male, three female) and three black (Ursus americanus; two male, one female) bears caught in culvert traps or leg snares were immobilized in northwestern Wyoming with carfentanil and xylazine at doses, respectively, of 0.011 ± 0.001 and 0.12 ± 0.01 mg/kg for grizzly bears and 0.014 ± 0.002 and 0.15 ± 0.04 mg/kg for black bears. These drugs were antagonized with 1 mg/kg naltrexone and 2 mg/kg tolazoline. Induction and recovery times, respectively, were 4.3 ± 0.5 and 7.1 ± 0.8 min for grizzly bears and 5.2 ± 0.4 and 9.1 ± 2.2 min for black bears. Inductions were smooth and uneventful. Recoveries were characterized initially by increased respiration followed by raising of the head, which quickly led to a full recovery, with the bears recognizing and avoiding humans and moving away, maneuvering around obstacles. All bears experienced respiratory depression, which did not significantly improve with supplemental oxygen on the basis of pulse oximetry (P=0.56). Rectal temperatures were normothermic. Carfentanil-xylazine immobilization of bears provided significant advantages over other drug regimens, including small drug volumes, predictable inductions, quick and complete recoveries, and lower costs. On the basis of these data, both grizzly and black bears can be immobilized effectively with 0.01 mg/kg carfentanil and 0.1 mg/kg xylazine.

Removal of nitrate using Paracoccus sp. YF1 immobilized on bamboo carbon

Energy Technology Data Exchange (ETDEWEB)

Liu, Yan; Gan, Li [School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province (China); Chen, Zuliang, E-mail: Zuliang.chen@unisa.edu.au [School of Environmental Science and Engineering, Fujian Normal University, Fuzhou 350007, Fujian Province (China); Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of Environments, Mawson Lakes, SA 5095 (Australia); Megharaj, Mallavarapu; Naidu, Ravi [Centre for Environmental Risk Assessment and Remediation, University of South Australia, Mawson Lakes, SA 5095 (Australia); Cooperative Research Centre for Contamination Assessment and Remediation of Environments, Mawson Lakes, SA 5095 (Australia)

2012-08-30

Highlights: Black-Right-Pointing-Pointer Paracoccus sp. immobilized on bamboo carbon used for the denitrification. Black-Right-Pointing-Pointer The rate of denitrification increased using the immobilized cells. Black-Right-Pointing-Pointer 99.8% denitrification was maintained after 10-cycle reuse. Black-Right-Pointing-Pointer Demonstrating an excellent reusability and a potential technique. - Abstract: Paracoccus sp. strain YF1 immobilized on bamboo carbon was developed for the denitrification. The results show that denitrification was significantly improved using immobilized cells compared to that of free cells, where denitrification time decreased from 24 h (free cells) to 15 h (immobilized cells). The efficiency of denitrification increased from 4.57 mg/(L h) (free cells) to 6.82 mg/(L h) (immobilized cells). Kinetics studies suggest that denitrification by immobilized YF1 cells fitted well to the zero-order model. Scanning electron microscopy (SEM) demonstrated that firstly, the bacteria became stable on the inside and exterior of the bamboo carbon particles and secondly, they formed biofilm after adhesion. Various factors and their influences on biological denitrification were investigated, namely temperature, pH, initial nitrate concentrations and carbon sources. The immobilized cells exhibited more nitrate removal at various conditions compared to free cells since bamboo carbon as a carrier protects cells against changes in environmental conditions. Denitrification using the YF1 immobilized in bamboo carbon was also maintained 99.8% after the tenth cycle reuse, thus demonstrating excellent reusability. Finally, wastewater was treated using the immobilized cells and the outcome was that nitrogen was completely removed by bamboo-immobilized YF1.

Removal of nitrate using Paracoccus sp. YF1 immobilized on bamboo carbon

International Nuclear Information System (INIS)

Liu, Yan; Gan, Li; Chen, Zuliang; Megharaj, Mallavarapu; Naidu, Ravi

2012-01-01

Highlights: ► Paracoccus sp. immobilized on bamboo carbon used for the denitrification. ►The rate of denitrification increased using the immobilized cells. ► 99.8% denitrification was maintained after 10-cycle reuse. ► Demonstrating an excellent reusability and a potential technique. - Abstract: Paracoccus sp. strain YF1 immobilized on bamboo carbon was developed for the denitrification. The results show that denitrification was significantly improved using immobilized cells compared to that of free cells, where denitrification time decreased from 24 h (free cells) to 15 h (immobilized cells). The efficiency of denitrification increased from 4.57 mg/(L h) (free cells) to 6.82 mg/(L h) (immobilized cells). Kinetics studies suggest that denitrification by immobilized YF1 cells fitted well to the zero-order model. Scanning electron microscopy (SEM) demonstrated that firstly, the bacteria became stable on the inside and exterior of the bamboo carbon particles and secondly, they formed biofilm after adhesion. Various factors and their influences on biological denitrification were investigated, namely temperature, pH, initial nitrate concentrations and carbon sources. The immobilized cells exhibited more nitrate removal at various conditions compared to free cells since bamboo carbon as a carrier protects cells against changes in environmental conditions. Denitrification using the YF1 immobilized in bamboo carbon was also maintained 99.8% after the tenth cycle reuse, thus demonstrating excellent reusability. Finally, wastewater was treated using the immobilized cells and the outcome was that nitrogen was completely removed by bamboo-immobilized YF1.

Immobilization Technologies in Probiotic Food Production

Directory of Open Access Journals (Sweden)

Gregoria Mitropoulou

2013-01-01

Full Text Available Various supports and immobilization/encapsulation techniques have been proposed and tested for application in functional food production. In the present review, the use of probiotic microorganisms for the production of novel foods is discussed, while the benefits and criteria of using probiotic cultures are analyzed. Subsequently, immobilization/encapsulation applications in the food industry aiming at the prolongation of cell viability are described together with an evaluation of their potential future impact, which is also highlighted and assessed.

Immobilization patterns and dynamics of acetate-utilizing methanogens in sterile granular sludge from upflow anaerobic sludge blanket (UASB) reactors

DEFF Research Database (Denmark)

Schmidt, Jens Ejbye; Ahring, Birgitte Kiær

1999-01-01

Sterile granular sludge was inoculated with either Methanosarcina mazeii S-6, Methanosaeta concilii GP-6, or both species in acetate-fea upflow anaerobic sludge blanket (UASB) reactors to investigate the immobilization patterns and dynamics of aceticlastic methanogens in granular sludge. After......, but where the acetate concentration was low this strain was immobilized on support material as single cells or small clumps, The data clearly show that the two aceticlastic methanogens immobilize differently in UASB systems, depending on the conditions found throughout the UASB reactor....

A multilayered polyurethane foam technique for skin graft immobilization.

Science.gov (United States)

Nakamura, Motoki; Ito, Erika; Kato, Hiroshi; Watanabe, Shoichi; Morita, Akimichi

2012-02-01

Several techniques are applicable for skin graft immobilization. Although the sponge dressing is a popular technique, pressure failure near the center of the graft is a weakness of the technique that can result in engraftment failure. To evaluate the efficacy of a new skin graft immobilization technique using multilayered polyurethane foam in vivo and in vitro. Twenty-six patients underwent a full-thickness skin graft. Multiple layers of a hydrocellular polyurethane foam dressing were used for skin graft immobilization. In addition, we created an in vitro skin graft model that allowed us to estimate immobilization pressure at the center and edges of skin grafts of various sizes. Overall mean graft survival was 88.9%. In the head and neck region (19 patients), mean graft survival was 93.6%. Based on the in vitro outcomes, this technique supplies effective pressure (skin graft. This multilayered polyurethane foam dressing is simple, safe, and effective for skin graft immobilization. © 2011 by the American Society for Dermatologic Surgery, Inc. Published by Wiley Periodicals, Inc.

Immobilization of Trichoderma reesei cells by radiation polymerization

International Nuclear Information System (INIS)

Kumakura, M.; Kaetsu, I.

1983-01-01

Trichoderma reesei cells were immobilized by radiation polymerization 2-hydroxyethyl acrylate monomer at low temperature. Cellulase production resulting from the growth of the cells in the porous polymer matrix of immobilized cell composites was confirmed by measuring the cellulase activity and pH during the culture. (orig.)

Laccase Immobilization by Chelated Metal Ion Coordination Chemistry

Directory of Open Access Journals (Sweden)

Qingqing Wang

2014-09-01

Full Text Available In this work, amidoxime polyacrylonitrile (AOPAN nanofibrous membrane was prepared by a reaction between PAN nanofibers and hydroxylamine hydrochloride. The AOPAN nanofibrous membranes were used for four metal ions (Fe3+, Cu2+, Ni2+, Cd2+ chelation under different conditions. Further, the competition of different metal ions coordinating with AOPAN nanofibrous membrane was also studied. The AOPAN chelated with individual metal ion (Fe3+, Cu2+, Ni2+, Cd2+ and also the four mixed metal ions were further used for laccase (Lac immobilization. Compared with free laccase, the immobilized laccase showed better resistance to pH and temperature changes as well as improved storage stability. Among the four individual metal ion chelated membranes, the stability of the immobilized enzymes generally followed the order as Fe–AOPAN–Lac > Cu–AOPAN–Lac > Ni–AOPAN–Lac > Cd–AOPAN–Lac. In addition, the immobilized enzyme on the carrier of AOPAN chelated with four mixed metal ions showed the best properties.

Preparation and Properties of Urease Immobilized onto Glutaraldehyde Cross-linked Chitosan Beads

Institute of Scientific and Technical Information of China (English)

Zu Pei LIANG; Ya Qing FENG; Shu Xian MENG; Zhi Yan LIANG

2005-01-01

Urease was immobilized onto the glutaraldehyde cross-linked chitosan beads that were prepared under microwave irradiation. The activity and the yield of activity of immobilized urease was 10.83 U/g B and 47.7%, respectively. The conditions of urease immobilization were optimized. The properties of the immobilized urease were investigated and compared with that of the free enzyme.

Permitting plan for the immobilized low-activity waste project

International Nuclear Information System (INIS)

Deffenbaugh, M.L.

1997-01-01

This document addresses the environmental permitting requirements for the transportation and interim storage of the Immobilized Low-Activity Waste (ILAW) produced during Phase 1 of the Hanford Site privatization effort. Tri-Party Agreement (TPA) Milestone M-90 establishes a new major milestone, and associated interim milestones and target dates, governing acquisition and/or modification of facilities necessary for: (1) interim storage and disposal of Tank Waste Remediation Systems (TWRS) immobilized low-activity tank waste (ILAW) and (2) interim storage of TWRS immobilized HLW (IHLW) and other canistered high-level waste forms. Low-activity waste (LAW), low-level waste (LLW), and high-level waste (HLW) are defined by the TWRS, Hanford Site, Richland, Washington, Final Environmental Impact Statement (EIS) DOE/EIS-0189, August 1996 (TWRS, Final EIS). By definition, HLW requires permanent isolation in a deep geologic repository. Also by definition, LAW is ''the waste that remains after separating from high-level waste as much of the radioactivity as is practicable that when solidified may be disposed of as LLW in a near-surface facility according to the NRC regulations.'' It is planned to store/dispose of (ILAW) inside four empty vaults of the five that were originally constructed for the Group Program. Additional disposal facilities will be constructed to accommodate immobilized LLW packages produced after the Grout Vaults are filled. The specifications for performance of the low-activity vitrified waste form have been established with strong consideration of risk to the public. The specifications for glass waste form performance are being closely coordinated with analysis of risk. RL has pursued discussions with the NRC for a determination of the classification of the Hanford Site's low-activity tank waste fraction. There is no known RL action to change law with respect to onsite disposal of waste

Hydrolysis of whey lactose by immobilized β-galactosidase in a bioreactor with a spirally wound membrane.

Science.gov (United States)

Vasileva, Nastya; Ivanov, Yavor; Damyanova, Stanka; Kostova, Iliana; Godjevargova, Tzonka

2016-01-01

The β-galactosidase was covalently immobilized onto a modified polypropylene membrane, using glutaraldehyde. The optimal conditions for hydrolysis of lactose (4.7%) by immobilized β-galactosidase in a batch process were determined 13.6 U enzyme activity, 40°C, pH 6.8 and 10h. The obtained degree of hydrolysis was compared with results received by a free enzyme. It was found, that the lactose hydrolysis by an immobilized enzyme was 1.6 times more effective than the lactose hydrolysis by a free enzyme. It was determined that the stability of the immobilized enzyme was 2 times higher in comparison with the stability of free enzyme. The obtained immobilized system β-galactosidase/polypropylene membrane was applied to produce glucose-galactose syrup from waste whey. The whey characteristics and the different preliminary treatments of the whey were investigated. Then the whey lactose hydrolysis in a bioreactor by an immobilized enzyme on a spirally wound membrane was performed. The optimal membrane surface and the optimal flow rate of the whey through the membrane module were determined, respectively 100 cm(2) and 1.0 mL min(-1). After 10h, the degree of lactose hydrolysis was increased to 91%. The operation stability was studied. After 20th cycle the yield of bioreactor was 69.7%. Copyright © 2015 Elsevier B.V. All rights reserved.

Lipase immobilized on the hydrophobic polytetrafluoroethene membrane with nonwoven fabric and its application in intensifying synthesis of butyl oleate.

Science.gov (United States)

Wang, Shu-Guang; Zhang, Wei-Dong; Li, Zheng; Ren, Zhong-Qi; Liu, Hong-Xia

2010-11-01

The synthesis of butyl oleate was studied in this paper with immobilized lipase. Five types of membrane were used as support to immobilize Rhizopus arrhizus lipase by following a procedure combining filtration and protein cross-linking. Results showed that hydrophobic polytetrafluoroethene membrane with nonwoven fabric (HO-PTFE-NF) was the favorite choice in terms of higher protein loading, activity, and specific activity of immobilized lipase. The factors including solvent polarity, lipase dosage, concentration, and molar ratio of substrate and temperature were found to have significant influence on conversion. Results showed that hexane (logP = 3.53) was a favorable solvent for the biosynthesis of butyl oleate in our studies. The optimal conditions were experimentally determined of 50 U immobilized lipase, molar ratio of oleic acid to butanol of 1.0, substrate concentration of 0.12 mol/L, temperature of 37 °C, and reaction time of 2 h. The conversion was beyond 91% and decreased slightly after 18 cycles. Lipase immobilization can improve the conversion and the repeated use of immobilized lipase relative to free lipase.

Characteristics of immobilized aminoacylase from Aspergillus oryzae on macroporous copolymers.

Science.gov (United States)

He, B L; Jiang, P; Qiu, Y B

1990-01-01

Aminoacylase from Aspergillus oryzae was adsorbed on functionallized macroporous copolymers where the enzyme showed excellent catalyzing activity and operation stability. Various factors which effect the activity of the immobilized aminoacylase such as temperature, pH and ionic strength were investigated. The continuous operation of the enzyme immobilized on macroporous copolymers was compared with that of the enzyme immobilized on DEAE-Sephadex.

Studies on the immobilization of biofunctional components by radiation polymerization and their applications

International Nuclear Information System (INIS)

Kaetsu, I.; Kumakura, M.; Fujimura, T.; Yoshida, M.; Asano, M.; Kasai, N.; Tamada, M.

1986-01-01

The recent progress on the studies of immobilization of various biofunctional components mainly by means of radiation polymerization as well as their practical applications to biomedical and biochemical fields were reviewed. The immobilization of drugs for the controlled release and targetting, the immobilization of antigens and antibodies for the immunodiagnosis, and the immobilization of microorganisms and tissue cells for the cell culture and the biomass conversion were the main topics in this review. The new findings on the enhanced immobilization methods and the polymeric carriers for immobilization were also attached. (author)

Short-term immobilization influences use-dependent cortical plasticity and fine motor performance.

Science.gov (United States)

Opie, George M; Evans, Alexandra; Ridding, Michael C; Semmler, John G

2016-08-25

Short-term immobilization that reduces muscle use for 8-10h is known to influence cortical excitability and motor performance. However, the mechanisms through which this is achieved, and whether these changes can be used to modify cortical plasticity and motor skill learning, are not known. The purpose of this study was to investigate the influence of short-term immobilization on use-dependent cortical plasticity, motor learning and retention. Twenty-one adults were divided into control and immobilized groups, both of which underwent two experimental sessions on consecutive days. Within each session, transcranial magnetic stimulation (TMS) was used to assess motor-evoked potential (MEP) amplitudes, short- (SICI) and long-interval intracortical inhibition (LICI), and intracortical facilitation (ICF) before and after a grooved pegboard task. Prior to the second training session, the immobilized group underwent 8h of left hand immobilization targeting the index finger, while control subjects were allowed normal limb use. Immobilization produced a reduction in MEP amplitudes, but no change in SICI, LICI or ICF. While motor performance improved for both groups in each session, the level of performance was greater 24-h later in control, but not immobilized subjects. Furthermore, training-related MEP facilitation was greater after, compared with before, immobilization. These results indicate that immobilization can modulate use-dependent plasticity and the retention of motor skills. They also suggest that changes in intracortical excitability are unlikely to contribute to the immobilization-induced modification of cortical excitability. Copyright © 2016. Published by Elsevier Ltd.

Immobilization of Gibberella fujikuroi cells with carriers modified by radiation polymerization

International Nuclear Information System (INIS)

Lu Zhaoxin; Xie Zhongchuan; Wei Qijiang

1994-01-01

Gibberella fujikuroi cells were immobilized on modified carriers (gauze) by using the radiation polymerization technique. The mycelium was firmly adhered to the surface of fibril covered with hydrophobic polymer, poly (diethylene glycol dimethyl acrylate) and hydrophobic-hydrophilic copolymer poly (diethylene glycol dimethyl acrylate-sodium acrylate), but it was not immobilized onto the polyethylene net, which has a similar network structure to that of the modified carrier. The weight of immobilized cells was affected by covered polymer. Gibberellic acid productivity in immobilized cells was similar to that of free cells, and the immobilized cells was of good stability. A optimum culture condition for gibberellic acid production was at pH 5.5 and under 20 ∼ 30 degree C

Preparation of tubular urease immobilized on the inner wall of glass tube by radiation-polymerization

Energy Technology Data Exchange (ETDEWEB)

Tanaka, Y; Hayashi, T; Kawashima, K [National Food Research Inst., Yatabe, Ibaraki (Japan); Oka, O

1981-03-01

A method to prepare immobilized urease on the inner wall of a glass tube by radiation-polymerization under frozen state was investigated. As a part of a continuous flow analyzer, i.w.. Technicon Auto Analyzer II, the immobilized urease tube of 1 cm length was set and used for the routine determination of urea. This flow-through system could measure urea concentration of up to 30 mM at rate of 30 samples per hour. The system were possible to assay 2000 to 3000 samples, continuously in practice. The activity of the urease tube stored in a refrigerator maintained 94% of the initial activity after 115 days.

Preparation of tubular urease immobilized on the inner wall of glass tube by radiation-polymerization

International Nuclear Information System (INIS)

Tanaka, Yoshikazu; Hayashi, Toru; Kawashima, Koji; Oka, Osamu.

1981-01-01

A method to prepare immobilized urease on the inner wall of a glass tube by radiation-polymerization under frozen state was investigated. As a part of a continuous flow analyzer, i.w.. Technicon Auto Analyzer II, the immobilized urease tube of 1 cm length was set and used for the routine determination of urea. This flow-through system could measure urea concentration of up to 30 mM at rate of 30 samples per hour. The system were possible to assay 2000 to 3000 samples, continuously in practice. The activity of the urease tube stored in a refrigirator maintained 94% of the initial activity after 115 days. (author)

Chemical immobilization of chimpanzees (Pan troglodytes) using a combination of detomidine and ketamine.

Science.gov (United States)

Melis, Sanne; Schauvliege, Stijn; van Bolhuis, Hester; Hoyer, Mark; Gasthuys, Frank

2012-09-01

To determine if a combination of detomidine and ketamine can be used for effective chemical immobilization of chimpanzees. Observational study. Twenty-one adult captive chimpanzees (12 males, nine females), age 8-46 years, weighing 40.4-68.4 kg. The chimpanzees were immobilized with intramuscular (IM) detomidine and ketamine by a darting system. Based on estimated weights, doses administered were 50 μg kg(-1) detomidine and 4 mg kg(-1) ketamine in groups 1 and 2, and 60 μg kg(-1) and 5 mg kg(-1) respectively in group 3. Eight minutes in group 1 and 15 minutes in groups 2 and 3 were allowed from the time of apparent immobilization before removing the animals from their enclosures. Body temperature, arterial haemoglobin saturation and pulse rate were measured. The time from injection to induction (recumbency and absence of voluntary movement), total anaesthetic and recovery times (with or without atipamezole) were recorded. Immobilization occurred within 5 minutes after darting in most animals. Early handling of the chimpanzees often resulted in arousal and required further doses of ketamine IM. Most animals were hypoxaemic and hypothermic. Occasionally, bradycardia was observed. Atipamezole resulted in an acceptable quality of recovery 10 minutes after IM injection. The duration of immobilization varied widely when no antagonist was administered. The combination detomidine (60 μg kg(-1) ) and ketamine (5-6 mg kg(-1) ) can be used for the immobilization of chimpanzees for non- to minimally invasive procedures. A period of 15 minutes should be allowed before handling to avoid unwanted arousal. Oxygen administration is recommended to reduce hypoxaemia. Administration of atipamezole is justified to hasten recovery. © 2012 The Authors. Veterinary Anaesthesia and Analgesia. © 2012 Association of Veterinary Anaesthetists and the American College of Veterinary Anesthesiologists.

Reducing the Incidence of Cast-related Skin Complications in Children Treated With Cast Immobilization.

Science.gov (United States)

Difazio, Rachel L; Harris, Marie; Feldman, Lanna; Mahan, Susan T

2017-12-01

Cast immobilization remains the mainstay of pediatric orthopaedic care, yet little is known about the incidence of cast-related skin complications in children treated with cast immobilization. The purposes of this quality improvement project were to: (1) establish a baseline rate of cast-related skin complications in children treated with cast immobilization, (2) identify trends in children who experienced cast-related skin complications, (3) design an intervention aimed at decreasing the rate of cast-related skin complications, and (4) determine the effectiveness of the intervention. A prospective interrupted time-series design was used to determine the incidence of cast-related skin complications overtime and compare the rates of skin complications before and after an intervention designed to decrease the incidence of cast-related heel complications. All consecutive patients who were treated with cast immobilization from September 2012 to September 2014 were included. A cast-related skin complications data collection tool was used to capture all cast-related skin complications. A high rate of heel events was noted in our preliminary analysis and an intervention was designed to decrease the rate of cast-related skin complications, including the addition of padding during casting and respective provider education. The estimated cast-related skin events rate for all patients was 8.9 per 1000 casts applied. The rate for the total preintervention sample was 13.6 per 1000 casts which decreased to 6.6 in the postintervention sample. When examining the heel-only group, the rate was 17.1 per 1000 lower extremity casts applied in the preintervention group and 6.8 in the postintervention group. Incorporating padding to the heel of lower extremity cast was an effective intervention in decreasing the incidence of cast-related skin complications in patients treated with cast immobilization. Level II.

Surface Immobilization of Human Arginase-1 with an Engineered Ice Nucleation Protein Display System in E. coli.

Directory of Open Access Journals (Sweden)

Zhen Zhang

Full Text Available Ice nucleation protein (INP is frequently used as a surface anchor for protein display in gram-negative bacteria. Here, MalE and TorA signal peptides, and three charged polypeptides, 6×Lys, 6×Glu and 6×Asp, were anchored to the N-terminus of truncated INP (InaK-N to improve its surface display efficiency for human Arginase1 (ARG1. Our results indicated that the TorA signal peptide increased the surface translocation of non-protein fused InaK-N and human ARG1 fused InaK-N (InaK-N/ARG1 by 80.7% and 122.4%, respectively. Comparably, the MalE signal peptide decreased the display efficiencies of both the non-protein fused InaK-N and InaK-N/ARG1. Our results also suggested that the 6×Lys polypeptide significantly increased the surface display efficiency of K6-InaK-N/ARG1 by almost 2-fold, while also practically abolishing the surface translocation of non-protein fused InaK-N, indicating the interesting roles of charged polypeptides in bacteria surface display systems. Cell surface-immobilized K6-InaK-N/ARG1 presented an arginase activity of 10.7 U/OD600 under the optimized conditions of 40°C, pH 10.0 and 1 mM Mn2+, which could convert more than 95% of L-Arginine (L-Arg to L-Ornithine (L-Orn in 16 hours. The engineered InaK-Ns expanded the INP surface display system, which aided in the surface immobilization of human ARG1 in E. coli cells.

Immobilization of periodate oxidized invertase by adsorption on sepiolite

Directory of Open Access Journals (Sweden)

RADIVOJE M. PRODANOVIC

2003-11-01

Full Text Available Periodate oxidized invertase was immobilized by adsorption on sepiolite. The obtained immobilized enzyme was more resistant to washing out by concentrated salt solution, and had an eight times higher half-life at 60ºC than adsorbed native invertase. In packed bed reactor 50 % conversion of 500 g/dm3 sucrose at 40ºC and a flow rate of 1 bv/h was achieved. The specific productivity of the immobilized invertase was 0.187 kg/dm3/h.

Catalytic Properties and Immobilization Studies of Catalase from Malva sylvestris L.

Directory of Open Access Journals (Sweden)

G. Arabaci

2013-01-01

Full Text Available Catalase was partially purified from Malva sylvestris L. and immobilized onto chitosan. Then, its catalytic properties were investigated. (NH42SO4 precipitation and dialysis were performed in the extracted enzyme. Further purification was performed with sephadex G-200 column. Kinetic studies of the purified enzyme activity were measured and characterized. The inhibitory effects of KCN, NaN3, CuSO4, and EDTA on M. sylvestris L. catalase activity were observed except NaCl. Furthermore, M. sylvestris L. catalase was immobilized covalently with glutaraldehyde onto chitosan particles. The pH and temperature optima as well as the changes in the kinetics (Km, Vmax of the immobilized and free M. sylvestris L. catalase were determined. The Km value for immobilized catalase (23.4 mM was higher than that of free enzyme (17.6 mM. Optimum temperature was observed higher than that of the free enzyme. The optimum pH was the same for both free and immobilized catalases (pH 7.50. Immobilized catalase showed higher storage and thermal stabilities than free catalases. Free catalase lost all its activity within 60 days whereas immobilized catalase lost 45% of its activity during the same incubation period at 4°C. The remaining immobilized catalase activity was about 70% after 8 cycles of batch operations.

Central nervous adaptations following 1 week of wrist and hand immobilization

DEFF Research Database (Denmark)

Lundbye-Jensen, Jesper; Nielsen, Jens Bo

2008-01-01

in relation to one week of immobilization of the non-dominant wrist and hand and a corresponding period of recovery in 10 able-bodied volunteers. Following immobilization maximal voluntary contraction torque (MVC) decreased and the variability of submaximal static contractions increased significantly without...... (MEPs) elicited by transcranial magnetic stimulation (TMS). Corticomuscular coherence measures were derived from EEG and EMG obtained during static contractions. Following immobilization corticomuscular coherence in the 15-35 Hz range associated with maximum negative cumulant values at lags...... motor cortex and spinal motoneuronal activity following immobilization. Key words: Plasticity, Immobilization, Motor Control....

Bed Rest and Immobilization: Risk Factors for Bone Loss

Science.gov (United States)

... Risk Factors for Bone Loss Bed Rest and Immobilization: Risk Factors for Bone Loss Like muscle, bone ... complications of pregnancy; and those who are experiencing immobilization of some part of the body because of ...

Characterization of cellulose acetate micropore membrane immobilized acylase I.

Science.gov (United States)

Guo, Yong-Sheng; Wang, Jie; Song, Xi-Jin

2004-12-01

This paper describes an innovative method for the immobilization of acylase I, which was entrapped into the CA-CTA micropore membrane. The most suitable casting solutions proportion for immobilizing the enzyme was obtained through orthogonal experiment. Properties of the enzyme membrane were investigated and compared with those of free enzyme and blank membrane. The thermal stability and pH stability of the enzyme inside the membrane were changed by immobilization. The optimum pH was found to be 6.0, which changes 1.0 unit compared with that of free acylase I. The optimum temperature was found to be about 90 degrees C, which is higher than that of free acylase I (60 degrees C). Experimental results showed that immobilization had effects on the kinetic parameters of acylase I.

Studies of the immobilization of enzymes and microorganism pt.1

International Nuclear Information System (INIS)

Kim, S.K.

1979-01-01

A new method of immobilization of glucose oxidase by the aerobic gamma radiation of synthetic monomers was developed. The radiocopolymerization was conducted aerobically at -70 to-80 degC with the mixture of several polyfunctional esters, acrylates and native enzyme. The retained activity of immobilized glucoseoxidase was about 50 to 55% when a NK 23G ester, acrylamide-bis and water mixture (1:1:2) in cold toluene treated with 450 Krad of gamma radiation. The radiation dose did not influence significantly to the enzyme activity. The solvents used to prepare the beads of glucose oxidase and monomers were toluene, n-hexane, petoleum ether and chloroform. 0.05M tris-gycerol(pH 7.0) was a more suitable buffer solution for immobilizing the enzyme than was 0.02M phosphate. Immobilization of glucose oxidase shifted the optimum pH for its reaction from 6.0 to 6.5. The pH profile for the immobilized enzyme showed a broad range of optimum activity while the native enzyme gave a sharp pick for its optimum pH value. The immobilized enzyme reaction temperature was at the range of 30-40 degreesC. (Author)

Adsorption recovery of thorium(IV) by Myrica rubra tannin and larch tannin immobilized onto collagen fibres

International Nuclear Information System (INIS)

Xuepin Liao; Li Li; Bi Shi

2004-01-01

Novel adsorbents which can concentrate Th(IV) in aqueous solution were prepared by immobilizing Myrica rubra tannin and larch tannin onto collagen fibre matrices. The adsorption capacities of the immobilized tannins to Th(IV) are related to temperature and pH value of the adsorption process. For example, when the initial concentration of Th(IV) was 116.0 mg x l -1 and the immobilized tannin was 100 mg, the adsorption capacities of immobilized Myrica rubra tannin and larch tannin were 55.98 mg Th(IV) x g -1 and 13.19 mg Th(IV) x g -1 , respectively at 303 K, and 73.67 mg Th(IV) x g -1 and 18.19 mg Th(IV) x g -1 at 323 K. It was also found that the higher adsorption capacity was obtained at higher pH value. The adsorption equilibrium data of the immobilized tannins for Th(IV) can be well fitted by the Langmuir model and the mechanism of the adsorption was found to be a chemical adsorption. In general, the adsorption capacity of immobilized Myrica rubra tannin to Th(IV) is significantly higher than that of immobilized larch tannin, probably due to the fact that the B ring of Myrica rubra tannin has a pyrogallol structure which has higher reaction activity with metal ions. The breakthrough point of the adsorption column of immobilized Myrica rubra tannin was at 33 bed volumes for the experimental system. The mass transfer coefficient of adsorption column determined by Adams-Bohart equation was 1.61 x 10 -4 l x mg -1 x min -1 . The adsorption column can be easily regenerated by 0.1 mol x l -1 HNO 3 solution, showing outstanding ability of concentrating Th(IV). (author)

75 FR 81250 - Pulse Jet Mixing at the Waste Treatment and Immobilization Plant

Science.gov (United States)

2010-12-27

... Immobilization Plant (WTP) in conjunction with the Hanford tank farm waste feed delivery system will operate... imperative requires that the pulse jet mixing and transfer systems relied upon in the WTP design perform reliably and effectively for decades of WTP operations, and that technical issues with the performance of...

DOE materials program supporting immobilization of radioactive wastes

International Nuclear Information System (INIS)

Oertel, G.K.; Scheib, W.S. Jr.

1979-01-01

A summary is presented of the DOE program for developing waste-form criteria, immobilization processes, and generation and evaluation of performance characterization data. Interrelationships are discussed among repository design, materials requirements, immobilization process definition, quality assurance, and risk analysis as part of the National Environmental Policy Act and regulatory processes

Preparation and activity of bubbling-immobilized cellobiase within chitosan-alginate composite.

Science.gov (United States)

Wang, Fang; Su, Rong-Xin; Qi, Wei; Zhang, Ming-Jia; He, Zhi-Min

2010-01-01

Cellobiase can hydrolyze cellobiose into glucose; it plays a key role in the process of cellulose hydrolysis by reducing the product inhibition. To reuse the enzyme and improve the economic value of cellulosic ethanol, cellobiase was immobilized using sodium alginate and chitosan as carriers by the bubbling method. The immobilization conditions were optimized as follows: enzyme loading of 100 U cellobiase/g carrier, 30 min immobilization, 3.5 wt% sodium alginate, 0.25 wt% chitosan, and 2 wt% calcium chloride. Compared to free enzyme, the immobilized cellobiase had a decreased apparent K(m) and the maximum activity at a lower pH, indicating its higher acidic and thermal stability. The immobilized cellobiase was further tested in the hydrolysis of cellobiose and various cellulosic substrates (microcrystalline cellulose, filter paper, and ammonia-pretreated corn cobs). Together with cellulases, the immobilized cellobiase converted the cellulosic substrates into glucose with the rate and extent similar to the free enzyme.

Covalent immobilization of lipases on monodisperse magnetic microspheres modified with PAMAM-dendrimer

Energy Technology Data Exchange (ETDEWEB)

Zhu, Weiwei [Lanzhou University, State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Institute of Biochemical Engineering and Environmental Technology (China); Zhang, Yimei [Suzhou Research Academy of North China Electric Power University (China); Hou, Chen; Pan, Duo; He, Jianjun; Zhu, Hao, E-mail: zhuhao07@lzu.edu.cn [Lanzhou University, State Key Laboratory of Applied Organic Chemistry, Key Laboratory of Nonferrous Metal Chemistry and Resources Utilization of Gansu Province, College of Chemistry and Chemical Engineering, Institute of Biochemical Engineering and Environmental Technology (China)

2016-02-15

This paper reported an immobilization of Candida rugosa lipase (CRL) onto PAMAM-dendrimer-grafted magnetic nanoparticles synthesized by a modified solvothermal reduction method. The dendritic magnetic nanoparticles were amply characterized by several instrumental measurements, and the CRL was covalently anchored on the three generation supports with glutaraldehyde as coupling reagent. The amount of immobilized enzyme was up to 150 mg/g support and the factors related with the enzyme activity were investigated. The immobilization of lipase improved their performance in wider ranges of pH and temperature. The immobilized lipase exhibited excellent thermal stability and reusability in comparison with free enzyme and can be reused 10 cycles with the enzymatic activity remained above 90 %. The properties of lipase improved obviously after being immobilized on the dendritic supports. The inactive immobilized lipase could be regenerated with glutaraldehyde and Cu{sup 2+}, respectively. This synthetic strategy was facile and eco-friendly for applications in lipase immobilization.

Enhanced starch hydrolysis using α-amylase immobilized on cellulose ultrafiltration affinity membrane.

Science.gov (United States)

Konovalova, Viktoriia; Guzikevich, Kateryna; Burban, Anatoliy; Kujawski, Wojciech; Jarzynka, Karolina; Kujawa, Joanna

2016-11-05

In order to prepare ultrafiltration membranes possessing biocatalytic properties, α-amylase has been immobilized on cellulose membranes. Enzyme immobilization was based on a covalent bonding between chitosan and a surface of cellulose membrane, followed by an attachment of Cibacron Blue F3G-A dye as affinity ligand. Various factors affecting the immobilization process, such as enzyme concentration, pH of modifying solution, zeta-potential of membrane surface, and stability of immobilized enzyme were studied. The applicability of immobilized α-amylase has been investigated in ultrafiltration processes. The immobilization of α-amylase on membrane surface allows to increase the value of mass transfer coefficient and to decrease the concentration polarization effect during ultrafiltration of starch solutions. The enzyme layer on the membrane surface prevents a rapid increase of starch concentration due to the amylase hydrolysis of starch in the boundary layer. The presented affinity immobilization technique allows also for the regeneration of membranes from inactivated enzyme. Copyright © 2016 Elsevier Ltd. All rights reserved.

Pulsed electromagnetic field during cast immobilization in postmenopausal women with Colles’ fracture

Directory of Open Access Journals (Sweden)

Lazović Milica

2012-01-01

Full Text Available Introduction. Although Colles’ fracture i.e. a dorsally displaced distal radius fracture (DRF is one of the most common fractures, there is no enough evidence to determine the best form of rehabilitation. Objective. To assess whether the use of pulsed electromagnetic field (PEMF therapy during cast immobilization of DRF provides beneficial effects on pain, edema, wrist range of motion and function, as well as on the frequency of complications immediately after cast removal. Methods. The prospective randomized controlled study included 60 women over the age of 55 years with extra-articular displaced DRF treated with reduction and cast immobilization. The patients were alternately allocated to either a PEMF group (n=30, received 10 days of PEMF therapy during immobilization, or a control group (n=30, without PEMF therapy. Pain, function, hand circumference, wrist and forearm range of motion and frequency of complications for each patient was evaluated within two to three days of cast removal. Results. Better mean values for the majority of examined parameters were recorded in the PEMF group than in the control group, but the difference was statistically significant just for edema (p<0.001, flexion, extension and supination range (p<0.01. Conclusion. During immobilization PEMF therapy in DRF patients gave better results immediately after cast removal in terms of edema and wrist range of motion (ROM.

Report on a randomized trial comparing two forms of immobilization of the head for fractionated stereotactic radiotherapy

International Nuclear Information System (INIS)

Bednarz, Greg; Machtay, Mitchell; Werner-Wasik, Maria; Downes, Beverly; Bogner, Joachim; Hyslop, Terry; Galvin, James; Evans, James; Curran, Walter Jr.; Andrews, David

2009-01-01

Fractionated stereotactic radiotherapy (SRT) requires accurate and reproducible immobilization of the patient's head. This randomized study compared the efficacy of two commonly used forms of immobilization used for SRT. Two routinely used methods of immobilization, which differ in their approach to reproduce the head position from day to day, are the Gill-Thomas-Cosman (GTC) frame and the BrainLab thermoplastic mask. The GTC frame fixates on the patient's upper dentition and thus is in direct mechanical contact with the cranium. The BrainLab mask is a two-part masking system custom fitted to the front and back of the patient's head. After patients signed an IRB-approved informed consent form, eligible patients were randomized to either GTC frame or mask for their course of SRT. Patients were treated as per standard procedure; however, prior to each treatment a set of digital kilovolt images (ExacTrac, BrainLabAB, Germany) was taken. These images were fused with reference digitally reconstructed radiographs obtained from treatment planning CT to yield lateral, longitudinal, and vertical deviations of isocenter and head rotations about respective axes. The primary end point of the study was to compare the two systems with respect to mean and standard deviations using the distance to isocenter measure. A total of 84 patients were enrolled (69 patients evaluable with detailed positioning data). A mixed-effect linear regression and two-tiled t test were used to compare the distance measure for both the systems. There was a statistically significant (p<0.001) difference between mean distances for these systems, suggesting that the GTC frame was more accurate. The mean 3D displacement and standard deviations were 3.17+1.95 mm for mask and 2.00+1.04 mm for frame. Both immobilization techniques were highly effective, but the GTC frame was more accurate. To optimize the accuracy of SRT, daily kilovolt image guidance is recommended with either immobilization system.

Integrated development and testing plan for the plutonium immobilization project

International Nuclear Information System (INIS)

Kan, T.

1998-01-01

This integrated plan for the DOE Office of Fissile Materials Disposition (MD) describes the technology development and major project activities necessary to support the deployment of the immobilization approach for disposition of surplus weapons-usable plutonium. The plan describes details of the development and testing (D and T) tasks needed to provide technical data for design and operation of a plutonium immobilization plant based on the ceramic can-in-canister technology (''Immobilization Fissile Material Disposition Program Final Immobilization Form Assessment and Recommendation'', UCRL-ID-128705, October 3, 1997). The plan also presents tasks for characterization and performance testing of the immobilization form to support a repository licensing application and to develop the basis for repository acceptance of the plutonium form. Essential elements of the plant project (design, construction, facility activation, etc.) are described, but not developed in detail, to indicate how the D and T results tie into the overall plant project. Given the importance of repository acceptance, specific activities to be conducted by the Office of Civilian Radioactive Waste Management (RW) to incorporate the plutonium form in the repository licensing application are provided in this document, together with a summary of how immobilization D and T activities provide input to the license activity. The ultimate goal of the Immobilization Project is to develop, construct, and operate facilities that will immobilize from about 18 to 50 tonnes (MT) of U.S. surplus weapons usable plutonium materials in a manner that meets the ''spent fuel'' standard (Fissile Materials Storage and Disposition Programmatic Environmental Impact Statement Record of Decision, ''Storage and Disposition Final PEIS'', issued January 14, 1997, 62 Federal Register 3014) and is acceptable for disposal in a geologic repository. In the can-in-canister technology, this is accomplished by encapsulating the

Light transfer in agar immobilized microalgae cell cultures

Science.gov (United States)

Kandilian, Razmig; Jesus, Bruno; Legrand, Jack; Pilon, Laurent; Pruvost, Jérémy

2017-09-01

This paper experimentally and theoretically investigates light transfer in agar-immobilized cell cultures. Certain biotechnological applications such as production of metabolites secreted by photosynthetic microorganisms require cells to be immobilized in biopolymers to minimize contamination and to facilitate metabolite recovery. In such applications, light absorption by cells is one of the most important parameters affecting cell growth or metabolite productivity. Modeling light transfer therein can aid design and optimize immobilized-cell reactors. In this study, Parachlorella kessleri cells with areal biomass concentrations ranging from 0.36 to 16.9 g/m2 were immobilized in 2.6 mm thick agar gels. The average absorption and scattering cross-sections as well as the scattering phase function of P. kessleri cells were measured. Then, the absorption and transport scattering coefficients of the agar gel were determined using an inverse method based on the modified two-flux approximation. The forward model was used to predict the normal-hemispherical transmittance and reflectance of the immobilized-cell films accounting for absorption and scattering by both microalgae and the agar gel. Good agreement was found between the measured and predicted normal-hemispherical transmittance and reflectance provided absorption and scattering by agar were taken into account. Moreover, good agreement was found between experimentally measured and predicted mean rate of photon absorption. Finally, optimal areal biomass concentration was determined to achieve complete absorption of the incident radiation.

Electrochemistry of immobilized particles and droplets experiments with three-phase electrodes

CERN Document Server

Scholz, Fritz; Gulaboski, Rubin; Schröder, Uwe

2014-01-01

This second edition of a successful and highly-accessed monograph has been extended by more than 100 pages. It includes an enlarged coverage of applications for materials characterization and analysis. Also a more detailed description of strategies for determining free energies of ion transfer between miscible liquids is provided. This is now possible with a "third-phase strategy" which the authors explain from theoretical and practical points of view. The book is still the only one detailing strategies for solid state electroanalysis. It also features the specific potential of the techniques to use immobilized particles (for studies of solid materials) and of immobilized droplets of immiscible liquids for the purpose of studying the three-phase electrochemistry of these liquids. This also includes studies of ion transfer between aqueous and immiscible non-aqueous liquids. The bibliography of all published papers in this field of research has been expanded from 318 to now 444 references in this second editi...

Determination of conformation and orientation of immobilized peptides and proteins at buried interfaces

Science.gov (United States)

Shen, Lei; Ulrich, Nathan W.; Mello, Charlene M.; Chen, Zhan

2015-01-01

Surface immobilized peptides/proteins have important applications such as antimicrobial coating and biosensing. We report a study of such peptides/proteins using sum frequency generation vibrational spectroscopy and ATR-FTIR. Immobilization on surfaces via physical adsorption and chemical coupling revealed that structures of chemically immobilized peptides are determined by immobilization sites, chemical environments, and substrate surfaces. In addition, controlling enzyme orientation by engineering the surface immobilization site demonstrated that structures can be well-correlated to measured chemical activity. This research facilitates the development of immobilized peptides/proteins with improved activities by optimizing their surface orientation and structure.

Reversal of haloperidol induced motor deficits in rats exposed to repeated immobilization stress.

Science.gov (United States)

Shireen, Erum; Pervez, Sidra; Masroor, Maria; Ali, Wafa Binte; Rais, Qudsia; Khalil, Samira; Tariq, Anum; Haleem, Darakshan Jabeen

2014-09-01

Stress is defined as a non specific response of body to any physiological and psychological demand. Preclinical studies have shown that an uncontrollable stress condition produces neurochemical and behavioral deficits. The present study was conducted to test the hypothesis that a decrease in the responsiveness of somatodendritic 5-hydroxytryptamine (5-HT)-1A receptors following adaptation to stress could attenuate haloperidol induced acute parkinsonian like effect. Results showed that single exposure (2h) to immobilization stress markedly decreased food intake, growth rate and locomotor activity but these stress-induced behavioral deficits were not observed following repeated (2h/day for 5 days) exposure of immobilization stress suggesting behavioral tolerance occurs to similar stress. An important finding of present study is a reversal of haloperidol-induced motor deficits in animals exposed to repeated immobilization stress than respective control animals. It is suggested that stress induced possible desensitization of somatodendritic 5-HT-1A as well as 5-HT-2C receptors could release dopamine system from the inhibitory influence of serotonin. On the other hand, an increase in the effectiveness of postsynaptic 5-HT-1A receptors elicits a direct stimulatory influence on the activity of dopaminergic neuron and is possibly involved in the reversal of haloperidol-induced parkinsonian like symptoms in repeatedly immobilized rats.

Immobilization of catalase on chitosan and amino acid- modified chitosan beads.

Science.gov (United States)

Başak, Esra; Aydemir, Tülin

2013-08-01

Bovine liver catalase was covalently immobilized onto amino acid-modified chitosan beads. The beads were characterized with SEM, FTIR, TGA and the effects of immobilization on optimum pH and temperature, thermostability, reusability were evaluated. Immobilized catalase showed the maximal enzyme activity at pH 7.0 at 30°C. The kinetic parameters, Km and Vmax, for immobilized catalase on alanine-chitosan beads and lysine-chitosan beads were estimated to be 25.67 mM, 27 mM and 201.39 μmol H2O2/min, 197.50 μmol H2O2/min, respectively. The activity of the immobilized catalase on Ala-CB and Lys-CB retained 40% of its high initial activity after 100 times of reuse.

Immobilization of Candida antarctica Lipase B by Covalent Attachment to Green Coconut Fiber

Science.gov (United States)

Brígida, Ana I. S.; Pinheiro, Álvaro D. T.; Ferreira, Andrea L. O.; Pinto, Gustavo A. S.; Gonçalves, Luciana R. B.

The objective of this study was to covalently immobilize Candida antarctica type B lipase (CALB) onto silanized green coconut fibers. Variables known to control the number of bonds between enzyme and support were evaluated including contact time, pH, and final reduction with sodium borohydride. Optimal conditions for lipase immobilization were found to be 2h incubation at both pH 7.0 and 10.0. Thermal stability studies at 60°C showed that the immobilized lipase prepared at pH 10.0 (CALB-10) was 363-fold more stable than the soluble enzyme and 5.4-fold more stable than the biocatalyst prepared at pH 7.0 (CALB-7). CALB-7 was found to have higher specific activity and better stability when stored at 5°C. When sodium borohydride was used as reducing agent on CALB-10 there were no improvement in storage stability and at 60°C stability was reduced for both CALB-7 and CALB-10.

Covalent immobilization of invertase on PAMAM-dendrimer modified superparamagnetic iron oxide nanoparticles

International Nuclear Information System (INIS)

Uzun, K.; Cevik, E.; Senel, M.; Soezeri, H.; Baykal, A.; Abasiyanik, M. F.; Toprak, M. S.

2010-01-01

In this study, polyamidoamine (PAMAM) dendrimer was synthesized on the surface of superparamagnetite nanoparticles to enhance invertase immobilization. The amount of immobilized enzyme on the surface-hyperbranched magnetite nanoparticle was up to 2.5 times (i.e., 250%) as much as that of magnetite nanoparticle modified with only amino silane. Maximum reaction rate (V max ) and Michaelis-Menten constant (K m ) were determined for the free and immobilized enzymes. Various characteristics of immobilized invertase such as; the temperature activity, thermal stability, operational stability, and storage stability were evaluated and results revealed that stability of the enzyme is improved upon immobilization.

The effects of below-elbow immobilization on driving performance.

Science.gov (United States)

Jones, Evan M; Barrow, Aaron E; Skordas, Nic J; Green, David P; Cho, Mickey S

2017-02-01

There is limited research to guide physicians and patients in deciding whether it is safe to drive while wearing various forms of upper extremity immobilization. The purpose of this study is to evaluate the effect of below-elbow removable splints and fiberglass casts on automobile driving performance. 20 healthy subjects completed 10 runs through a closed, cone-marked driving course while wearing a randomized sequence of four different types of immobilization on each extremity (short arm thumb spica fiberglass cast, short arm fiberglass cast, short arm thumb spica splint, and short arm wrist splint). The first and last driving runs were without immobilization and served as controls. Performance was measured based on evaluation by a certified driving instructor (pass/fail scoring), cones hit, run time, and subject-perceived driving difficulty (1-10 analogue scoring). The greatest number of instructor-scored failures occurred while immobilized in right arm spica casts (n=6; p=0.02) and left arm spica casts (n=5; p=0.049). The right arm spica cast had the highest subject-perceived difficulty (5.2±1.9; pimmobilization had significantly increased perceived difficulty compared to control, except for the left short arm splint (2.5±1.6; p>0.05). There was no significant difference in number of cones hit or driving time between control runs and runs with any type of immobilization. Drivers should use caution when wearing any of the forms of upper extremity immobilization tested in this study. All forms of immobilization, with exception of the left short arm splint significantly increased perceived driving difficulty. However, only the fiberglass spica casts (both left and right arm), significantly increased drive run failures due to loss of vehicle control. We recommend against driving when wearing a below-elbow fiberglass spica cast on either extremity. Copyright © 2016. Published by Elsevier Ltd.

Enhanced activity and stability of L-arabinose isomerase by immobilization on aminopropyl glass.

Science.gov (United States)

Zhang, Ye-Wang; Jeya, Marimuthu; Lee, Jung-Kul

2011-03-01

Immobilization of Bacillus licheniformis L: -arabinose isomerase (BLAI) on aminopropyl glass modified with glutaraldehyde (4 mg protein g support⁻¹) was found to enhance the enzyme activity. The immobilization yield of BLAI was proportional to the quantity of amino groups on the surface of support. Reducing particle size increased the adsorption capacity (q(m)) and affinity (k(a)). The pH and temperature for immobilization were optimized to be pH 7.1 and 33 °C using response surface methodology (RSM). The immobilized enzyme was characterized and compared to the free enzyme. There is no change in optimal pH and temperature before and after immobilization. However, the immobilized BLAI enzyme achieved 145% of the activity of the free enzyme. Correspondingly, the catalytic efficiency (k(cat)/K(m)) was improved 1.47-fold after immobilization compared to the free enzyme. The thermal stability was improved 138-fold (t₁/₂) increased from 2 to 275 h) at 50 °C following immobilization.

Uranium speciation and stability after reductive immobilization in aquifer sediments

Science.gov (United States)

Sharp, Jonathan O.; Lezama-Pacheco, Juan S.; Schofield, Eleanor J.; Junier, Pilar; Ulrich, Kai-Uwe; Chinni, Satya; Veeramani, Harish; Margot-Roquier, Camille; Webb, Samuel M.; Tebo, Bradley M.; Giammar, Daniel E.; Bargar, John R.; Bernier-Latmani, Rizlan

2011-11-01

It has generally been assumed that the bioreduction of hexavalent uranium in groundwater systems will result in the precipitation of immobile uraninite (UO 2). In order to explore the form and stability of uranium immobilized under these conditions, we introduced lactate (15 mM for 3 months) into flow-through columns containing sediments derived from a former uranium-processing site at Old Rifle, CO. This resulted in metal-reducing conditions as evidenced by concurrent uranium uptake and iron release. Despite initial augmentation with Shewanella oneidensis, bacteria belonging to the phylum Firmicutes dominated the biostimulated columns. The immobilization of uranium (˜1 mmol U per kg sediment) enabled analysis by X-ray absorption spectroscopy (XAS). Tetravalent uranium associated with these sediments did not have spectroscopic signatures representative of U-U shells or crystalline UO 2. Analysis by microfocused XAS revealed concentrated micrometer regions of solid U(IV) that had spectroscopic signatures consistent with bulk analyses and a poor proximal correlation (μm scale resolution) between U and Fe. A plausible explanation, supported by biogeochemical conditions and spectral interpretations, is uranium association with phosphoryl moieties found in biomass; hence implicating direct enzymatic uranium reduction. After the immobilization phase, two months of in situ exposure to oxic influent did not result in substantial uranium remobilization. Ex situ flow-through experiments demonstrated more rapid uranium mobilization than observed in column oxidation studies and indicated that sediment-associated U(IV) is more mobile than biogenic UO 2. This work suggests that in situ uranium bioimmobilization studies and subsurface modeling parameters should be expanded to account for non-uraninite U(IV) species associated with biomass.

Busuioceanu, S.: Corporal immobilization reassessment accountancy and tax alternatives

Directory of Open Access Journals (Sweden)

Busuioceanu, S.

2012-01-01

Full Text Available The economic phenomena and process like the market evolution, the inflation and globalization have also triggered in accountancy the evolution from historical cost system to current cost. The corporal immobilization reassessment at the level of current cost must represent the real motivation to contribute to a truthful image of the patrimony and not a method of depreciating tax costs of economic operators.

Bioremediation of contaminated surface water by immobilized Micrococcus roseus.

Science.gov (United States)

Li, H; Li, P; Hua, T; Zhang, Y; Xiong, X; Gong, Z

2005-08-01

The problems caused by contaminated surface water have gradually become more serious in recent years. Although various remediation technologies were investigated, unfortunately, no efficient method was developed. In this paper, a new bioremediation technology was studied using Micrococcus roseus, which was immobilized in porous spherical beads by an improved polyvinyl alcohol (PVA) - sodium alginate (SA) embedding method. The experimental results indicated that COD removal rate could reach 64.7 % within 72 hours when immobilized M. roseus beads were used, which was ten times as high as that of free cells. The optimum inoculation rate of immobilized M. roseus beads was 10 % (mass percent of the beads in water sample, g g(-1)). Suitable aeration was proved necessary to enhance the bioremediation process. The immobilized cells had an excellent tolerance to pH and temperature changes, and were also more resistant to heavy metal stress compared with free cells. The immobilized M. roseus beads had an excellent regeneration capacity and could be reused after 180-day continuous usage. The Scanning Electronic Microscope (SEM) analysis showed that the bead microstructure was suitable for M. roseus growth, however, some defect structures should still be improved.

Immobilization as a route to surplus fissile materials disposition

International Nuclear Information System (INIS)

Gray, L.W.; Kan, T.

1995-01-01

In the aftermath of the Cold War, the US and Russia have agreed to large reductions in nuclear weapons. To aid in the selection of long-term management options, DOE has undertaken a multifaceted study to select options for storage and disposition of plutonium (Pu) in keeping with the national policy that Pu must be subjected to the highest standards of safety, security, and accountability. One alternative being considered is immobilization. To arrive at a suitable immobilization form, the authors first reviewed published information on high-level waste (HLW) immobilization technologies in order to identify 72 possible Pu immobilization forms to be prescreened. Surviving forms were screened using multiattribute analysis to determine the most promising technologies. Promising immobilization families were further evaluated to identify chemical, engineering, environmental, safety, and health problems that remain to be solved prior to making technical decisions as to the viability of using the form for long-term disposition of plutonium. All data, analyses, and reports are being provided to the DOE Fissile Materials Disposition Project Office to support the Record of Decision that is anticipated in the fourth quarter of FY96

A MoS₂-based system for efficient immobilization of hemoglobin and biosensing applications.

Science.gov (United States)

Chao, Jie; Zou, Min; Zhang, Chi; Sun, Haofan; Pan, Dun; Pei, Hao; Su, Shao; Yuwen, Lihui; Fan, Chunhai; Wang, Lianhui

2015-07-10

A novel hydrogen peroxide (H2O2) and nitric oxide (NO) biosensor was fabricated by immobilizing hemoglobin (Hb) on a gold nanoparticle-decorated MoS2 nanosheet (AuNPs@MoS2) nanocomposite film modified glass carbon electrode. The AuNPs@MoS2 nanocomposite not only made the immobilized Hb keep its native biological activity but also facilitated the electron transfer between electrode and the electroactive center of Hb due to its excellent conductivity and biocompatibility. The direct electrochemistry and bioelectrocatalytic activity of Hb were investigated by cyclic voltammetry (CV). The modified electrode showed good electrocatalytic ability toward the reduction of H2O2 and NO. Under optimal conditions, the current response was linear with the concentration of H2O2 and NO in the range from 10 to 300 μM and 10 to 1100 μM with a detection limit of 4 and 5 μM, respectively. This MoS2-based biosensor was sensitive, reproducible and stable, indicating that AuNPs@MoS2 nanocomposite maybe a promising platform to construct electrochemical sensors for chemical and biological molecules detection.

Immobilization of iodine in concrete

Science.gov (United States)

Clark, Walter E.; Thompson, Clarence T.

1977-04-12

A method for immobilizing fission product radioactive iodine recovered from irradiated nuclear fuel comprises combining material comprising water, Portland cement and about 3-20 wt. % iodine as Ba(IO.sub.3).sub.2 to provide a fluid mixture and allowing the fluid mixture to harden, said Ba(IO.sub.3).sub.2 comprising said radioactive iodine. An article for solid waste disposal comprises concrete prepared by this method. BACKGROUND OF THE INVENTION This invention was made in the course of, or under a contract with the Energy Research and Development Administration. It relates in general to reactor waste solidification and more specifically to the immobilization of fission product radioactive iodine recovered from irradiated nuclear fuel for underground storage.

Improvement of thermal-stability of enzyme immobilized onto mesoporous zirconia

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Yuichi Masuda

2014-03-01

Thereafter, FDH immobilized on MPZ showed higher catalytic activity than that on MPS. Enhancement of catalytic activity was obtained by improving the substrate affinity derived from interparticle voids of MPZ. In addition, the FDH immobilized on MPZ had a very great higher thermal stability. Further investigation using transmittance Infrared spectroscopy indicated that the high-order structure of the FDH immobilized on MPZ did not get altered after the heat-treatment.

Immobilization of enzyme and antibody by low energy electron beam polymerization

International Nuclear Information System (INIS)

Kaetsu, Isao; Kumakura, Minoru

1987-01-01

Immobilization of glucoamylase and AFP-antibody was studied using an electron beam of relatively low energy. A thin polymer membrane formed by irradiation of monomer enzyme mixture in a buffer, which had a considerable enzymatic activity. A membrane of almost the same thickness and activity was obtained by repeated irradiation. The effect of irradiation conditions on the immobilization and the variations of irradiation method for immobilization were investigated. The immobilization of antibody was carried out in similar ways as for enzyme, and the product also showed a considerable activity. (author)

Surface functionalization of superparamagnetic nanoparticles encapsulated by chitosan for protein immobilization; Funcionalizacao da superficie de nanoparticulas superparamagneticas encapsuladas por quitosana para a imobilizacao de proteinas

Energy Technology Data Exchange (ETDEWEB)

Sousa, Jose Silva de

2010-07-01

Nanoscience and nanotechnology have opened up numerous developments of devices and systems on the nanometer scale, with new molecular organization, properties and functions. In this context, the polymeric magnetic nanoparticles are composites formed by magnetic materials with a particle size between 1 and 100 nm combined with functional polymers. They are well-known and have been widely studied because of its applications in various technology areas. Applications on the biological and medical areas include separation and immobilization of enzymes and proteins, improved techniques of magnetic resonance imaging and diagnostic systems for controlled drug delivery. In this work, proteins were immobilized on the surface of a biopolymer combined with superparamagnetic particles of magnetite. The biopolymer chitosan was used, cross-linked and functionalized with glutaraldehyde, applicable to the biological assays. Three types of magnetic composites were obtained, which were called QM1Glu, QM2NaGlu and QM3Glu. They were characterized by X-ray diffraction, scanning electron microscopy, vibrating sample magnetometry, differential scanning calorimetry, thermogravimetry and infrared spectroscopy. They were evaluated concerning the immobilization of the proteins bovine serum albumin (BSA), collagen and trypsin. The study showed that the immobilization of proteins on the biopolymer occurred in 30 min of incubation. The magnetic composite of non functionalized chitosan (QM3) was also evaluated. For trypsin, it was found that the immobilization potential of QM3 was higher than that observed for QM3Glu. After 30 days, the trypsin of the QM3-Trip and QM3Glu-Trip was still with activity. The activity and the enzyme kinetics of the QM3Glu-Trip with the substrate BApNA were demonstrated. (author)

Cost-effective immobilization for whole brain radiation therapy.

Science.gov (United States)

Rubinstein, Ashley E; Ingram, W Scott; Anderson, Brian M; Gay, Skylar S; Fave, Xenia J; Ger, Rachel B; McCarroll, Rachel E; Owens, Constance A; Netherton, Tucker J; Kisling, Kelly D; Court, Laurence E; Yang, Jinzhong; Li, Yuting; Lee, Joonsang; Mackin, Dennis S; Cardenas, Carlos E

2017-07-01

To investigate the inter- and intra-fraction motion associated with the use of a low-cost tape immobilization technique as an alternative to thermoplastic immobilization masks for whole-brain treatments. The results of this study may be of interest to clinical staff with severely limited resources (e.g., in low-income countries) and also when treating patients who cannot tolerate standard immobilization masks. Setup reproducibility of eight healthy volunteers was assessed for two different immobilization techniques. (a) One strip of tape was placed across the volunteer's forehead and attached to the sides of the treatment table. (b) A second strip was added to the first, under the chin, and secured to the table above the volunteer's head. After initial positioning, anterior and lateral photographs were acquired. Volunteers were positioned five times with each technique to allow calculation of inter-fraction reproducibility measurements. To estimate intra-fraction reproducibility, 5-minute anterior and lateral videos were taken for each technique per volunteer. An in-house software was used to analyze the photos and videos to assess setup reproducibility. The maximum intra-fraction displacement for all volunteers was 2.8 mm. Intra-fraction motion increased with time on table. The maximum inter-fraction range of positions for all volunteers was 5.4 mm. The magnitude of inter-fraction and intra-fraction motion found using the "1-strip" and "2-strip" tape immobilization techniques was comparable to motion restrictions provided by a thermoplastic mask for whole-brain radiotherapy. The results suggest that tape-based immobilization techniques represent an economical and useful alternative to the thermoplastic mask. © 2017 The Authors. Journal of Applied Clinical Medical Physics published by Wiley Periodicals, Inc. on behalf of American Association of Physicists in Medicine.

PVA-Glutaraldehyde as support for lectin immobilization and affinity chromatography

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Moacyr Jesus Barreto de Melo Rêgo

2016-12-01

Full Text Available Immobilized lectins are a powerful biotechnological tool for separation and isolation of glycoconjugates. In the present study, polyvinyl alcohol (PVA and glutaraldehyde (GA were used as a support for Concanavalin A (Con A covalent immobilization and for entrapment of Parkia pendula seed gum (PpeG. Con A immobilization yielded approximately 30% and 0.6 M glucose solution was the minimum concentration able to elute fetuin from column. PVA-GA-PpeG column was efficiently recognized by pure P. pendula lectin (PpeL. These findings indicate that PVA-GA interpenetrated network showed to be an efficient support for lectin covalent immobilization and as affinity chromatography matrix after trapping of PpeG.

Performance Criteria for Capture and/or Immobilization Technologies - Milestone Report

Energy Technology Data Exchange (ETDEWEB)

Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Spencer, Barry B. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Soelberg, Nick [Idaho National Lab. (INL), Idaho Falls, ID (United States); Riley, Brian [Pacific Northwest National Lab. (PNNL), Richland, WA (United States)

2016-02-01

The capture and subsequent immobilization of the four regulated volatile radionuclides (³H, ¹⁴C, ⁸⁵Kr, and ¹²⁹I) from the off-gas streams of a used nuclear fuel (UNF) reprocessing facility has been a topic of substantial research interest for the US Department of Energy and its international colleagues. Removal of some or all of these radionuclides (e.g., based upon fuel burnup, fuel type, cooling time) from the plant effluent streams prior to discharge to the environment is required to meet regulations set forth by the US Environmental Protection Agency. Upon removal, the radionuclide, as well as associated sorbents that cannot be cost-effectively regenerated, is destined for conversion to a waste form. Research in separation and capture methodologies has included a wide range of technologies, including liquid caustic scrubbing systems, solid adsorbents, and cryogenic distillation. The studies of waste forms have been correspondingly diverse. In considering the technologies available for future development and implementation of both sorbents and waste forms, it is necessary to identify benchmark measures of performance to evaluate objectively each sorbent system or waste form.

Materials Science of High-Level Nuclear Waste Immobilization

International Nuclear Information System (INIS)

Weber, William J.; Navrotsky, Alexandra; Stefanovsky, S. V.; Vance, E. R.; Vernaz, Etienne Y.

2009-01-01

With the increasing demand for the development of more nuclear power comes the responsibility to address the technical challenges of immobilizing high-level nuclear wastes in stable solid forms for interim storage or disposition in geologic repositories. The immobilization of high-level nuclear wastes has been an active area of research and development for over 50 years. Borosilicate glasses and complex ceramic composites have been developed to meet many technical challenges and current needs, although regulatory issues, which vary widely from country to country, have yet to be resolved. Cooperative international programs to develop advanced proliferation-resistant nuclear technologies to close the nuclear fuel cycle and increase the efficiency of nuclear energy production might create new separation waste streams that could demand new concepts and materials for nuclear waste immobilization. This article reviews the current state-of-the-art understanding regarding the materials science of glasses and ceramics for the immobilization of high-level nuclear waste and excess nuclear materials and discusses approaches to address new waste streams

Synthesis of glycinamides using protease immobilized magnetic nanoparticles

Directory of Open Access Journals (Sweden)

Abha Sahu

2016-12-01

Full Text Available In the present investigation, Bacillus subtilis was isolated from slaughterhouse waste and screened for the production of protease enzyme. The purified protease was successfully immobilized on magnetic nanoparticles (MNPs and used for the synthesis of series of glycinamides. The binding and thermal stability of protease on MNPs was confirmed by FTIR spectroscopy and TGA analysis. The surface morphology of MNPs before and after protease immobilization was carried out using SEM analysis. XRD pattern revealed no phase change in MNPs after enzyme immobilization. The processing parameters for glycinamides synthesis viz. temperature, pH, and time were optimized using Response Surface Methodology (RSM by using Design Expert (9.0.6.2. The maximum yield of various amides 2 butyramidoacetic acid (AMD-1,83.4%, 2-benzamidoacetic acid (AMD-2,80.5% and 2,2′((carboxymethyl amino-2-oxoethyl-2-hydroxysuccinylbis(azanediyldiacetic acid (AMD-3,80.8% formed was observed at pH-8, 50 °C and 30 min. The synthesized immobilized protease retained 70% of the initial activity even after 8 cycles of reuse.

A non-invasive immobilization system and related quality assurance for dynamic intensity modulated radiation therapy of intracranial and head and neck disease

International Nuclear Information System (INIS)

Tsai Jensan; Engler, Mark J.; Ling, Marilyn N.; Wu, Julian K.; Kramer, Bradley; Dipetrillo, Thomas; Wazer, David E.

1999-01-01

Purpose: To develop and implement a non-invasive immobilization system guided by a dedicated quality assurance (QA) program for dynamic intensity-modulated radiotherapy (IMRT) of intracranial and head and neck disease, with IMRT delivered using the NOMOS Corporation's Peacock System and MIMiC collimator. Methods and Materials: Thermoplastic face masks are combined with cradle-shaped polyurethane foaming agents and a dedicated quality assurance program to create a customized headholder system (CHS). Plastic shrinkage was studied to understand its effect on immobilization. Fiducial points for computerized tomography (CT) are obtained by placing multiple dabs of barium paste on mask surfaces at intersections of laser projections used for patient positioning. Fiducial lines are drawn on the cradle along laser projections aligned with nasal surfaces. Lateral CT topograms are annotated with a crosshair indicating the origin of the treatment planning and delivery coordinate system, and with lines delineating the projections of superior-inferior field borders of the linear accelerator's secondary collimators, or with those of the fully open MIMiC. Port films exposed with and without the MIMiC are compared to annotated topograms to measure positional variance (PV) in superior-inferior (SI), right-left (RL), and anterior posterior (AP) directions. MIMiC vane patterns superposed on port films are applied to verify planned patterns. A 12-patient study of PV was performed by analyzing positions of 10 anatomic points on repeat CT topograms, plotting histograms of PV, and determining average PV. Results and Discussion: A 1.5 ± 0.3 mm SD shrinkage per 70 cm of thermoplastic was observed over 24 h. Average PV of 1.0 ± 0.8, 1.2 ± 1.1, and 1.3 ± 0.8 mm were measured in SI, AP, and RL directions, respectively. Lateral port films exposed with and without the MIMiC showed PV of 0.2 ± 1.3 and 0.8 ± 2.2 mm in AP and SI directions. Vane patterns superimposed on port films

Enzyme-Catalyzed Oxidation of 17β-Estradiol Using Immobilized Laccase from Trametes versicolor

Science.gov (United States)

Cardinal-Watkins, Chantale; Nicell, Jim A.