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Sample records for sample preparation procedure

  1. Comparison of sample preparation procedures on metal(loid) fractionation patterns in lichens.

    Science.gov (United States)

    Kroukamp, E M; Godeto, T W; Forbes, P B C

    2017-08-13

    The effects of different sample preparation strategies and storage on metal(loid) fractionation trends in plant material is largely underresearched. In this study, a bulk sample of lichen Parmotrema austrosinense (Zahlbr.) Hale was analysed for its total extractable metal(loid) content by ICP-MS, and was determined to be adequately homogenous (sample were prepared utilising a range of sample preservation techniques and subjected to a modified sequential extraction procedure or to total metal extraction. Both experiments were repeated after 1-month storage at 4 °C. Cryogenic freezing gave the best reproducibility for total extractable elemental concentrations between months, indicating this to be the most suitable method of sample preparation in such studies. The combined extraction efficiencies were >82% for As, Cu, Mn, Pb, Sr and Zn but poor for other elements, where sample preparation strategies 'no sample preparation' and 'dried in a desiccator' had the best extraction recoveries. Cryogenic freezing procedures had a significantly (p sample cleaning and preservation when species fractionation patterns are of interest. This study also shows that the assumption that species stability can be ensured through cryopreservation and freeze drying techniques needs to be revisited.

  2. Sample preparation procedures utilized in microbial metabolomics: An overview.

    Science.gov (United States)

    Patejko, Małgorzata; Jacyna, Julia; Markuszewski, Michał J

    2017-02-01

    Bacteria are remarkably diverse in terms of their size, structure and biochemical properties. Due to this fact, it is hard to develop a universal method for handling bacteria cultures during metabolomic analysis. The choice of suitable processing methods constitutes a key element in any analysis, because only appropriate selection of procedures may provide accurate results, leading to reliable conclusions. Because of that, every analytical experiment concerning bacteria requires individually and very carefully planned research methodology. Although every study varies in terms of sample preparation, there are few general steps to follow while planning experiment, like sampling, separation of cells from growth medium, stopping their metabolism and extraction. As a result of extraction, all intracellular metabolites should be washed out from cell environment. What is more, extraction method utilized cannot cause any chemical decomposition or degradation of the metabolome. Furthermore, chosen extraction method should correlate with analytical technique, so it will not disturb or prolong following sample preparation steps. For those reasons, we observe a need to summarize sample preparation procedures currently utilized in microbial metabolomic studies. In the presented overview, papers concerning analysis of extra- and intracellular metabolites, published over the last decade, have been discussed. Presented work gives some basic guidelines that might be useful while planning experiments in microbial metabolomics. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Sampling, storage and sample preparation procedures for X ray fluorescence analysis of environmental materials

    International Nuclear Information System (INIS)

    1997-06-01

    X ray fluorescence (XRF) method is one of the most commonly used nuclear analytical technique because of its multielement and non-destructive character, speed, economy and ease of operation. From the point of view of quality assurance practices, sampling and sample preparation procedures are the most crucial steps in all analytical techniques, (including X ray fluorescence) applied for the analysis of heterogeneous materials. This technical document covers recent modes of the X ray fluorescence method and recent developments in sample preparation techniques for the analysis of environmental materials. Refs, figs, tabs

  4. 9 CFR 147.8 - Procedures for preparing egg yolk samples for diagnostic tests.

    Science.gov (United States)

    2010-01-01

    ... samples for diagnostic tests. 147.8 Section 147.8 Animals and Animal Products ANIMAL AND PLANT HEALTH... IMPROVEMENT PLAN Blood Testing Procedures § 147.8 Procedures for preparing egg yolk samples for diagnostic... for diagnostic testing. (b) The authorized laboratory must identify each egg as to the breeding flock...

  5. Comparison of two sample preparation procedures for HPLC determination of ochratoxin A

    Directory of Open Access Journals (Sweden)

    Vuković Gorica L.

    2009-01-01

    Full Text Available In preparation of samples for chromatographic determination of ochratoxin A, two types of columns were used for sample cleanup (SPE and immunoaffinity columns. The first method consisted of liquid-liquid extraction with a mixture of chloroform and phosphoric acid, followed by ion-exchange cleanup on Waters Oasis MAX columns. The sec­ond method consisted of extraction with a mixture of water and methanol, followed by LCTech OtaCLEAN immunoaf­finity column cleanup. Recoveries of the methods were determined at three levels in three repetitions for maize flour, and they were 84% (%RSD = 19.2 for the first method of sample preparation and 101% (%RSD = 2.2 for the second method. Values of LOQ for OTA were 0.25 and 1.00 μg/kg for the IAC and SPE clean-up procedures, respectively. Both methods comply with present regulations, but the MAX sample clean-up procedure should be used as an alternative, since the immunoaffinity column clean-up procedure is characterized by better reproducibility, accuracy, and efficiency.

  6. Influence of rice sample preparation and milling procedures on milling quality appraisals

    Science.gov (United States)

    The objective of this research was to investigate the effect of sample preparation and milling procedure on milling quality appraisals of rough rice. Samples of freshly harvested medium-grain rice (M202) with different initial moisture contents (MCs) ranging from 20.2% to 25.1% (w.b.) were used for...

  7. Sample preparation procedure for PIXE elemental analysis on soft tissues

    International Nuclear Information System (INIS)

    Kubica, B.; Kwiatek, W.M.; Dutkiewicz, E.M.; Lekka, M.

    1997-01-01

    Trace element analysis is one of the most important field in analytical chemistry. There are several instrumental techniques which are applied for determinations of microscopic elemental content. The PIXE (Proton Induced X-ray Emission) technique is one of the nuclear techniques that is commonly applied for such purpose due to its multielemental analysis possibilities. The aim of this study was to establish the optimal conditions for target preparation procedure. In this paper two different approaches to the topic are presented and widely discussed. The first approach was the traditional pellet technique and the second one was mineralization procedure. For the analysis soft tissue such as liver was used. Some results are also presented on water samples. (author)

  8. Evaluation of six sample preparation procedures for qualitative and quantitative proteomics analysis of milk fat globule membrane.

    Science.gov (United States)

    Yang, Yongxin; Anderson, Elizabeth; Zhang, Sheng

    2018-04-12

    Proteomic analysis of membrane proteins is challenged by the proteins solubility and detergent incompatibility with MS analysis. No single perfect protocol can be used to comprehensively characterize the proteome of membrane fraction. Here, we used cow milk fat globule membrane (MFGM) proteome analysis to assess six sample preparation procedures including one in-gel and five in-solution digestion approaches prior to LC-MS/MS analysis. The largest number of MFGM proteins were identified by suspension trapping (S-Trap) and filter-aided sample preparation (FASP) methods, followed by acetone precipitation without clean-up of tryptic peptides method. Protein identifications with highest average coverage was achieved by Chloroform/MeOH, in-gel and S-Trap methods. Most distinct proteins were identified by FASP method, followed by S-Trap. Analyses by Venn diagram, principal-component analysis, hierarchical clustering and the abundance ranking of quantitative proteins highlight differences in the MFGM fraction by the all sample preparation procedures. These results reveal the biased proteins/peptides loss occurred in each protocol. In this study, we found several novel proteins that were not observed previously by in-depth proteomics characterization of MFGM fraction in milk. Thus, a combination of multiple procedures with orthologous properties of sample preparation was demonstrated to improve the protein sequence coverage and expression level accuracy of membrane samples. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  9. Sampling procedure, receipt and conservation of water samples to determine environmental radioactivity

    International Nuclear Information System (INIS)

    Herranz, M.; Navarro, E.; Payeras, J.

    2009-01-01

    The present document informs about essential goals, processes and contents that the subgroups Sampling and Samples Preparation and Conservation believe they should be part of the procedure to obtain a correct sampling, receipt, conservation and preparation of samples of continental, marine and waste water before qualifying its radioactive content.

  10. Optimized pre-thinning procedures of ion-beam thinning for TEM sample preparation by magnetorheological polishing.

    Science.gov (United States)

    Luo, Hu; Yin, Shaohui; Zhang, Guanhua; Liu, Chunhui; Tang, Qingchun; Guo, Meijian

    2017-10-01

    Ion-beam-thinning is a well-established sample preparation technique for transmission electron microscopy (TEM), but tedious procedures and labor consuming pre-thinning could seriously reduce its efficiency. In this work, we present a simple pre-thinning technique by using magnetorheological (MR) polishing to replace manual lapping and dimpling, and demonstrate the successful preparation of electron-transparent single crystal silicon samples after MR polishing and single-sided ion milling. Dimples pre-thinned to less than 30 microns and with little mechanical surface damage were repeatedly produced under optimized MR polishing conditions. Samples pre-thinned by both MR polishing and traditional technique were ion-beam thinned from the rear side until perforation, and then observed by optical microscopy and TEM. The results show that the specimen pre-thinned by MR technique was free from dimpling related defects, which were still residual in sample pre-thinned by conventional technique. Nice high-resolution TEM images could be acquired after MR polishing and one side ion-thinning. MR polishing promises to be an adaptable and efficient method for pre-thinning in preparation of TEM specimens, especially for brittle ceramics. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. Collection and preparation of samples for gamma spectrometry

    International Nuclear Information System (INIS)

    Pan Jingquan

    1994-01-01

    The paper presents the basic principles of sample collection and preparation: setting up unified sampling program, methods and procedures, sample packing, transportation and storage, determination of sample quantity, sample pretreatment and preparation of samples to be analysed, etc. for gamma spectrometry. And the paper also describes briefly the main methods and special issues of sampling and preparation for the same environmental and biological samples, such as, air, water, grass, soil and foods

  12. Membrane biofouling characterization: effects of sample preparation procedures on biofilm structure and the microbial community

    KAUST Repository

    Xue, Zheng

    2014-07-15

    Ensuring the quality and reproducibility of results from biofilm structure and microbial community analysis is essential to membrane biofouling studies. This study evaluated the impacts of three sample preparation factors (ie number of buffer rinses, storage time at 4°C, and DNA extraction method) on the downstream analysis of nitrifying biofilms grown on ultrafiltration membranes. Both rinse and storage affected biofilm structure, as suggested by their strong correlation with total biovolume, biofilm thickness, roughness and the spatial distribution of EPS. Significant variations in DNA yields and microbial community diversity were also observed among samples treated by different rinses, storage and DNA extraction methods. For the tested biofilms, two rinses, no storage and DNA extraction with both mechanical and chemical cell lysis from attached biofilm were the optimal sample preparation procedures for obtaining accurate information about biofilm structure, EPS distribution and the microbial community. © 2014 © 2014 Taylor & Francis.

  13. On the development of automatic sample preparation devices

    International Nuclear Information System (INIS)

    Oesselmann, J.

    1987-01-01

    Modern mass spectrometers for stable isotope analysis offer accurate isotope ratio results from gaseous samples (CO 2 , N 2 , H 2 , SO 2 ) in a completely automated fashion. However, most samples of interest either are associated with contaminant gases or the gas has to be liberated by a chemical procedure prior to measurement. In most laboratories this sample preparation step is performed manually. As a consequence, sample throughput is rather low and - despite skilful operation - the preparation procedure varies slightly from one sample to the next affecting mainly the reproducibility of the data. (author)

  14. Sample preparation in alkaline media

    International Nuclear Information System (INIS)

    Nobrega, Joaquim A.; Santos, Mirian C.; Sousa, Rafael A. de; Cadore, Solange; Barnes, Ramon M.; Tatro, Mark

    2006-01-01

    The use of tetramethylammonium hydroxide, tertiary amines and strongly alkaline reagents for sample treatment involving extraction and digestion procedures is discussed in this review. The preparation of slurries is also discussed. Based on literature data, alkaline media offer a good alternative for sample preparation involving an appreciable group of analytes in different types of samples. These reagents are also successfully employed in tailored speciation procedures wherein there is a critical dependence on maintenance of chemical forms. The effects of these reagents on measurements performed using spectroanalytical techniques are discussed. Several undesirable effects on transport and atomization processes necessitate use of the method of standard additions to obtain accurate results. It is also evident that alkaline media can improve the performance of techniques such as inductively coupled plasma mass spectrometry and accessories, such as autosamplers coupled to graphite furnace atomic absorption spectrometers

  15. Green approaches in sample preparation of bioanalytical samples prior to chromatographic analysis.

    Science.gov (United States)

    Filippou, Olga; Bitas, Dimitrios; Samanidou, Victoria

    2017-02-01

    Sample preparation is considered to be the most challenging step of the analytical procedure, since it has an effect on the whole analytical methodology, therefore it contributes significantly to the greenness or lack of it of the entire process. The elimination of the sample treatment steps, pursuing at the same time the reduction of the amount of the sample, strong reductions in consumption of hazardous reagents and energy also maximizing safety for operators and environment, the avoidance of the use of big amount of organic solvents, form the basis for greening sample preparation and analytical methods. In the last decade, the development and utilization of greener and sustainable microextraction techniques is an alternative to classical sample preparation procedures. In this review, the main green microextraction techniques (solid phase microextraction, stir bar sorptive extraction, hollow-fiber liquid phase microextraction, dispersive liquid - liquid microextraction, etc.) will be presented, with special attention to bioanalytical applications of these environment-friendly sample preparation techniques which comply with the green analytical chemistry principles. Copyright © 2016 Elsevier B.V. All rights reserved.

  16. Cytological preparations for molecular analysis: A review of technical procedures, advantages and limitations for referring samples for testing.

    Science.gov (United States)

    da Cunha Santos, G; Saieg, M A; Troncone, G; Zeppa, P

    2018-04-01

    Minimally invasive procedures such as endobronchial ultrasound-guided transbronchial needle aspiration (EBUS-TBNA) must yield not only good quality and quantity of material for morphological assessment, but also an adequate sample for analysis of molecular markers to guide patients to appropriate targeted therapies. In this context, cytopathologists worldwide should be familiar with minimum requirements for refereeing cytological samples for testing. The present manuscript is a review with comprehensive description of the content of the workshop entitled Cytological preparations for molecular analysis: pre-analytical issues for EBUS TBNA, presented at the 40th European Congress of Cytopathology in Liverpool, UK. The present review emphasises the advantages and limitations of different types of cytology substrates used for molecular analysis such as archival smears, liquid-based preparations, archival cytospin preparations and FTA (Flinders Technology Associates) cards, as well as their technical requirements/features. These various types of cytological specimens can be successfully used for an extensive array of molecular studies, but the quality and quantity of extracted nucleic acids rely directly on adequate pre-analytical assessment of those samples. In this setting, cytopathologists must not only be familiar with the different types of specimens and associated technical procedures, but also correctly handle the material provided by minimally invasive procedures, ensuring that there is sufficient amount of material for a precise diagnosis and correct management of the patient through personalised care. © 2018 John Wiley & Sons Ltd.

  17. Standard methods for sampling and sample preparation for gamma spectroscopy

    International Nuclear Information System (INIS)

    Taskaeva, M.; Taskaev, E.; Nikolov, P.

    1993-01-01

    The strategy for sampling and sample preparation is outlined: necessary number of samples; analysis and treatment of the results received; quantity of the analysed material according to the radionuclide concentrations and analytical methods; the minimal quantity and kind of the data needed for making final conclusions and decisions on the base of the results received. This strategy was tested in gamma spectroscopic analysis of radionuclide contamination of the region of Eleshnitsa Uranium Mines. The water samples was taken and stored according to the ASTM D 3370-82. The general sampling procedures were in conformity with the recommendations of ISO 5667. The radionuclides was concentrated by coprecipitation with iron hydroxide and ion exchange. The sampling of soil samples complied with the rules of ASTM C 998, and their sample preparation - with ASTM C 999. After preparation the samples were sealed hermetically and measured. (author)

  18. Innovative methods for inorganic sample preparation

    Energy Technology Data Exchange (ETDEWEB)

    Essling, A.M.; Huff, E.A.; Graczyk, D.G.

    1992-04-01

    Procedures and guidelines are given for the dissolution of a variety of selected materials using fusion, microwave, and Parr bomb techniques. These materials include germanium glass, corium-concrete mixtures, and zeolites. Emphasis is placed on sample-preparation approaches that produce a single master solution suitable for complete multielement characterization of the sample. In addition, data are presented on the soil microwave digestion method approved by the Environmental Protection Agency (EPA). Advantages and disadvantages of each sample-preparation technique are summarized.

  19. Innovative methods for inorganic sample preparation

    International Nuclear Information System (INIS)

    Essling, A.M.; Huff, E.A.; Graczyk, D.G.

    1992-04-01

    Procedures and guidelines are given for the dissolution of a variety of selected materials using fusion, microwave, and Parr bomb techniques. These materials include germanium glass, corium-concrete mixtures, and zeolites. Emphasis is placed on sample-preparation approaches that produce a single master solution suitable for complete multielement characterization of the sample. In addition, data are presented on the soil microwave digestion method approved by the Environmental Protection Agency (EPA). Advantages and disadvantages of each sample-preparation technique are summarized

  20. Procedures for sampling radium-contaminated soils

    International Nuclear Information System (INIS)

    Fleischhauer, H.L.

    1985-10-01

    Two procedures for sampling the surface layer (0 to 15 centimeters) of radium-contaminated soil are recommended for use in remedial action projects. Both procedures adhere to the philosophy that soil samples should have constant geometry and constant volume in order to ensure uniformity. In the first procedure, a ''cookie cutter'' fashioned from pipe or steel plate, is driven to the desired depth by means of a slide hammer, and the sample extracted as a core or plug. The second procedure requires use of a template to outline the sampling area, from which the sample is obtained using a trowel or spoon. Sampling to the desired depth must then be performed incrementally. Selection of one procedure over the other is governed primarily by soil conditions, the cookie cutter being effective in nongravelly soils, and the template procedure appropriate for use in both gravelly and nongravelly soils. In any event, a minimum sample volume of 1000 cubic centimeters is recommended. The step-by-step procedures are accompanied by a description of the minimum requirements for sample documentation. Transport of the soil samples from the field is then addressed in a discussion of the federal regulations for shipping radioactive materials. Interpretation of those regulations, particularly in light of their application to remedial action soil-sampling programs, is provided in the form of guidance and suggested procedures. Due to the complex nature of the regulations, however, there is no guarantee that our interpretations of them are complete or entirely accurate. Preparation of soil samples for radium-226 analysis by means of gamma-ray spectroscopy is described

  1. Sample preparation guidelines for two-dimensional electrophoresis.

    Science.gov (United States)

    Posch, Anton

    2014-12-01

    Sample preparation is one of the key technologies for successful two-dimensional electrophoresis (2DE). Due to the great diversity of protein sample types and sources, no single sample preparation method works with all proteins; for any sample the optimum procedure must be determined empirically. This review is meant to provide a broad overview of the most important principles in sample preparation in order to avoid a multitude of possible pitfalls. Sample preparation protocols from the expert in the field were screened and evaluated. On the basis of these protocols and my own comprehensive practical experience important guidelines are given in this review. The presented guidelines will facilitate straightforward protocol development for researchers new to gel-based proteomics. In addition the available choices are rationalized in order to successfully prepare a protein sample for 2DE separations. The strategies described here are not limited to 2DE and can also be applied to other protein separation techniques.

  2. Laboratory manual on sample preparation procedures for x-ray micro-analysis

    International Nuclear Information System (INIS)

    1997-01-01

    X-ray micro fluorescence is a non-destructive and sensitive method for studying the microscopic distribution of different elements in almost all kinds of samples. Since the beginning of this century, x-rays and electrons have been used for the analysis of many different kinds of material. Techniques which rely on electrons are mainly developed for microscopic studies, and are used in conventional Electron Microscopy (EM) or Scanning Electron Microscopy (SEM), while x-rays are widely used for chemical analysis at the microscopic level. The first chemical analysis by fluorescence spectroscopy using small x-ray beams was conducted in 1928 by Glockner and Schreiber. Since then much work has been devoted to developing different types of optical systems for focusing an x-ray beam, but the efficiency of these systems is still inferior to the conventional electron optical systems. However, even with a poor optical efficiency, the x-ray microbeam has many advantages compared with electron or proton induced x-ray emission methods. These include: The analyses are non-destructive, losses of mass are negligible, and due to the low thermal loading of x-rays, materials which may be thermally degraded can be analysed; Samples can be analysed in air, and no vacuum is required, therefore specimens with volatile components such as water in biological samples, can be imaged at normal pressure and temperature; No charging occurs during analysis and therefore coating of the sample with a conductive layer is not necessary; With these advantages, simpler sample preparation procedures including mounting and preservation can be used

  3. Newly introduced sample preparation techniques: towards miniaturization.

    Science.gov (United States)

    Costa, Rosaria

    2014-01-01

    Sampling and sample preparation are of crucial importance in an analytical procedure, representing quite often a source of errors. The technique chosen for the isolation of analytes greatly affects the success of a chemical determination. On the other hand, growing concerns about environmental and human safety, along with the introduction of international regulations for quality control, have moved the interest of scientists towards specific needs. Newly introduced sample preparation techniques are challenged to meet new criteria: (i) miniaturization, (ii) higher sensitivity and selectivity, and (iii) automation. In this survey, the most recent techniques introduced in the field of sample preparation will be described and discussed, along with many examples of applications.

  4. Soil sample preparation using microwave digestion for uranium analysis

    International Nuclear Information System (INIS)

    Mohagheghi, Amir H.; Preston, Rose; Akbarzadeh, Mansoor; Bakthiar, Steven

    2000-01-01

    A new sample preparation procedure has been developed for digestion of soil samples for uranium analysis. The technique employs a microwave oven digestion system to digest the sample and to prepare it for separation chemistry and analysis. The method significantly reduces the volume of acids used, eliminates a large fraction of acid vapor emissions, and speeds up the analysis time. The samples are analyzed by four separate techniques: Gamma Spectrometry, Alpha Spectroscopy using the open digestion method, Kinetic Phosphorescence Analysis (KPA) using open digestion, and KPA by Microwave digestion technique. The results for various analytical methods are compared and used to confirm the validity of the new procedure. The details of the preparation technique along with its benefits are discussed

  5. Preparation of honey sample for tritium monitoring

    International Nuclear Information System (INIS)

    Chen Bingru; Wang Chenlian; Wang Weihua

    1989-01-01

    The method of preparation of honey sample for tritium monitoring was described. The equipments consist of an air and honey supply system, a quartz combustor with CM-type monolithic combustion catalyst and a condensation system. In the equipments, honey sample was converted into cooling water by the distilling, cracking and carbonizing procedures for tritium counting. The recovery ratio is 99.0 ± 4.5 percent for tritiated water and 96.0 ± 2.0 for tritiated organic compounds. It is a feasible preparing method for the total tritium monitoring in honey sample

  6. Procedures for cryogenic X-ray ptychographic imaging of biological samples.

    Science.gov (United States)

    Yusuf, M; Zhang, F; Chen, B; Bhartiya, A; Cunnea, K; Wagner, U; Cacho-Nerin, F; Schwenke, J; Robinson, I K

    2017-03-01

    Biological sample-preparation procedures have been developed for imaging human chromosomes under cryogenic conditions. A new experimental setup, developed for imaging frozen samples using beamline I13 at Diamond Light Source, is described. This manuscript describes the equipment and experimental procedures as well as the authors' first ptychographic reconstructions using X-rays.

  7. A novel sample preparation procedure for effect-directed analysis of micro-contaminants of emerging concern in surface waters.

    Science.gov (United States)

    Osorio, Victoria; Schriks, Merijn; Vughs, Dennis; de Voogt, Pim; Kolkman, Annemieke

    2018-08-15

    A novel sample preparation procedure relying on Solid Phase Extraction (SPE) combining different sorbent materials on a sequential-based cartridge was optimized and validated for the enrichment of 117 widely diverse contaminants of emerging concern (CECs) from surface waters (SW) and further combined chemical and biological analysis on subsequent extracts. A liquid chromatography coupled to high resolution tandem mass spectrometry LC-(HR)MS/MS protocol was optimized and validated for the quantitative analysis of organic CECs in SW extracts. A battery of in vitro CALUX bioassays for the assessment of endocrine, metabolic and genotoxic interference and oxidative stress were performed on the same SW extracts. Satisfactory recoveries ([70-130]%) and precision ( 0.99) over three orders of magnitude. Instrumental limits of detection and method limits of quantification were of [1-96] pg injected and [0.1-58] ng/L, respectively; while corresponding intra-day and inter-day precision did not exceed 11% and 20%. The developed procedure was successfully applied for the combined chemical and toxicological assessment of SW intended for drinking water supply. Levels of compounds varied from < 10 ng/L to < 500 ng/L. Endocrine (i.e. estrogenic and anti-androgenic) and metabolic interference responses were observed. Given the demonstrated reliability of the validated sample preparation method, the authors propose its integration in an effect-directed analysis procedure for a proper evaluation of SW quality and hazard assessment of CECs. Copyright © 2018 Elsevier B.V. All rights reserved.

  8. Procedures for cryogenic X-ray ptychographic imaging of biological samples

    Directory of Open Access Journals (Sweden)

    M. Yusuf

    2017-03-01

    Full Text Available Biological sample-preparation procedures have been developed for imaging human chromosomes under cryogenic conditions. A new experimental setup, developed for imaging frozen samples using beamline I13 at Diamond Light Source, is described. This manuscript describes the equipment and experimental procedures as well as the authors' first ptychographic reconstructions using X-rays.

  9. Advances in modern sample preparation techniques using microwaves assisted chemistry for metal species determination (W1)

    International Nuclear Information System (INIS)

    Ponard, O.F.X.

    2002-01-01

    Full text: Sample preparation has long been the bottleneck of environmental analysis for both total and species specific analysis. Digestion, extraction and preparation of the analytes are relying on a series of chemical reactions. The introduction of microwave assisted sample preparation has first been viewed as a mean to accelerate the kinetics of digestion of the matrix for total elements and fast samples preparation procedures. However, the extensive development and success of microwave digestion procedures in total elemental analysis has now allowed to have a larger insight of the perspectives offered by this technique. Microwave technologies now offer to have a precise control of the temperature and indirectly control the reaction kinetics taking place during the sample preparation procedures. Microwave assisted chemistry permits to perform simultaneously the fundamental steps required for metal species extraction and derivatization. The number of sample preparation steps used for organotin or organomercury species have been reduced to one and the total time of sample preparation brought down for a few hours to some minutes. Further, the developments of GC/ICP/MS techniques allow to routinely use speciated isotopic dilution methods has internal probe of the chemical reactions. These new approaches allow us to use the addition of the labeled species for isotopic dilution as a mean to evaluate and follow the chemical processes taking place during the extraction procedure. These procedures will help us to understand and check for the stability of the analytes during the chemistry of the sample preparation procedure and bring some insights of the chemistry taking place during the extraction. Understanding the different mechanisms involved in the sample preparation steps will allow us in return to further improve all theses procedures and bring us to the horizon of 'on-line sample preparation and detection'. (author)

  10. Sample preparation

    International Nuclear Information System (INIS)

    Anon.

    1992-01-01

    Sample preparation prior to HPLC analysis is certainly one of the most important steps to consider in trace or ultratrace analysis. For many years scientists have tried to simplify the sample preparation process. It is rarely possible to inject a neat liquid sample or a sample where preparation may not be any more complex than dissolution of the sample in a given solvent. The last process alone can remove insoluble materials, which is especially helpful with the samples in complex matrices if other interactions do not affect extraction. Here, it is very likely a large number of components will not dissolve and are, therefore, eliminated by a simple filtration process. In most cases, the process of sample preparation is not as simple as dissolution of the component interest. At times, enrichment is necessary, that is, the component of interest is present in very large volume or mass of material. It needs to be concentrated in some manner so a small volume of the concentrated or enriched sample can be injected into HPLC. 88 refs

  11. Use of robotic systems for radiochemical sample changing and for analytical sample preparation

    International Nuclear Information System (INIS)

    Delmastro, J.R.; Hartenstein, S.D.; Wade, M.A.

    1989-01-01

    Two uses of the Perkin-Elmer (PE) robotic system will be presented. In the first, a PE robot functions as an automatic sample changer for up to five low energy photon spectrometry (LEPS) detectors operated with a Nuclear Data ND 6700 system. The entire system, including the robot, is controlled by an IBM PC-AT using software written in compiled BASIC. Problems associated with the development of the system and modifications to the robot will be presented. In the second, an evaluation study was performed to assess the abilities of the PE robotic system for performing complex analytical sample preparation procedures. For this study, a robotic system based upon the PE robot and auxiliary devices was constructed and programmed to perform the preparation of final product samples (UO 3 ) for accountability and impurity specification analyses. These procedures require sample dissolution, dilution, and liquid-liquid extraction steps. The results of an in-depth evaluation of all system components will be presented

  12. Sample processing procedures and radiocarbon dating

    International Nuclear Information System (INIS)

    Svetlik, Ivo; Tomaskova, Lenka; Dreslerova, Dagmar

    2010-01-01

    The article outlines radiocarbon dating routines and highlights the potential and limitations of this method. The author's institutions have been jointly running a conventional radiocarbon dating laboratory using the international CRL code. A procedure based on the synthesis of benzene is used. Small samples are sent abroad for dating because no AMS instrumentation is available in the Czech Republic so far. Our laboratory plans to introduce routines for the processing of milligram samples and preparation of graphitized targets for AMS

  13. Quantitating morphological changes in biological samples during scanning electron microscopy sample preparation with correlative super-resolution microscopy.

    Science.gov (United States)

    Zhang, Ying; Huang, Tao; Jorgens, Danielle M; Nickerson, Andrew; Lin, Li-Jung; Pelz, Joshua; Gray, Joe W; López, Claudia S; Nan, Xiaolin

    2017-01-01

    Sample preparation is critical to biological electron microscopy (EM), and there have been continuous efforts on optimizing the procedures to best preserve structures of interest in the sample. However, a quantitative characterization of the morphological changes associated with each step in EM sample preparation is currently lacking. Using correlative EM and superresolution microscopy (SRM), we have examined the effects of different drying methods as well as osmium tetroxide (OsO4) post-fixation on cell morphology during scanning electron microscopy (SEM) sample preparation. Here, SRM images of the sample acquired under hydrated conditions were used as a baseline for evaluating morphological changes as the sample went through SEM sample processing. We found that both chemical drying and critical point drying lead to a mild cellular boundary retraction of ~60 nm. Post-fixation by OsO4 causes at least 40 nm additional boundary retraction. We also found that coating coverslips with adhesion molecules such as fibronectin prior to cell plating helps reduce cell distortion from OsO4 post-fixation. These quantitative measurements offer useful information for identifying causes of cell distortions in SEM sample preparation and improving current procedures.

  14. Collection and preparation of wet and dry stream-sediment samples

    International Nuclear Information System (INIS)

    Puchlik, K.

    1977-03-01

    Lawrence Livermore Laboratory is responsible for the Hydrogeochemistry and Stream Sediment Reconnaissance (HSSR) program for uranium in the seven far western states. The work thus far has concentrated on the arid to semi-arid regions of the West and this paper discusses the collection and preparation of sediment samples in the Basin and Range province. The sample collection and preparation procedures described here may not be applicable to other parts of the far western states or other areas. These procedures also differ somewhat from those used by the other three laboratories involved in the HSSR program

  15. FFTF operations procedures preparation guide. Revision 2

    International Nuclear Information System (INIS)

    1976-12-01

    The Guide is intended to provide guidelines for the initial preparation of FFTF Operating Procedures. The Procedures Preparation Guide was developed from the plan presented and approved in the FFTF Reactor Plant Procedures Plan, PC-1, Revision 3

  16. Focused-microwave-assisted sample preparation (M8)

    International Nuclear Information System (INIS)

    Nobrega, J.A.; Santos, D.M.; Trevizan, L.C.; Costa, L.M.; Nogueira, A.R.A.

    2002-01-01

    Full text: Focused-microwave-assisted sample preparation is a suitable strategy when dealing with high masses of organic samples. However, the final acid concentration of the digestate can difficult routine analytical measurements using spectroscopic techniques. Acids could be evaporated, but this step could be slow even when using microwave-assisted heating and requires a scrubber system for acid vapor collection and neutralization. We are investigating two procedures to decrease the acid concentration of digestates. The first one is based on acid vapor phase digestion of samples contained in PTFE devices' inserted into the microwave flask. The acid solution is heated by absorption of microwave radiation, then the acid vapor partially condenses in the upper part of the reaction flask and it is partially collected in each sample container. Calcium, Fe, Mg, Mn, and Zn were quantitatively recovered in samples of animal and vegetable tissues. Better recoveries were attained when adding a small volume of sodium hypochlorite to the sample. This effect is probably related to the generation of chlorine in the sample container after collecting condensed acid. The second procedure developed is based on the gradual addition of liquid samples to a previously heated acid digestion mixture. This procedure was successfully applied for digestion of milk, fruit juices, and red wine. The main advantage is the possibility of digesting up to four-fold more sample using up to ten-fold lower amounts of concentrated acids. Results obtained using both digestion procedures and measurements by ICP-OES with axial view will be presented. (author)

  17. Robotic sample preparation for radiochemical plutonium and americium analyses

    International Nuclear Information System (INIS)

    Stalnaker, N.; Beugelsdijk, T.; Thurston, A.; Quintana, J.

    1985-01-01

    A Zymate robotic system has been assembled and programmed to prepare samples for plutonium and americium analyses by radioactivity counting. The system performs two procedures: a simple dilution procedure and a TTA (xylene) extraction of plutonium. To perform the procedures, the robotic system executes 11 unit operations such as weighing, pipetting, mixing, etc. Approximately 150 programs, which require 64 kilobytes of memory, control the system. The system is now being tested with high-purity plutonium metal and plutonium oxide samples. Our studies indicate that the system can give results that agree within 5% at the 95% confidence level with determinations performed manually. 1 ref., 1 fig., 1 tab

  18. New trends in sample preparation techniques for environmental analysis.

    Science.gov (United States)

    Ribeiro, Cláudia; Ribeiro, Ana Rita; Maia, Alexandra S; Gonçalves, Virgínia M F; Tiritan, Maria Elizabeth

    2014-01-01

    Environmental samples include a wide variety of complex matrices, with low concentrations of analytes and presence of several interferences. Sample preparation is a critical step and the main source of uncertainties in the analysis of environmental samples, and it is usually laborious, high cost, time consuming, and polluting. In this context, there is increasing interest in developing faster, cost-effective, and environmentally friendly sample preparation techniques. Recently, new methods have been developed and optimized in order to miniaturize extraction steps, to reduce solvent consumption or become solventless, and to automate systems. This review attempts to present an overview of the fundamentals, procedure, and application of the most recently developed sample preparation techniques for the extraction, cleanup, and concentration of organic pollutants from environmental samples. These techniques include: solid phase microextraction, on-line solid phase extraction, microextraction by packed sorbent, dispersive liquid-liquid microextraction, and QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe).

  19. Final Report for X-ray Diffraction Sample Preparation Method Development

    Energy Technology Data Exchange (ETDEWEB)

    Ely, T. M. [Hanford Site (HNF), Richland, WA (United States); Meznarich, H. K. [Hanford Site (HNF), Richland, WA (United States); Valero, T. [Hanford Site (HNF), Richland, WA (United States)

    2018-01-30

    WRPS-1500790, “X-ray Diffraction Saltcake Sample Preparation Method Development Plan/Procedure,” was originally prepared with the intent of improving the specimen preparation methodology used to generate saltcake specimens suitable for XRD-based solid phase characterization. At the time that this test plan document was originally developed, packed powder in cavity supports with collodion binder was the established XRD specimen preparation method. An alternate specimen preparation method less vulnerable, if not completely invulnerable to preferred orientation effects, was desired as a replacement for the method.

  20. Witness sample preparation for measuring antireflection coatings.

    Science.gov (United States)

    Willey, Ronald R

    2014-02-01

    Measurement of antireflection coating of witness samples from across the worldwide industry has been shown to have excess variability from a sampling taken for the OSA Topical Meeting on Optical Interference Coatings: Measurement Problem. Various sample preparation techniques have been discussed with their limitations, and a preferred technique is recommended with its justification, calibration procedures, and limitations. The common practice of grinding the second side to reduce its reflection is less than satisfactory. One recommended practice is to paint the polished second side, which reduces its reflection to almost zero. A method to evaluate the suitability of given paints is also described.

  1. TEM sample preparation by FIB for carbon nanotube interconnects

    International Nuclear Information System (INIS)

    Ke, Xiaoxing; Bals, Sara; Romo Negreira, Ainhoa; Hantschel, Thomas; Bender, Hugo; Van Tendeloo, Gustaaf

    2009-01-01

    A powerful method to study carbon nanotubes (CNTs) grown in patterned substrates for potential interconnects applications is transmission electron microscopy (TEM). However, high-quality TEM samples are necessary for such a study. Here, TEM specimen preparation by focused ion beam (FIB) has been used to obtain lamellae of patterned samples containing CNTs grown inside contact holes. A dual-cap Pt protection layer and an extensive 5 kV cleaning procedure are applied in order to preserve the CNTs and avoid deterioration during milling. TEM results show that the inner shell structure of the carbon nanotubes has been preserved, which proves that focused ion beam is a useful technique to prepare TEM samples of CNT interconnects.

  2. TEM sample preparation by FIB for carbon nanotube interconnects

    Energy Technology Data Exchange (ETDEWEB)

    Ke, Xiaoxing, E-mail: xiaoxing.ke@ua.ac.be [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Bals, Sara [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium); Romo Negreira, Ainhoa [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Metallurgy and Materials Engineering Department, KU Leuven, Kasteelpark Arenberg 44, Leuven B-3001 (Belgium); Hantschel, Thomas; Bender, Hugo [IMEC, Kapeldreef 75, B-3001 Leuven (Belgium); Van Tendeloo, Gustaaf [EMAT, University of Antwerp, Groenenborgerlaan 171, B-2020 Antwerp (Belgium)

    2009-10-15

    A powerful method to study carbon nanotubes (CNTs) grown in patterned substrates for potential interconnects applications is transmission electron microscopy (TEM). However, high-quality TEM samples are necessary for such a study. Here, TEM specimen preparation by focused ion beam (FIB) has been used to obtain lamellae of patterned samples containing CNTs grown inside contact holes. A dual-cap Pt protection layer and an extensive 5 kV cleaning procedure are applied in order to preserve the CNTs and avoid deterioration during milling. TEM results show that the inner shell structure of the carbon nanotubes has been preserved, which proves that focused ion beam is a useful technique to prepare TEM samples of CNT interconnects.

  3. Notes on sample preparation of food: food of plant and animal origins, and daily meals

    International Nuclear Information System (INIS)

    Heilgeist, M.

    1992-01-01

    The procedure of food sample preparation to determine their specific radioactivity, analogous to chemical residue analysis, is laid down in the relevant sets of regulations. Several procedural steps of sample preparation of single food and composite food are dealt with. The sample size necessary for gamma spectroscopy and Sr-89/Sr-90 analysis, and the incineration step to enrich radionuclides are explained. Finally, enrichment by freeze drying of the high-volatile radionuclide I-131 is considered. (orig.) [de

  4. Sampling and sample handling procedures for priority pollutants in surface coal mining wastewaters. [Detailed list to be analyzed for

    Energy Technology Data Exchange (ETDEWEB)

    Hayden, R. S.; Johnson, D. O.; Henricks, J. D.

    1979-03-01

    The report describes the procedures used by Argonne National Laboratory to sample surface coal mine effluents in order to obtain field and laboratory data on 110 organic compounds or classes of compounds and 14 metals and minerals that are known as priority pollutants, plus 5-day biochemical oxygen demand (BOD/sub 5/), total organic carbon (TOC), chemical oxygen demand (COD), total dissolved solids (TDS), and total suspended solids (TSS). Included are directions for preparation of sampling containers and equipment, methods of sampling and sample preservation, and field and laboratory protocols, including chain-of-custody procedures. Actual analytical procedures are not described, but their sources are referenced.

  5. Traceability and measurement uncertainty in sample preparation (W5)

    International Nuclear Information System (INIS)

    Wegscheider, W.; Walner, U.; Moser, J.

    2002-01-01

    Full text: Very few chemical measurements are being made directly on the object of interest and sample preparation is thus the rule rather than the exception in daily practice. Unfortunately the operations undertaken in the course of sample preparation are prone to rendering a sample useless for the purpose of interpreting a measurement performed on it, as it might not represent the original and relevant status any longer. Sample preparation along with sampling itself constitutes therefore a procedure that leads to a loss of representation of the original specimen or population. On the other hand it is also not sufficient to confine aspects of traceability and measurement uncertainty to the ultimate measurement, as the key purpose of measuring is to supply adequate data for some kind of decision, be it in production, in health, in the environment, or indeed in any other circumstance. These considerations have led to severe confusion in the community as to what traceability really means in chemistry. CITAC and EURACHEM have only recently issued a preliminary document that clarifies these issues and gives a firm handle on the future development of quality assurance in analytical chemistry. In this talk it will be attempted to outline the general ideas and procedures that lead to traceability of analytical chemical results accompanied by valid statements of their uncertainty. It will be argued that the central element in achieving these goals is a well-designed validation study that frequently goes beyond those requirements currently laid out in official documents. (author)

  6. Sample preparation of energy materials for X-ray nanotomography with micromanipulation.

    Science.gov (United States)

    Chen-Wiegart, Yu-chen Karen; Camino, Fernando E; Wang, Jun

    2014-06-06

    X-ray nanotomography presents an unprecedented opportunity to study energy storage/conversion materials at nanometer scales in three dimensions, with both elemental and chemical sensitivity. A critical step in obtaining high-quality X-ray nanotomography data is reliable sample preparation to ensure that the entire sample fits within the field of view of the X-ray microscope. Although focused-ion-beam lift-out has previously been used for large sample (few to tens of microns) preparation, a difficult undercut and lift-out procedure results in a time-consuming sample preparation process. Herein, we propose a much simpler and direct sample preparation method to resolve the issues that block the view of the sample base after milling and during the lift-out process. This method is applied on a solid-oxide fuel cell and a lithium-ion battery electrode, before numerous critical 3D morphological parameters are extracted, which are highly relevant to their electrochemical performance. A broad application of this method for microstructure study with X-ray nanotomography is discussed and presented. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  7. Recent developments in sample preparation and data pre-treatment in metabonomics research.

    Science.gov (United States)

    Li, Ning; Song, Yi peng; Tang, Huiru; Wang, Yulan

    2016-01-01

    Metabonomics is a powerful approach for biomarker discovery and an effective tool for pinpointing endpoint metabolic effects of external stimuli, such as pathogens and disease development. Due to its wide applications, metabonomics is required to deal with various biological samples of different properties. Hence sample preparation and corresponding data pre-treatment become important factors in ensuring validity of an investigation. In this review, we summarize some recent developments in metabonomics sample preparation and data-pretreatment procedures. Copyright © 2015 Elsevier Inc. All rights reserved.

  8. Atomic absorption determination of metals in soils using ultrasonic sample preparation

    International Nuclear Information System (INIS)

    Chmilenko, F.A.; Smityuk, N.M.; Baklanov, A.N.

    2002-01-01

    It was shown that ultrasonic treatment accelerates sample preparation of soil extracts from chernozem into different solvents by a factor of 6 to 60. These extracts are used for the atomic absorption determination of soluble species of Cd, Co, Cr, Cu, Ni, Pb, and Zn. The optimum ultrasound parameters (frequency, intensity, and treatment time) were found for preparing soil extracts containing analytes in concentrations required in agrochemical procedures. Different extractants used to extract soluble heavy metals from soils of an ordinary chernozem type in agrochemical procedures using ultrasonic treatment were classified in accordance with the element nature [ru

  9. Role of microextraction sampling procedures in forensic toxicology.

    Science.gov (United States)

    Barroso, Mário; Moreno, Ivo; da Fonseca, Beatriz; Queiroz, João António; Gallardo, Eugenia

    2012-07-01

    The last two decades have provided analysts with more sensitive technology, enabling scientists from all analytical fields to see what they were not able to see just a few years ago. This increased sensitivity has allowed drug detection at very low concentrations and testing in unconventional samples (e.g., hair, oral fluid and sweat), where despite having low analyte concentrations has also led to a reduction in sample size. Along with this reduction, and as a result of the use of excessive amounts of potentially toxic organic solvents (with the subsequent environmental pollution and costs associated with their proper disposal), there has been a growing tendency to use miniaturized sampling techniques. Those sampling procedures allow reducing organic solvent consumption to a minimum and at the same time provide a rapid, simple and cost-effective approach. In addition, it is possible to get at least some degree of automation when using these techniques, which will enhance sample throughput. Those miniaturized sample preparation techniques may be roughly categorized in solid-phase and liquid-phase microextraction, depending on the nature of the analyte. This paper reviews recently published literature on the use of microextraction sampling procedures, with a special focus on the field of forensic toxicology.

  10. Preparation of biological samples for transmission X-ray microanalysis: a review of alternative procedures to the use of sectioned material

    International Nuclear Information System (INIS)

    Sigee, D.C.

    1988-01-01

    Although transmission X-ray microanalysis of biological material has traditionally been carried out mainly on sectioned preparations, a number of alternative procedures exist. These are considered under three major headings - whole cell preparations, analysis of cell homogenates and biological fluids, and applications of the technique to microsamples of purified biochemicals. These three aspects provide a continuous range of investigative level - from the cellular to the molecular. The use of X-ray microanalysis with whole cell preparations is considered in reference to eukaryote (animal) cells and prokaryotes - where it has particular potential in environmental studies on bacteria. In the case of cell homogenates and biological fluids, the technique has been used mainly with microdroplets of animal material. The use of X-ray microanalysis with purified biochemicals is considered in relation to both particulate and non-particulate samples. In the latter category, the application of this technique for analysis of thin films of metalloprotein is particularly emphasised. It is concluded that wider use could be made of the range of preparative techniques available - both within a particular investigation, and in diverse fields of study. Transmission X-ray microanalysis has implications for environmental, physiological and molecular biology as well as cell biology

  11. Pretreatment procedures applied to samples to be analysed by neutron activation analysis at CDTN/CNEN

    International Nuclear Information System (INIS)

    Francisco, Dovenir; Menezes, Maria Angela de Barros Correia

    2009-01-01

    The neutron activation technique - using several methods - has been applied in 80% of the analytical demand of Division for Reactor and Analytical Techniques at CDTN/CNEN, Belo Horizonte, Minas Gerais. This scenario emphasizes the responsibility of the Laboratory to provide and assure the quality of the measurements. The first step to assure the results quality is the preparation of the samples. Therefore, this paper describes the experimental procedures adopted at CDTN/CNEN in order to uniform conditions of analysis and to avoid contaminations by elements present everywhere. Some of the procedures are based on methods described in the literature; others are based on many years of experience preparing samples from many kinds of matrices. The procedures described are related to geological material - soil, sediment, rock, gems, clay, archaeological ceramics and ore - biological materials - hair, fish, plants, food - water, etc. Analytical results in sediment samples are shown as n example pointing out the efficiency of the experimental procedure. (author)

  12. TCLP Preparation and Analysis of K East Basin Composite Sludge Samples

    International Nuclear Information System (INIS)

    Silvers, K.L.; Wagner, J.J.; Steele, R.T.

    2000-01-01

    Sludge samples from the Hanford K East Basin were analyzed by the Toxicity Characterization Leaching Procedure (TCLP) to assist in the appropriate Resource Conservation and Recovery Act (RCIL4) designation of this material. Sludge samples were collected by Fluor Hanford, Inc. using the consolidated sludge sampling system (system that allows collection of a single sample from multiple sample locations). These samples were shipped to the Postirradiation Testing Laboratory (PTL, 327 Building) and then transferred to the Pacific Northwest National Laboratory (PNNL) Radiochemical Processing Laboratory (RPL, 325 Building) for recovery and testing. Two sludge composites were prepared, using the consolidated sludge samples, to represent K East canister sludge (sample KC Can Comp) and K East floor sludge (sample KC Floor Comp). Each composite was extracted in duplicate and analyzed in duplicate following pre-approved(a) TCLP extraction and analyses procedures. In addition, these samples and duplicates were analyzed for total RCRA metals (via acid digestion preparation). The work was conducted in accordance with the requirements of the Hanford Analytical Quality Assurance Requirements Document (HASQARD). A PNNL Quality Assurance Program compliant with J HASQARD was implemented for this effort. The results from the TCLP analyses showed that all RCRA metal concentrations were less than the TCLP limits for both the canister and floor composite samples and their respective duplicates

  13. Magnetic separation techniques in sample preparation for biological analysis: a review.

    Science.gov (United States)

    He, Jincan; Huang, Meiying; Wang, Dongmei; Zhang, Zhuomin; Li, Gongke

    2014-12-01

    Sample preparation is a fundamental and essential step in almost all the analytical procedures, especially for the analysis of complex samples like biological and environmental samples. In past decades, with advantages of superparamagnetic property, good biocompatibility and high binding capacity, functionalized magnetic materials have been widely applied in various processes of sample preparation for biological analysis. In this paper, the recent advancements of magnetic separation techniques based on magnetic materials in the field of sample preparation for biological analysis were reviewed. The strategy of magnetic separation techniques was summarized. The synthesis, stabilization and bio-functionalization of magnetic nanoparticles were reviewed in detail. Characterization of magnetic materials was also summarized. Moreover, the applications of magnetic separation techniques for the enrichment of protein, nucleic acid, cell, bioactive compound and immobilization of enzyme were described. Finally, the existed problems and possible trends of magnetic separation techniques for biological analysis in the future were proposed. Copyright © 2014 Elsevier B.V. All rights reserved.

  14. Specified assurance level sampling procedure

    International Nuclear Information System (INIS)

    Willner, O.

    1980-11-01

    In the nuclear industry design specifications for certain quality characteristics require that the final product be inspected by a sampling plan which can demonstrate product conformance to stated assurance levels. The Specified Assurance Level (SAL) Sampling Procedure has been developed to permit the direct selection of attribute sampling plans which can meet commonly used assurance levels. The SAL procedure contains sampling plans which yield the minimum sample size at stated assurance levels. The SAL procedure also provides sampling plans with acceptance numbers ranging from 0 to 10, thus, making available to the user a wide choice of plans all designed to comply with a stated assurance level

  15. New Sample Preparation Method for Quantification of Phenolic Compounds of Tea (Camellia sinensis L. Kuntze: A Polyphenol Rich Plant

    Directory of Open Access Journals (Sweden)

    P. A. Nimal Punyasiri

    2015-01-01

    Full Text Available Chemical analysis of the Sri Lankan tea (Camellia sinensis, L. germplasm would immensely contribute to the success of the tea breeding programme. However, the polyphenols, particularly catechins (flavan-3-ols, are readily prone to oxidation in the conventional method of sample preparation. Therefore, optimization of the present sample preparation methodology for the profiling of metabolites is much important. Two sample preparation methodologies were compared, fresh leaves (as in the conventional procedures and freeze-dried leaves (a new procedure, for quantification of major metabolites by employing two cultivars, one is known to be high quality black tea and the other low quality black tea. The amounts of major metabolites such as catechins, caffeine, gallic acid, and theobromine, recorded in the new sampling procedure via freeze-dried leaves, were significantly higher than those recorded in the conventional sample preparation procedure. Additionally new method required less amount of leaf sample for analysis of major metabolites and facilitates storage of samples until analysis. The freeze-dried method would be useful for high throughput analysis of large number of samples in shorter period without chemical deterioration starting from the point of harvest until usage. Hence, this method is more suitable for metabolite profiling of tea as well as other phenol rich plants.

  16. Standard operating procedure for combustion of 14C - samples with OX-500 biological material oxidizer

    International Nuclear Information System (INIS)

    Nashriyah Mat.

    1995-01-01

    This procedure is for the purpose of safe operation of OX-500 biological material oxidizer. For ease of operation, the operation flow chart (including testing the system and sample combustion) and end of day maintenance flow chart were simplified. The front view, diagrams and switches are duly copied from operating manual. Steps on sample preparation are also included for biotic and a biotic samples. This operating procedure is subjected to future reviews

  17. 40 CFR 761.323 - Sample preparation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 30 2010-07-01 2010-07-01 false Sample preparation. 761.323 Section... Remediation Waste Samples § 761.323 Sample preparation. (a) The comparison study requires analysis of a... concentrations by dilution. Any excess material resulting from the preparation of these samples, which is not...

  18. Sample preparation in foodomic analyses.

    Science.gov (United States)

    Martinović, Tamara; Šrajer Gajdošik, Martina; Josić, Djuro

    2018-04-16

    Representative sampling and adequate sample preparation are key factors for successful performance of further steps in foodomic analyses, as well as for correct data interpretation. Incorrect sampling and improper sample preparation can be sources of severe bias in foodomic analyses. It is well known that both wrong sampling and sample treatment cannot be corrected anymore. These, in the past frequently neglected facts, are now taken into consideration, and the progress in sampling and sample preparation in foodomics is reviewed here. We report the use of highly sophisticated instruments for both high-performance and high-throughput analyses, as well as miniaturization and the use of laboratory robotics in metabolomics, proteomics, peptidomics and genomics. This article is protected by copyright. All rights reserved. This article is protected by copyright. All rights reserved.

  19. Selecting Sample Preparation Workflows for Mass Spectrometry-Based Proteomic and Phosphoproteomic Analysis of Patient Samples with Acute Myeloid Leukemia.

    Science.gov (United States)

    Hernandez-Valladares, Maria; Aasebø, Elise; Selheim, Frode; Berven, Frode S; Bruserud, Øystein

    2016-08-22

    Global mass spectrometry (MS)-based proteomic and phosphoproteomic studies of acute myeloid leukemia (AML) biomarkers represent a powerful strategy to identify and confirm proteins and their phosphorylated modifications that could be applied in diagnosis and prognosis, as a support for individual treatment regimens and selection of patients for bone marrow transplant. MS-based studies require optimal and reproducible workflows that allow a satisfactory coverage of the proteome and its modifications. Preparation of samples for global MS analysis is a crucial step and it usually requires method testing, tuning and optimization. Different proteomic workflows that have been used to prepare AML patient samples for global MS analysis usually include a standard protein in-solution digestion procedure with a urea-based lysis buffer. The enrichment of phosphopeptides from AML patient samples has previously been carried out either with immobilized metal affinity chromatography (IMAC) or metal oxide affinity chromatography (MOAC). We have recently tested several methods of sample preparation for MS analysis of the AML proteome and phosphoproteome and introduced filter-aided sample preparation (FASP) as a superior methodology for the sensitive and reproducible generation of peptides from patient samples. FASP-prepared peptides can be further fractionated or IMAC-enriched for proteome or phosphoproteome analyses. Herein, we will review both in-solution and FASP-based sample preparation workflows and encourage the use of the latter for the highest protein and phosphorylation coverage and reproducibility.

  20. Skin sample preparation by collagenase digestion for diclofenac quantification using LC-MS/MS after topical application.

    Science.gov (United States)

    Nirogi, Ramakrishna; Padala, Naga Surya Prakash; Boggavarapu, Rajesh Kumar; Kalaikadhiban, Ilayaraja; Ajjala, Devender Reddy; Bhyrapuneni, Gopinadh; Muddana, Nageswara Rao

    2016-06-01

    Skin is the target site to evaluate the pharmacokinetic parameters of topical applications. Sample preparation is one of the influential steps in the bioanalysis of drugs in the skin. Evaluation of dermatopharmacokinetics at preclinical stage is challenging due to lack of proper sample preparation method. There is a need for an efficient sample preparation procedure for quantification of drugs in the skin using LC-MS/MS. The skin samples treated with collagenase followed by homogenization using a bead beater represents a best-fit method resulting in uniform homogenate for reproducible results. A new approach involving enzymatic treatment and mechanical homogenization techniques were evaluated for efficient sample preparation of skin samples in the bioanalysis.

  1. A comparative examination of sample treatment procedures for ICAP-AES analysis of biological tissue

    Science.gov (United States)

    De Boer, J. L. M.; Maessen, F. J. M. J.

    The objective of this study was to contribute to the evaluation of existing sample preparation procedures for ICAP-AES analysis of biological material. Performance characteristics were established of current digestion procedures comprising extraction, solubilization, pressure digestion, and wet and dry ashing methods. Apart from accuracy and precision, a number of criteria of special interest for the analytical practice was applied. As a test sample served SRM bovine liver. In this material six elements were simultaneously determined. Results showed that every procedure has its defects and advantages. Hence, unambiguous recommendation of standard digestion procedures can be made only when taking into account the specific analytical problem.

  2. An Integrated Solution-Based Rapid Sample Preparation Procedure for the Analysis of N-Glycans From Therapeutic Monoclonal Antibodies.

    Science.gov (United States)

    Aich, Udayanath; Liu, Aston; Lakbub, Jude; Mozdzanowski, Jacek; Byrne, Michael; Shah, Nilesh; Galosy, Sybille; Patel, Pramthesh; Bam, Narendra

    2016-03-01

    Consistent glycosylation in therapeutic monoclonal antibodies is a major concern in the biopharmaceutical industry as it impacts the drug's safety and efficacy and manufacturing processes. Large numbers of samples are created for the analysis of glycans during various stages of recombinant proteins drug development. Profiling and quantifying protein N-glycosylation is important but extremely challenging due to its microheterogeneity and more importantly the limitations of existing time-consuming sample preparation methods. Thus, a quantitative method with fast sample preparation is crucial for understanding, controlling, and modifying the glycoform variance in therapeutic monoclonal antibody development. Presented here is a rapid and highly quantitative method for the analysis of N-glycans from monoclonal antibodies. The method comprises a simple and fast solution-based sample preparation method that uses nontoxic reducing reagents for direct labeling of N-glycans. The complete work flow for the preparation of fluorescently labeled N-glycans takes a total of 3 h with less than 30 min needed for the release of N-glycans from monoclonal antibody samples. Copyright © 2016 American Pharmacists Association®. Published by Elsevier Inc. All rights reserved.

  3. Microextraction sample preparation techniques in biomedical analysis.

    Science.gov (United States)

    Szultka, Malgorzata; Pomastowski, Pawel; Railean-Plugaru, Viorica; Buszewski, Boguslaw

    2014-11-01

    Biologically active compounds are found in biological samples at relatively low concentration levels. The sample preparation of target compounds from biological, pharmaceutical, environmental, and food matrices is one of the most time-consuming steps in the analytical procedure. The microextraction techniques are dominant. Metabolomic studies also require application of proper analytical technique for the determination of endogenic metabolites present in biological matrix on trace concentration levels. Due to the reproducibility of data, precision, relatively low cost of the appropriate analysis, simplicity of the determination, and the possibility of direct combination of those techniques with other methods (combination types on-line and off-line), they have become the most widespread in routine determinations. Additionally, sample pretreatment procedures have to be more selective, cheap, quick, and environmentally friendly. This review summarizes the current achievements and applications of microextraction techniques. The main aim is to deal with the utilization of different types of sorbents for microextraction and emphasize the use of new synthesized sorbents as well as to bring together studies concerning the systematic approach to method development. This review is dedicated to the description of microextraction techniques and their application in biomedical analysis. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Sample preparation techniques of biological material for isotope analysis

    International Nuclear Information System (INIS)

    Axmann, H.; Sebastianelli, A.; Arrillaga, J.L.

    1990-01-01

    Sample preparation is an essential step in all isotope-aided experiments but often it is not given enough attention. The methods of sample preparation are very important to obtain reliable and precise analytical data and for further interpretation of results. The size of a sample required for chemical analysis is usually very small (10mg-1500mg). On the other hand the amount of harvested plant material from plots in a field experiment is often bulky (several kilograms) and the entire sample is too large for processing. In addition, while approaching maturity many crops show not only differences in physical consistency but also a non-uniformity in 15 N content among plant parts, requiring a plant fractionation or separation into parts (vegetative and reproductive) e.g. shoots and spikes, in case of small grain cereals, shoots and pods in case of grain legumes and tops and roots or beets (including crown) in case of sugar beet, etc. In any case the ultimate goal of these procedures is to obtain representative subsample harvested from greenhouse or field experiments for chemical analysis. Before harvesting an isotopic-aided experiment the method of sampling has to be selected. It should be based on the type of information required in relation to the objectives of the research and the availability of resources (staff, sample preparation equipment, analytical facilities, chemicals and supplies, etc.). 10 refs, 3 figs, 3 tabs

  5. Open focused microwave-assisted sample preparation for rapid total and mercury species determination in environmental solid samples

    OpenAIRE

    Tseng, C. M.; Garraud, H.; Amouroux, D.; Donard, O. F. X.; de Diego, A.

    1998-01-01

    This paper describes rapid, simple microwave-assisted leaching/ digestion procedures for total and mercury species determination in sediment samples and biomaterials. An open focused microwave system allowed the sample preparation time to be dramatically reduced to only 24 min when a power of 40-80 W was applied. Quantitative leaching of methylmercury from sediments by HNO3 solution and complete dissolution of biomaterials by an alkaline solution, such as 25% TMAH solution, were obtained. Met...

  6. Polymeric ionic liquid-based portable tip microextraction device for on-site sample preparation of water samples.

    Science.gov (United States)

    Chen, Lei; Pei, Junxian; Huang, Xiaojia; Lu, Min

    2018-06-05

    On-site sample preparation is highly desired because it avoids the transportation of large-volume samples and ensures the accuracy of the analytical results. In this work, a portable prototype of tip microextraction device (TMD) was designed and developed for on-site sample pretreatment. The assembly procedure of TMD is quite simple. Firstly, polymeric ionic liquid (PIL)-based adsorbent was in-situ prepared in a pipette tip. After that, the tip was connected with a syringe which was driven by a bidirectional motor. The flow rates in adsorption and desorption steps were controlled accurately by the motor. To evaluate the practicability of the developed device, the TMD was used to on-site sample preparation of waters and combined with high-performance liquid chromatography with diode array detection to measure trace estrogens in water samples. Under the most favorable conditions, the limits of detection (LODs, S/N = 3) for the target analytes were in the range of 4.9-22 ng/L, with good coefficients of determination. Confirmatory study well evidences that the extraction performance of TMD is comparable to that of the traditional laboratory solid-phase extraction process, but the proposed TMD is more simple and convenient. At the same time, the TMD avoids complicated sampling and transferring steps of large-volume water samples. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Selecting Sample Preparation Workflows for Mass Spectrometry-Based Proteomic and Phosphoproteomic Analysis of Patient Samples with Acute Myeloid Leukemia

    Directory of Open Access Journals (Sweden)

    Maria Hernandez-Valladares

    2016-08-01

    Full Text Available Global mass spectrometry (MS-based proteomic and phosphoproteomic studies of acute myeloid leukemia (AML biomarkers represent a powerful strategy to identify and confirm proteins and their phosphorylated modifications that could be applied in diagnosis and prognosis, as a support for individual treatment regimens and selection of patients for bone marrow transplant. MS-based studies require optimal and reproducible workflows that allow a satisfactory coverage of the proteome and its modifications. Preparation of samples for global MS analysis is a crucial step and it usually requires method testing, tuning and optimization. Different proteomic workflows that have been used to prepare AML patient samples for global MS analysis usually include a standard protein in-solution digestion procedure with a urea-based lysis buffer. The enrichment of phosphopeptides from AML patient samples has previously been carried out either with immobilized metal affinity chromatography (IMAC or metal oxide affinity chromatography (MOAC. We have recently tested several methods of sample preparation for MS analysis of the AML proteome and phosphoproteome and introduced filter-aided sample preparation (FASP as a superior methodology for the sensitive and reproducible generation of peptides from patient samples. FASP-prepared peptides can be further fractionated or IMAC-enriched for proteome or phosphoproteome analyses. Herein, we will review both in-solution and FASP-based sample preparation workflows and encourage the use of the latter for the highest protein and phosphorylation coverage and reproducibility.

  8. Synthesis and application of magnetic molecularly imprinted polymers in sample preparation.

    Science.gov (United States)

    Huang, Shuyao; Xu, Jianqiao; Zheng, Jiating; Zhu, Fang; Xie, Lijun; Ouyang, Gangfeng

    2018-04-12

    Magnetic molecularly imprinted polymers (MMIPs) have superior advantages in sample pretreatment because of their high selectivity for target analytes and the fast and easy isolation from samples. To meet the demand of both good magnetic property and good extraction performance, MMIPs with various structures, from traditional core-shell structures to novel composite structures with a larger specific surface area and more accessible binding sites, are fabricated by different preparation technologies. Moreover, as the molecularly imprinted polymer (MIP) layers determine the affinity, selectivity, and saturated adsorption amount of MMIPs, the development and innovation of the MIP layer are attracting attention and are reviewed here. Many studies that used MMIPs as sorbents in dispersive solid-phase extraction of complex samples, including environmental, food, and biofluid samples, are summarized. Graphical abstract The application of magnetic molecularly imprinted polymers (MIPs) in the sample preparation procedure improves the analytical performances for complex samples. MITs molecular imprinting technologies.

  9. Final LDRD report : development of sample preparation methods for ChIPMA-based imaging mass spectrometry of tissue samples.

    Energy Technology Data Exchange (ETDEWEB)

    Maharrey, Sean P.; Highley, Aaron M.; Behrens, Richard, Jr.; Wiese-Smith, Deneille

    2007-12-01

    The objective of this short-term LDRD project was to acquire the tools needed to use our chemical imaging precision mass analyzer (ChIPMA) instrument to analyze tissue samples. This effort was an outgrowth of discussions with oncologists on the need to find the cellular origin of signals in mass spectra of serum samples, which provide biomarkers for ovarian cancer. The ultimate goal would be to collect chemical images of biopsy samples allowing the chemical images of diseased and nondiseased sections of a sample to be compared. The equipment needed to prepare tissue samples have been acquired and built. This equipment includes an cyro-ultramicrotome for preparing thin sections of samples and a coating unit. The coating unit uses an electrospray system to deposit small droplets of a UV-photo absorbing compound on the surface of the tissue samples. Both units are operational. The tissue sample must be coated with the organic compound to enable matrix assisted laser desorption/ionization (MALDI) and matrix enhanced secondary ion mass spectrometry (ME-SIMS) measurements with the ChIPMA instrument Initial plans to test the sample preparation using human tissue samples required development of administrative procedures beyond the scope of this LDRD. Hence, it was decided to make two types of measurements: (1) Testing the spatial resolution of ME-SIMS by preparing a substrate coated with a mixture of an organic matrix and a bio standard and etching a defined pattern in the coating using a liquid metal ion beam, and (2) preparing and imaging C. elegans worms. Difficulties arose in sectioning the C. elegans for analysis and funds and time to overcome these difficulties were not available in this project. The facilities are now available for preparing biological samples for analysis with the ChIPMA instrument. Some further investment of time and resources in sample preparation should make this a useful tool for chemical imaging applications.

  10. Membrane biofouling characterization: effects of sample preparation procedures on biofilm structure and the microbial community

    KAUST Repository

    Xue, Zheng; Lu, Huijie; Liu, Wen-Tso

    2014-01-01

    Ensuring the quality and reproducibility of results from biofilm structure and microbial community analysis is essential to membrane biofouling studies. This study evaluated the impacts of three sample preparation factors (ie number of buffer rinses

  11. Preparation of rock samples for measurement of the thermal neutron macroscopic absorption cross-section

    International Nuclear Information System (INIS)

    Czubek, J.A.; Burda, J.; Drozdowicz, K.; Igielski, A.; Kowalik, W.; Krynicka-Drozdowicz, E.; Woznicka, U.

    1986-03-01

    Preparation of rock samples for the measurement of the thermal neutron macroscopic absorption cross-section in small cylindrical two-region systems by a pulsed technique is presented. Requirements which should be fulfilled during the preparation of the samples due to physical assumptions of the method are given. A cylindrical vessel is filled with crushed rock and saturated with a medium strongly absorbing thermal neutrons. Water solutions of boric acid of well-known macroscopic absorption cross-section are used. Mass contributions of the components in the sample are specified. This is necessary for the calculation of the thermal neutron macroscopic absorption cross-section of the rock matrix. The conditions necessary for assuring the required accuracy of the measurement are given and the detailed procedure of preparation of the rock sample is described. (author)

  12. RECOMMENDED OPERATING PROCEDURE NO. 56: COLLECTION OF GASEOUS GRAB SAMPLES FROM COMBUSTION SOURCES FOR NITROUS OXIDE MEASUREMENT

    Science.gov (United States)

    The document is a recommended operating procedure, prepare or use in research activities conducted by EPA's Air and Energy Engineering Research Laboratory (AEERL). The procedure applies to the collection of gaseous grab samples from fossil fuel combustion sources for subsequent a...

  13. Synchrotron/crystal sample preparation

    Science.gov (United States)

    Johnson, R. Barry

    1993-01-01

    The Center for Applied Optics (CAO) of the University of Alabama in Huntsville (UAH) prepared this final report entitled 'Synchrotron/Crystal Sample Preparation' in completion of contract NAS8-38609, Delivery Order No. 53. Hughes Danbury Optical Systems (HDOS) is manufacturing the Advanced X-ray Astrophysics Facility (AXAF) mirrors. These thin-walled, grazing incidence, Wolter Type-1 mirrors, varying in diameter from 1.2 to 0.68 meters, must be ground and polished using state-of-the-art techniques in order to prevent undue stress due to damage or the presence of crystals and inclusions. The effect of crystals on the polishing and grinding process must also be understood. This involves coating special samples of Zerodur and measuring the reflectivity of the coatings in a synchrotron system. In order to gain the understanding needed on the effect of the Zerodur crystals by the grinding and polishing process, UAH prepared glass samples by cutting, grinding, etching, and polishing as required to meet specifications for witness bars for synchrotron measurements and for investigations of crystals embedded in Zerodur. UAH then characterized these samples for subsurface damage and surface roughness and figure.

  14. Development of a sample preparation system for AMS radiocarbon dating at CRICH, Korea

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Myung-Jin; Lee, Byeong-Cheol; Lim, Eun-Soo [Cultural Research Institute of Chungcheong Heritage, Gongju (Korea, Republic of); Hong, Duk-Geun [Kangwon National University, Chuncheon (Korea, Republic of); Park, Soon-Bal [Chungnam National University, Daejeon (Korea, Republic of); Youn, Min-Young [Seoul National University, Seoul (Korea, Republic of)

    2010-01-15

    We developed a sample preparation system for radiocarbon dating by using AMS measurement at Cultural Research Institute of Chungcheong Heritage, Korea. From the investigation of the reduction process, the optimum graphitization temperature was chosen as 625 .deg. C. Using Aldrich graphite powder of 0.75 {+-} 0.023 pMC, the background value of our preparation system was controlled at a low level. The robustness against chemical treatment and contamination was also observed from samples of Oxalic acid II and IAEA-C4. The resultant values, 134.04 {+-} 0.99 pMC and 0.38 {+-} 0.043 pMC, were in good agreement with the consensus values. Based on comparison, our conventional ages agreed very well with those of Beta Analytic Co. and SNU-AMS. No memory effect existed in the preparation system. Therefore, we concluded that the sample preparation system was operated in a stable manner and that the basic radiocarbon dating procedures were completely verified.

  15. Challenges of sample preparation for cross sectional EBSD analysis of electrodeposited nickel films

    DEFF Research Database (Denmark)

    Alimadadi, Hossein; Pantleon, Karen

    2009-01-01

    Thorough microstructure and crystallographic orientation analysis of thin films by means of electron backscatter diffraction requires cross section preparation of the film-substrate compound. During careful preparation, changes of the rather non-stable as-deposited microstructure must be avoided....... Different procedures for sample preparation including mechanical grinding and polishing, electropolishing and focused ion beam milling have been applied to a nickel film electrodeposited on top of an amorphous Ni-P layer on a Cu-substrate. Reliable EBSD analysis of the whole cross section can be obtained...

  16. Evaluation of sample preparation protocols for spider venom profiling by MALDI-TOF MS.

    Science.gov (United States)

    Bočánek, Ondřej; Šedo, Ondrej; Pekár, Stano; Zdráhal, Zbyněk

    2017-07-01

    Spider venoms are highly complex mixtures containing biologically active substances with potential for use in biotechnology or pharmacology. Fingerprinting of venoms by Matrix-Assisted Laser Desorption-Ionization - Time of Flight Mass Spectrometry (MALDI-TOF MS) is a thriving technology, enabling the rapid detection of peptide/protein components that can provide comparative information. In this study, we evaluated the effects of sample preparation procedures on MALDI-TOF mass spectral quality to establish a protocol providing the most reliable analytical outputs. We adopted initial sample preparation conditions from studies already published in this field. Three different MALDI matrixes, three matrix solvents, two sample deposition methods, and different acid concentrations were tested. As a model sample, venom from Brachypelma albopilosa was used. The mass spectra were evaluated on the basis of absolute and relative signal intensities, and signal resolution. By conducting three series of analyses at three weekly intervals, the reproducibility of the mass spectra were assessed as a crucial factor in the selection for optimum conditions. A sample preparation protocol based on the use of an HCCA matrix dissolved in 50% acetonitrile with 2.5% TFA deposited onto the target by the dried-droplet method was found to provide the best results in terms of information yield and repeatability. We propose that this protocol should be followed as a standard procedure, enabling the comparative assessment of MALDI-TOF MS spider venom fingerprints. Copyright © 2017 Elsevier Ltd. All rights reserved.

  17. The Influence of Sample Drying Procedures on Mercury Concentrations Analyzed in Soils

    Czech Academy of Sciences Publication Activity Database

    Hojdová, Maria; Rohovec, Jan; Chrastný, V.; Penížek, V.; Navrátil, Tomáš

    2015-01-01

    Roč. 94, č. 5 (2015), s. 570-576 ISSN 0007-4861 R&D Projects: GA ČR GP526/09/P404; GA ČR(CZ) GAP210/11/1369 Institutional support: RVO:67985831 Keywords : sample preparation * drying procedures * microbial activity * freeze-drying * contamination Subject RIV: DD - Geochemistry Impact factor: 1.191, year: 2015

  18. [Sample preparation and bioanalysis in mass spectrometry].

    Science.gov (United States)

    Bourgogne, Emmanuel; Wagner, Michel

    2015-01-01

    The quantitative analysis of compounds of clinical interest of low molecular weight (sample preparation. Sample preparation is a crucial part of chemical/biological analysis and in a sense is considered the bottleneck of the whole analytical process. The main objectives of sample preparation are the removal of potential interferences, analyte preconcentration, and converting (if needed) the analyte into a more suitable form for detection or separation. Without chromatographic separation, endogenous compounds, co-eluted products may affect a quantitative method in mass spectrometry performance. This work focuses on three distinct parts. First, quantitative bioanalysis will be defined, different matrices and sample preparation techniques currently used in bioanalysis by mass spectrometry of/for small molecules of clinical interest in biological fluids. In a second step the goals of sample preparation will be described. Finally, in a third step, sample preparation strategies will be made either directly ("dilute and shoot") or after precipitation.

  19. METALLOGRAPHIC SAMPLE PREPARATION STATION-CONSTRUCTIVE CONCEPT

    Directory of Open Access Journals (Sweden)

    AVRAM Florin Timotei

    2016-11-01

    Full Text Available In this paper we propose to present the issues involved in the case of the constructive conception of a station for metallographic sample preparation. This station is destined for laboratory work. The metallographic station is composed of a robot ABB IRB1600, a metallographic microscope, a gripping device, a manipulator, a laboratory grinding and polishing machine. The robot will be used for manipulation of the sample preparation and the manipulator take the sample preparation for processing.

  20. An easy and fast procedure for the determination of Ca, Cu, Fe, Mn, Mg, Na, K and Si in biodiesel by ICP OES using emulsification as sample preparation strategy

    OpenAIRE

    Lisboa, Meibel T.; Clasen, Caroline D.; Vellar, Daiane C. de Sousa; Oreste, Eliézer Q.; Saint'Pierre, Tatiana D.; Ribeiro, Anderson S.; Vieira, Mariana A.

    2014-01-01

    It is presented an alternative procedure for preparation of biodiesel samples for elemental determination by inductively coupled plasma optical emission spectrometry (ICP OES), based on the sample (10% m/v) emulsion formation with formic acid (15% v/v) and Triton X-100 (0.1% m/v). These concentrations were optimized and the stability of emulsified aqueous standards and samples was found to be of at least 3 h. Experimental conditions (1500 W of RF power and 0.5 L min-1 of Ar nebulizer flow rat...

  1. Review of sample preparation techniques for the analysis of pesticide residues in soil.

    Science.gov (United States)

    Tadeo, José L; Pérez, Rosa Ana; Albero, Beatriz; García-Valcárcel, Ana I; Sánchez-Brunete, Consuelo

    2012-01-01

    This paper reviews the sample preparation techniques used for the analysis of pesticides in soil. The present status and recent advances made during the last 5 years in these methods are discussed. The analysis of pesticide residues in soil requires the extraction of analytes from this matrix, followed by a cleanup procedure, when necessary, prior to their instrumental determination. The optimization of sample preparation is a very important part of the method development that can reduce the analysis time, the amount of solvent, and the size of samples. This review considers all aspects of sample preparation, including extraction and cleanup. Classical extraction techniques, such as shaking, Soxhlet, and ultrasonic-assisted extraction, and modern techniques like pressurized liquid extraction, microwave-assisted extraction, solid-phase microextraction and QuEChERS (Quick, Easy, Cheap, Effective, Rugged, and Safe) are reviewed. The different cleanup strategies applied for the purification of soil extracts are also discussed. In addition, the application of these techniques to environmental studies is considered.

  2. Preparing Monodisperse Macromolecular Samples for Successful Biological Small-Angle X-ray and Neutron Scattering Experiments

    Science.gov (United States)

    Jeffries, Cy M.; Graewert, Melissa A.; Blanchet, Clément E.; Langley, David B.; Whitten, Andrew E.; Svergun, Dmitri I

    2017-01-01

    Small-angle X-ray and neutron scattering (SAXS and SANS) are techniques used to extract structural parameters and determine the overall structures and shapes of biological macromolecules, complexes and assemblies in solution. The scattering intensities measured from a sample contain contributions from all atoms within the illuminated sample volume including the solvent and buffer components as well as the macromolecules of interest. In order to obtain structural information, it is essential to prepare an exactly matched solvent blank so that background scattering contributions can be accurately subtracted from the sample scattering to obtain the net scattering from the macromolecules in the sample. In addition, sample heterogeneity caused by contaminants, aggregates, mismatched solvents, radiation damage or other factors can severely influence and complicate data analysis so it is essential that the samples are pure and monodisperse for the duration of the experiment. This Protocol outlines the basic physics of SAXS and SANS and reveals how the underlying conceptual principles of the techniques ultimately ‘translate’ into practical laboratory guidance for the production of samples of sufficiently high quality for scattering experiments. The procedure describes how to prepare and characterize protein and nucleic acid samples for both SAXS and SANS using gel electrophoresis, size exclusion chromatography and light scattering. Also included are procedures specific to X-rays (in-line size exclusion chromatography SAXS) and neutrons, specifically preparing samples for contrast matching/variation experiments and deuterium labeling of proteins. PMID:27711050

  3. Sample Preparation for Determination of Biological Thiols by Liquid Chromatography and Electromigration Techniques

    OpenAIRE

    Bald, Edward

    2004-01-01

    Wydrukowano z dostarczonych Wydawnictwu UŁ gotowych materiałów Majority of the bioanalytical or environmental methods do not use just one chromatografie or electrophoretic step, but rather involve several sample pretreatment steps which simplfy the matrix, and often preconcentrate and chemically modify the analytes. This work surveys typical procedures for sample preparation for most commonly analyzed biofluids with particular emphasis placed on chemical derivatization of su...

  4. An improved ashing procedure for biologic sample

    Energy Technology Data Exchange (ETDEWEB)

    Zongmei, Wu [Zhejiang Province Enviromental Radiation Monitoring Centre (China)

    1992-07-01

    The classical ashing procedure in muffle was modified for biologic samples. In the modified procedure the door of muffle was open in the duration of ashing process, the ashing was accelerated and the ashing product quality was comparable to that the classical procedure. The modified procedure is suitable for ashing biologic samples in large batches.

  5. An improved ashing procedure for biologic sample

    International Nuclear Information System (INIS)

    Wu Zongmei

    1992-01-01

    The classical ashing procedure in muffle was modified for biologic samples. In the modified procedure the door of muffle was open in the duration of ashing process, the ashing was accelerated and the ashing product quality was comparable to that the classical procedure. The modified procedure is suitable for ashing biologic samples in large batches

  6. Development of Radioanalytical and Microanalytical Procedures for the Determination of Actinides in Environmental Samples

    International Nuclear Information System (INIS)

    Macsik, Zsuzsanna; Vajda, Nora; Bene, Balazs; Varga, Zsolt

    2008-01-01

    A radio-analytical procedure has been developed for the simultaneous determination of actinides in swipe samples by alpha-spectrometry after the separation of the actinides by extraction chromatography. The procedure is based on the complete decomposition of the sample by destruction with microwave digestion or ashing in furnace. Actinides are separated on an extraction chromatographic column filled with TRU resin (product of Eichrom Industries Inc.). Alpha sources prepared from the separated fractions of americium, plutonium, thorium and uranium are counted by alpha spectrometry. Micro-analytical procedure is being developed for the location and identification of individual particles containing fissile material using solid state nuclear track detectors. The parameters of alpha and fission track detection have been optimized and a procedure has been elaborated to locate the particles on the sample by defining the coordinates of the tracks created by the particles on the track detector. Development of a procedure is planned to separate the located particles using micromanipulator and these particles will be examined individually by different micro- and radio-analytical techniques. (authors)

  7. Development of Radioanalytical and Microanalytical Procedures for the Determination of Actinides in Environmental Samples

    Energy Technology Data Exchange (ETDEWEB)

    Macsik, Zsuzsanna [Institute of Nuclear Techniques, Moegyetem rakpart 9, H-1111 Budapest (Hungary); Vajda, Nora [RadAnal Ltd., Bimbo ut 119/a, H-1026 Budapest (Hungary); Bene, Balazs [National Institute of Standards and Technology, Gaithersburg, MD 20899 (United States); Varga, Zsolt [Institute of Isotopes, Konkoly-Thege M. ut 29-33, H-1121 Budapest (Hungary)

    2008-07-01

    A radio-analytical procedure has been developed for the simultaneous determination of actinides in swipe samples by alpha-spectrometry after the separation of the actinides by extraction chromatography. The procedure is based on the complete decomposition of the sample by destruction with microwave digestion or ashing in furnace. Actinides are separated on an extraction chromatographic column filled with TRU resin (product of Eichrom Industries Inc.). Alpha sources prepared from the separated fractions of americium, plutonium, thorium and uranium are counted by alpha spectrometry. Micro-analytical procedure is being developed for the location and identification of individual particles containing fissile material using solid state nuclear track detectors. The parameters of alpha and fission track detection have been optimized and a procedure has been elaborated to locate the particles on the sample by defining the coordinates of the tracks created by the particles on the track detector. Development of a procedure is planned to separate the located particles using micromanipulator and these particles will be examined individually by different micro- and radio-analytical techniques. (authors)

  8. Collection and preparation of water samples for hydrogeochemical reconnaissance

    International Nuclear Information System (INIS)

    Baucom, E.I.; Ferguson, R.B.; Wallace, R.M.

    1977-01-01

    A method based on ion exchange and neutron activation analysis (NAA) was developed and field-tested to determine uranium over the range 0.02 to 10,000 ppb in natural water using a single procedure. Water samples are filtered in the field using a specially-designed one-liter filter apparatus pressurized to 40 psig with an inert gas. The filtered water is treated with a high purity, mixed cation-anion resin in the hydronium-hydroxide form. All ions are removed from solution under the strong driving force of the neutralization reaction. Anionic, cationic, and natural complexes of uranium can be concentrated with this method. Field tests showed greater than 95 percent recovery of 13 elements analyzed (including greater than 99 percent recovery of uranium) and greater than or equal to 90 percent recovery of 4 other elements. Uranium collected on the resin was quantitatively determined by NAA. Coefficient of variation for sampling plus analysis was less than 20 percent for samples containing more than 0.1 ppb uranium. Advantages of this method include: (1) wide dynamic range, (2) low detection limit for uranium (0.02 ppb), (3) high precision and accuracy, (4) relatively low cost, (5) high-yield recovery from low-level aqueous samples without risk of loss to containers, (6) decreased risk of significant sample contamination compared with other low-level methods, (7) production of stable samples suitable for retrievable storage, and(8) concentration of other ions that can be determined by NAA. This paper presents (1) background regarding development of procedures for sample collection and preparation, (2) results of development programs, (3) description of equipment and field procedures, and (4) preliminary conclusions regarding use of this technology for hydrogeochemical reconnaissance for uranium

  9. Highly Reproducible Automated Proteomics Sample Preparation Workflow for Quantitative Mass Spectrometry.

    Science.gov (United States)

    Fu, Qin; Kowalski, Michael P; Mastali, Mitra; Parker, Sarah J; Sobhani, Kimia; van den Broek, Irene; Hunter, Christie L; Van Eyk, Jennifer E

    2018-01-05

    Sample preparation for protein quantification by mass spectrometry requires multiple processing steps including denaturation, reduction, alkylation, protease digestion, and peptide cleanup. Scaling these procedures for the analysis of numerous complex biological samples can be tedious and time-consuming, as there are many liquid transfer steps and timed reactions where technical variations can be introduced and propagated. We established an automated sample preparation workflow with a total processing time for 96 samples of 5 h, including a 2 h incubation with trypsin. Peptide cleanup is accomplished by online diversion during the LC/MS/MS analysis. In a selected reaction monitoring (SRM) assay targeting 6 plasma biomarkers and spiked β-galactosidase, mean intraday and interday cyclic voltammograms (CVs) for 5 serum and 5 plasma samples over 5 days were samples repeated on 3 separate days had total CVs below 20%. Similar results were obtained when the workflow was transferred to a second site: 93% of peptides had CVs below 20%. An automated trypsin digestion workflow yields uniformly processed samples in less than 5 h. Reproducible quantification of peptides was observed across replicates, days, instruments, and laboratory sites, demonstrating the broad applicability of this approach.

  10. Preparation and validation of gross alpha/beta samples used in EML's quality assessment program

    International Nuclear Information System (INIS)

    Scarpitta, S.C.

    1997-10-01

    A set of water and filter samples have been incorporated into the existing Environmental Measurements Laboratory's (EML) Quality Assessment Program (QAP) for gross alpha/beta determinations by participating DOE laboratories. The participating laboratories are evaluated by comparing their results with the EML value. The preferred EML method for measuring water and filter samples, described in this report, uses gas flow proportional counters with 2 in. detectors. Procedures for sample preparation, quality control and instrument calibration are presented. Liquid scintillation (LS) counting is an alternative technique that is suitable for quantifying both the alpha ( 241 Am, 230 Th and 238 Pu) and beta ( 90 Sr/ 90 Y) activity concentrations in the solutions used to prepare the QAP water and air filter samples. Three LS counting techniques (Cerenkov, dual dpm and full spectrum analysis) are compared. These techniques may be used to validate the activity concentrations of each component in the alpha/beta solution before the QAP samples are actually prepared

  11. [Standard sample preparation method for quick determination of trace elements in plastic].

    Science.gov (United States)

    Yao, Wen-Qing; Zong, Rui-Long; Zhu, Yong-Fa

    2011-08-01

    Reference sample was prepared by masterbatch method, containing heavy metals with known concentration of electronic information products (plastic), the repeatability and precision were determined, and reference sample preparation procedures were established. X-Ray fluorescence spectroscopy (XRF) analysis method was used to determine the repeatability and uncertainty in the analysis of the sample of heavy metals and bromine element. The working curve and the metrical methods for the reference sample were carried out. The results showed that the use of the method in the 200-2000 mg x kg(-1) concentration range for Hg, Pb, Cr and Br elements, and in the 20-200 mg x kg(-1) range for Cd elements, exhibited a very good linear relationship, and the repeatability of analysis methods for six times is good. In testing the circuit board ICB288G and ICB288 from the Mitsubishi Heavy Industry Company, results agreed with the recommended values.

  12. An overview of sample preparation procedures for LC-MS multiclass antibiotic determination in environmental and food samples.

    Science.gov (United States)

    Moreno-Bondi, María Cruz; Marazuela, María Dolores; Herranz, Sonia; Rodriguez, Erika

    2009-10-01

    Antibiotics are a class of pharmaceuticals that are of great interest due to the large volumes of these substances that are consumed in both human and veterinary medicine, and due to their status as the agents responsible for bacterial resistance. They can be present in foodstuffs and in environmental samples as multicomponent chemical mixtures that exhibit a wide range of mechanisms of action. Moreover, they can be transformed into different metabolites by the action of microorganisms, as well as by other physical or chemical means, resulting in mixtures with higher ecotoxicities and risks to human health than those of the individual compounds. Therefore, there is growing interest in the availability of multiclass methods for the analysis of antimicrobial mixtures in environmental and food samples at very low concentrations. Liquid chromatography (LC) has become the technique of choice for multiclass analysis, especially when coupled to mass spectrometry (LC-MS) and tandem MS (LC-MS(2)). However, due to the complexity of the matrix, in most cases an extraction step for sample clean-up and preconcentration is required before analysis in order to achieve the required sensitivities. This paper reviews the most recent developments and applications of multiclass antimicrobial determination in environmental and food matrices, emphasizing the practical aspects of sample preparation for the simultaneous extraction of antimicrobials from the selected samples. Future trends in the application of LC-MS-based techniques to multiclass antibiotic analysis are also presented.

  13. Effort versus Reward: Preparing Samples for Fungal Community Characterization in High-Throughput Sequencing Surveys of Soils.

    Directory of Open Access Journals (Sweden)

    Zewei Song

    Full Text Available Next generation fungal amplicon sequencing is being used with increasing frequency to study fungal diversity in various ecosystems; however, the influence of sample preparation on the characterization of fungal community is poorly understood. We investigated the effects of four procedural modifications to library preparation for high-throughput sequencing (HTS. The following treatments were considered: 1 the amount of soil used in DNA extraction, 2 the inclusion of additional steps (freeze/thaw cycles, sonication, or hot water bath incubation in the extraction procedure, 3 the amount of DNA template used in PCR, and 4 the effect of sample pooling, either physically or computationally. Soils from two different ecosystems in Minnesota, USA, one prairie and one forest site, were used to assess the generality of our results. The first three treatments did not significantly influence observed fungal OTU richness or community structure at either site. Physical pooling captured more OTU richness compared to individual samples, but total OTU richness at each site was highest when individual samples were computationally combined. We conclude that standard extraction kit protocols are well optimized for fungal HTS surveys, but because sample pooling can significantly influence OTU richness estimates, it is important to carefully consider the study aims when planning sampling procedures.

  14. Collection and preparation of samples for Agency's programme of intercalibration methods and procedures for measurement of environmental radioactivity

    International Nuclear Information System (INIS)

    Patel, B.

    1975-12-01

    In the period of 1971-1975 several samples of marine sediment and organisms were collected from the Bombay Harbour Bay as well as from the vicinity of the Tarapur nuclear power station in order to supply the materials for preparing intercalibration samples for radionuclides measurements. All samples collected were freeze-dried and homogenized prior to the dispatch to the Monaco Laboratory, where final homogenization and the homogeneity tests were carried out. Altogether 2 marine organisms and 3 marine sediments were supplied during this period. The materials supplied were proved to be useful to prepare intercalibration samples for radionuclide measurements in the levels for monitoring operations. Based on these materials several intercalibration exercises were successfully conducted. This work thus formed a basis for bringing the better comparability of radionuclide measurements in marine environmental samples in an international scale

  15. Bovine liver sample preparation and micro-homogeneity study for Cu and Zn determination by solid sampling electrothermal atomic absorption spectrometry

    International Nuclear Information System (INIS)

    Nomura, Cassiana S.; Silva, Cintia S.; Nogueira, Ana R.A.; Oliveira, Pedro V.

    2005-01-01

    This work describes a systematic study for the bovine liver sample preparation for Cu and Zn determination by solid sampling electrothermal atomic absorption spectrometry. The main parameters investigated were sample drying, grinding process, particle size, sample size, microsample homogeneity, and their relationship with the precision and accuracy of the method. A bovine liver sample was prepared using different drying procedures: (1) freeze drying, and (2) drying in a household microwave oven followed by drying in a stove at 60 deg. C until constant mass. Ball and cryogenic mills were used for grinding. Less sensitive wavelengths for Cu (216.5 nm) and Zn (307.6 nm), and Zeeman-based three-field background correction for Cu were used to diminish the sensitivities. The pyrolysis and atomization temperatures adopted were 1000 deg. C and 2300 deg. C for Cu, and 700 deg. C and 1700 deg. C for Zn, respectively. For both elements, it was possible to calibrate the spectrometer with aqueous solutions. The use of 250 μg of W + 200 μg of Rh as permanent chemical modifier was imperative for Zn. Under these conditions, the characteristic mass and detection limit were 1.4 ng and 1.6 ng for Cu, and 2.8 ng and 1.3 ng for Zn, respectively. The results showed good agreement (95% confidence level) for homogeneity of the entire material (> 200 mg) when the sample was dried in microwave/stove and ground in a cryogenic mill. The microsample homogeneity study showed that Zn is more dependent on the sample pretreatment than Cu. The bovine liver sample prepared in microwave/stove and ground in a cryogenic mill presented results with the lowest relative standard deviation for Cu than Zn. Good accuracy and precision were observed for bovine liver masses higher than 40 μg for Cu and 30 μg for Zn. The concentrations of Cu and Zn in the prepared bovine liver sample were 223 mg kg - 1 and 128 mg kg - 1 , respectively. The relative standard deviations were lower than 6% (n = 5). The

  16. Soil Sampling Operating Procedure

    Science.gov (United States)

    EPA Region 4 Science and Ecosystem Support Division (SESD) document that describes general and specific procedures, methods, and considerations when collecting soil samples for field screening or laboratory analysis.

  17. [Sample preparation methods for chromatographic analysis of organic components in atmospheric particulate matter].

    Science.gov (United States)

    Hao, Liang; Wu, Dapeng; Guan, Yafeng

    2014-09-01

    The determination of organic composition in atmospheric particulate matter (PM) is of great importance in understanding how PM affects human health, environment, climate, and ecosystem. Organic components are also the scientific basis for emission source tracking, PM regulation and risk management. Therefore, the molecular characterization of the organic fraction of PM has become one of the priority research issues in the field of environmental analysis. Due to the extreme complexity of PM samples, chromatographic methods have been the chief selection. The common procedure for the analysis of organic components in PM includes several steps: sample collection on the fiber filters, sample preparation (transform the sample into a form suitable for chromatographic analysis), analysis by chromatographic methods. Among these steps, the sample preparation methods will largely determine the throughput and the data quality. Solvent extraction methods followed by sample pretreatment (e. g. pre-separation, derivatization, pre-concentration) have long been used for PM sample analysis, and thermal desorption methods have also mainly focused on the non-polar organic component analysis in PM. In this paper, the sample preparation methods prior to chromatographic analysis of organic components in PM are reviewed comprehensively, and the corresponding merits and limitations of each method are also briefly discussed.

  18. Sample preparation with solid phase microextraction and exhaustive extraction approaches: Comparison for challenging cases.

    Science.gov (United States)

    Boyacı, Ezel; Rodríguez-Lafuente, Ángel; Gorynski, Krzysztof; Mirnaghi, Fatemeh; Souza-Silva, Érica A; Hein, Dietmar; Pawliszyn, Janusz

    2015-05-11

    In chemical analysis, sample preparation is frequently considered the bottleneck of the entire analytical method. The success of the final method strongly depends on understanding the entire process of analysis of a particular type of analyte in a sample, namely: the physicochemical properties of the analytes (solubility, volatility, polarity etc.), the environmental conditions, and the matrix components of the sample. Various sample preparation strategies have been developed based on exhaustive or non-exhaustive extraction of analytes from matrices. Undoubtedly, amongst all sample preparation approaches, liquid extraction, including liquid-liquid (LLE) and solid phase extraction (SPE), are the most well-known, widely used, and commonly accepted methods by many international organizations and accredited laboratories. Both methods are well documented and there are many well defined procedures, which make them, at first sight, the methods of choice. However, many challenging tasks, such as complex matrix applications, on-site and in vivo applications, and determination of matrix-bound and free concentrations of analytes, are not easily attainable with these classical approaches for sample preparation. In the last two decades, the introduction of solid phase microextraction (SPME) has brought significant progress in the sample preparation area by facilitating on-site and in vivo applications, time weighted average (TWA) and instantaneous concentration determinations. Recently introduced matrix compatible coatings for SPME facilitate direct extraction from complex matrices and fill the gap in direct sampling from challenging matrices. Following introduction of SPME, numerous other microextraction approaches evolved to address limitations of the above mentioned techniques. There is not a single method that can be considered as a universal solution for sample preparation. This review aims to show the main advantages and limitations of the above mentioned sample

  19. Microfluidic Sample Preparation for Diagnostic Cytopathology

    Science.gov (United States)

    Mach, Albert J.; Adeyiga, Oladunni B.; Di Carlo, Dino

    2014-01-01

    The cellular components of body fluids are routinely analyzed to identify disease and treatment approaches. While significant focus has been placed on developing cell analysis technologies, tools to automate the preparation of cellular specimens have been more limited, especially for body fluids beyond blood. Preparation steps include separating, concentrating, and exposing cells to reagents. Sample preparation continues to be routinely performed off-chip by technicians, preventing cell-based point-of-care diagnostics, increasing the cost of tests, and reducing the consistency of the final analysis following multiple manually-performed steps. Here, we review the assortment of biofluids for which suspended cells are analyzed, along with their characteristics and diagnostic value. We present an overview of the conventional sample preparation processes for cytological diagnosis. We finally discuss the challenges and opportunities in developing microfluidic devices for the purpose of automating or miniaturizing these processes, with particular emphases on preparing large or small volume samples, working with samples of high cellularity, automating multi-step processes, and obtaining high purity subpopulations of cells. We hope to convey the importance of and help identify new research directions addressing the vast biological and clinical applications in preparing and analyzing the array of available biological fluids. Successfully addressing the challenges described in this review can lead to inexpensive systems to improve diagnostic accuracy while simultaneously reducing overall systemic healthcare costs. PMID:23380972

  20. Trichlorosilane and silicon tetrachloride sample preparation for determination of boron, phosphorus and arsenic microelements

    International Nuclear Information System (INIS)

    Stolyarova, I.V.; Orlova, V.A.

    1995-01-01

    The conditions of sample preparation ensuring virtually complete elimination of boron, phosphorus, and arsenic losses are elaborated. Analysis procedures are proposed that involve hydrolysis in an autoclave for exothermic reactions and/or in an open reaction reservoir on frozen twice-distilled water with complexing-agent and oxidant solutionsd applied layer-by-layer, with the possible subsequent atomic-emission, extraction-spectrophotometric, or extraction-colorimetric determination of boron, phosphorus, and arsenic. The procedures improve the accuracy and precision of the results and reduce the duration of chemical preparation due to the quantitative preconcentration of boron, phosphorus, and arsenic; they almost completely eliminate the possibility of the formation of volatile fluoride forms of these elements. 11 refs.; 3 tabs

  1. Sample preparation for the HAW project and experimental results from the HFR

    International Nuclear Information System (INIS)

    Garcia Celma, A.; Wees, H. van; Miralles, L.

    1990-09-01

    This report deals with the preparation and analysis of samples, during the period May 1989-November 1989, for the High-Active Waste (HAW) project, a large-scale in situ test being performed underground in the Asse salt mine, Remlingen FRG. The development of the technical procedures required, and the scientific results, which regard mostly characterization of Potasas del Llobregat sample, are reported. Prior to using the samples in both the H.A.W. and the H.F.R. experiments they have to be machined to fit their holders. Technical improvements for machining samples of salt are reported. (H.W.). 9 refs.; 68 figs.; 10 tabs

  2. Recommended operating procedure number 56: Collection of gaseous grab samples from combustion sources for nitrous oxide measurement. Final report, Jan-Dec 91

    International Nuclear Information System (INIS)

    Ryan, J.V.; Karns, S.A.

    1992-07-01

    The document is a recommended operating procedure (ROP), prepared for use in research activities conducted by EPA's Air and Energy Engineering Research Laboratory (AEERL). The procedure applies to the collection of gaseous grab samples from fossil fuel combustion sources for subsequent analysis of nitrous oxide. The procedure details only the grab sampling methodology and associated equipment

  3. 42 CFR 431.814 - Sampling plan and procedures.

    Science.gov (United States)

    2010-10-01

    ... reliability of the reduced sample. (4) The sample selection procedure. Systematic random sampling is... sampling, and yield estimates with the same or better precision than achieved in systematic random sampling... 42 Public Health 4 2010-10-01 2010-10-01 false Sampling plan and procedures. 431.814 Section 431...

  4. Ergonomic analysis of radiopharmaceuticals samples preparation process

    International Nuclear Information System (INIS)

    Gomes, Luciene Betzler C.; Santos, Isaac Luquetti dos; Fonseca, Antonio Carlos C. da; Pellini, Marcos Pinto; Rebelo, Ana Maria

    2005-01-01

    The doses of radioisotopes to be administrated in patients for diagnostic effect or therapy are prepared in the radiopharmacological sector. The preparation process adopts techniques that are aimed to reduce the exposition time of the professionals and the absorption of excessive doses for patients. The ergonomic analysis of this process contributes in the prevention of occupational illnesses and to prevent risks of accidents during the routines, providing welfare and security to the involved users and conferring to the process an adequate working standard. In this context it is perceived relevance of studies that deal with the analysis of factors that point with respect to the solution of problems and for establishing proposals that minimize risks in the exercise of the activities. Through a methodology that considers the application of the concepts of Ergonomics, it is searched the improvement of the effectiveness or the quality and reduction of the difficulties lived for the workers. The work prescribed, established through norms and procedures codified will be faced with the work effectively carried through, the real work, shaped to break the correct appreciation, with focus in the activities. This work has as objective to argue an ergonomic analysis of samples preparation process of radioisotopes in the Setor de Radiofarmacia do Hospital Universitario Clementino Fraga Filho da Universidade Federal do Rio de Janeiro (UFRJ). (author)

  5. k-Means: Random Sampling Procedure

    Indian Academy of Sciences (India)

    First page Back Continue Last page Overview Graphics. k-Means: Random Sampling Procedure. Optimal 1-Mean is. Approximation of Centroid (Inaba et al). S = random sample of size O(1/ ); Centroid of S is a (1+ )-approx centroid of P with constant probability.

  6. Novel Sample-handling Approach for XRD Analysis with Minimal Sample Preparation

    Science.gov (United States)

    Sarrazin, P.; Chipera, S.; Bish, D.; Blake, D.; Feldman, S.; Vaniman, D.; Bryson, C.

    2004-01-01

    Sample preparation and sample handling are among the most critical operations associated with X-ray diffraction (XRD) analysis. These operations require attention in a laboratory environment, but they become a major constraint in the deployment of XRD instruments for robotic planetary exploration. We are developing a novel sample handling system that dramatically relaxes the constraints on sample preparation by allowing characterization of coarse-grained material that would normally be impossible to analyze with conventional powder-XRD techniques.

  7. Sample preparation: a critical step in the analysis of cholesterol oxidation products.

    Science.gov (United States)

    Georgiou, Christiana A; Constantinou, Michalis S; Kapnissi-Christodoulou, Constantina P

    2014-02-15

    In recent years, cholesterol oxidation products (COPs) have drawn scientific interest, particularly due to their implications on human health. A big number of these compounds have been demonstrated to be cytotoxic, mutagenic, and carcinogenic. The main source of COPs is through diet, and particularly from the consumption of cholesterol-rich foods. This raises questions about the safety of consumers, and it suggests the necessity for the development of a sensitive and a reliable analytical method in order to identify and quantify these components in food samples. Sample preparation is a necessary step in the analysis of COPs in order to eliminate interferences and increase sensitivity. Numerous publications have, over the years, reported the use of different methods for the extraction and purification of COPs. However, no method has, so far, been established as a routine method for the analysis of COPs in foods. Therefore, it was considered important to overview different sample preparation procedures and evaluate the different preparative parameters, such as time of saponification, the type of organic solvents for fat extraction, the stationary phase in solid phase extraction, etc., according to recovery, precision and simplicity. Copyright © 2013 Elsevier Ltd. All rights reserved.

  8. Operability test procedure for PFP wastewater sampling facility

    International Nuclear Information System (INIS)

    Hirzel, D.R.

    1995-01-01

    Document provides instructions for performing the Operability Test of the 225-WC Wastewater Sampling Station which monitors the discharge to the Treated Effluent Disposal Facility from the Plutonium Finishing Plant. This Operability Test Procedure (OTP) has been prepared to verify correct configuration and performance of the PFP Wastewater sampling system installed in Building 225-WC located outside the perimeter fence southeast of the Plutonium Finishing Plant (PFP). The objective of this test is to ensure the equipment in the sampling facility operates in a safe and reliable manner. The sampler consists of two Manning Model S-5000 units which are rate controlled by the Milltronics Ultrasonic flowmeter at manhole No.C4 and from a pH measuring system with the sensor in the stream adjacent to the sample point. The intent of the dual sampling system is to utilize one unit to sample continuously at a rate proportional to the wastewater flow rate so that the aggregate tests are related to the overall flow and thereby eliminate isolated analyses. The second unit will only operate during a high or low pH excursion of the stream (hence the need for a pH control). The major items in this OTP include testing of the Manning Sampler System and associated equipment including the pH measuring and control system, the conductivity monitor, and the flow meter

  9. Field sampling, preparation procedure and plutonium analyses of large freshwater samples

    International Nuclear Information System (INIS)

    Straelberg, E.; Bjerk, T.O.; Oestmo, K.; Brittain, J.E.

    2002-01-01

    This work is part of an investigation of the mobility of plutonium in freshwater systems containing humic substances. A well-defined bog-stream system located in the catchment area of a subalpine lake, Oevre Heimdalsvatn, Norway, is being studied. During the summer of 1999, six water samples were collected from the tributary stream Lektorbekken and the lake itself. However, the analyses showed that the plutonium concentration was below the detection limit in all the samples. Therefore renewed sampling at the same sites was carried out in August 2000. The results so far are in agreement with previous analyses from the Heimdalen area. However, 100 times higher concentrations are found in the lowlands in the eastern part of Norway. The reason for this is not understood, but may be caused by differences in the concentrations of humic substances and/or the fact that the mountain areas are covered with snow for a longer period of time every year. (LN)

  10. "On-off" switchable tool for food sample preparation: merging molecularly imprinting technology with stimuli-responsive blocks. Current status, challenges and highlighted applications.

    Science.gov (United States)

    Garcia, Raquel; Gomes da Silva, Marco D R; Cabrita, Maria João

    2018-01-01

    Sample preparation still remains a great challenge in the analytical workflow representing the most time-consuming and laborious step in analytical procedures. Ideally, sample pre-treatment procedures must be more selective, cheap, quick and environmental friendly. Molecular imprinting technology is a powerful tool in the development of highly selective sample preparation methodologies enabling to preconcentrate the analytes from a complex food matrix. Actually, the design and development of molecularly imprinted polymers-based functional materials that merge an enhancement of selectivity with a controllable and switchable mode of action by means of specific stimulus constitutes a hot research topic in the field of food analysis. Thus, combining the stimuli responsive mechanism and imprinting technology a new generation of materials are emerging. The application of these smart materials in sample preparation is in early stage of development, nevertheless new improvements will promote a new driven in the demanding field of food sample preparation. The new trends in the advancement of food sample preparation using these smart materials will be presented in this review and highlighted the most relevant applications in this particular area of knowledge. Copyright © 2017 Elsevier B.V. All rights reserved.

  11. States and state-preparing procedures in quantum mechanics

    International Nuclear Information System (INIS)

    Benioff, P.A.; Ekstein, Hans

    D'Espagnat and others have shown that different preparation procedures that mix systems prepared in unequivalent states and objectively different, are nevertheless assigned the same state. This unpalatable result follows from the usual interpretative rules of quantum mechanics. It is shown here that this result is incompatible with the strengthened interpretative rules (requiring randomness of the measurement outcome sequence) recently proposed. Thus, the randomness requirement restores reasonableness

  12. Rapid filtration separation-based sample preparation method for Bacillus spores in powdery and environmental matrices.

    Science.gov (United States)

    Isabel, Sandra; Boissinot, Maurice; Charlebois, Isabelle; Fauvel, Chantal M; Shi, Lu-E; Lévesque, Julie-Christine; Paquin, Amélie T; Bastien, Martine; Stewart, Gale; Leblanc, Eric; Sato, Sachiko; Bergeron, Michel G

    2012-03-01

    Authorities frequently need to analyze suspicious powders and other samples for biothreat agents in order to assess environmental safety. Numerous nucleic acid detection technologies have been developed to detect and identify biowarfare agents in a timely fashion. The extraction of microbial nucleic acids from a wide variety of powdery and environmental samples to obtain a quality level adequate for these technologies still remains a technical challenge. We aimed to develop a rapid and versatile method of separating bacteria from these samples and then extracting their microbial DNA. Bacillus atrophaeus subsp. globigii was used as a simulant of Bacillus anthracis. We studied the effects of a broad variety of powdery and environmental samples on PCR detection and the steps required to alleviate their interference. With a benchmark DNA extraction procedure, 17 of the 23 samples investigated interfered with bacterial lysis and/or PCR-based detection. Therefore, we developed the dual-filter method for applied recovery of microbial particles from environmental and powdery samples (DARE). The DARE procedure allows the separation of bacteria from contaminating matrices that interfere with PCR detection. This procedure required only 2 min, while the DNA extraction process lasted 7 min, for a total of sample preparation procedure allowed the recovery of cleaned bacterial spores and relieved detection interference caused by a wide variety of samples. Our procedure was easily completed in a laboratory facility and is amenable to field application and automation.

  13. A procedure for preparing alkali metal hydrides

    International Nuclear Information System (INIS)

    Lemieux, R.U.; Sanford, C.E.; Prescott, J.F.

    1976-01-01

    A plain low cost, procedure for the continuous, low temperature preparation of sodium or potassium hydrides using cheap reagents is presented. Said invention is especially concerned with a process of purifying of a catalytic exchange liquid used for deuterium enrichment, in which an alkali metal hydride is produced as intermediate product. The procedure for producing the sodium and potassium hydrides consists in causing high pressure hydrogen to be absorbed by a mixture of at least a lower monoalkylamine and an alkylamide of an alkali metal from at least one of said amines [fr

  14. Collection and preparation of bottom sediment samples for analysis of radionuclides and trace elements

    International Nuclear Information System (INIS)

    2003-07-01

    The publication is the first in a series of TECDOCs on sampling and sample handling as part of the IAEA support to improve reliability of nuclear analytical techniques (NATs) in Member State laboratories. The purpose of the document is to provide information on the methods for collecting sediments, the equipment used, and the sample preparation techniques for radionuclide and elemental analysis. The most appropriate procedures for defining the strategies and criteria for selecting sampling locations, for sample storage and transportation are also given. Elements of QA/QC and documentation needs for sampling and sediment analysis are discussed. Collection and preparation of stream and river bottom sediments, lake bottom sediments, estuary bottom sediments, and marine (shallow) bottom sediments are covered. The document is intended to be a comprehensive manual for the collection and preparation of bottom sediments as a prerequisite to obtain representative and meaningful results using NATs. Quality assurance and quality control (QA/QC) is emphasized as an important aspect to ensure proper collection, transportation, preservation, and analysis since it forms the basis for interpretation and legislation. Although there are many approaches and methods available for sediment analyses, the scope of the report is limited to sample preparation for (1) analysis of radionuclides (including sediment dating using radionuclides such as Pb-210 and Cs-137) and (2) analysis of trace, minor and major elements using nuclear and related analytical techniques such as NAA, XRF and PIXE

  15. Collection and preparation of bottom sediment samples for analysis of radionuclides and trace elements

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2003-07-01

    The publication is the first in a series of TECDOCs on sampling and sample handling as part of the IAEA support to improve reliability of nuclear analytical techniques (NATs) in Member State laboratories. The purpose of the document is to provide information on the methods for collecting sediments, the equipment used, and the sample preparation techniques for radionuclide and elemental analysis. The most appropriate procedures for defining the strategies and criteria for selecting sampling locations, for sample storage and transportation are also given. Elements of QA/QC and documentation needs for sampling and sediment analysis are discussed. Collection and preparation of stream and river bottom sediments, lake bottom sediments, estuary bottom sediments, and marine (shallow) bottom sediments are covered. The document is intended to be a comprehensive manual for the collection and preparation of bottom sediments as a prerequisite to obtain representative and meaningful results using NATs. Quality assurance and quality control (QA/QC) is emphasized as an important aspect to ensure proper collection, transportation, preservation, and analysis since it forms the basis for interpretation and legislation. Although there are many approaches and methods available for sediment analyses, the scope of the report is limited to sample preparation for (1) analysis of radionuclides (including sediment dating using radionuclides such as Pb-210 and Cs-137) and (2) analysis of trace, minor and major elements using nuclear and related analytical techniques such as NAA, XRF and PIXE.

  16. Sample preparation of environmental samples using benzene synthesis followed by high-performance LSC

    International Nuclear Information System (INIS)

    Filippis, S. De; Noakes, J.E.

    1991-01-01

    Liquid scintillation counting (LSC) techniques have been widely employed as the detection method for determining environmental levels of tritium and 14 C. Since anthropogenic and nonanthropogenic inputs to the environment are a concern, sampling the environment surrounding a nuclear power facility or fuel reprocessing operation requires the collection of many different sample types, including agriculture products, water, biota, aquatic life, soil, and vegetation. These sample types are not suitable for the direct detection of tritium of 14 C for liquid scintillation techniques. Each sample type must be initially prepared in order to obtain the carbon or hydrogen component of interest and present this in a chemical form that is compatible with common chemicals used in scintillation counting applications. Converting the sample of interest to chemically pure benzene as a sample preparation technique has been widely accepted for processing samples for radiocarbon age-dating applications. The synthesized benzene is composed of the carbon or hydrogen atoms from the original sample and is ideal as a solvent for LSC with excellent photo-optical properties. Benzene synthesis followed by low-background scintillation counting can be applied to the preparation and measurement of environmental samples yielding good detection sensitivities, high radionuclide counting efficiency, and shorter preparation time. The method of benzene synthesis provides a unique approach to the preparation of a wide variety of environmental sample types using similar chemistry for all samples

  17. Procedure for the preparation of tritium-labelled insulins

    International Nuclear Information System (INIS)

    Bienert, M.; Haensicke, A.; Beyermann, M.; Kaufmann, K.D.; Oehlke, J.; Klauschenz, E.; Bespalowa, S.; Titov, M.; Pleiss, U.

    1986-01-01

    This invention is concerned with a procedure for the preparation of specific 3 H-labelled insulins with sequences of human, bovine or porcine insulins and without simultaneous chemical modifications of the insulin. On the basis of this procedure a 3 H 2 -Typ (B26)-insulin can be obtained in good yield and purity with a specific radioactivity appropriate to biopharmaceutical and pharmacokinetic purposes in medicine and pharmaceutical industry, resp

  18. Quantitative sample preparation of some heavy elements

    International Nuclear Information System (INIS)

    Jaffey, A.H.

    1977-01-01

    A discussion is given of some techniques that have been useful in quantitatively preparing and analyzing samples used in the half-life determinations of some plutonium and uranium isotopes. Application of these methods to the preparation of uranium and plutonium samples used in neutron experiments is discussed

  19. Preparation Of Deposited Sediment Sample By Casting Method For Environmental Study

    International Nuclear Information System (INIS)

    Hutabarat, Tommy; Ristin PI, Evarista

    2000-01-01

    The preparation of deposited sediment sample by c asting m ethod for environmental study has been carried out. This method comprises separation of size fraction and casting process. The deposited sediment samples were wet sieved to separate the size fraction of >500 mum, (250-500) mum, (125-250) mum and (63-125) mum and settling procedures were followed for the separation of (40-63) mum, (20-40) mum, (10-20) mum and o C, ashed at 450 o C, respectively. In the casting process of sample, it was used polyester rapid cure resin and methyl ethyl ketone peroxide (MEKP) hardener. The moulded sediment sample was poured onto caster, allow for 60 hours long. The aim of this method is to get the casted sample which can be used effectively, efficiently and to be avoided from contamination of each other samples. Before casting, samples were grinded up to be fine. The result shows that casting product is ready to be used for natural radionuclide analysis

  20. 7 CFR 27.21 - Preparation of samples of cotton.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 2 2010-01-01 2010-01-01 false Preparation of samples of cotton. 27.21 Section 27.21... REGULATIONS COTTON CLASSIFICATION UNDER COTTON FUTURES LEGISLATION Regulations Inspection and Samples § 27.21 Preparation of samples of cotton. The samples from each bale shall be prepared as specified in this section...

  1. Establishing a routine procedure for extraction of water from vegetation samples

    International Nuclear Information System (INIS)

    Varlam, Carmen; Stefanescu, Ioan; Faurescu, Ionut; Vagner, Irina; Faurescu, Denisa

    2008-01-01

    Full text: The Cryogenic Pilot is an experimental project within the nuclear energy national research program, which has the aim of developing technologies for tritium and deuterium separation by cryogenic distillation. The process, used in this installation, is based on a combined method for liquid-phase catalytic exchange (LPCE) and cryogenic distillation. There are two ways that Cryogenic Pilot can interact with the environment: by atmospheric release and by sewage. In order to establish the base line of tritium concentration in the environment around the nuclear facilities we investigated the preparation procedure for different type of samples: soil, hay, apple, grass, milk, meat and water. For azeotropic distillation of all types of samples two solvents were used, toluene and cyclohexane, and all measurements for determination of environmental tritium concentration were carry out using liquid scintillation counting (LSC), with ultra-low level liquid scintillation spectrometer Quantulus 1220 specially designed for environmental samples and low radioactivity. Sample scintillation cocktail ratio was 8:12 ml and liquid scintillation cocktail was UltimaGold LLT. The background determined for control samples prepared ranged between 0.926 Cpm and 1.002 Cpm and counting efficiency between 25.3% and 26.1%. The counting time was 1000 minutes (50 minutes/20 cycles) for each sample, and minimum detectable activity according to ISO 9698 was 8.9 TU, and 9.05 TU, respectively, with a confidence coefficient of 3. (authors)

  2. Preparation and calibration by liquid scintillation of a sample of Cl 36

    International Nuclear Information System (INIS)

    Grau Malonda, A.; Los Arcos, J.M.; Rodriguez Barquero, L.; Suarez, C.

    1989-01-01

    A procedure to prepare a sample of Clorine 36, as Li 36 Cl, able to be measured by liquid scintillation counting, is described. The sample is chemically stable, with no variation of the quenching parameter up to 4 mg of LiCl per 15 ml of scintillator, keeps constant the counting efficiency for concentration higher than 40 μg of Li 36 Cl in that volume, and shows no deterioration over a 3 weed period. The Li 36 Cl solution has been standarized using the free parameter method with different volumes of toluene, PCS and Instagel, to an uncertainty of 0,3% (Author)

  3. Urine sample preparation for proteomic analysis.

    Science.gov (United States)

    Olszowy, Pawel; Buszewski, Boguslaw

    2014-10-01

    Sample preparation for both environmental and more importantly biological matrices is a bottleneck of all kinds of analytical processes. In the case of proteomic analysis this element is even more important due to the amount of cross-reactions that should be taken into consideration. The incorporation of new post-translational modifications, protein hydrolysis, or even its degradation is possible as side effects of proteins sample processing. If protocols are evaluated appropriately, then identification of such proteins does not bring difficulties. However, if structural changes are provided without sufficient attention then protein sequence coverage will be reduced or even identification of such proteins could be impossible. This review summarizes obstacles and achievements in protein sample preparation of urine for proteome analysis using different tools for mass spectrometry analysis. The main aim is to present comprehensively the idea of urine application as a valuable matrix. This article is dedicated to sample preparation and application of urine mainly in novel cancer biomarkers discovery. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  4. Soil Gas Sampling Operating Procedure

    Science.gov (United States)

    EPA Region 4 Science and Ecosystem Support Division (SESD) document that describes general and specific procedures, methods, and considerations when collecting soil gas samples for field screening or laboratory analysis.

  5. The effects of preparation, shipment and ageing on the Pu elemental assay results of milligram-sized samples

    International Nuclear Information System (INIS)

    Berger, J.; Doubek, N.; Jammet, G.; Aigner, H.; Bagliano, G.; Donohue, D.; Kuhn, E.

    1994-02-01

    Specialized procedures have been implemented for the sampling of Pu-containing materials such as Pu nitrate, oxide or mixed oxide in States which have not yet approved type B(U) shipment containers for the air-shipment of gram-sized quantities of Pu. In such cases, it it necessary to prepare samples for shipment which contain only milligram quantities of Pu dried from solution in penicillin vials. Potential problems due to flaking-off during shipment could affect the recovery of Pu at the analytical laboratory. Therefore, a series of tests was performed with synthetic Pu nitrated, and mixed U, Pu nitrated samples to test the effectiveness of the evaporation and recovery procedures. Results of these tests as well as experience with actual inspection samples are presented, showing conclusively that the existing procedures are satisfactory. (author). 11 refs, 6 figs, 8 tabs

  6. Recent advances in applications of nanomaterials for sample preparation.

    Science.gov (United States)

    Xu, Linnan; Qi, Xiaoyue; Li, Xianjiang; Bai, Yu; Liu, Huwei

    2016-01-01

    Sample preparation is a key step for qualitative and quantitative analysis of trace analytes in complicated matrix. Along with the rapid development of nanotechnology in material science, numerous nanomaterials have been developed with particularly useful applications in analytical chemistry. Benefitting from their high specific areas, increased surface activities, and unprecedented physical/chemical properties, the potentials of nanomaterials for rapid and efficient sample preparation have been exploited extensively. In this review, recent progress of novel nanomaterials applied in sample preparation has been summarized and discussed. Both nanoparticles and nanoporous materials are evaluated for their unusual performance in sample preparation. Various compositions and functionalizations extended the applications of nanomaterials in sample preparations, and distinct size and shape selectivity was generated from the diversified pore structures of nanoporous materials. Such great variety make nanomaterials a kind of versatile tools in sample preparation for almost all categories of analytes. Copyright © 2015 Elsevier B.V. All rights reserved.

  7. Liquid scintillation: Sample preparation and counting atypical emissions

    International Nuclear Information System (INIS)

    Anon.

    1991-01-01

    Liquid scintillation sample preparation has the most published information but the least amount of definitive technical direction because the chemical and physical nature of the samples from biological investigations varies widely. This chapter discusses the following related topics: Aqueous Samples; Tissue Solubilizers; Absorption of 14 CO 2 ; Sample Combustion Methods; Heterogeneous Systems; Sample Preparation Problems (colored samples, chemiluminescence, photoluminescence, static electricity); Counting Various Types of Emitters; Counting Atypical Emissions. 2 refs., 2 figs

  8. Microfluidic devices for sample preparation and rapid detection of foodborne pathogens.

    Science.gov (United States)

    Kant, Krishna; Shahbazi, Mohammad-Ali; Dave, Vivek Priy; Ngo, Tien Anh; Chidambara, Vinayaka Aaydha; Than, Linh Quyen; Bang, Dang Duong; Wolff, Anders

    2018-03-10

    Rapid detection of foodborne pathogens at an early stage is imperative for preventing the outbreak of foodborne diseases, known as serious threats to human health. Conventional bacterial culturing methods for foodborne pathogen detection are time consuming, laborious, and with poor pathogen diagnosis competences. This has prompted researchers to call the current status of detection approaches into question and leverage new technologies for superior pathogen sensing outcomes. Novel strategies mainly rely on incorporating all the steps from sample preparation to detection in miniaturized devices for online monitoring of pathogens with high accuracy and sensitivity in a time-saving and cost effective manner. Lab on chip is a blooming area in diagnosis, which exploits different mechanical and biological techniques to detect very low concentrations of pathogens in food samples. This is achieved through streamlining the sample handling and concentrating procedures, which will subsequently reduce human errors and enhance the accuracy of the sensing methods. Integration of sample preparation techniques into these devices can effectively minimize the impact of complex food matrix on pathogen diagnosis and improve the limit of detections. Integration of pathogen capturing bio-receptors on microfluidic devices is a crucial step, which can facilitate recognition abilities in harsh chemical and physical conditions, offering a great commercial benefit to the food-manufacturing sector. This article reviews recent advances in current state-of-the-art of sample preparation and concentration from food matrices with focus on bacterial capturing methods and sensing technologies, along with their advantages and limitations when integrated into microfluidic devices for online rapid detection of pathogens in foods and food production line. Copyright © 2018. Published by Elsevier Inc.

  9. Automated sample preparation station for studying self-diffusion in porous solids with NMR spectroscopy

    Science.gov (United States)

    Hedin, Niklas; DeMartin, Gregory J.; Reyes, Sebastián C.

    2006-03-01

    In studies of gas diffusion in porous solids with nuclear magnetic resonance (NMR) spectroscopy the sample preparation procedure becomes very important. An apparatus is presented here that pretreats the sample ex situ and accurately sets the desired pressure and temperature within the NMR tube prior to its introduction in the spectrometer. The gas manifold that supplies the NMR tube is also connected to a microbalance containing another portion of the same sample, which is kept at the same temperature as the sample in the NMR tube. This arrangement permits the simultaneous measurement of the adsorption loading on the sample, which is required for the interpretation of the NMR diffusion experiments. Furthermore, to ensure a good seal of the NMR tube, a hybrid valve design composed of titanium, a Teflon® seat, and Kalrez® O-rings is utilized. A computer controlled algorithm ensures the accuracy and reproducibility of all the procedures, enabling the NMR diffusion experiments to be performed at well controlled conditions of pressure, temperature, and amount of gas adsorbed on the porous sample.

  10. Recent advances in column switching sample preparation in bioanalysis.

    Science.gov (United States)

    Kataoka, Hiroyuki; Saito, Keita

    2012-04-01

    Column switching techniques, using two or more stationary phase columns, are useful for trace enrichment and online automated sample preparation. Target fractions from the first column are transferred online to a second column with different properties for further separation. Column switching techniques can be used to determine the analytes in a complex matrix by direct sample injection or by simple sample treatment. Online column switching sample preparation is usually performed in combination with HPLC or capillary electrophoresis. SPE or turbulent flow chromatography using a cartridge column and in-tube solid-phase microextraction using a capillary column have been developed for convenient column switching sample preparation. Furthermore, various micro-/nano-sample preparation devices using new polymer-coating materials have been developed to improve extraction efficiency. This review describes current developments and future trends in novel column switching sample preparation in bioanalysis, focusing on innovative column switching techniques using new extraction devices and materials.

  11. Comparison of transition-matrix sampling procedures

    DEFF Research Database (Denmark)

    Yevick, D.; Reimer, M.; Tromborg, Bjarne

    2009-01-01

    We compare the accuracy of the multicanonical procedure with that of transition-matrix models of static and dynamic communication system properties incorporating different acceptance rules. We find that for appropriate ranges of the underlying numerical parameters, algorithmically simple yet high...... accurate procedures can be employed in place of the standard multicanonical sampling algorithm....

  12. Recent advances in metal-organic frameworks and covalent organic frameworks for sample preparation and chromatographic analysis.

    Science.gov (United States)

    Wang, Xuan; Ye, Nengsheng

    2017-12-01

    In the field of analytical chemistry, sample preparation and chromatographic separation are two core procedures. The means by which to improve the sensitivity, selectivity and detection limit of a method have become a topic of great interest. Recently, porous organic frameworks, such as metal-organic frameworks (MOFs) and covalent organic frameworks (COFs), have been widely used in this research area because of their special features, and different methods have been developed. This review summarizes the applications of MOFs and COFs in sample preparation and chromatographic stationary phases. The MOF- or COF-based solid-phase extraction (SPE), solid-phase microextraction (SPME), gas chromatography (GC), high-performance liquid chromatography (HPLC) and capillary electrochromatography (CEC) methods are described. The excellent properties of MOFs and COFs have resulted in intense interest in exploring their performance and mechanisms for sample preparation and chromatographic separation. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Modular microfluidic system for biological sample preparation

    Science.gov (United States)

    Rose, Klint A.; Mariella, Jr., Raymond P.; Bailey, Christopher G.; Ness, Kevin Dean

    2015-09-29

    A reconfigurable modular microfluidic system for preparation of a biological sample including a series of reconfigurable modules for automated sample preparation adapted to selectively include a) a microfluidic acoustic focusing filter module, b) a dielectrophoresis bacteria filter module, c) a dielectrophoresis virus filter module, d) an isotachophoresis nucleic acid filter module, e) a lyses module, and f) an isotachophoresis-based nucleic acid filter.

  14. Applications of Liquid-Phase Microextraction in the Sample Preparation of Environmental Solid Samples

    Directory of Open Access Journals (Sweden)

    Helena Prosen

    2014-05-01

    Full Text Available Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environmental solid samples (soil, sediments, sewage sludge, dust etc. published in the last decade. Several innovative liquid-phase microextraction (LPME techniques that have emerged recently have also been applied as an aid in sample preparation of these samples: single-drop microextraction (SDME, hollow fiber-liquid phase microextraction (HF-LPME, dispersive liquid-liquid microextraction (DLLME. Besides the common organic solvents, surfactants and ionic liquids are also used. However, these techniques have to be combined with another technique to release the analytes from the solid sample into an aqueous solution. In the present review, the published methods were categorized into three groups: LPME in combination with a conventional solvent extraction; LPME in combination with an environmentally friendly extraction; LPME without previous extraction. The applicability of these approaches to the sample preparation for the determination of pollutants in solid environmental samples is discussed, with emphasis on their strengths, weak points and environmental impact.

  15. Applications of liquid-phase microextraction in the sample preparation of environmental solid samples.

    Science.gov (United States)

    Prosen, Helena

    2014-05-23

    Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environmental solid samples (soil, sediments, sewage sludge, dust etc.) published in the last decade. Several innovative liquid-phase microextraction (LPME) techniques that have emerged recently have also been applied as an aid in sample preparation of these samples: single-drop microextraction (SDME), hollow fiber-liquid phase microextraction (HF-LPME), dispersive liquid-liquid microextraction (DLLME). Besides the common organic solvents, surfactants and ionic liquids are also used. However, these techniques have to be combined with another technique to release the analytes from the solid sample into an aqueous solution. In the present review, the published methods were categorized into three groups: LPME in combination with a conventional solvent extraction; LPME in combination with an environmentally friendly extraction; LPME without previous extraction. The applicability of these approaches to the sample preparation for the determination of pollutants in solid environmental samples is discussed, with emphasis on their strengths, weak points and environmental impact.

  16. Indigenous development of automated metallographic sample preparation system

    International Nuclear Information System (INIS)

    Kulkarni, A.P.; Pandit, K.M.; Deshmukh, A.G.; Sahoo, K.C.

    2005-01-01

    Surface preparation of specimens for Metallographic studies on irradiated material involves a lot of remote handling of radioactive material by skilled manpower. These are laborious and man-rem intensive activities and put limitations on number of samples that can be prepared for the metallographic studies. To overcome these limitations, automated systems have been developed for surface preparation of specimens in PIE division. The system includes (i) Grinding and polishing stations (ii) Water jet cleaning station (iii) Ultrasonic cleaning stations (iv) Drying station (v) Sample loading and unloading station (vi) Dispenser for slurries and diluents and (vii) Automated head for movement of the sample holder disc from one station to other. System facilities the operator for programming/changing sequence of the sample preparations including remote changing of grinding/polishing discs from the stations. Two such systems have been installed and commissioned in Hot Cell for PIE Division. These are being used for preparation of irradiated samples from nuclear fuels and structural components. This development has increased the throughput of metallography work and savings in terms of (man-severts) radiation exposure to operators. This presentation will provide details of the challenges in undertaking this developmental work. (author)

  17. Development of a simple extraction procedure for chlorpyrifos determination in food samples by immunoassay.

    Science.gov (United States)

    Gabaldón, J A; Maquieira, A; Puchades, R

    2007-02-28

    The suitability of immunoassay methodology for rapid and accurate determination of chlorpyrifos in vegetables was tested. The optimised ELISA detection limit was 0.32ng/ml, with a working range from 0.69 to 6.21ng/ml and an immunoassay test-mid point (IC(50)) of 2.08ng/ml. A rapid sample preparation procedure considering different parameters such as the amount of sample, volume of extractant, extraction time and dilution factor was optimised. The developed direct extraction (DE) and multiresidue (ME) standard procedures were performed in different fortified fresh and processed vegetable samples (tomato, bonnet pepper, bean, pea, asparagus, broccoli, watermelon, melon, lettuce, cucumber, celery and red pepper). Recoveries were in all cases in the whole range 85.2-108.9% for both DE and ME extracts. Also, the comparison of the results obtained by both immunochemical and chromatographic methods for spiked fruits and vegetables were good with a correlation coefficient (r) of 0.97.

  18. Simple and Reproducible Sample Preparation for Single-Shot Phosphoproteomics with High Sensitivity

    DEFF Research Database (Denmark)

    Jersie-Christensen, Rosa R.; Sultan, Abida; Olsen, Jesper V

    2016-01-01

    The traditional sample preparation workflow for mass spectrometry (MS)-based phosphoproteomics is time consuming and usually requires multiple steps, e.g., lysis, protein precipitation, reduction, alkylation, digestion, fractionation, and phosphopeptide enrichment. Each step can introduce chemical...... artifacts, in vitro protein and peptide modifications, and contaminations. Those often result in sample loss and affect the sensitivity, dynamic range and accuracy of the mass spectrometric analysis. Here we describe a simple and reproducible phosphoproteomics protocol, where lysis, denaturation, reduction......, and alkylation are performed in a single step, thus reducing sample loss and increasing reproducibility. Moreover, unlike standard cell lysis procedures the cell harvesting is performed at high temperatures (99 °C) and without detergents and subsequent need for protein precipitation. Phosphopeptides are enriched...

  19. HPLC/DAD determination of rosmarinic acid in Salvia officinalis: sample preparation optimization by factorial design

    Energy Technology Data Exchange (ETDEWEB)

    Oliveira, Karina B. de [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Farmacia; Oliveira, Bras H. de, E-mail: bho@ufpr.br [Universidade Federal do Parana (UFPR), Curitiba, PR (Brazil). Dept. de Quimica

    2013-01-15

    Sage (Salvia officinalis) contains high amounts of the biologically active rosmarinic acid (RA) and other polyphenolic compounds. RA is easily oxidized, and may undergo degradation during sample preparation for analysis. The objective of this work was to develop and validate an analytical procedure for determination of RA in sage, using factorial design of experiments for optimizing sample preparation. The statistically significant variables for improving RA extraction yield were determined initially and then used in the optimization step, using central composite design (CCD). The analytical method was then fully validated, and used for the analysis of commercial samples of sage. The optimized procedure involved extraction with aqueous methanol (40%) containing an antioxidant mixture (ascorbic acid and ethylenediaminetetraacetic acid (EDTA)), with sonication at 45 deg C for 20 min. The samples were then injected in a system containing a C{sub 18} column, using methanol (A) and 0.1% phosphoric acid in water (B) in step gradient mode (45A:55B, 0-5 min; 80A:20B, 5-10 min) with flow rate of 1.0 mL min-1 and detection at 330 nm. Using this conditions, RA concentrations were 50% higher when compared to extractions without antioxidants (98.94 {+-} 1.07% recovery). Auto-oxidation of RA during sample extraction was prevented by the use of antioxidants resulting in more reliable analytical results. The method was then used for the analysis of commercial samples of sage. (author)

  20. HPLC/DAD determination of rosmarinic acid in Salvia officinalis: sample preparation optimization by factorial design

    International Nuclear Information System (INIS)

    Oliveira, Karina B. de; Oliveira, Bras H. de

    2013-01-01

    Sage (Salvia officinalis) contains high amounts of the biologically active rosmarinic acid (RA) and other polyphenolic compounds. RA is easily oxidized, and may undergo degradation during sample preparation for analysis. The objective of this work was to develop and validate an analytical procedure for determination of RA in sage, using factorial design of experiments for optimizing sample preparation. The statistically significant variables for improving RA extraction yield were determined initially and then used in the optimization step, using central composite design (CCD). The analytical method was then fully validated, and used for the analysis of commercial samples of sage. The optimized procedure involved extraction with aqueous methanol (40%) containing an antioxidant mixture (ascorbic acid and ethylenediaminetetraacetic acid (EDTA)), with sonication at 45 deg C for 20 min. The samples were then injected in a system containing a C 18 column, using methanol (A) and 0.1% phosphoric acid in water (B) in step gradient mode (45A:55B, 0-5 min; 80A:20B, 5-10 min) with flow rate of 1.0 mL min−1 and detection at 330 nm. Using this conditions, RA concentrations were 50% higher when compared to extractions without antioxidants (98.94 ± 1.07% recovery). Auto-oxidation of RA during sample extraction was prevented by the use of antioxidants resulting in more reliable analytical results. The method was then used for the analysis of commercial samples of sage. (author)

  1. Applications of Liquid-Phase Microextraction in the Sample Preparation of Environmental Solid Samples

    OpenAIRE

    Helena Prosen

    2014-01-01

    Solvent extraction remains one of the fundamental sample preparation techniques in the analysis of environmental solid samples, but organic solvents are toxic and environmentally harmful, therefore one of the possible greening directions is its miniaturization. The present review covers the relevant research from the field of application of microextraction to the sample preparation of environmental solid samples (soil, sediments, sewage sludge, dust etc.) published in the last decade. Several...

  2. Preparation and procedures of pre-commissioning on DECY-13 cyclotron

    International Nuclear Information System (INIS)

    Silakhuddin

    2016-01-01

    A preparation and procedures for pre-commissioning of DECY-13 Cyclotron have been discussed and the steps for these have been arranged. Pre-commissioning is a testing stage of individual subsystems when all subsystems have been integrated into a cyclotron system. The discussion was taken from references, the next the readiness of devices was studied and then the preparation and procedures of the pre-commissioning were arranged. The results of the discussion are that for doing the pre-commissioning of the cyclotron DECY-13 still requires the completion of RF-dee subsystem and some components for testing are still to be completed. (author)

  3. New materials for sample preparation techniques in bioanalysis.

    Science.gov (United States)

    Nazario, Carlos Eduardo Domingues; Fumes, Bruno Henrique; da Silva, Meire Ribeiro; Lanças, Fernando Mauro

    2017-02-01

    The analysis of biological samples is a complex and difficult task owing to two basic and complementary issues: the high complexity of most biological matrices and the need to determine minute quantities of active substances and contaminants in such complex sample. To succeed in this endeavor samples are usually subject to three steps of a comprehensive analytical methodological approach: sample preparation, analytes isolation (usually utilizing a chromatographic technique) and qualitative/quantitative analysis (usually with the aid of mass spectrometric tools). Owing to the complex nature of bio-samples, and the very low concentration of the target analytes to be determined, selective sample preparation techniques is mandatory in order to overcome the difficulties imposed by these two constraints. During the last decade new chemical synthesis approaches has been developed and optimized, such as sol-gel and molecularly imprinting technologies, allowing the preparation of novel materials for sample preparation including graphene and derivatives, magnetic materials, ionic liquids, molecularly imprinted polymers, and much more. In this contribution we will review these novel techniques and materials, as well as their application to the bioanalysis niche. Copyright © 2016 Elsevier B.V. All rights reserved.

  4. Preparation and characterisation of magnetic nanostructured samples for inelastic neutron scattering experiments

    Energy Technology Data Exchange (ETDEWEB)

    Kreuzpaintner, Wolfgang

    2010-06-22

    Recent advances in thin-film structuring techniques have generated significant interest in the dynamics of spin waves in magnetic nanostructures and the possible use of inelastic neutron scattering (INS) for their investigation. This thesis describes the design and implementation, at GKSS Research Centre, of equipment for preparation of large and laterally submicron and nanometre structured magnetic samples for such future INS experiments. After a brief resume on spin waves in nanostructures, the development work on new purpose-designed equipment, including high vacuum (HV) argon ion beam milling and ultra high vacuum (UHV) e-beam evaporation setups, is described. Ni nanodot as well as Ni and novel Gd nanowire samples were prepared using combinations of sputter deposition, laser interference lithography, argon ion beam milling, e-beam evaporation and self organisation techniques. With reference to sample preparation, epitaxial growth studies for Ni on Si(100) substrate were performed, resulting in the development of a new deposition process, which by thermal tuning allows for the direct epitaxial growth of Ni on Si with unprecedented crystalline quality. The results of various characterisation experiments on the prepared nanostructured samples, including Scanning Electron Microscopy (SEM), microprobe analysis, Atomic and Magnetic Force Microscopy (AFM/MFM), Vibrating Sample Magnetometry (VSM), X-ray Diffraction (XRD) and Reflectivity (XRR), unpolarised and Polarised Neutron Scattering (PNR) and off-specular scattering by X-rays and neutrons using rocking scans and Time-Of-Flight Grazing Incidence Small Angle Neutron Scattering (TOF-GISANS), together with various analysis procedures such as Distorted-Wave Born Approximation (DWBA), are reported. The analysis of a Gd nanowire sample by TOF-GISANS led to a novel evaluation technique which in comparison with single wavelength methods allows portions of reciprocal space to be scanned without changing the angle of

  5. Preparation and characterisation of magnetic nanostructured samples for inelastic neutron scattering experiments

    International Nuclear Information System (INIS)

    Kreuzpaintner, Wolfgang

    2010-01-01

    Recent advances in thin-film structuring techniques have generated significant interest in the dynamics of spin waves in magnetic nanostructures and the possible use of inelastic neutron scattering (INS) for their investigation. This thesis describes the design and implementation, at GKSS Research Centre, of equipment for preparation of large and laterally submicron and nanometre structured magnetic samples for such future INS experiments. After a brief resume on spin waves in nanostructures, the development work on new purpose-designed equipment, including high vacuum (HV) argon ion beam milling and ultra high vacuum (UHV) e-beam evaporation setups, is described. Ni nanodot as well as Ni and novel Gd nanowire samples were prepared using combinations of sputter deposition, laser interference lithography, argon ion beam milling, e-beam evaporation and self organisation techniques. With reference to sample preparation, epitaxial growth studies for Ni on Si(100) substrate were performed, resulting in the development of a new deposition process, which by thermal tuning allows for the direct epitaxial growth of Ni on Si with unprecedented crystalline quality. The results of various characterisation experiments on the prepared nanostructured samples, including Scanning Electron Microscopy (SEM), microprobe analysis, Atomic and Magnetic Force Microscopy (AFM/MFM), Vibrating Sample Magnetometry (VSM), X-ray Diffraction (XRD) and Reflectivity (XRR), unpolarised and Polarised Neutron Scattering (PNR) and off-specular scattering by X-rays and neutrons using rocking scans and Time-Of-Flight Grazing Incidence Small Angle Neutron Scattering (TOF-GISANS), together with various analysis procedures such as Distorted-Wave Born Approximation (DWBA), are reported. The analysis of a Gd nanowire sample by TOF-GISANS led to a novel evaluation technique which in comparison with single wavelength methods allows portions of reciprocal space to be scanned without changing the angle of

  6. IXM gas sampling procedure

    International Nuclear Information System (INIS)

    Pingel, L.A.

    1995-01-01

    Ion Exchange Modules (IXMs) are used at the 105-KE and -KW Fuel Storage Basins to control radionuclide concentrations in the water. A potential safety concern relates to production of hydrogen gas by radiolysis of the water trapped in the ion exchange media of spent IXMs. This document provides a procedure for sampling the gases in the head space of the IXM

  7. Sample preparation method for the combined extraction of ethyl glucuronide and drugs of abuse in hair.

    Science.gov (United States)

    Meier, Ulf; Briellmann, Thomas; Scheurer, Eva; Dussy, Franz

    2018-04-01

    Often in hair analysis, a small hair sample is available while the analysis of a multitude of structurally diverse substances with different concentration ranges is demanded. The analysis of the different substances often requires different sample preparation methods, increasing the amount of required hair sample. When segmental hair analysis is necessary, the amount of hair sample needed is further increased. Therefore, the required sample amount for a full analysis can quickly exceed what is available. To combat this problem, a method for the combined hair sample preparation using a single extraction procedure for analysis of ethyl glucuronide with liquid chromatography-multistage fragmentation mass spectrometry/multiple reaction monitoring (LC-MS 3 /MRM) and common drugs of abuse with LC-MRM was developed. The combined sample preparation is achieved by separating ethyl glucuronide from the drugs of abuse into separate extracts by fractionation in the solid-phase extraction step during sample clean-up. A full validation for all substances for the parameters selectivity, linearity, limit of detection, limit of quantification, accuracy, precision, matrix effects, and recovery was successfully completed. The following drugs of abuse were included in the method: Amphetamine; methamphetamine; 3,4-methylenedioxy-N-methylamphetamine (MDMA); 3,4-methylenedioxyamphetamine (MDA); 3,4-methylenedioxy-N-ethylamphetamine (MDE); morphine; 6-monoacetylmorphine; codeine; acetylcodeine; cocaine; benzoylecgonine; norcocaine; cocaethylene; methadone; 2-ethylidene-1,5-dimethyl-3,3-diphenylpyrrolidine (EDDP) and methylphenidate. In conclusion, as only 1 sample preparation is needed with 1 aliquot of hair, the presented sample preparation allows an optimal analysis of both ethyl glucuronide and of the drugs of abuse, even when the sample amount is a limiting factor. Copyright © 2017 John Wiley & Sons, Ltd.

  8. Sample Preparation for Electron Probe Microanalysis-Pushing the Limits.

    Science.gov (United States)

    Geller, Joseph D; Engle, Paul D

    2002-01-01

    There are two fundamental considerations in preparing samples for electron probe microanalysis (EPMA). The first one may seem obvious, but we often find it is overlooked. That is, the sample analyzed should be representative of the population from which it comes. The second is a direct result of the assumptions in the calculations used to convert x-ray intensity ratios, between the sample and standard, to concentrations. Samples originate from a wide range of sources. During their journey to being excited under the electron beam for the production of x rays there are many possibilities for sample alteration. Handling can contaminate samples by adding extraneous matter. In preparation, the various abrasives used in sizing the sample by sawing, grinding and polishing can embed themselves. The most accurate composition of a contaminated sample is, at best, not representative of the original sample; it is misleading. Our laboratory performs EPMA analysis on customer submitted samples and prepares over 250 different calibration standards including pure elements, compounds, alloys, glasses and minerals. This large variety of samples does not lend itself to mass production techniques, including automatic polishing. Our manual preparation techniques are designed individually for each sample. The use of automated preparation equipment does not lend itself to this environment, and is not included in this manuscript. The final step in quantitative electron probe microanalysis is the conversion of x-ray intensities ratios, known as the "k-ratios," to composition (in mass fraction or atomic percent) and/or film thickness. Of the many assumptions made in the ZAF (where these letters stand for atomic number, absorption and fluorescence) corrections the localized geometry between the sample and electron beam, or takeoff angle, must be accurately known. Small angular errors can lead to significant errors in the final results. The sample preparation technique then becomes very

  9. Platelet-rich fibrin prepared from stored whole-blood samples.

    Science.gov (United States)

    Isobe, Kazushige; Suzuki, Masashi; Watanabe, Taisuke; Kitamura, Yutaka; Suzuki, Taiji; Kawabata, Hideo; Nakamura, Masayuki; Okudera, Toshimitsu; Okudera, Hajime; Uematsu, Kohya; Nakata, Koh; Tanaka, Takaaki; Kawase, Tomoyuki

    2017-12-01

    In regenerative therapy, self-clotted platelet concentrates, such as platelet-rich fibrin (PRF), are generally prepared on-site and are immediately used for treatment. If blood samples or prepared clots can be preserved for several days, their clinical applicability will expand. Here, we prepared PRF from stored whole-blood samples and examined their characteristics. Blood samples were collected from non-smoking, healthy male donors (aged 27-67 years, N = 6), and PRF clots were prepared immediately or after storage for 1-2 days. Fibrin fiber was examined by scanning electron microscopy. Bioactivity was evaluated by means of a bioassay system involving human periosteal cells, whereas PDGF-BB concentrations were determined by an enzyme-linked immunosorbent assay. Addition of optimal amounts of a 10% CaCl 2 solution restored the coagulative ability of whole-blood samples that contained an anticoagulant (acid citrate dextrose) and were stored for up to 2 days at ambient temperature. In PRF clots prepared from the stored whole-blood samples, the thickness and cross-links of fibrin fibers were almost identical to those of freshly prepared PRF clots. PDGF-BB concentrations in the PRF extract were significantly lower in stored whole-blood samples than in fresh samples; however, both extracts had similar stimulatory effects on periosteal-cell proliferation. Quality of PRF clots prepared from stored whole-blood samples is not reduced significantly and can be ensured for use in regenerative therapy. Therefore, the proposed method enables a more flexible treatment schedule and choice of a more suitable platelet concentrate immediately before treatment, not after blood collection.

  10. The effect of sample preparation on uranium hydriding

    International Nuclear Information System (INIS)

    Banos, A.; Stitt, C.A.; Scott, T.B.

    2016-01-01

    Highlights: • Distinct differences in uranium hydride growth rates and characteristics between different surface preparation methods. • The primary difference between the categories of sample preparations is the level of strain present in the surface. • Greater surface-strain, leads to higher nucleation number density, implying a preferred attack of strained vs unstrained metal. • As strain is reduced, surface features such as carbides and grain boundaries become more important in controlling the UH3 location. - Abstract: The influence of sample cleaning preparation on the early stages of uranium hydriding has been examined, by using four identical samples but concurrently prepared using four different methods. The samples were reacted together in the same corrosion cell to ensure identical exposure conditions. From the analysis, it was found that the hydride nucleation rate was proportional to the level of strain exhibiting higher number density for the more strained surfaces. Additionally, microstructure of the metal plays a secondary role regarding initial hydrogen attack on the highly strained surfaces yet starts to dominate the system while moving to more pristine samples.

  11. Factors Associated with Anxiety About Colonoscopy: The Preparation, the Procedure, and the Anticipated Findings.

    Science.gov (United States)

    Shafer, L A; Walker, J R; Waldman, C; Yang, C; Michaud, V; Bernstein, C N; Hathout, L; Park, J; Sisler, J; Restall, G; Wittmeier, K; Singh, H

    2018-03-01

    Previous research has assessed anxiety around colonoscopy procedures, but has not considered anxiety related to different aspects related to the colonoscopy process. Before colonoscopy, we assessed anxiety about: bowel preparation, the procedure, and the anticipated results. We evaluated associations between patient characteristics and anxiety in each area. An anonymous survey was distributed to patients immediately prior to their outpatient colonoscopy in six hospitals and two ambulatory care centers in Winnipeg, Canada. Anxiety was assessed using a visual analog scale. For each aspect, logistic regression models were used to explore associations between patient characteristics and high anxiety. A total of 1316 respondents completed the questions about anxiety (52% female, median age 56 years). Anxiety scores > 70 (high anxiety) were reported by 18% about bowel preparation, 29% about the procedure, and 28% about the procedure results. High anxiety about bowel preparation was associated with female sex, perceived unclear instructions, unfinished laxative, and no previous colonoscopies. High anxiety about the procedure was associated with female sex, no previous colonoscopies, and confusing instructions. High anxiety about the results was associated with symptoms as an indication for colonoscopy and instructions perceived as confusing. Fewer people had high anxiety about preparation than about the procedure and findings of the procedure. There are unique predictors of anxiety about each colonoscopy aspect. Understanding the nuanced differences in aspects of anxiety may help to design strategies to reduce anxiety, leading to improved acceptance of the procedure, compliance with preparation instructions, and less discomfort with the procedure.

  12. Comparative evaluation of the US Environmental Protection Agency's and the Oak Ridge Institute for Science and Education's environmental survey and site assessment program field sampling procedures

    International Nuclear Information System (INIS)

    Vitkus, T.J.; Bright, T.L.; Roberts, S.A.

    1997-10-01

    At the request of the U.S. Nuclear Regulatory Commission's (NRC's) Headquarters Office, the Environmental Survey and Site Assessment Program (ESSAP) of the Oak Ridge Institute for Science and Education (ORISE) compared the documented procedures that the U.S. Environmental Protection Agency (EPA) and ESSAP use for collecting environmental samples. The project objectives were to review both organizations' procedures applicable to collecting various sample matrices, compare the procedures for similarities and differences, and then to evaluate the reason for any identified procedural differences and their potential impact on ESSAP's sample data quality. The procedures reviewed included those for sampling surface and subsurface soil, surface and groundwater, vegetation, air, and removable surface contamination. ESSAP obtained copies of relevant EPA documents and reviewed and prepared a tabulated summary of each applicable procedure. The methods for collecting and handling each type of sample were evaluated for differences, and where these were identified, the significance and effect of the differences on analytical quality were determined. The results of the comparison showed that, overall, the procedures and methods that EPA and ESSAP use for sample collection are very similar. The number of minor differences noted were the result of restrictions or procedures necessary to ensure sample integrity and prevent the introduction of interfering compounds when samples are to be analyzed for chemical parameters. For most radio nuclide analyses, these additional procedures are not necessary. Another item noted was EPA's inclusion of steps that reduce the potential for sample cross-contamination by preparing (dressing) a location prior to collecting a sample or removing a portion of a sample prior to containerization

  13. Lithium aluminate spheroids prepared by emulsion procedure

    International Nuclear Information System (INIS)

    Mateos, A.G.; DiBello, P.M.; Zaleski, A.B.

    1991-01-01

    Lithium aluminate powders were prepared by emulsion evaporation method. The procedure involved preparation of water-in-oil emulsion, with the aqueous phase being a solution of Li and Al nitrates. The mixed salts precursor crystallized to gamma-LiAlO 2 at 700C. Single phase LiAlO 2 occurred as μm spherical particles with average crystallite size of 81 angstrom and surface area of 14 M 2 /g. After prolonged heating at 900C, the aluminate powder crystallite size grew by 5 times with a reduction in particle porosity. The emulsion technique promotes close control of particle size and shape of product and the technique facilitates chemical reaction of constituents and sinterability of resulting product

  14. Efficient sample preparation from complex biological samples using a sliding lid for immobilized droplet extractions.

    Science.gov (United States)

    Casavant, Benjamin P; Guckenberger, David J; Beebe, David J; Berry, Scott M

    2014-07-01

    Sample preparation is a major bottleneck in many biological processes. Paramagnetic particles (PMPs) are a ubiquitous method for isolating analytes of interest from biological samples and are used for their ability to thoroughly sample a solution and be easily collected with a magnet. There are three main methods by which PMPs are used for sample preparation: (1) removal of fluid from the analyte-bound PMPs, (2) removal of analyte-bound PMPs from the solution, and (3) removal of the substrate (with immobilized analyte-bound PMPs). In this paper, we explore the third and least studied method for PMP-based sample preparation using a platform termed Sliding Lid for Immobilized Droplet Extractions (SLIDE). SLIDE leverages principles of surface tension and patterned hydrophobicity to create a simple-to-operate platform for sample isolation (cells, DNA, RNA, protein) and preparation (cell staining) without the need for time-intensive wash steps, use of immiscible fluids, or precise pinning geometries. Compared to other standard isolation protocols using PMPs, SLIDE is able to perform rapid sample preparation with low (0.6%) carryover of contaminants from the original sample. The natural recirculation occurring within the pinned droplets of SLIDE make possible the performance of multistep cell staining protocols within the SLIDE by simply resting the lid over the various sample droplets. SLIDE demonstrates a simple easy to use platform for sample preparation on a range of complex biological samples.

  15. Comparison of Three Sample Preparation Procedures for the Quantification of L-Arginine, Asymmetric Dimethylarginine, and Symmetric Dimethylarginine in Human Plasma Using HPLC-FLD

    DEFF Research Database (Denmark)

    Schou-Pedersen, Anne Marie Voigt; Lykkesfeldt, Jens

    2018-01-01

    Increased asymmetric dimethylarginine (ADMA) in human plasma has been associated with reduced generation of nitric oxide, leading to atherosclerotic diseases. ADMA may therefore be an important biomarker for cardiovascular disease. In the present study, three sample preparation techniques were co...... sample preparation of human plasma samples before HPLC-FLD in providing important information regarding elevated ADMA concentrations.......Increased asymmetric dimethylarginine (ADMA) in human plasma has been associated with reduced generation of nitric oxide, leading to atherosclerotic diseases. ADMA may therefore be an important biomarker for cardiovascular disease. In the present study, three sample preparation techniques were...... compared regarding the quantification of L-arginine and ADMA in human plasma: (A) protein precipitation (PP) based on aqueous trichloroacetic acid (TCA), (B) PP using a mixture of ammonia and acetonitrile, and (C) solid-phase extraction (SPE). The samples were analysed by using high-performance liquid...

  16. Sample Preparation for Electron Probe Microanalysis—Pushing the Limits

    Science.gov (United States)

    Geller, Joseph D.; Engle, Paul D.

    2002-01-01

    There are two fundamental considerations in preparing samples for electron probe microanalysis (EPMA). The first one may seem obvious, but we often find it is overlooked. That is, the sample analyzed should be representative of the population from which it comes. The second is a direct result of the assumptions in the calculations used to convert x-ray intensity ratios, between the sample and standard, to concentrations. Samples originate from a wide range of sources. During their journey to being excited under the electron beam for the production of x rays there are many possibilities for sample alteration. Handling can contaminate samples by adding extraneous matter. In preparation, the various abrasives used in sizing the sample by sawing, grinding and polishing can embed themselves. The most accurate composition of a contaminated sample is, at best, not representative of the original sample; it is misleading. Our laboratory performs EPMA analysis on customer submitted samples and prepares over 250 different calibration standards including pure elements, compounds, alloys, glasses and minerals. This large variety of samples does not lend itself to mass production techniques, including automatic polishing. Our manual preparation techniques are designed individually for each sample. The use of automated preparation equipment does not lend itself to this environment, and is not included in this manuscript. The final step in quantitative electron probe microanalysis is the conversion of x-ray intensities ratios, known as the “k-ratios,” to composition (in mass fraction or atomic percent) and/or film thickness. Of the many assumptions made in the ZAF (where these letters stand for atomic number, absorption and fluorescence) corrections the localized geometry between the sample and electron beam, or takeoff angle, must be accurately known. Small angular errors can lead to significant errors in the final results. The sample preparation technique then becomes very

  17. Emanation thermal analysis. Principle of the method, preparation of samples and apparatus

    International Nuclear Information System (INIS)

    Balek, V.; Pentinghaus, H.J.

    1993-12-01

    Principles of the title method are outlined and the sample preparation procedures and instrumental designs are described. The publication is divided into chapters as follows: (I) Introduction; (II) Sample labelling: (II.1) Introducing parent nuclides as a source of inert gas in solid; Distribution of inert gas in the sample; (II.2) Introducing inert gases without parent nuclides (using the recoil effect of nuclear reactions and using ion bombardment); (II.3) Choice of the suitable labelling technique; (III) Equipment for emanation thermal analysis: (III.1) Inert gas detection and measurement of inert gas release rate; (III.2) System of carrier gas flow and stabilization; (IV) Determination of the optimal conditions for radon release rate measurement; (V) Example of ETA measurement. (P.A.). 1 tab., 10 figs. 5 refs

  18. Enhancing sample preparation capabilities for accelerator mass spectrometry radiocarbon and radiocalcium studies

    International Nuclear Information System (INIS)

    Taylor, R.E.

    1991-01-01

    With support provided by the LLNL Accelerator Mass Spectrometry Laboratory, the UCR Radiocarbon Laboratory continued its studies involving sample pretreatment and target preparation for both AMS radiocarbon ( 14 C) and radiocalcium ( 41 Ca) involving applications to archaeologically -- and paleoanthropologically- related samples. With regard to AMS 14 C-related studies, we have extended the development of a series of procedures which have, as their initial goal, the capability to combust several hundred microgram amounts of a chemically-pretreated organic sample and convert the resultant CO 2 to graphitic carbon which will consistently yield relatively high 13 C - ion currents and blanks which will yield, on a consistent basis, 14 C count rates at or below 0.20% modern, giving an 2 sigma age limit of >50,000 yr BP

  19. 40 CFR 205.160-2 - Test sample selection and preparation.

    Science.gov (United States)

    2010-07-01

    ... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Test sample selection and preparation... sample selection and preparation. (a) Vehicles comprising the sample which are required to be tested... maintained in any manner unless such preparation, tests, modifications, adjustments or maintenance are part...

  20. FISHprep: A Novel Integrated Device for Metaphase FISH Sample Preparation

    DEFF Research Database (Denmark)

    Shah, Pranjul Jaykumar; Vedarethinam, Indumathi; Kwasny, Dorota

    2011-01-01

    We present a novel integrated device for preparing metaphase chromosomes spread slides (FISHprep). The quality of cytogenetic analysis from patient samples greatly relies on the efficiency of sample pre-treatment and/or slide preparation. In cytogenetic slide preparation, cell cultures...... are routinely used to process samples (for culture, arrest and fixation of cells) and/or to expand limited amount of samples (in case of prenatal diagnostics). Arguably, this expansion and other sample pretreatments form the longest part of the entire diagnostic protocols spanning over 3–4 days. We present here...... with minimal handling for metaphase FISH slide preparation....

  1. Independent assessment of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) sample preparation quality: Effect of sample preparation on MALDI-MS of synthetic polymers.

    Science.gov (United States)

    Kooijman, Pieter C; Kok, Sander; Honing, Maarten

    2017-02-28

    Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) provides detailed and in-depth information about the molecular characteristics of synthetic polymers. To obtain the most accurate results the sample preparation parameters should be chosen to suit the sample and the aim of the experiment. Because the underlying principles of MALDI are still not fully known, a priori determination of optimal sample preparation protocols is often not possible. Employing an automated sample preparation quality assessment method recently presented by us we quantified the sample preparation quality obtained using various sample preparation protocols. Six conventional matrices with and without added potassium as a cationization agent and six ionic liquid matrices (ILMs) were assessed using poly(ethylene glycol) (PEG), polytetrahydrofuran (PTHF) and poly(methyl methacrylate) (PMMA) as samples. All sample preparation protocols were scored and ranked based on predefined quality parameters and spot-to-spot repeatability. Clearly distinctive preferences were observed in matrix identity and cationization agent for PEG, PTHF and PMMA, as the addition of an excess of potassium cationization agent results in an increased score for PMMA and a contrasting matrix-dependent effect for PTHF and PEG. The addition of excess cationization agent to sample mixtures dissipates any overrepresentation of high molecular weight polymer species. Our results show reduced ionization efficiency and similar sample deposit homogeneity for all tested ILMs, compared with well-performing conventional MALDI matrices. The results published here represent a start in the unsupervised quantification of sample preparation quality for MALDI samples. This method can select the best sample preparation parameters for any synthetic polymer sample and the results can be used to formulate hypotheses on MALDI principles. Copyright © 2016 John Wiley & Sons, Ltd. Copyright © 2016 John Wiley & Sons, Ltd.

  2. Methods of biological fluids sample preparation - biogenic amines, methylxanthines, water-soluble vitamins.

    Science.gov (United States)

    Płonka, Joanna

    2015-01-01

    In recent years demands on the amount of information that can be obtained from the analysis of a single sample have increased. For time and economic reasons it is necessary to examine at the same time larger number of compounds, and compounds from different groups. This can best be seen in such areas as clinical analysis. In many diseases, the best results for patients are obtained when treatment fits the individual characteristics of the patient. Dosage monitoring is important at the beginning of therapy and in the full process of treatment. In the treatment of many diseases biogenic amines (dopamine, serotonin) and methylxanthines (theophylline, theobromine, caffeine) play an important role. They are used as drugs separately or in combination with others to support and strengthen the action of other drugs - for example, the combination of caffeine and paracetamol. Vitamin supplementation may be also an integral part of the treatment process. Specification of complete sample preparation parameters for extraction of the above compounds from biological matrices has been reviewed. Particular attention was given to the preparation stage and extraction methods. This review provides universal guidance on establishing a common procedures across laboratories to facilitate the preparation and analysis of all discussed compounds. Copyright © 2014 John Wiley & Sons, Ltd.

  3. Development of a versatile sample preparation method and its application for rare-earth pattern and Nd isotope ratio analysis in nuclear forensics

    International Nuclear Information System (INIS)

    Krajko, J.

    2015-01-01

    An improved sample preparation procedure for trace-levels of lanthanides in uranium-bearing samples was developed. The method involves a simple co-precipitation using Fe(III) carrier in ammonium carbonate medium to remove the uranium matrix. The procedure is an effective initial pre-concentration step for the subsequent extraction chromatographic separations. The applicability of the method was demonstrated by the measurement of REE pattern and 143 Nd/ 144 Nd isotope ratio in uranium ore concentrate samples. (author)

  4. GeLC-MS: A Sample Preparation Method for Proteomics Analysis of Minimal Amount of Tissue.

    Science.gov (United States)

    Makridakis, Manousos; Vlahou, Antonia

    2017-10-10

    Application of various proteomics methodologies have been implemented for the global and targeted proteome analysis of many different types of biological samples such as tissue, urine, plasma, serum, blood, and cell lines. Among the aforementioned biological samples, tissue has an exceptional role into clinical research and practice. Disease initiation and progression is usually located at the tissue level of different organs, making the analysis of this material very important for the understanding of the disease pathophysiology. Despite the significant advances in the mass spectrometry instrumentation, tissue proteomics still faces several challenges mainly due to increased sample complexity and heterogeneity. However, the most prominent challenge is attributed to the invasive procedure of tissue sampling which restricts the availability of fresh frozen tissue to minimal amounts and limited number of samples. Application of GeLC-MS sample preparation protocol for tissue proteomics analysis can greatly facilitate making up for these difficulties. In this chapter, a step by step guide for the proteomics analysis of minute amounts of tissue samples using the GeLC-MS sample preparation protocol, as applied by our group in the analysis of multiple different types of tissues (vessels, kidney, bladder, prostate, heart) is provided.

  5. Procedure for preparation of dispersions

    International Nuclear Information System (INIS)

    1978-01-01

    Procedure for the preparation of a water based dispersion of cerium oxide, characterised in that a suspension of cerium (IV) hydroxide is formed with an acid, where the acid is in the state of a disaggregation of aggregated crystalline cerium hydroxide, the suspension being preheated for a specified time and to a specified temperature, so that the pH value becomes constant, and whereby the quantity of acid in the suspension is such that the constant pH value is lower than 5.4, so that a conditioned suspension may be obtained, and water may be mixed with the conditioned suspension for making a water based dispersion of cerium oxide. (G.C.)

  6. Review of online coupling of sample preparation techniques with liquid chromatography.

    Science.gov (United States)

    Pan, Jialiang; Zhang, Chengjiang; Zhang, Zhuomin; Li, Gongke

    2014-03-07

    Sample preparation is still considered as the bottleneck of the whole analytical procedure, and efforts has been conducted towards the automation, improvement of sensitivity and accuracy, and low comsuption of organic solvents. Development of online sample preparation techniques (SP) coupled with liquid chromatography (LC) is a promising way to achieve these goals, which has attracted great attention. This article reviews the recent advances on the online SP-LC techniques. Various online SP techniques have been described and summarized, including solid-phase-based extraction, liquid-phase-based extraction assisted with membrane, microwave assisted extraction, ultrasonic assisted extraction, accelerated solvent extraction and supercritical fluids extraction. Specially, the coupling approaches of online SP-LC systems and the corresponding interfaces have been discussed and reviewed in detail, such as online injector, autosampler combined with transport unit, desorption chamber and column switching. Typical applications of the online SP-LC techniques have been summarized. Then the problems and expected trends in this field are attempted to be discussed and proposed in order to encourage the further development of online SP-LC techniques. Copyright © 2014 Elsevier B.V. All rights reserved.

  7. Congener Production in Blood Samples During Preparation and Storage

    DEFF Research Database (Denmark)

    Felby, Søren; Nielsen, Erik

    1995-01-01

    Retsmedicin, congener production, preparation, head space GC, acetone, isobutanol, storage, blood samples, n-propanol, methanol, methylethylketone......Retsmedicin, congener production, preparation, head space GC, acetone, isobutanol, storage, blood samples, n-propanol, methanol, methylethylketone...

  8. Comparison of different procedures to prepare platelet-rich plasma for studies of platelet aggregation by light transmission aggregometry.

    Science.gov (United States)

    Femia, Eti Alessandra; Pugliano, Mariateresa; Podda, Gianmarco; Cattaneo, Marco

    2012-01-01

    Light transmission aggregometry (LTA), the gold standard for the study of patients with defects of platelet function, is a poorly standardized technique. The guidelines that have been produced so far are largely based on consensus of experts, due to the absence of studies directly comparing different procedures. Therefore, ad hoc studies are needed to gather scientific evidence on how to choose the most appropriate procedures for LTA measurement. In this study, we aimed at evaluating the most appropriate conditions for preparing samples of platelet-rich plasma (PRP) for studies of platelet aggregation by LTA. Citrate-anticoagulated blood from 32 individuals was centrifuged at 150, 200, 250 or 300×g at room temperature for 10 min. Red blood cells contamination was highest in PRP prepared at 150×g; mean platelet volume (MPV) was lowest in PRP prepared at 300×g. The extent of platelet aggregation measured by LTA was lower and more variable in PRP prepared at 300×g. Therefore, centrifugation of blood at 200×g or 250×g for 10 min appears to be the best condition for preparing PRP for LTA studies.

  9. Methodology for sample preparation and size measurement of commercial ZnO nanoparticles

    Directory of Open Access Journals (Sweden)

    Pei-Jia Lu

    2018-04-01

    Full Text Available This study discusses the strategies on sample preparation to acquire images with sufficient quality for size characterization by scanning electron microscope (SEM using two commercial ZnO nanoparticles of different surface properties as a demonstration. The central idea is that micrometer sized aggregates of ZnO in powdered forms need to firstly be broken down to nanosized particles through an appropriate process to generate nanoparticle dispersion before being deposited on a flat surface for SEM observation. Analytical tools such as contact angle, dynamic light scattering and zeta potential have been utilized to optimize the procedure for sample preparation and to check the quality of the results. Meanwhile, measurements of zeta potential values on flat surfaces also provide critical information and save lots of time and efforts in selection of suitable substrate for particles of different properties to be attracted and kept on the surface without further aggregation. This simple, low-cost methodology can be generally applied on size characterization of commercial ZnO nanoparticles with limited information from vendors. Keywords: Zinc oxide, Nanoparticles, Methodology

  10. Trends in sample preparation 2002. Development and application. Book of abstracts

    International Nuclear Information System (INIS)

    Wenzl, T.; Eberl, M.; Zischka, M.; Knapp, G.

    2002-01-01

    This conference comprised topics dealing with sample preparation such as: sample decomposition, solvent extraction, derivatization techniques and uncertainty in sample preparation. In particular microwave assisted sample preparation techniques and equipment were discussed. The papers were organized under the general topics: trace element analysis, trace analysis of organic compounds, high performance instrumentation in sample preparation, speciation analysis and posters session. Those papers of INIS interest are cited individually. (nevyjel)

  11. Trends in sample preparation 2002. Development and application. Book of abstracts

    Energy Technology Data Exchange (ETDEWEB)

    Wenzl, T; Eberl, M; Zischka, M; Knapp, G [eds.

    2002-07-01

    This conference comprised topics dealing with sample preparation such as: sample decomposition, solvent extraction, derivatization techniques and uncertainty in sample preparation. In particular microwave assisted sample preparation techniques and equipment were discussed. The papers were organized under the general topics: trace element analysis, trace analysis of organic compounds, high performance instrumentation in sample preparation, speciation analysis and posters session. Those papers of INIS interest are cited individually. (nevyjel)

  12. Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction

    Energy Technology Data Exchange (ETDEWEB)

    Pena, M.T.; Pensado, Luis; Casais, M.C.; Mejuto, M.C.; Cela, Rafael [Universidad de Santiago de Compostela, Dpto. Quimica Analitica, Nutricion y Bromatologia. Instituto de Investigacion y Analisis Alimentario, Santiago de Compostela (Spain)

    2007-04-15

    A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 {mu}g kg{sup -1} dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials. (orig.)

  13. Sample preparation of sewage sludge and soil samples for the determination of polycyclic aromatic hydrocarbons based on one-pot microwave-assisted saponification and extraction.

    Science.gov (United States)

    Pena, M Teresa; Pensado, Luis; Casais, M Carmen; Mejuto, M Carmen; Cela, Rafael

    2007-04-01

    A microwave-assisted sample preparation (MASP) procedure was developed for the analysis of polycyclic aromatic hydrocarbons (PAHs) in sewage sludge and soil samples. The procedure involved the simultaneous microwave-assisted extraction of PAHs with n-hexane and the hydrolysis of samples with methanolic potassium hydroxide. Because of the complex nature of the samples, the extracts were submitted to further cleaning with silica and Florisil solid-phase extraction cartridges connected in series. Naphthalene, acenaphthene, fluorene, phenanthrene, anthracene, fluoranthene, pyrene, benz[a]anthracene, chrysene, benzo[e]pyrene, benzo[b]fluoranthene, benzo[k]fluoranthene, benzo[a]pyrene, dibenz[a,h]anthracene, benzo[g,h,i]perylene, and indeno[1,2,3-cd]pyrene, were considered in the study. Quantification limits obtained for all of these compounds (between 0.4 and 14.8 microg kg(-1) dry mass) were well below of the limits recommended in the USA and EU. Overall recovery values ranged from 60 to 100%, with most losses being due to evaporation in the solvent exchange stages of the procedure, although excellent extraction recoveries were obtained. Validation of the accuracy was carried out with BCR-088 (sewage sludge) and BCR-524 (contaminated industrial soil) reference materials.

  14. Novel sample preparation method for surfactant containing suppositories: effect of micelle formation on drug recovery.

    Science.gov (United States)

    Kalmár, Éva; Ueno, Konomi; Forgó, Péter; Szakonyi, Gerda; Dombi, György

    2013-09-01

    Rectal drug delivery is currently at the focus of attention. Surfactants promote drug release from the suppository bases and enhance the formulation properties. The aim of our work was to develop a sample preparation method for HPLC analysis for a suppository base containing 95% hard fat, 2.5% Tween 20 and 2.5% Tween 60. A conventional sample preparation method did not provide successful results as the recovery of the drug failed to fulfil the validation criterion 95-105%. This was caused by the non-ionic surfactants in the suppository base incorporating some of the drug, preventing its release. As guidance for the formulation from an analytical aspect, we suggest a well defined surfactant content based on the turbidimetric determination of the CMC (critical micelle formation concentration) in the applied methanol-water solvent. Our CMC data correlate well with the results of previous studies. As regards the sample preparation procedure, a study was performed of the effects of ionic strength and pH on the drug recovery with the avoidance of degradation of the drug during the procedure. Aminophenazone and paracetamol were used as model drugs. The optimum conditions for drug release from the molten suppository base were found to be 100 mM NaCl, 20-40 mM NaOH and a 30 min ultrasonic treatment of the final sample solution. As these conditions could cause the degradation of the drugs in the solution, this was followed by NMR spectroscopy, and the results indicated that degradation did not take place. The determined CMCs were 0.08 mM for Tween 20, 0.06 mM for Tween 60 and 0.04 mM for a combined Tween 20, Tween 60 system. Copyright © 2013 Elsevier B.V. All rights reserved.

  15. Molecularly imprinted polymers for sample preparation and biosensing in food analysis: Progress and perspectives.

    Science.gov (United States)

    Ashley, Jon; Shahbazi, Mohammad-Ali; Kant, Krishna; Chidambara, Vinayaka Aaydha; Wolff, Anders; Bang, Dang Duong; Sun, Yi

    2017-05-15

    Molecularly imprinted polymers (MIPs) are biomimetics which can selectively bind to analytes of interest. One of the most interesting areas where MIPs have shown the biggest potential is food analysis. MIPs have found use as sorbents in sample preparation attributed to the high selectivity and high loading capacity. MIPs have been intensively employed in classical solid-phase extraction and solid-phase microextraction. More recently, MIPs have been combined with magnetic bead extraction, which greatly simplifies sample handling procedures. Studies have consistently shown that MIPs can effectively minimize complex food matrix effects, and improve recoveries and detection limits. In addition to sample preparation, MIPs have also been viewed as promising alternatives to bio-receptors due to the inherent molecular recognition abilities and the high stability in harsh chemical and physical conditions. MIPs have been utilized as receptors in biosensing platforms such as electrochemical, optical and mass biosensors to detect various analytes in food. In this review, we will discuss the current state-of-the-art of MIP synthesis and applications in the context of food analysis. We will highlight the imprinting methods which are applicable for imprinting food templates, summarize the recent progress in using MIPs for preparing and analysing food samples, and discuss the current limitations in the commercialisation of MIPs technology. Finally, future perspectives will be given. Copyright © 2017 Elsevier B.V. All rights reserved.

  16. On-line Automated Sample Preparation-Capillary Gas Chromatography for the Analysis of Plasma Samples.

    NARCIS (Netherlands)

    Louter, A.J.H.; van der Wagt, R.A.C.A.; Brinkman, U.A.T.

    1995-01-01

    An automated sample preparation module, (the automated sample preparation with extraction columns, ASPEC), was interfaced with a capillary gas chromatograph (GC) by means of an on-column interface. The system was optimised for the determination of the antidepressant trazodone in plasma. The clean-up

  17. Cr(VI) generation during sample preparation of solid samples – A ...

    African Journals Online (AJOL)

    Cr(VI) generation during sample preparation of solid samples – A chromite ore case study. R.I Glastonbury, W van der Merwe, J.P Beukes, P.G van Zyl, G Lachmann, C.J.H Steenkamp, N.F Dawson, M.H Stewart ...

  18. Sample preparation for semivolatile organics analysis of Hanford single-shell tank waste with high nitrate/nitrite and water content

    International Nuclear Information System (INIS)

    Stromatt, R.W.; Hoppe, E.W.; Steele, M.J.

    1993-11-01

    This report describes research work carried out to solve sample preparation problems associated with applying gas chromatography with mass spectrometric detection (GC/MS) to the analysis of single shell tank (SST) samples from Hanford for semivolatile organic compounds. Poor performance was found when applying the procedures based on the U.S. Environmental Protection Agency (EPA), Contract Laboratory Program, Statement of Work (CLP SOW). Analysis work was carried out on simulated drainable liquid modeled after the SST core samples which had evidenced analysis problems. Some work was also conducted on true SST samples. It was found that the pH range was too broad in the original procedure. It was also found that by decreasing the amount of methanol used in the extraction process, problems associated with the formation of an azeotrope phase could be avoided. The authors suggest a new procedure, whose eventual application to a wide array of SST samples will lend itself to better quality control limits

  19. An Automated Inpatient Split-dose Bowel Preparation System Improves Colonoscopy Quality and Reduces Repeat Procedures.

    Science.gov (United States)

    Yadlapati, Rena; Johnston, Elyse R; Gluskin, Adam B; Gregory, Dyanna L; Cyrus, Rachel; Werth, Lindsay; Ciolino, Jody D; Grande, David P; Keswani, Rajesh N

    2017-07-19

    Inpatient colonoscopy preparations are often inadequate, compromising patient safety and procedure quality, while resulting in greater hospital costs. The aims of this study were to: (1) design and implement an electronic inpatient split-dose bowel preparation order set; (2) assess the intervention's impact upon preparation adequacy, repeated colonoscopies, hospital days, and costs. We conducted a single center prospective pragmatic quasiexperimental study of hospitalized adults undergoing colonoscopy. The experimental intervention was designed using DMAIC (define, measure, analyze, improve, and control) methodology. Prospective data collected over 12 months were compared with data from a historical preintervention cohort. The primary outcome was bowel preparation quality and secondary outcomes included number of repeated procedures, hospital days, and costs. On the basis of a Delphi method and DMAIC process, we created an electronic inpatient bowel preparation order set inclusive of a split-dose bowel preparation algorithm, automated orders for rescue medications, and nursing bowel preparation checks. The analysis data set included 969 patients, 445 (46%) in the postintervention group. The adequacy of bowel preparation significantly increased following intervention (86% vs. 43%; P<0.01) and proportion of repeated procedures decreased (2.0% vs. 4.6%; P=0.03). Mean hospital days from bowel preparation initiation to discharge decreased from 8.0 to 6.9 days (P=0.02). The intervention resulted in an estimated 1-year cost-savings of $46,076 based on a reduction in excess hospital days associated with repeated and delayed procedures. Our interdisciplinary initiative targeting inpatient colonoscopy preparations significantly improved quality and reduced repeat procedures, and hospital days. Other institutions should consider utilizing this framework to improve inpatient colonoscopy value.

  20. Solid phase extraction for sample preparation in trace analysis of ionogenic compounds by capillary isotachophoresis

    International Nuclear Information System (INIS)

    Hutta, M.; Kaniansky, D.; Simunicova, E.; Zelenska, V.; Madajova, V.; Siskova, A.

    1992-01-01

    Various sorbents recommended for solid phase extraction (SPE) in sample preparation procedures were studied for use in combination with capillary isotachophoresis (ITP). They were very efficient in achieving trace concentration levels (low ppb, i.e., low parts per 10 9 ) for different types of ITP analytes present in environmental and biological matrices. A macroporous carbon sorbent was convenient for sample preparation in ITP analysis of short chain fatty acids (C 4 -C 9 ) in drinking water. Chelating sorbents based on hydroxyalkyl methacrylate matrix with salicylate, thioglycolate and 8-hydroxyquinolinate functionalities were found to be very suitable for preconcentration of heavy metals with an inherent sample clean-up. An octadecyl-bonded silica sorbent enabled in ITP a photometric detection of γ-aminobutyrate (labeled with a 2,4,6-trinitrophenyl group) at concentrations considerably lower than required for the determination of this amino acid in cerebrospinal fluid (∼5*10 -8 mol/l). (author) 34 refs.; 3 figs.; 1 tab

  1. Standard practices for sampling uranium-Ore concentrate

    CERN Document Server

    American Society for Testing and Materials. Philadelphia

    2010-01-01

    1.1 These practices are intended to provide the nuclear industry with procedures for obtaining representative bulk samples from uranium-ore concentrates (UOC) (see Specification C967). 1.2 These practices also provide for obtaining a series of representative secondary samples from the original bulk sample for the determination of moisture and other test purposes, and for the preparation of pulverized analytical samples (see Test Methods C1022). 1.3 These practices consist of a number of alternative procedures for sampling and sample preparation which have been shown to be satisfactory through long experience in the nuclear industry. These procedures are described in the following order. Stage Procedure Section Primary Sampling One-stage falling stream 4 Two-stage falling stream 5 Auger 6 Secondary Sampling Straight-path (reciprocating) 7 Rotating (Vezin) 8, 9 Sample Preparation 10 Concurrent-drying 11-13 Natural moisture 14-16 Calcination 17, 18 Sample Packaging 19 Wax s...

  2. A novel sample preparation method to avoid influence of embedding medium during nano-indentation

    Science.gov (United States)

    Meng, Yujie; Wang, Siqun; Cai, Zhiyong; Young, Timothy M.; Du, Guanben; Li, Yanjun

    2013-02-01

    The effect of the embedding medium on the nano-indentation measurements of lignocellulosic materials was investigated experimentally using nano-indentation. Both the reduced elastic modulus and the hardness of non-embedded cell walls were found to be lower than those of the embedded samples, proving that the embedding medium used for specimen preparation on cellulosic material during nano-indentation can modify cell-wall properties. This leads to structural and chemical changes in the cell-wall constituents, changes that may significantly alter the material properties. Further investigation was carried out to detect the influence of different vacuum times on the cell-wall mechanical properties during the embedding procedure. Interpretation of the statistical analysis revealed no linear relationships between vacuum time and the mechanical properties of cell walls. The quantitative measurements confirm that low-viscosity resin has a rapid penetration rate early in the curing process. Finally, a novel sample preparation method aimed at preventing resin diffusion into lignocellulosic cell walls was developed using a plastic film to wrap the sample before embedding. This method proved to be accessible and straightforward for many kinds of lignocellulosic material, but is especially suitable for small, soft samples.

  3. Critical evaluation of sample pretreatment techniques.

    Science.gov (United States)

    Hyötyläinen, Tuulia

    2009-06-01

    Sample preparation before chromatographic separation is the most time-consuming and error-prone part of the analytical procedure. Therefore, selecting and optimizing an appropriate sample preparation scheme is a key factor in the final success of the analysis, and the judicious choice of an appropriate procedure greatly influences the reliability and accuracy of a given analysis. The main objective of this review is to critically evaluate the applicability, disadvantages, and advantages of various sample preparation techniques. Particular emphasis is placed on extraction techniques suitable for both liquid and solid samples.

  4. Current trends in sample preparation for cosmetic analysis.

    Science.gov (United States)

    Zhong, Zhixiong; Li, Gongke

    2017-01-01

    The widespread applications of cosmetics in modern life make their analysis particularly important from a safety point of view. There is a wide variety of restricted ingredients and prohibited substances that primarily influence the safety of cosmetics. Sample preparation for cosmetic analysis is a crucial step as the complex matrices may seriously interfere with the determination of target analytes. In this review, some new developments (2010-2016) in sample preparation techniques for cosmetic analysis, including liquid-phase microextraction, solid-phase microextraction, matrix solid-phase dispersion, pressurized liquid extraction, cloud point extraction, ultrasound-assisted extraction, and microwave digestion, are presented. Furthermore, the research and progress in sample preparation techniques and their applications in the separation and purification of allowed ingredients and prohibited substances are reviewed. © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  5. The Recent Developments in Sample Preparation for Mass Spectrometry-Based Metabolomics.

    Science.gov (United States)

    Gong, Zhi-Gang; Hu, Jing; Wu, Xi; Xu, Yong-Jiang

    2017-07-04

    Metabolomics is a critical member in systems biology. Although great progress has been achieved in metabolomics, there are still some problems in sample preparation, data processing and data interpretation. In this review, we intend to explore the roles, challenges and trends in sample preparation for mass spectrometry- (MS-) based metabolomics. The newly emerged sample preparation methods were also critically examined, including laser microdissection, in vivo sampling, dried blood spot, microwave, ultrasound and enzyme-assisted extraction, as well as microextraction techniques. Finally, we provide some conclusions and perspectives for sample preparation in MS-based metabolomics.

  6. An overview of the main foodstuff sample preparation technologies for tetracycline residue determination.

    Science.gov (United States)

    Pérez-Rodríguez, Michael; Pellerano, Roberto Gerardo; Pezza, Leonardo; Pezza, Helena Redigolo

    2018-05-15

    Tetracyclines are widely used for both the treatment and prevention of diseases in animals as well as for the promotion of rapid animal growth and weight gain. This practice may result in trace amounts of these drugs in products of animal origin, such as milk and eggs, posing serious risks to human health. The presence of tetracycline residues in foods can lead to the transmission of antibiotic-resistant pathogenic bacteria through the food chain. In order to ensure food safety and avoid exposure to these substances, national and international regulatory agencies have established tolerance levels for authorized veterinary drugs, including tetracycline antimicrobials. In view of that, numerous sensitive and specific methods have been developed for the quantification of these compounds in different food matrices. One will note, however, that the determination of trace residues in foods such as milk and eggs often requires extensive sample extraction and preparation prior to conducting instrumental analysis. Sample pretreatment is usually the most complicated step in the analytical process and covers both cleaning and pre-concentration. Optimal sample preparation can reduce analysis time and sources of error, enhance sensitivity, apart from enabling unequivocal identification, confirmation and quantification of target analytes. The development and implementation of more environmentally friendly analytical procedures, which involve the use of less hazardous solvents and smaller sample sizes compared to traditional methods, is a rapidly increasing trend in analytical chemistry. This review seeks to provide an updated overview of the main trends in sample preparation for the determination of tetracycline residues in foodstuffs. The applicability of several extraction and clean-up techniques employed in the analysis of foodstuffs, especially milk and egg samples, is also thoroughly discussed. Copyright © 2018 Elsevier B.V. All rights reserved.

  7. Optimized cryo-focused ion beam sample preparation aimed at in situ structural studies of membrane proteins.

    Science.gov (United States)

    Schaffer, Miroslava; Mahamid, Julia; Engel, Benjamin D; Laugks, Tim; Baumeister, Wolfgang; Plitzko, Jürgen M

    2017-02-01

    While cryo-electron tomography (cryo-ET) can reveal biological structures in their native state within the cellular environment, it requires the production of high-quality frozen-hydrated sections that are thinner than 300nm. Sample requirements are even more stringent for the visualization of membrane-bound protein complexes within dense cellular regions. Focused ion beam (FIB) sample preparation for transmission electron microscopy (TEM) is a well-established technique in material science, but there are only few examples of biological samples exhibiting sufficient quality for high-resolution in situ investigation by cryo-ET. In this work, we present a comprehensive description of a cryo-sample preparation workflow incorporating additional conductive-coating procedures. These coating steps eliminate the adverse effects of sample charging on imaging with the Volta phase plate, allowing data acquisition with improved contrast. We discuss optimized FIB milling strategies adapted from material science and each critical step required to produce homogeneously thin, non-charging FIB lamellas that make large areas of unperturbed HeLa and Chlamydomonas cells accessible for cryo-ET at molecular resolution. Copyright © 2016 Elsevier Inc. All rights reserved.

  8. 7 CFR 61.34 - Drawing and preparation of sample.

    Science.gov (United States)

    2010-01-01

    ... 7 Agriculture 3 2010-01-01 2010-01-01 false Drawing and preparation of sample. 61.34 Section 61.34 Agriculture Regulations of the Department of Agriculture (Continued) AGRICULTURAL MARKETING SERVICE (Standards... Cottonseed Samplers § 61.34 Drawing and preparation of sample. Each licensed cottonseed sampler shall draw...

  9. Matrix removal in state of the art sample preparation methods for serum by charged aerosol detection and metabolomics-based LC-MS.

    Science.gov (United States)

    Schimek, Denise; Francesconi, Kevin A; Mautner, Anton; Libiseller, Gunnar; Raml, Reingard; Magnes, Christoph

    2016-04-07

    Investigations into sample preparation procedures usually focus on analyte recovery with no information provided about the fate of other components of the sample (matrix). For many analyses, however, and particularly those using liquid chromatography-mass spectrometry (LC-MS), quantitative measurements are greatly influenced by sample matrix. Using the example of the drug amitriptyline and three of its metabolites in serum, we performed a comprehensive investigation of nine commonly used sample clean-up procedures in terms of their suitability for preparing serum samples. We were monitoring the undesired matrix compounds using a combination of charged aerosol detection (CAD), LC-CAD, and a metabolomics-based LC-MS/MS approach. In this way, we compared analyte recovery of protein precipitation-, liquid-liquid-, solid-phase- and hybrid solid-phase extraction methods. Although all methods provided acceptable recoveries, the highest recovery was obtained by protein precipitation with acetonitrile/formic acid (amitriptyline 113%, nortriptyline 92%, 10-hydroxyamitriptyline 89%, and amitriptyline N-oxide 96%). The quantification of matrix removal by LC-CAD showed that the solid phase extraction method (SPE) provided the lowest remaining matrix load (48-123 μg mL(-1)), which is a 10-40 fold better matrix clean-up than the precipitation- or hybrid solid phase extraction methods. The metabolomics profiles of eleven compound classes, comprising 70 matrix compounds showed the trends of compound class removal for each sample preparation strategy. The collective data set of analyte recovery, matrix removal and matrix compound profile was used to assess the effectiveness of each sample preparation method. The best performance in matrix clean-up and practical handling of small sample volumes was showed by the SPE techniques, particularly HLB SPE. CAD proved to be an effective tool for revealing the considerable differences between the sample preparation methods. This detector can

  10. Tooth enamel sample preparation using alkaline treatment in ESR dosimetry

    International Nuclear Information System (INIS)

    Yongzeng, Zhou; Jiadong, Wang; Xiaomei, Jia; Ke, Wu; Jianbo, Cong

    2002-01-01

    Tooth enamel sample preparation using alkaline treatment was studied and compared with traditional mechanical method in this paper. 20 adult teeth were used. Samples were placed into NaOH solution. This method requires 4-5 weeks and the enamel was separated from dentin. Experimental results show that 8M NaOH was appropriate for separating enamel from dentin and that there is no difference in background signal relative intensity between samples prepared by mechanical and by chemical methods. There is also no difference in radiosensitivity between samples prepared by two methods mentioned above. Dose response curve for tooth enamel samples isolated by 8M NaOH solution was obtained

  11. Sample preparation for special PIE-techniques at ITU

    International Nuclear Information System (INIS)

    Toscano, E.H.; Manzel, R.

    2002-01-01

    Several sample preparation techniques were developed and installed in hot cells. The techniques were conceived to evaluate the performance of highly burnt fuel rods and include: (a) a device for the removal of the fuel, (b) a method for the preparation of the specimen ends for the welding of new end caps and for the careful cleaning of samples for Transmission Electron Microscopy and Glow Discharge Mass Spectroscopy, (c) a sample pressurisation device for long term creep tests, and (d) a diameter measuring device for creep or burst samples. Examples of the determination of the mechanical properties, the behaviour under transient conditions and for the assessment of the corrosion behaviour of high burnup cladding materials are presented. (author)

  12. High-throughput automated microfluidic sample preparation for accurate microbial genomics.

    Science.gov (United States)

    Kim, Soohong; De Jonghe, Joachim; Kulesa, Anthony B; Feldman, David; Vatanen, Tommi; Bhattacharyya, Roby P; Berdy, Brittany; Gomez, James; Nolan, Jill; Epstein, Slava; Blainey, Paul C

    2017-01-27

    Low-cost shotgun DNA sequencing is transforming the microbial sciences. Sequencing instruments are so effective that sample preparation is now the key limiting factor. Here, we introduce a microfluidic sample preparation platform that integrates the key steps in cells to sequence library sample preparation for up to 96 samples and reduces DNA input requirements 100-fold while maintaining or improving data quality. The general-purpose microarchitecture we demonstrate supports workflows with arbitrary numbers of reaction and clean-up or capture steps. By reducing the sample quantity requirements, we enabled low-input (∼10,000 cells) whole-genome shotgun (WGS) sequencing of Mycobacterium tuberculosis and soil micro-colonies with superior results. We also leveraged the enhanced throughput to sequence ∼400 clinical Pseudomonas aeruginosa libraries and demonstrate excellent single-nucleotide polymorphism detection performance that explained phenotypically observed antibiotic resistance. Fully-integrated lab-on-chip sample preparation overcomes technical barriers to enable broader deployment of genomics across many basic research and translational applications.

  13. A high-throughput robotic sample preparation system and HPLC-MS/MS for measuring urinary anatabine, anabasine, nicotine and major nicotine metabolites.

    Science.gov (United States)

    Wei, Binnian; Feng, June; Rehmani, Imran J; Miller, Sharyn; McGuffey, James E; Blount, Benjamin C; Wang, Lanqing

    2014-09-25

    Most sample preparation methods characteristically involve intensive and repetitive labor, which is inefficient when preparing large numbers of samples from population-scale studies. This study presents a robotic system designed to meet the sampling requirements for large population-scale studies. Using this robotic system, we developed and validated a method to simultaneously measure urinary anatabine, anabasine, nicotine and seven major nicotine metabolites: 4-Hydroxy-4-(3-pyridyl)butanoic acid, cotinine-N-oxide, nicotine-N-oxide, trans-3'-hydroxycotinine, norcotinine, cotinine and nornicotine. We analyzed robotically prepared samples using high-performance liquid chromatography (HPLC) coupled with triple quadrupole mass spectrometry in positive electrospray ionization mode using scheduled multiple reaction monitoring (sMRM) with a total runtime of 8.5 min. The optimized procedure was able to deliver linear analyte responses over a broad range of concentrations. Responses of urine-based calibrators delivered coefficients of determination (R(2)) of >0.995. Sample preparation recovery was generally higher than 80%. The robotic system was able to prepare four 96-well plate (384 urine samples) per day, and the overall method afforded an accuracy range of 92-115%, and an imprecision of labor-saving for sample preparation, making it efficient and practical for routine measurements in large population-scale studies such as the National Health and Nutrition Examination Survey (NHANES) and the Population Assessment of Tobacco and Health (PATH) study. Published by Elsevier B.V.

  14. Alteration in sample preparation to increase the yield of multiplex Polymerase Chain Reaction assay for diagnosis of genital ulcer disease

    Directory of Open Access Journals (Sweden)

    G Rao

    2013-01-01

    Full Text Available Purpose: Genital Ulcer Disease (GUD is common sexually transmitted infection (STI. Multiple studies have shown that GUDs are strongly associated with the transmission and the acquisition of HIV infection. An accurate diagnosis of common etiology of GUD namely Herpes, syphilis and Chancroid is possible using Multiplex PCR (M-PCR. However, frequent presence of Polymerase Chain Reaction inhibitors in the ulcer swab specimen limits the performance of the assay. In order to overcome this problem, alternative specimen preparation method was used. Materials and Methods: To determine the common etiology, GUD specimens obtained under an STI operations research study were tested with M-PCR after the samples were prepared using Roche Amplicor specimen preparation kit. PCR inhibiting samples were identified from that, which showed negative results. These samples were subjected to phenol-chloroform extraction and ethanol precipitation before the conduct of M-PCR on them. Results: Of the 237 GUD specimens tested, in 145 etiologies could be detected, whereas 92 samples were found negative. Further spiking with one of the target DNA, 128 of the negative samples were found to contain the inhibitors. These 126 samples were then subjected to phenol chloroform extraction and ethanol precipitation followed by M-PCR. Using this method for sample preparation, etiology could be determined in 46 (23% additional samples. This success rate of altered sample preparation method has been lower than that has reported. Conclusion: The results indicate that sample preparation using phenol chloroform extraction and ethanol precipitation, prior to M-PCR helps to eliminate the inhibitors and increase the yield of the assay. However, being a laborious procedure, it may be used for samples giving negative results after the screening by Roche Amplicor specimen preparation kit.

  15. Sample preparations for spark source mass spectrography

    International Nuclear Information System (INIS)

    Catlett, C.W.; Rollins, M.B.; Griffin, E.B.; Dorsey, J.G.

    1977-10-01

    Methods have been developed for the preparation of various materials for spark source mass spectrography. The essential features of these preparations (all which can provide adequate precision in a cost-effective manner) consist in obtaining spark-stable electrode sample pieces, a common matrix, a reduction of anomolous effects in the spark, the incorporation of a suitable internal standard for plate response normalization, and a reduction in time

  16. Present status of NMCC and sample preparation method for bio-samples

    International Nuclear Information System (INIS)

    Futatsugawa, S.; Hatakeyama, S.; Saitou, S.; Sera, K.

    1993-01-01

    In NMCC(Nishina Memorial Cyclotron Center) we are doing researches on PET of nuclear medicine (Positron Emission Computed Tomography) and PIXE analysis (Particle Induced X-ray Emission) using a small cyclotron of compactly designed. The NMCC facilities have been opened to researchers of other institutions since April 1993. The present status of NMCC is described. Bio-samples (medical samples, plants, animals and environmental samples) have mainly been analyzed by PIXE in NMCC. Small amounts of bio-samples for PIXE are decomposed quickly and easily in a sealed PTFE (polytetrafluoroethylene) vessel with a microwave oven. This sample preparation method of bio-samples also is described. (author)

  17. Finding even more anthropogenic indicators in mildly prepared sediment samples

    DEFF Research Database (Denmark)

    Enevold, Renée; Odgaard, Bent Vad

    2016-01-01

    be worth the effort to prepare the NPP samples with as mild a preparation method as possible. We have mildly prepared NPP samples from a small forest hollow, Tårup Lund, Denmark. From the recovered NPP assemblages we attempt identifying anthropogenic indicators by comparing to the environmental information......NPPs in anthropogenic soils and archaeological samples are often numerous in types as well as in abundance. Preparing these soil samples with methods based on acid digestion holds the potential of severe bias leaving the NPP assemblages devoid of acid vulnerable NPPs. In many cases it might...... derived from sediment, pollen and macrofossil analyses. The sediment from the forest hollow encompasses environmental information from the last 6000 years, including a period of locally intense pastoral and/or agricultural activity during the Iron Age. Keywords: NPP diversity, forest hollow, anthropogenic...

  18. Recommended procedures for performance testing of radiobioassay laboratories: Volume 2, In vitro samples

    International Nuclear Information System (INIS)

    Fenrick, H.W.; MacLellan, J.A.

    1988-11-01

    Draft American National Standards Institute (ANSI) Standard N13.30 (Performance Criteria for Radiobioassay) was developed for the US Department of Energy and the US Nuclear Regulatory Commission to help ensure that bioassay laboratories provide accurate and consistent results. The draft standard specifies the criteria for defining the procedures necessary to establish a bioassay performance-testing laboratory and program. The bioassay testing laboratory will conduct tests to evaluate the performance of service laboratories. Pacific Northwest Laboratory helped develop testing procedures as part of an effort to evaluate the performance criteria by testing the existing measurement capabilities of various bioassay laboratories. This report recommends guidelines for the preparation, handling, storage, distribution, shipping, and documentation of in vitro test samples (artificial urine and fecal matter) for indirect bioassay. The data base and recommended records system for documenting radiobioassay performance at the service laboratories are also presented. 8 refs., 3 tabs

  19. Improved Procedure for Preparation of Covalently Bonded Cellulose Tris-phenylcarbamate Chiral Stationary Phases

    Institute of Scientific and Technical Information of China (English)

    秦峰; 陈小明; 刘月启; 邹汉法; 王俊德

    2005-01-01

    The classical method for preparation of covalently boned cellulose derivative chiral stationary phases (CSP) with diisocyanate as spacer was improved. Diisocyanate was firstly allowed to react with 3-aminopropyltriethoxysilane, and the resulting product was then applied as the spacer reagent to immobilize cellulose derivatives onto silica gel. Influences of the amount and the length of the spacer on the optical resolution ability of the CSP were investigated. Comparing improved procedure to classical diisocyanate method, the cross-linking between the glucose units of the cellulose derivatives was avoided to the most extent. With the improved procedure, regio-nonselective ways could be adooted to prepare covalently bonded CSP, which showed an advantage for the rapid preparation.

  20. Comparison of Three Sample Preparation Procedures for the Quantification of L-Arginine, Asymmetric Dimethylarginine, and Symmetric Dimethylarginine in Human Plasma Using HPLC-FLD

    Science.gov (United States)

    Schou-Pedersen, Anne Marie Voigt

    2018-01-01

    Increased asymmetric dimethylarginine (ADMA) in human plasma has been associated with reduced generation of nitric oxide, leading to atherosclerotic diseases. ADMA may therefore be an important biomarker for cardiovascular disease. In the present study, three sample preparation techniques were compared regarding the quantification of L-arginine and ADMA in human plasma: (A) protein precipitation (PP) based on aqueous trichloroacetic acid (TCA), (B) PP using a mixture of ammonia and acetonitrile, and (C) solid-phase extraction (SPE). The samples were analysed by using high-performance liquid chromatography with fluorescence detection (HPLC-FLD). The analytical performance of (A) was comparable with that of (C), demonstrating recoveries of >90%, coefficient of variations (CVs, %) of 0.994), precision (sample preparation of human plasma samples before HPLC-FLD in providing important information regarding elevated ADMA concentrations. PMID:29484214

  1. Influences of different sample preparation methods on tooth enamel ESR signals

    International Nuclear Information System (INIS)

    Zhang Wenyi; Jiao Ling; Zhang Liang'an; Pan Zhihong; Zeng Hongyu

    2005-01-01

    Objective: To study the influences of different sample preparation methods on tooth enamel ESR signals in order to reduce the effect of dentine on their sensitivities to radiation. Methods: The enamel was separated from dentine of non-irradiated adult teeth by mechanical, chemical, or both methods. The samples of different preparations were scanned by an ESR spectrometer before and after irradiation. Results: The response of ESR signals of samples prepared with different methods to radiation dose was significantly different. Conclusion: The selection of sample preparation method is very important for dose reconstruction by tooth enamel ESR dosimetry, especially in the low dose range. (authors)

  2. Global metabolite analysis of yeast: evaluation of sample preparation methods

    DEFF Research Database (Denmark)

    Villas-Bôas, Silas Granato; Højer-Pedersen, Jesper; Åkesson, Mats Fredrik

    2005-01-01

    Sample preparation is considered one of the limiting steps in microbial metabolome analysis. Eukaryotes and prokaryotes behave very differently during the several steps of classical sample preparation methods for analysis of metabolites. Even within the eukaryote kingdom there is a vast diversity...

  3. Fluidics platform and method for sample preparation and analysis

    Science.gov (United States)

    Benner, W. Henry; Dzenitis, John M.; Bennet, William J.; Baker, Brian R.

    2014-08-19

    Herein provided are fluidics platform and method for sample preparation and analysis. The fluidics platform is capable of analyzing DNA from blood samples using amplification assays such as polymerase-chain-reaction assays and loop-mediated-isothermal-amplification assays. The fluidics platform can also be used for other types of assays and analyzes. In some embodiments, a sample in a sealed tube can be inserted directly. The following isolation, detection, and analyzes can be performed without a user's intervention. The disclosed platform may also comprises a sample preparation system with a magnetic actuator, a heater, and an air-drying mechanism, and fluid manipulation processes for extraction, washing, elution, assay assembly, assay detection, and cleaning after reactions and between samples.

  4. Preparation and Loading Process of Single Crystalline Samples into a Gas Environmental Cell Holder for In Situ Atomic Resolution Scanning Transmission Electron Microscopic Observation.

    Science.gov (United States)

    Straubinger, Rainer; Beyer, Andreas; Volz, Kerstin

    2016-06-01

    A reproducible way to transfer a single crystalline sample into a gas environmental cell holder for in situ transmission electron microscopic (TEM) analysis is shown in this study. As in situ holders have only single-tilt capability, it is necessary to prepare the sample precisely along a specific zone axis. This can be achieved by a very accurate focused ion beam lift-out preparation. We show a step-by-step procedure to prepare the sample and transfer it into the gas environmental cell. The sample material is a GaP/Ga(NAsP)/GaP multi-quantum well structure on Si. Scanning TEM observations prove that it is possible to achieve atomic resolution at very high temperatures in a nitrogen environment of 100,000 Pa.

  5. Combining Electrochemical Sensors with Miniaturized Sample Preparation for Rapid Detection in Clinical Samples

    Science.gov (United States)

    Bunyakul, Natinan; Baeumner, Antje J.

    2015-01-01

    Clinical analyses benefit world-wide from rapid and reliable diagnostics tests. New tests are sought with greatest demand not only for new analytes, but also to reduce costs, complexity and lengthy analysis times of current techniques. Among the myriad of possibilities available today to develop new test systems, amperometric biosensors are prominent players—best represented by the ubiquitous amperometric-based glucose sensors. Electrochemical approaches in general require little and often enough only simple hardware components, are rugged and yet provide low limits of detection. They thus offer many of the desirable attributes for point-of-care/point-of-need tests. This review focuses on investigating the important integration of sample preparation with (primarily electrochemical) biosensors. Sample clean up requirements, miniaturized sample preparation strategies, and their potential integration with sensors will be discussed, focusing on clinical sample analyses. PMID:25558994

  6. Sample preparation techniques in trace element analysis by X-ray emission spectroscopy

    International Nuclear Information System (INIS)

    Valkovic, V.

    1983-11-01

    The report, written under a research contract with the IAEA, contains a detailed presentation of the most difficult problem encountered in the trace element analysis by methods of the X-ray emission spectroscopy, namely the sample preparation techniques. The following items are covered. Sampling - with specific consideration of aerosols, water, soil, biological materials, petroleum and its products, storage of samples and their handling. Pretreatment of samples - preconcentration, ashing, solvent extraction, ion exchange and electrodeposition. Sample preparations for PIXE - analysis - backings, target uniformity and homogeneity, effects of irradiation, internal standards and specific examples of preparation (aqueous, biological, blood serum and solid samples). Sample preparations for radioactive sources or tube excitation - with specific examples (water, liquid and solid samples, soil, geological, plants and tissue samples). Finally, the problem of standards and reference materials, as well as that of interlaboratory comparisons, is discussed

  7. Sample Preparation for Mass Spectrometry Imaging of Plant Tissues: A Review

    Science.gov (United States)

    Dong, Yonghui; Li, Bin; Malitsky, Sergey; Rogachev, Ilana; Aharoni, Asaph; Kaftan, Filip; Svatoš, Aleš; Franceschi, Pietro

    2016-01-01

    Mass spectrometry imaging (MSI) is a mass spectrometry based molecular ion imaging technique. It provides the means for ascertaining the spatial distribution of a large variety of analytes directly on tissue sample surfaces without any labeling or staining agents. These advantages make it an attractive molecular histology tool in medical, pharmaceutical, and biological research. Likewise, MSI has started gaining popularity in plant sciences; yet, information regarding sample preparation methods for plant tissues is still limited. Sample preparation is a crucial step that is directly associated with the quality and authenticity of the imaging results, it therefore demands in-depth studies based on the characteristics of plant samples. In this review, a sample preparation pipeline is discussed in detail and illustrated through selected practical examples. In particular, special concerns regarding sample preparation for plant imaging are critically evaluated. Finally, the applications of MSI techniques in plants are reviewed according to different classes of plant metabolites. PMID:26904042

  8. Sample Preparation for Mass Spectrometry Imaging of Plant Tissues: A Review.

    Science.gov (United States)

    Dong, Yonghui; Li, Bin; Malitsky, Sergey; Rogachev, Ilana; Aharoni, Asaph; Kaftan, Filip; Svatoš, Aleš; Franceschi, Pietro

    2016-01-01

    Mass spectrometry imaging (MSI) is a mass spectrometry based molecular ion imaging technique. It provides the means for ascertaining the spatial distribution of a large variety of analytes directly on tissue sample surfaces without any labeling or staining agents. These advantages make it an attractive molecular histology tool in medical, pharmaceutical, and biological research. Likewise, MSI has started gaining popularity in plant sciences; yet, information regarding sample preparation methods for plant tissues is still limited. Sample preparation is a crucial step that is directly associated with the quality and authenticity of the imaging results, it therefore demands in-depth studies based on the characteristics of plant samples. In this review, a sample preparation pipeline is discussed in detail and illustrated through selected practical examples. In particular, special concerns regarding sample preparation for plant imaging are critically evaluated. Finally, the applications of MSI techniques in plants are reviewed according to different classes of plant metabolites.

  9. 15N sample preparation for mass spectroscopy analysis

    International Nuclear Information System (INIS)

    Trivelin, P.C.O.; Salati, E.; Matsui, E.

    1973-01-01

    Technics for preparing 15 N samples to be analised is presented. Dumas method and oxidation by sodium hypobromite method are described in order to get the appropriate sample. Method to calculate 15 N ratio from mass spectrometry dates is also discussed [pt

  10. Preparation of archaeological samples for its dating by thermoluminescence

    International Nuclear Information System (INIS)

    Mejia F, D.

    2000-01-01

    The present work shows the results of the preparation of archaeological samples for their dating by thermoluminescence (Tl) using the Fine grain technique established by Zimmerman but with the varying of such preparation was realized in normal daylight conditions, only the taking of the Tl readings were realized in dark room and red light. In the chapter 1 basic concepts are described about: matter constitution, radioactivity, units and radiation magnitudes, and thermoluminescence. In the chapter 2 some theoretical aspects on dating are showed. It is described how realizing the samples collection, the fine grain method, the determination of the accumulated dose through the years or paleodoses (P=Q+I) by mean of the increasing to obtain the dose equivalent dose (Q) and the signal regeneration method to obtain the correction factor by supra linearity (1), the determination of the annual dose rate to apply the age equation and the evaluation of the age uncertainty with the error limits. The development of experimental part with samples from the archaeological site named Edzna in Campeche, Mexico is described in the chapter 3. The results are presented in the chapter 4. It was obtained an age for the sample named CH7 it was obtained an age of 389 ± years. In conclusion the preparation of the archaeological samples for their dating by Tl in the conditions before mentioned is reliable, but they must be realized more studies with samples of well known age, preparing them in normal daylight conditions and simultaneously in dark room with red light. In order to observe how respond the minerals present in the sample at different dose rapidity, the same samples must be radiated with radiation sources with different dose rate. (Author)

  11. Benchmarking sample preparation/digestion protocols reveals tube-gel being a fast and repeatable method for quantitative proteomics.

    Science.gov (United States)

    Muller, Leslie; Fornecker, Luc; Van Dorsselaer, Alain; Cianférani, Sarah; Carapito, Christine

    2016-12-01

    Sample preparation, typically by in-solution or in-gel approaches, has a strong influence on the accuracy and robustness of quantitative proteomics workflows. The major benefit of in-gel procedures is their compatibility with detergents (such as SDS) for protein solubilization. However, SDS-PAGE is a time-consuming approach. Tube-gel (TG) preparation circumvents this drawback as it involves directly trapping the sample in a polyacrylamide gel matrix without electrophoresis. We report here the first global label-free quantitative comparison between TG, stacking gel (SG), and basic liquid digestion (LD). A series of UPS1 standard mixtures (at 0.5, 1, 2.5, 5, 10, and 25 fmol) were spiked in a complex yeast lysate background. TG preparation allowed more yeast proteins to be identified than did the SG and LD approaches, with mean numbers of 1979, 1788, and 1323 proteins identified, respectively. Furthermore, the TG method proved equivalent to SG and superior to LD in terms of the repeatability of the subsequent experiments, with mean CV for yeast protein label-free quantifications of 7, 9, and 10%. Finally, known variant UPS1 proteins were successfully detected in the TG-prepared sample within a complex background with high sensitivity. All the data from this study are accessible on ProteomeXchange (PXD003841). © 2016 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Sample preparation and EFTEM of Meat Samples for Nanoparticle Analysis in Food

    International Nuclear Information System (INIS)

    Lari, L; Dudkiewicz, A

    2014-01-01

    Nanoparticles are used in industry for personal care products and the preparation of food. In the latter application, their functions include the prevention of microbes' growth, increase of the foods nutritional value and sensory quality. EU regulations require a risk assessment of the nanoparticles used in foods and food contact materials before the products can reach the market. However, availability of validated analytical methodologies for detection and characterisation of the nanoparticles in food hampers appropriate risk assessment. As part of a research on the evaluation of the methods for screening and quantification of Ag nanoparticles in meat we have tested a new TEM sample preparation alternative to resin embedding and cryo-sectioning. Energy filtered TEM analysis was applied to evaluate thickness and the uniformity of thin meat layers acquired at increasing input of the sample demonstrating that the protocols used ensured good stability under the electron beam, reliable sample concentration and reproducibility

  13. Sample preparation and EFTEM of Meat Samples for Nanoparticle Analysis in Food

    Science.gov (United States)

    Lari, L.; Dudkiewicz, A.

    2014-06-01

    Nanoparticles are used in industry for personal care products and the preparation of food. In the latter application, their functions include the prevention of microbes' growth, increase of the foods nutritional value and sensory quality. EU regulations require a risk assessment of the nanoparticles used in foods and food contact materials before the products can reach the market. However, availability of validated analytical methodologies for detection and characterisation of the nanoparticles in food hampers appropriate risk assessment. As part of a research on the evaluation of the methods for screening and quantification of Ag nanoparticles in meat we have tested a new TEM sample preparation alternative to resin embedding and cryo-sectioning. Energy filtered TEM analysis was applied to evaluate thickness and the uniformity of thin meat layers acquired at increasing input of the sample demonstrating that the protocols used ensured good stability under the electron beam, reliable sample concentration and reproducibility.

  14. Guidelines for the preparation of emergency operating procedures. Resolution of comments on NUREG-0799

    International Nuclear Information System (INIS)

    1982-08-01

    The purpose of this document is to identify the elements necessary for utilities to prepare and implement a program of Emergency Operating Procedures (EOPs) for use by control room personnel to assist in mitigating the consequences of a broad range of accidents and multiple equipment failures. This document applies only to the EOPs so designated; it does not address emergency preparedness or emergency planning. It also represents the resolution of comments on NUREG-0799, Draft Criteria for Preparation of Emergency Operating Procedures

  15. Assessment of different sample preparation routes for mass spectrometric monitoring and imaging of lipids in bone cells via ToF-SIMS

    Science.gov (United States)

    Schaepe, Kaija; Kokesch-Himmelreich, Julia; Rohnke, Marcus; Wagner, Alena-Svenja; Schaaf, Thimo; Wenisch, Sabine; Janek, Jürgen

    2015-01-01

    In ToF-SIMS analysis, the experimental outcome from cell experiments is to a great extent influenced by the sample preparation routine. In order to better judge this critical influence in the case of lipid analysis, a detailed comparison of different sample preparation routines is performed—aiming at an optimized preparation routine for systematic lipid imaging of cell cultures. For this purpose, human mesenchymal stem cells were analyzed: (a) as chemically fixed, (b) freeze-dried, and (c) frozen-hydrated. For chemical fixation, different fixatives, i.e., glutaraldehyde, paraformaldehyde, and a mixture of both, were tested with different postfixative handling procedures like storage in phosphate buffered saline, water or critical point drying. Furthermore, secondary lipid fixation via osmium tetroxide was taken into account and the effect of an ascending alcohol series with and without this secondary lipid fixation was evaluated. Concerning freeze-drying, three different postprocessing possibilities were examined. One can be considered as a pure cryofixation technique while the other two routes were based on chemical fixation. Cryofixation methods known from literature, i.e., freeze-fracturing and simple frozen-hydrated preparation, were also evaluated to complete the comparison of sample preparation techniques. Subsequent data evaluation of SIMS spectra in both, positive and negative, ion mode was performed via principal component analysis by use of peak sets representative for lipids. For freeze-fracturing, these experiments revealed poor reproducibility making this preparation route unsuitable for systematic investigations and statistic data evaluation. Freeze-drying after cryofixation showed improved reproducibility and well preserved lipid contents while the other freeze-drying procedures showed drawbacks in one of these criteria. In comparison, chemical fixation techniques via glutar- and/or paraformaldehyde proved most suitable in terms of reproducibility

  16. Sample preparation for liquid chromatographic analysis of phytochemicals in biological fluids.

    Science.gov (United States)

    Oh, Ju-Hee; Lee, Young-Joo

    2014-01-01

    Natural products have been used traditionally for the treatment and prevention of diseases for thousands of years and are nowadays consumed as dietary supplements and herbal medicine. To ensure the safe and effective use of these herbal products, information about bioavailability of active compounds in plasma or target tissues should be provided via validated analytical methods combined with appropriate sampling methods. To provide comprehensive and abridged information about sample preparation methods for the quantification of phytochemicals in biological samples using liquid chromatography analysis. Sample pre-treatment procedures used in analytical methods for in vivo pharmacokinetic studies of natural compounds or herbal medicines were reviewed. These were categorised according to the biological matrices (plasma, bile, urine, faeces and tissues) and sample clean-up processes (protein precipitation, liquid-liquid extraction and solid-phase extraction). Although various kinds of sample pre-treatment methods have been developed, liquid-liquid extraction is still widely used and solid-phase extraction is becoming increasingly popular because of its efficiency for extensive clean up of complex matrix samples. However, protein precipitation is still favoured due to its simplicity. Sample treatment for phytochemical analysis in biological fluids is an indispensable and critical step to obtain high quality results. This step could dominate the overall analytical process because both the duration of the process as well as the reliability of the data depend in large part on its efficiency. Thus, special attention should be given to the choice of a proper sample treatment method that targets analytes and their biomatrix. Copyright © 2013 John Wiley & Sons, Ltd.

  17. Sample preparation composite and replicate strategy for assay of solid oral drug products.

    Science.gov (United States)

    Harrington, Brent; Nickerson, Beverly; Guo, Michele Xuemei; Barber, Marc; Giamalva, David; Lee, Carlos; Scrivens, Garry

    2014-12-16

    In pharmaceutical analysis, the results of drug product assay testing are used to make decisions regarding the quality, efficacy, and stability of the drug product. In order to make sound risk-based decisions concerning drug product potency, an understanding of the uncertainty of the reportable assay value is required. Utilizing the most restrictive criteria in current regulatory documentation, a maximum variability attributed to method repeatability is defined for a drug product potency assay. A sampling strategy that reduces the repeatability component of the assay variability below this predefined maximum is demonstrated. The sampling strategy consists of determining the number of dosage units (k) to be prepared in a composite sample of which there may be a number of equivalent replicate (r) sample preparations. The variability, as measured by the standard error (SE), of a potency assay consists of several sources such as sample preparation and dosage unit variability. A sampling scheme that increases the number of sample preparations (r) and/or number of dosage units (k) per sample preparation will reduce the assay variability and thus decrease the uncertainty around decisions made concerning the potency of the drug product. A maximum allowable repeatability component of the standard error (SE) for the potency assay is derived using material in current regulatory documents. A table of solutions for the number of dosage units per sample preparation (r) and number of replicate sample preparations (k) is presented for any ratio of sample preparation and dosage unit variability.

  18. The beauty of being (label)-free: sample preparation methods for SWATH-MS and next-generation targeted proteomics

    Science.gov (United States)

    Campbell, Kate; Deery, Michael J.; Lilley, Kathryn S.; Ralser, Markus

    2014-01-01

    The combination of qualitative analysis with label-free quantification has greatly facilitated the throughput and flexibility of novel proteomic techniques. However, such methods rely heavily on robust and reproducible sample preparation procedures. Here, we benchmark a selection of in gel, on filter, and in solution digestion workflows for their application in label-free proteomics. Each procedure was associated with differing advantages and disadvantages. The in gel methods interrogated were cost effective, but were limited in throughput and digest efficiency. Filter-aided sample preparations facilitated reasonable processing times and yielded a balanced representation of membrane proteins, but led to a high signal variation in quantification experiments. Two in solution digest protocols, however, gave optimal performance for label-free proteomics. A protocol based on the detergent RapiGest led to the highest number of detected proteins at second-best signal stability, while a protocol based on acetonitrile-digestion, RapidACN, scored best in throughput and signal stability but came second in protein identification. In addition, we compared label-free data dependent (DDA) and data independent (SWATH) acquisition on a TripleTOF 5600 instrument. While largely similar in protein detection, SWATH outperformed DDA in quantification, reducing signal variation and markedly increasing the number of precisely quantified peptides. PMID:24741437

  19. Acceptance test procedure for core sample trucks

    International Nuclear Information System (INIS)

    Smalley, J.L.

    1995-01-01

    The purpose of this Acceptance Test Procedure is to provide instruction and documentation for acceptance testing of the rotary mode core sample trucks, HO-68K-4600 and HO-68K-4647. The rotary mode core sample trucks were based upon the design of the second core sample truck (HO-68K-4345) which was constructed to implement rotary mode sampling of the waste tanks at Hanford. Acceptance testing of the rotary mode core sample trucks will verify that the design requirements have been met. All testing will be non-radioactive and stand-in materials shall be used to simulate waste tank conditions. Compressed air will be substituted for nitrogen during the majority of testing, with nitrogen being used only for flow characterization

  20. Sample preparation optimization in fecal metabolic profiling.

    Science.gov (United States)

    Deda, Olga; Chatziioannou, Anastasia Chrysovalantou; Fasoula, Stella; Palachanis, Dimitris; Raikos, Νicolaos; Theodoridis, Georgios A; Gika, Helen G

    2017-03-15

    Metabolomic analysis of feces can provide useful insight on the metabolic status, the health/disease state of the human/animal and the symbiosis with the gut microbiome. As a result, recently there is increased interest on the application of holistic analysis of feces for biomarker discovery. For metabolomics applications, the sample preparation process used prior to the analysis of fecal samples is of high importance, as it greatly affects the obtained metabolic profile, especially since feces, as matrix are diversifying in their physicochemical characteristics and molecular content. However there is still little information in the literature and lack of a universal approach on sample treatment for fecal metabolic profiling. The scope of the present work was to study the conditions for sample preparation of rat feces with the ultimate goal of the acquisition of comprehensive metabolic profiles either untargeted by NMR spectroscopy and GC-MS or targeted by HILIC-MS/MS. A fecal sample pooled from male and female Wistar rats was extracted under various conditions by modifying the pH value, the nature of the organic solvent and the sample weight to solvent volume ratio. It was found that the 1/2 (w f /v s ) ratio provided the highest number of metabolites under neutral and basic conditions in both untargeted profiling techniques. Concerning LC-MS profiles, neutral acetonitrile and propanol provided higher signals and wide metabolite coverage, though extraction efficiency is metabolite dependent. Copyright © 2016 Elsevier B.V. All rights reserved.

  1. Secondary School Students' Reasoning about Conditional Probability, Samples, and Sampling Procedures

    Science.gov (United States)

    Prodromou, Theodosia

    2016-01-01

    In the Australian mathematics curriculum, Year 12 students (aged 16-17) are asked to solve conditional probability problems that involve the representation of the problem situation with two-way tables or three-dimensional diagrams and consider sampling procedures that result in different correct answers. In a small exploratory study, we…

  2. Field Sample Preparation Method Development for Isotope Ratio Mass Spectrometry

    International Nuclear Information System (INIS)

    Leibman, C.; Weisbrod, K.; Yoshida, T.

    2015-01-01

    Non-proliferation and International Security (NA-241) established a working group of researchers from Los Alamos National Laboratory (LANL), Pacific Northwest National Laboratory (PNNL) and Savannah River National Laboratory (SRNL) to evaluate the utilization of in-field mass spectrometry for safeguards applications. The survey of commercial off-the-shelf (COTS) mass spectrometers (MS) revealed no instrumentation existed capable of meeting all the potential safeguards requirements for performance, portability, and ease of use. Additionally, fieldable instruments are unlikely to meet the International Target Values (ITVs) for accuracy and precision for isotope ratio measurements achieved with laboratory methods. The major gaps identified for in-field actinide isotope ratio analysis were in the areas of: 1. sample preparation and/or sample introduction, 2. size reduction of mass analyzers and ionization sources, 3. system automation, and 4. decreased system cost. Development work in 2 through 4, numerated above continues, in the private and public sector. LANL is focusing on developing sample preparation/sample introduction methods for use with the different sample types anticipated for safeguard applications. Addressing sample handling and sample preparation methods for MS analysis will enable use of new MS instrumentation as it becomes commercially available. As one example, we have developed a rapid, sample preparation method for dissolution of uranium and plutonium oxides using ammonium bifluoride (ABF). ABF is a significantly safer and faster alternative to digestion with boiling combinations of highly concentrated mineral acids. Actinides digested with ABF yield fluorides, which can then be analyzed directly or chemically converted and separated using established column chromatography techniques as needed prior to isotope analysis. The reagent volumes and the sample processing steps associated with ABF sample digestion lend themselves to automation and field

  3. Solvent-free sample preparation by headspace solid-phase microextraction applied to the tracing of n-butyl nitrite abuse.

    Science.gov (United States)

    Tytgat, J; Daenens, P

    1996-01-01

    The most common alkyl nitrites encountered in forensic toxicology are iso-butyl, n-butyl and iso-pentyl(amyl) nitrites. All have become popular as an aphrodisiac, especially among the homosexual population. Alkyl nitrites are a volatile and unstable group of compounds, which hydrolyse in aqueous matrices to the alcohol and nitrite ion. Here we describe a fast, clean and sensitive procedure for the detection of hydrolysed n-butyl nitrite in whole human blood using a new, solvent-free sampling technique, the headspace solid-phase micro-extraction (HSPME), combined with GC/FID analysis. Sample preparation was investigated using two different stationary phases (100 microns polydimethylsiloxane and 85 microns polyacrylate), coating a fused silica fibre. The effect of different sampling times at fixed temperatures was also studied. Our results demonstrate that the HSPME/GC/FID procedure allows tracing of n-butyl nitrite abuse and detects hydrolysed n-butyl nitrite, i.e., released n-butanol, in whole blood at the 1 ng/mL level.

  4. Choice and preparation of standard samples for X-ray spectral microanalysis

    International Nuclear Information System (INIS)

    Gavrilenko, I.S.; Surzhko, V.F.

    1989-01-01

    Choice, preparation and certification of standard samples for X-ray spectral microanalysis are considered. Requirements for standard samples in terms of concentration and volume, porosity, corrosion, conductivity distribution are formulated. Stages of sample preparation process, including composition choice, heat treatment, section production, certification, are considered in detail. The choice of composition is based on studying phase equilibrium diagrams, subdivided into 6 types

  5. Lights Will Guide You : Sample Preparation and Applications for Integrated Laser and Electron Microscopy

    Science.gov (United States)

    Karreman, M. A.

    2013-03-01

    Correlative microscopy is the combined use of two different forms of microscopy in the study of a specimen, allowing for the exploitation of the advantages of both imaging tools. The integrated Laser and Electron Microscope (iLEM), developed at Utrecht University, combines a fluorescence microscope (FM) and a transmission electron microscope (TEM) in a single set-up. The region of interest in the specimen is labeled or tagged with a fluorescent probe and can easily be identified within a large field of view with the FM. Next, this same area is retraced in the TEM and can be studied at high resolution. The iLEM demands samples that can be imaged with both FM and TEM. Biological specimen, typically composed of light elements, generate low image contrast in the TEM. Therefore, these samples are often ‘contrasted’ with heavy metal stains. FM, on the other hand, images fluorescent samples. Sample preparation for correlative microscopy, and iLEM in particular, is complicated by the fact that the heavy metals stains employed for TEM quench the fluorescent signal of the probe that is imaged with FM. The first part of this thesis outlines preparation procedures for biological material yielding specimen that can be imaged with the iLEM. Here, approaches for the contrasting of thin sections of cells and tissue are introduced that do not affect the fluorescence signal of the probe that marks the region of interest. Furthermore, two novel procedures, VIS2FIXH and VIS2FIX­FS are described that allow for the chemical fixation of thin sections of cryo-immobilized material. These procedures greatly expedite the sample preparation process, and open up novel possibilities for the immuno-labeling of difficult antigens, eg. proteins and lipids that are challenging to preserve. The second part of this thesis describes applications of iLEM in research in the field of life and material science. The iLEM was employed in the study of UVC induced apoptosis (programmed cell death) of

  6. Inverse sampled Bernoulli (ISB) procedure for estimating a population proportion, with nuclear material applications

    International Nuclear Information System (INIS)

    Wright, T.

    1982-01-01

    A new sampling procedure is introduced for estimating a population proportion. The procedure combines the ideas of inverse binomial sampling and Bernoulli sampling. An unbiased estimator is given with its variance. The procedure can be viewed as a generalization of inverse binomial sampling

  7. Novel strategies for sample preparation in forensic toxicology.

    Science.gov (United States)

    Samanidou, Victoria; Kovatsi, Leda; Fragou, Domniki; Rentifis, Konstantinos

    2011-09-01

    This paper provides a review of novel strategies for sample preparation in forensic toxicology. The review initially outlines the principle of each technique, followed by sections addressing each class of abused drugs separately. The novel strategies currently reviewed focus on the preparation of various biological samples for the subsequent determination of opiates, benzodiazepines, amphetamines, cocaine, hallucinogens, tricyclic antidepressants, antipsychotics and cannabinoids. According to our experience, these analytes are the most frequently responsible for intoxications in Greece. The applications of techniques such as disposable pipette extraction, microextraction by packed sorbent, matrix solid-phase dispersion, solid-phase microextraction, polymer monolith microextraction, stir bar sorptive extraction and others, which are rapidly gaining acceptance in the field of toxicology, are currently reviewed.

  8. Sample Preparation Methodologies for In Situ Liquid and Gaseous Cell Analytical Transmission Electron Microscopy of Electropolished Specimens.

    Science.gov (United States)

    Zhong, Xiang Li; Schilling, Sibylle; Zaluzec, Nestor J; Burke, M Grace

    2016-12-01

    In recent years, an increasing number of studies utilizing in situ liquid and/or gaseous cell scanning/transmission electron microscopy (S/TEM) have been reported. Because of the difficulty in the preparation of suitable specimens, these environmental S/TEM studies have been generally limited to studies of nanoscale structured materials such as nanoparticles, nanowires, or sputtered thin films. In this paper, we present two methodologies which have been developed to facilitate the preparation of electron-transparent samples from conventional bulk metals and alloys for in situ liquid/gaseous cell S/TEM experiments. These methods take advantage of combining sequential electrochemical jet polishing followed by focused ion beam extraction techniques to create large electron-transparent areas for site-specific observation. As an example, we illustrate the application of this methodology for the preparation of in situ specimens from a cold-rolled Type 304 austenitic stainless steel sample, which was subsequently examined in both 1 atm of air as well as fully immersed in a H2O environment in the S/TEM followed by hyperspectral imaging. These preparation techniques can be successfully applied as a general procedure for a wide range of metals and alloys, and are suitable for a variety of in situ analytical S/TEM studies in both aqueous and gaseous environments.

  9. Supporting Sampling and Sample Preparation Tools for Isotope and Nuclear Analysis

    International Nuclear Information System (INIS)

    2016-03-01

    Nuclear and related techniques can help develop climate-smart agricultural practices by optimizing water and nutrient use efficiency, assessing organic carbon sequestration in soil, and assisting in the evaluation of soil erosion control measures. Knowledge on the behaviour of radioactive materials in soil, water and foodstuffs is also essential in enhancing nuclear emergency preparedness and response. Appropriate sampling and sample preparation are the first steps to ensure the quality and effective use of the measurements and this publication provides comprehensive detail on the necessary steps

  10. Procedure for determination of alpha emitters in urine and dregs samples

    International Nuclear Information System (INIS)

    Serdeiro, Nelida H.

    2005-01-01

    The purpose of this work is to establish the procedure for the identification and quantification of emitting alpha radionuclides in urine and dregs samples. This procedure are applied to all laboratories of the countries of the Project ARCAL LXXVII that determinate alpha emitting radionuclides in biological samples for biological assessment [es

  11. Development of sample preparation method for honey analysis using PIXE

    International Nuclear Information System (INIS)

    Saitoh, Katsumi; Chiba, Keiko; Sera, Koichiro

    2008-01-01

    We developed an original preparation method for honey samples (samples in paste-like state) specifically designed for PIXE analysis. The results of PIXE analysis of thin targets prepared by adding a standard containing nine elements to honey samples demonstrated that the preparation method bestowed sufficient accuracy on quantitative values. PIXE analysis of 13 kinds of honey was performed, and eight mineral components (Si, P, S, K, Ca, Mn, Cu and Zn) were detected in all honey samples. The principal mineral components were K and Ca, and the quantitative value for K accounted for the majority of the total value for mineral components. K content in honey varies greatly depending on the plant source. Chestnuts had the highest K content. In fact, it was 2-3 times that of Manuka, which is known as a high quality honey. K content of false-acacia, which is produced in the greatest abundance, was 1/20 that of chestnuts. (author)

  12. Analytical Chemistry Laboratory (ACL) procedure compendium

    International Nuclear Information System (INIS)

    1993-01-01

    This volume contains the interim change notice for sample preparation methods. Covered are: acid digestion for metals analysis, fusion of Hanford tank waste solids, water leach of sludges/soils/other solids, extraction procedure toxicity (simulate leach in landfill), sample preparation for gamma spectroscopy, acid digestion for radiochemical analysis, leach preparation of solids for free cyanide analysis, aqueous leach of solids for anion analysis, microwave digestion of glasses and slurries for ICP/MS, toxicity characteristic leaching extraction for inorganics, leach/dissolution of activated metal for radiochemical analysis, extraction of single-shell tank (SST) samples for semi-VOC analysis, preparation and cleanup of hydrocarbon- containing samples for VOC and semi-VOC analysis, receiving of waste tank samples in onsite transfer cask, receipt and inspection of SST samples, receipt and extrusion of core samples at 325A shielded facility, cleaning and shipping of waste tank samplers, homogenization of solutions/slurries/sludges, and test sample preparation for bioassay quality control program

  13. Sample preparation method for scanning force microscopy

    CERN Document Server

    Jankov, I R; Szente, R N; Carreno, M N P; Swart, J W; Landers, R

    2001-01-01

    We present a method of sample preparation for studies of ion implantation on metal surfaces. The method, employing a mechanical mask, is specially adapted for samples analysed by Scanning Force Microscopy. It was successfully tested on polycrystalline copper substrates implanted with phosphorus ions at an acceleration voltage of 39 keV. The changes of the electrical properties of the surface were measured by Kelvin Probe Force Microscopy and the surface composition was analysed by Auger Electron Spectroscopy.

  14. Status report of AMS sample preparation laboratory at GADAM Centre, Gliwice, Poland

    Energy Technology Data Exchange (ETDEWEB)

    Piotrowska, N., E-mail: natalia.piotrowska@polsl.pl [GADAM Centre of Excellence, Department of Radioisotopes, Institute of Physics, Silesian University of Technology, Gliwice (Poland)

    2013-01-15

    The laboratory for {sup 14}C AMS sample preparation in the Gliwice Radiocarbon Laboratory has gradually evolved since its start in 1999 to cater for an increase in volume and variety of radiocarbon dating samples. To date, nearly 2000 graphite targets have been produced from materials such as plant macrofossils, charcoal, peat, bones, shells and wood. The equipment comprises a station for chemical preparation and high vacuum lines for production, purification and graphitization of sample carbon dioxide. The present capacity allows preparation of up to 400 targets annually for the needs of scientific projects and external orders for radiocarbon dating continuously received by the GADAM Centre of Excellence. The laboratory's sample preparation protocols and recent improvements are described and its performance during the 10 years of activity is discussed in terms of parameters obtained from reference materials prepared in this laboratory and demonstrated with a few science applications.

  15. Partial report and other sampling procedures overestimate the duration of iconic memory.

    Science.gov (United States)

    Appelman, I B

    1980-03-01

    In three experiments, subjects estimated the duration of a brief visual image (iconic memory) either directly by adjusting onset of a click to offset of the visual image, or indirectly with a Sperling partial report (sampling) procedure. The results indicated that partial report and other sampling procedures may reflect other brief phenomena along with iconic memory. First, the partial report procedure yields a greater estimate of the duration of iconic memory than the more direct click method. Second, the partial report estimate of the duration of iconic memory is affected if the subject is required to simultaneously retain a list of distractor items (memory load), while the click method estimate of the duration of iconic memory is not affected by a memory load. Finally, another sampling procedure based on visual cuing yields different estimates of the duration of iconic memory depending on how many items are cued. It was concluded that partial report and other sampling procedures overestimate the duration of iconic memory.

  16. Large-volume injection of sample diluents not miscible with the mobile phase as an alternative approach in sample preparation for bioanalysis: an application for fenspiride bioequivalence.

    Science.gov (United States)

    Medvedovici, Andrei; Udrescu, Stefan; Albu, Florin; Tache, Florentin; David, Victor

    2011-09-01

    Liquid-liquid extraction of target compounds from biological matrices followed by the injection of a large volume from the organic layer into the chromatographic column operated under reversed-phase (RP) conditions would successfully combine the selectivity and the straightforward character of the procedure in order to enhance sensitivity, compared with the usual approach of involving solvent evaporation and residue re-dissolution. Large-volume injection of samples in diluents that are not miscible with the mobile phase was recently introduced in chromatographic practice. The risk of random errors produced during the manipulation of samples is also substantially reduced. A bioanalytical method designed for the bioequivalence of fenspiride containing pharmaceutical formulations was based on a sample preparation procedure involving extraction of the target analyte and the internal standard (trimetazidine) from alkalinized plasma samples in 1-octanol. A volume of 75 µl from the octanol layer was directly injected on a Zorbax SB C18 Rapid Resolution, 50 mm length × 4.6 mm internal diameter × 1.8 µm particle size column, with the RP separation being carried out under gradient elution conditions. Detection was made through positive ESI and MS/MS. Aspects related to method development and validation are discussed. The bioanalytical method was successfully applied to assess bioequivalence of a modified release pharmaceutical formulation containing 80 mg fenspiride hydrochloride during two different studies carried out as single-dose administration under fasting and fed conditions (four arms), and multiple doses administration, respectively. The quality attributes assigned to the bioanalytical method, as resulting from its application to the bioequivalence studies, are highlighted and fully demonstrate that sample preparation based on large-volume injection of immiscible diluents has an increased potential for application in bioanalysis.

  17. Optimizing Frozen Sample Preparation for Laser Microdissection: Assessment of CryoJane Tape-Transfer System®.

    Directory of Open Access Journals (Sweden)

    Yelena G Golubeva

    Full Text Available Laser microdissection is an invaluable tool in medical research that facilitates collecting specific cell populations for molecular analysis. Diversity of research targets (e.g., cancerous and precancerous lesions in clinical and animal research, cell pellets, rodent embryos, etc. and varied scientific objectives, however, present challenges toward establishing standard laser microdissection protocols. Sample preparation is crucial for quality RNA, DNA and protein retrieval, where it often determines the feasibility of a laser microdissection project. The majority of microdissection studies in clinical and animal model research are conducted on frozen tissues containing native nucleic acids, unmodified by fixation. However, the variable morphological quality of frozen sections from tissues containing fat, collagen or delicate cell structures can limit or prevent successful harvest of the desired cell population via laser dissection. The CryoJane Tape-Transfer System®, a commercial device that improves cryosectioning outcomes on glass slides has been reported superior for slide preparation and isolation of high quality osteocyte RNA (frozen bone during laser dissection. Considering the reported advantages of CryoJane for laser dissection on glass slides, we asked whether the system could also work with the plastic membrane slides used by UV laser based microdissection instruments, as these are better suited for collection of larger target areas. In an attempt to optimize laser microdissection slide preparation for tissues of different RNA stability and cryosectioning difficulty, we evaluated the CryoJane system for use with both glass (laser capture microdissection and membrane (laser cutting microdissection slides. We have established a sample preparation protocol for glass and membrane slides including manual coating of membrane slides with CryoJane solutions, cryosectioning, slide staining and dissection procedure, lysis and RNA extraction

  18. Influence of sample preparation on the transformation of low-density to high-density amorphous ice: An explanation based on the potential energy landscape

    Science.gov (United States)

    Giovambattista, Nicolas; Starr, Francis W.; Poole, Peter H.

    2017-07-01

    Experiments and computer simulations of the transformations of amorphous ices display different behaviors depending on sample preparation methods and on the rates of change of temperature and pressure to which samples are subjected. In addition to these factors, simulation results also depend strongly on the chosen water model. Using computer simulations of the ST2 water model, we study how the sharpness of the compression-induced transition from low-density amorphous ice (LDA) to high-density amorphous ice (HDA) is influenced by the preparation of LDA. By studying LDA samples prepared using widely different procedures, we find that the sharpness of the LDA-to-HDA transformation is correlated with the depth of the initial LDA sample in the potential energy landscape (PEL), as characterized by the inherent structure energy. Our results show that the complex phenomenology of the amorphous ices reported in experiments and computer simulations can be understood and predicted in a unified way from knowledge of the PEL of the system.

  19. The Effect of Preintervention Preparation on Pain and Anxiety Related to Peripheral Cannulation Procedures in Children.

    Science.gov (United States)

    Tunç-Tuna, Pinar; Açikgoz, Ayfer

    2015-12-01

    This study was performed to determine the effect of several preintervention preparation practices on pain and anxiety related to the peripheral cannulation procedure in children ages 9-12 years. The study included 60 Turkish children (28 female, 32 male, randomly selected by lot), 30 of whom were included in the intervention group and 30 of whom were included in the control group. The children's demographic data were collected by a data collection form prepared by the researcher. The children in the intervention group read the training manual before peripheral cannulation, and the procedure was demonstrated on a teddy bear. Their level of pain was assessed using the Wong-Baker Faces Rating Scale, and their level of anxiety was determined by the Spielberger State-Trait Anxiety Inventory for Children, before and during the procedure in both groups. Results showed that while anxiety and pain scores increased during the actual procedure compared to the preparatory procedure in the control group (anxiety t = -4.957, pain Z(a) = -4.048), anxiety and pain scores decreased during the actual procedure in the intervention group compared to the preparatory procedure (anxiety t = 7.896, pain t = 6.196). When the pain and anxiety scores were examined, it was found that both anxiety and pain scores in the intervention group were significantly lower than in the control group. In conclusion, children in this study experienced pain and situational anxiety during peripheral cannulation, and this pain can be reduced by preparing the child in advance of the procedure. It is suggested that children should be informed about and able to practice the procedure on a toy or model before peripheral cannulation. Preparation of the children to painful procedures in accordance with their cognitive development can reduce anxiety and pain. Copyright © 2015 American Society for Pain Management Nursing. Published by Elsevier Inc. All rights reserved.

  20. [Progress in sample preparation and analytical methods for trace polar small molecules in complex samples].

    Science.gov (United States)

    Zhang, Qianchun; Luo, Xialin; Li, Gongke; Xiao, Xiaohua

    2015-09-01

    Small polar molecules such as nucleosides, amines, amino acids are important analytes in biological, food, environmental, and other fields. It is necessary to develop efficient sample preparation and sensitive analytical methods for rapid analysis of these polar small molecules in complex matrices. Some typical materials in sample preparation, including silica, polymer, carbon, boric acid and so on, are introduced in this paper. Meanwhile, the applications and developments of analytical methods of polar small molecules, such as reversed-phase liquid chromatography, hydrophilic interaction chromatography, etc., are also reviewed.

  1. Considerations for Sample Preparation Using Size-Exclusion Chromatography for Home and Synchrotron Sources.

    Science.gov (United States)

    Rambo, Robert P

    2017-01-01

    The success of a SAXS experiment for structural investigations depends on two precise measurements, the sample and the buffer background. Buffer matching between the sample and background can be achieved using dialysis methods but in biological SAXS of monodisperse systems, sample preparation is routinely being performed with size exclusion chromatography (SEC). SEC is the most reliable method for SAXS sample preparation as the method not only purifies the sample for SAXS but also almost guarantees ideal buffer matching. Here, I will highlight the use of SEC for SAXS sample preparation and demonstrate using example proteins that SEC purification does not always provide for ideal samples. Scrutiny of the SEC elution peak using quasi-elastic and multi-angle light scattering techniques can reveal hidden features (heterogeneity) of the sample that should be considered during SAXS data analysis. In some cases, sample heterogeneity can be controlled using a small molecule additive and I outline a simple additive screening method for sample preparation.

  2. Standard Operating Procedures for Preparing and Handling Sterile Male Tsetse flies for Release

    International Nuclear Information System (INIS)

    Argiles-Herrero, Rafa; Leak, Stephen G.A.

    2016-01-01

    The purpose of this SOP is to describe the procedures involved in preparing tsetse flies reared in a breeding facility for release in the field for the sterile insect technique (SIT) as a component of Area-Wide Insect pest Management (AW-IPM). Following the procedures which are outlined will help to ensure that the released sterile male tsetse flies are of optimal quality.

  3. A Method for Microalgae Proteomics Analysis Based on Modified Filter-Aided Sample Preparation.

    Science.gov (United States)

    Li, Song; Cao, Xupeng; Wang, Yan; Zhu, Zhen; Zhang, Haowei; Xue, Song; Tian, Jing

    2017-11-01

    With the fast development of microalgal biofuel researches, the proteomics studies of microalgae increased quickly. A filter-aided sample preparation (FASP) method is widely used proteomics sample preparation method since 2009. Here, a method of microalgae proteomics analysis based on modified filter-aided sample preparation (mFASP) was described to meet the characteristics of microalgae cells and eliminate the error caused by over-alkylation. Using Chlamydomonas reinhardtii as the model, the prepared sample was tested by standard LC-MS/MS and compared with the previous reports. The results showed mFASP is suitable for most of occasions of microalgae proteomics studies.

  4. Implication of sample preparation procedures in determination of 137Cs radioactivity in muscle of marine organisms and the radioactivity concentration in the recent years

    International Nuclear Information System (INIS)

    Oikawa, Shinji; Isoyama, Naohiko; Misonoo, Jun

    2009-01-01

    Long-term fluctuation of the yield and ash content of muscle dissected from marine organisms were investigated for establishing a standard of pretreatment procedure based on the data on radioactivity analyses of various biological samples such as fish and shellfish which were collected from 15 sea areas adjacent to nuclear power stations in Japan. The muscle yield in terms of the percentage of muscle weight to the whole raw weight as well as ash content were obtained for 53 species during the period from 1983 to 2007 and subjected to a statistical scrutiny. There was no significant change in general in the muscle yield and ash content, with the exception of some species due to modification of pretreatment method. However those exceptions would not have resulted in a critical change of the level of 137 Cs concentration in marine organisms as a whole in the sea areas of concern, because it was usually expressed as the average for three different species in the present study. The ash content would be useful, nevertheless, as an index to assure the comparability of sample preparation technique. The 137 Cs radioactivity concentration in muscle of marine organisms gradually decreased year by year from 1990 after the Chernobyl nuclear accident, and would not be more than 0.24 Bq/kg-wet, the maximum level during 2003 to 2007, in the future from the viewpoint of fail-safe approaching. (author)

  5. [Preparation of sedation-analgesia procedures in spanish paediatric emergency departments: A descriptive study].

    Science.gov (United States)

    Míguez Navarro, Concepción; Oikonomopoulou, Niki; Lorente Romero, Jorge; Vázquez López, Paula

    2017-07-24

    The objective of this study was to describe the current practice regarding the preparation of the sedation-analgesia (SA) procedures performed in the paediatric emergency centres in Spain. A multicentre, observational and prospective analytical study was carried out on the SA procedures that were performed on children under 18 years-old in 18 paediatric emergency departments between February 2015 and January 2016. A total of 658 SA procedures were registered in 18 hospitals of Spain, most of them to children older than 24 months. The type of the procedure was: simple analgesia in 57 (8.6%), sedation in 44 (6.7%), SA for a not very painful procedure in 275 (41.8%), and SA for a very painful procedure in 282 (42.9%). Informed consent was requested in 98.6% of the cases. The written form was more frequently preferred in the group of patients that received SA for a very painful procedure (76.6%) in comparison to a painful procedure or to simple analgesia (62.9% and 54.4%, respectively, P<.001). The staff that most frequently performed the SA procedures were the paediatricians of the emergency departments (64.3%), followed by Paediatrics Residents (30.7%). The most frequent reasons for the SA were traumatological (35.9%) and surgical (28.4%). Fasting was observed in 81% of the cases. More than two-thirds (67.3%, n=480) children were monitored, the majority (95.8%) of them using pulse oximetry. The pharmacological strategy used was the administration of one drug in 443 (67.3%) of the cases, mostly nitrous oxide, and a combination of drugs in 215 (32.7%), especially midazolam/ketamine (46.9%). The majority of the SA procedures analysed in this study have been carried out correctly and prepared in accordance with the current guidelines. Copyright © 2017. Publicado por Elsevier España, S.L.U.

  6. Improved sample preparation method for environmental plutonium analysis by ICP-SFMS and alpha-spectrometry

    International Nuclear Information System (INIS)

    Varga, Z.; Stefanka, Z.; Suranyi, G.; Vajda, N.

    2007-01-01

    A rapid and simple sample preparation method for plutonium determination in environmental samples by inductively coupled plasma sector field mass spectrometry (ICP-SFMS) and alpha-spectrometry is described. The developed procedure involves a selective CaF 2 co-precipitation for preconcentration followed by extraction chromatographic separation. The proposed method effectively eliminates the possible interferences in mass spectrometric analysis and also removes interfering radionuclides that may disturb alpha-spectrometric measurement. For 239 Pu, 240 Pu and 241 Pu limits of detection of 9.0 fg x g -1 (0.021 mBq), 1.7 fg x g -1 (0.014 mBq) and 3.1 fg x g -1 (11.9 mBq) were achieved by ICP-SFMS, respectively, and 0.02 mBq by alpha-spectrometry. Results of certified reference materials agreed well with the recommended values. (author)

  7. An Efficient and Green Procedure for the Preparation of Acylals from ...

    African Journals Online (AJOL)

    An Efficient and Green Procedure for the Preparation of Acylals from Aldehydes Catalyzed by Alum [KAl(SO 4 ) 2 .12H 2 O] ... South African Journal of Chemistry ... mild reaction conditions, short reaction times and excellent yields, and offers a green synthetic solution by avoiding toxic catalysts and hazardous solvents.

  8. Chapter 8. Medical procedures. Recommendations and standard operating procedures for intensive care unit and hospital preparations for an influenza epidemic or mass disaster

    NARCIS (Netherlands)

    Zimmerman, Janice L.; Sprung, Charles L.; Christian, Michael D.; Camargo, Ruben; Ceraso, Daniel; Azoulay, Elie; Duguet, Alexandre; Guery, Benoit; Reinhart, Konrad; Adini, Bruria; Barlavie, Yaron; Benin-Goren, Odeda; Cohen, Robert; Klein, Motti; Leoniv, Yuval; Margalit, Gila; Rubinovitch, Bina; Sonnenblick, Moshe; Steinberg, Avraham; Weissman, Charles; Wolff, Donna; Kesecioglu, Jozef; de Jong, Menno; Moreno, Rui; An, Youzhong; Du, Bin; Joynt, Gavin M.; Colvin, John; Loo, Shi; Richards, Guy; Artigas, Antonio; Pugin, Jerome; Amundson, Dennis; Devereaux, Asha; Beigel, John; Danis, Marion; Farmer, Chris; Hick, John L.; Maki, Dennis; Masur, Henry; Rubinson, Lewis; Sandrock, Christian; Talmor, Daniel; Truog, Robert; Zimmerman, Janice; Brett, Steve; Montgomery, Hugh; Rhodes, Andrew; Sanderson, Frances; Taylor, Bruce

    2010-01-01

    To provide recommendations and standard operating procedures for intensive care unit and hospital preparations for an influenza pandemic or mass disaster with a specific focus on ensuring that adequate resources are available and appropriate protocols are developed to safely perform procedures in

  9. Protocol for Cohesionless Sample Preparation for Physical Experimentation

    Science.gov (United States)

    2016-05-01

    Standard test method for consolidated drained triaxial compression test for soils . In Annual book of ASTM standards. West Conshohocken, PA: ASTM...derived wherein uncertainties and laboratory scatter associated with soil fabric-behavior variance during sample preparation are mitigated. Samples of...wherein comparable analysis between different laboratory tests’ results can be made by ensuring a comparable soil fabric prior to laboratory testing

  10. Sample Preparation (SS): SE51_SS01 [Metabolonote[Archive

    Lifescience Database Archive (English)

    Full Text Available e Master NEO, BMS, Tokyo, Japan), and the seed powder was extracted with 1 mL of extraction buffer (0.1% HCO...trifugation (4 ℃, 10,000 rpm, 5 min), the sample tubes were subjected to sample preparation (buffer transfer

  11. Correlation of resistance and thermogravimetric measurements of the Er/sub 1/Ba/sub 2/Cu/sub 3/O/sub 9-δ/ superconductor to sample preparation techniques

    International Nuclear Information System (INIS)

    Lee, S.I.; Golben, J.P.; Song, Y.; Chen, X.D.; McMichael, R.D.; Gaines, J.R.

    1987-01-01

    The resistance dependence and thermogravimetric analysis (TGA) of Er/sub 1/Ba/sub 2/Cu/sub 3/O/sub 9-δ/ has been measured in the temperature range 27 C to 920 CV. The heat treatments and oxygen flow rates simulated actual sintering and annealing processes used in sample preparation. Evidence of a phase transition in Er/sub 1/Ba/sub 2/Cu/sub 3/O/sub 9-δ/ near 680 C is discussed, as well as the implications of the maximum oxygen uptake near 400 C. The impact of sample preparation procedures on sample features is also discussed

  12. On-site sampling and sample-preparation approach with a portable sampler based on hollow-fiber/graphene bars for the microextraction of nitrobenzene compounds in lake water.

    Science.gov (United States)

    Xing, Rongrong; Hu, Shuang; Chen, Xuan; Bai, Xiaohong; Feng, Meiqin

    2015-02-01

    A novel on-site sampling and sample-preparation approach was developed and evaluated in the present work. In this procedure, hollow-fiber/graphene bars (HF/GBs) were used for sampling and sample preparation. A handheld battery-operated electric egg beater was utilized to support the HF/GBs and stir the sample solution to facilitate extraction at the sampling site. Four nitrobenzene compounds (nitrobenzene, o-nitrophenol, m-nitrophenol, and p-nitrophenol) were used as model compounds. Several factors affecting performance, including types and amount of graphene used and extraction and desorption times, were investigated and optimized in the laboratory. Under optimized conditions, the enrichment factors of the four nitrobenzene compounds ranged from 46 to 69. Good linearities of 0.01-10 μg/mL with regression coefficients between 0.9917 and 0.9973 were obtained for all analytes. The LOD of the method was 0.3 ng/mL. Satisfactory recoveries (98-102%) and precision (1.0-5.8%) were also achieved. The ultrastructures and extraction mechanism of the HF/GBs were characterized and analyzed. The proposed approach coupled with high-performance liquid chromatography was successfully applied in the extraction and determination of trace nitrobenzene compounds in lake water. Experimental results showed that the approach is simple, convenient, rapid, and practical for routine environmental monitoring. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Challenges in TEM sample preparation of solvothermally grown CuInS2 films.

    Science.gov (United States)

    Frank, Anna; Changizi, Rasa; Scheu, Christina

    2018-06-01

    Transmission electron microscopy (TEM) is a widely used tool to characterize materials. The required samples need to be electron transparent which should be achieved without changing the microstructure. This work describes different TEM sample preparation techniques of nanostructured CuInS 2 thin films on fluorine-doped tin oxide substrates, synthesized solvothermally using l-cysteine as sulfur source. Focused ion beam lamellae, conventional cross section samples and scratch samples have been prepared and investigated. It was possible to prepare appropriate samples with each technique, however, each technique brings with it certain advantages and disadvantages. FIB preparation of solvothermally synthesized CuInS 2 suffers from two main drawbacks. First, the whole CuInS 2 layer displays a strongly increased Cu content caused by Cu migration and preferential removal of In. Further, electron diffraction shows the formation of an additional CuS phase after Ga + bombardment. Second, diffraction analysis is complicated by a strong contribution of crystalline Pt introduced during the FIB preparation and penetrating into the porous film surface. The conventional cross sectional CuInS 2 sample also shows a Cu signal enhancement which is caused by contribution of the brass tube material used for embedding. Additionally, Cu particles have been observed inside the CuInS 2 which have been sputtered on the film during preparation. Only the scratch samples allow an almost artefact-free and reliable elemental quantification using energy-dispersive X-ray spectroscopy. However, scratch samples suffer from the drawback that it is not possible to determine the layer thickness, which is possible for both cross sectional preparation techniques. Consequently, it is concluded that the type of sample preparation should be chosen dependent on the required information. A full characterization can only be achieved when the different techniques are combined. Copyright © 2018 Elsevier Ltd. All

  14. Automated SEM and TEM sample preparation applied to copper/low k materials

    Science.gov (United States)

    Reyes, R.; Shaapur, F.; Griffiths, D.; Diebold, A. C.; Foran, B.; Raz, E.

    2001-01-01

    We describe the use of automated microcleaving for preparation of both SEM and TEM samples as done by SELA's new MC500 and TEMstation tools. The MC500 is an automated microcleaving tool that is capable of producing cleaves with 0.25 μm accuracy resulting in SEM-ready samples. The TEMstation is capable of taking a sample output from the MC500 (or from SELA's earlier MC200 tool) and producing a FIB ready slice of 25±5 μm, mounted on a TEM-washer and ready for FIB thinning to electron transparency for TEM analysis. The materials selected for the tool set evaluation mainly included the Cu/TaN/HOSP low-k system. The paper is divided into three sections, experimental approach, SEM preparation and analysis of HOSP low-k, and TEM preparation and analysis of Cu/TaN/HOSP low-k samples. For the samples discussed, data is presented to show the quality of preparation provided by these new automated tools.

  15. Optimization of Sample Preparation processes of Bone Material for Raman Spectroscopy.

    Science.gov (United States)

    Chikhani, Madelen; Wuhrer, Richard; Green, Hayley

    2018-03-30

    Raman spectroscopy has recently been investigated for use in the calculation of postmortem interval from skeletal material. The fluorescence generated by samples, which affects the interpretation of Raman data, is a major limitation. This study compares the effectiveness of two sample preparation techniques, chemical bleaching and scraping, in the reduction of fluorescence from bone samples during testing with Raman spectroscopy. Visual assessment of Raman spectra obtained at 1064 nm excitation following the preparation protocols indicates an overall reduction in fluorescence. Results demonstrate that scraping is more effective at resolving fluorescence than chemical bleaching. The scraping of skeletonized remains prior to Raman analysis is a less destructive method and allows for the preservation of a bone sample in a state closest to its original form, which is beneficial in forensic investigations. It is recommended that bone scraping supersedes chemical bleaching as the preferred method for sample preparation prior to Raman spectroscopy. © 2018 American Academy of Forensic Sciences.

  16. Assessment of the effects of different sample perfusion procedures on phase-contrast tomographic images of mouse spinal cord

    Science.gov (United States)

    Stefanutti, E.; Sierra, A.; Miocchi, P.; Massimi, L.; Brun, F.; Maugeri, L.; Bukreeva, I.; Nurmi, A.; Begani Provinciali, G.; Tromba, G.; Gröhn, O.; Giove, F.; Cedola, A.; Fratini, M.

    2018-03-01

    Synchrotron X-ray Phase Contrast micro-Tomography (SXrPCμT) is a powerful tool in the investigation of biological tissues, including the central nervous system (CNS), and it allows to simultaneously detect the vascular and neuronal network avoiding contrast agents or destructive sample preparations. However, specific sample preparation procedures aimed to optimize the achievable contrast- and signal-to-noise ratio (CNR and SNR, respectively) are required. Here we report and discuss the effects of perfusion with two different fixative agents (ethanol and paraformaldehyde) and with a widely used contrast medium (MICROFIL®) on mouse spinal cord. As a main result, we found that ethanol enhances contrast at the grey/white matter interface and increases the contrast in correspondence of vascular features and fibres, thus providing an adequate spatial resolution to visualise the vascular network at the microscale. On the other hand, ethanol is known to induce tissue dehydration, likely reducing cell dimensions below the spatial resolution limit imposed by the experimental technique. Nonetheless, neurons remain well visible using either perfused paraformaldehyde or MICROFIL® compound, as these latter media do not affect tissues with dehydration effects. Paraformaldehyde appears as the best compromise: it is not a contrast agent, like MICROFIL®, but it is less invasive than ethanol and permits to visualise well both cells and blood vessels. However, a quantitative estimation of the relative grey matter volume of each sample has led us to conclude that no significant alterations in the grey matter extension compared to the white matter occur as a consequence of the perfusion procedures tested in this study.

  17. State of the art in sample preparation for trace element analysis (M1)

    International Nuclear Information System (INIS)

    Barnes, R.M.

    2002-01-01

    Full text: The accelerated capabilities of modern trace element analysis techniques, especially inductively coupled plasma mass spectrometry (ICP-MS), have challenged the sample preparation competence of most laboratories. Exceptional analytical sensitivity, remarkable analysis speed, automated sample presentation, and intelligent sample sequencing of modern spectroscopic instrumentation have lead to demanding requirements for appropriate sample preparation steps needed for ultra trace concentration and speciation measurements. Contamination control, reliable digestion and extraction techniques, presentation of chemical forms, sample matrix management, and intelligent sample processing available today are often inadequate for the most demanding measurements. Some commercial instrumentation provides convenient implementation of well-established contamination control measures, and reagent and container purity are steadily being improved. Direct sample introduction approaches offer alternatives to conventional solution samples, but achieving calibration reliability is difficult. Developing new sample preparation chemistry is especially arduous and rare, yet progress exists in characterizing microwave-assisted reactions. This presentation will describe contemporary targets for modern sample preparation approaches for ultra trace elemental analysis and the likelihood that they can be reasonably achieved. (author)

  18. Miniaturized Sample Preparation and Rapid Detection of Arsenite in Contaminated Soil Using a Smartphone

    Directory of Open Access Journals (Sweden)

    Mohd Farhan Siddiqui

    2018-03-01

    Full Text Available Conventional methods for analyzing heavy metal contamination in soil and water generally require laboratory equipped instruments, complex procedures, skilled personnel and a significant amount of time. With the advancement in computing and multitasking performances, smartphone-based sensors potentially allow the transition of the laboratory-based analytical processes to field applicable, simple methods. In the present work, we demonstrate the novel miniaturized setup for simultaneous sample preparation and smartphone-based optical sensing of arsenic As(III in the contaminated soil. Colorimetric detection protocol utilizing aptamers, gold nanoparticles and NaCl have been optimized and tested on the PDMS-chip to obtain the high sensitivity with the limit of detection of 0.71 ppm (in the sample and a correlation coefficient of 0.98. The performance of the device is further demonstrated through the comparative analysis of arsenic-spiked soil samples with standard laboratory method, and a good agreement with a correlation coefficient of 0.9917 and the average difference of 0.37 ppm, are experimentally achieved. With the android application on the device to run the experiment, the whole process from sample preparation to detection is completed within 3 hours without the necessity of skilled personnel. The approximate cost of setup is estimated around 1 USD, weight 55 g. Therefore, the presented method offers the simple, rapid, portable and cost-effective means for onsite sensing of arsenic in soil. Combined with the geometric information inside the smartphones, the system will allow the monitoring of the contamination status of soils in a nation-wide manner.

  19. Miniaturized Sample Preparation and Rapid Detection of Arsenite in Contaminated Soil Using a Smartphone.

    Science.gov (United States)

    Siddiqui, Mohd Farhan; Kim, Soocheol; Jeon, Hyoil; Kim, Taeho; Joo, Chulmin; Park, Seungkyung

    2018-03-04

    Conventional methods for analyzing heavy metal contamination in soil and water generally require laboratory equipped instruments, complex procedures, skilled personnel and a significant amount of time. With the advancement in computing and multitasking performances, smartphone-based sensors potentially allow the transition of the laboratory-based analytical processes to field applicable, simple methods. In the present work, we demonstrate the novel miniaturized setup for simultaneous sample preparation and smartphone-based optical sensing of arsenic As(III) in the contaminated soil. Colorimetric detection protocol utilizing aptamers, gold nanoparticles and NaCl have been optimized and tested on the PDMS-chip to obtain the high sensitivity with the limit of detection of 0.71 ppm (in the sample) and a correlation coefficient of 0.98. The performance of the device is further demonstrated through the comparative analysis of arsenic-spiked soil samples with standard laboratory method, and a good agreement with a correlation coefficient of 0.9917 and the average difference of 0.37 ppm, are experimentally achieved. With the android application on the device to run the experiment, the whole process from sample preparation to detection is completed within 3 hours without the necessity of skilled personnel. The approximate cost of setup is estimated around 1 USD, weight 55 g. Therefore, the presented method offers the simple, rapid, portable and cost-effective means for onsite sensing of arsenic in soil. Combined with the geometric information inside the smartphones, the system will allow the monitoring of the contamination status of soils in a nation-wide manner.

  20. The effect of sample preparation methods on glass performance

    International Nuclear Information System (INIS)

    Oh, M.S.; Oversby, V.M.

    1990-01-01

    A series of experiments was conducted using SRL 165 synthetic waste glass to investigate the effects of surface preparation and leaching solution composition on the alteration of the glass. Samples of glass with as-cast surfaces produced smooth reaction layers and some evidence for precipitation of secondary phases from solution. Secondary phases were more abundant in samples reacted in deionized water than for those reacted in a silicate solution. Samples with saw-cut surfaces showed a large reduction in surface roughness after 7 days of reaction in either solution. Reaction in silicate solution for up to 91 days produced no further change in surface morphology, while reaction in DIW produced a spongy surface that formed the substrate for further surface layer development. The differences in the surface morphology of the samples may create microclimates that control the details of development of alteration layers on the glass; however, the concentrations of elements in leaching solutions show differences of 50% or less between samples prepared with different surface conditions for tests of a few months duration. 6 refs., 7 figs., 1 tab

  1. Preparation of Cytology Samples: Tricks of the Trade.

    Science.gov (United States)

    Moore, A Russell

    2017-01-01

    General principles and techniques for collection, preparation, and staining of cytologic samples in the general practice setting are reviewed. Tips for collection of digital images are also discussed. Copyright © 2016 Elsevier Inc. All rights reserved.

  2. Procedures for sampling and sample reduction within quality assurance systems for solid biofuels

    Energy Technology Data Exchange (ETDEWEB)

    NONE

    2005-07-01

    The objective of this experimental study on sampling was to determine the size and number of samples of biofuels required (taken at two sampling points in each case) and to compare two methods of sampling. The first objective of the sample-reduction exercise was to compare the reliability of various sampling methods, and the second objective was to measure the variations introduced as a result of reducing the sample size to form suitable test portions. The materials studied were sawdust, wood chips, wood pellets and bales of straw, and these were analysed for moisture, ash, particle size and chloride. The sampling procedures are described. The study was conducted in Scandinavia. The results of the study were presented in Leipzig in October 2004. The work was carried out as part of the UK's DTI Technology Programme: New and Renewable Energy.

  3. Sample preparation techniques for (p, X) spectrometry

    International Nuclear Information System (INIS)

    Whitehead, N.E.

    1985-01-01

    Samples are ashed at low temperature, using oxygen plasma; a rotary evaporator, and freeze drying speeded up the ashing. The new design of apparatus manufactured was only 10 watt but was as efficient as a 200 watt commercial machine; a circuit diagram is included. Samples of hair and biopsy samples of skin were analysed by the technique. A wool standard was prepared for interlaboratory comparison exercises. It was based on New Zealand merino sheep wool and was 2.9 kg in weight. A washing protocol was developed, which preserves most of the trace element content. The wool was ground in liquid nitrogen using a plastic pestle and beaker, driven by a rotary drill press. (author)

  4. Miniaturised sample preparation method for the multiresidual determination of regulated organohalogenated pollutants and related compounds in wild bird eggs.

    Science.gov (United States)

    Roscales, Jose L; Vicente, Alba; Ramos, Lourdes; Jiménez, Begoña

    2017-08-01

    A simplified, miniaturised matrix solid-phase dispersion (MSPD)-based method allowing the simultaneous extraction and purification of contaminants belonging to selected families of regulated persistent organic pollutants (POPs), i.e. polychlorinated biphenyls (PCBs), organochlorine pesticides (OCPs) and penta- to octa-polybrominated diphenyl ethers (PBDEs), and related contaminants of emerging concern, such as deca-BDE and Dechlorane Plus (DP), has been proposed. Wild bird eggs were used as biotic fat-containing model matrices. Once optimised, the procedure allowed sample preparation to be accomplished within 30 min, in a single step, and with minimal sample and reagent consumption and waste generation. These features contributed to speeding up and greening the analytical process as compared to the large-scale multistep procedures for these types of analyses. The method was combined with gas chromatography-quadrupole mass spectrometry (GC-qMS) for PCB and OCP analysis and with GC-negative ion chemical ionisation-quadrupole mass spectrometry (NCI-qMS) for PBDE and DP determination. The complete analytical method provided satisfactory recoveries of the target compounds (above 83% for all analytes, except for PBDE 209, 63%), although as small an amount of sample as 0.300 g was used. The repeatability of the complete procedure was less than 16% (with the only exception for PCB 153, which looked to be affected by an interference). The limits of detection were in all cases lower than 34 pg g -1 dry weight (as calculated for real samples), demonstrating the feasibility of the proposed procedure for accurate determination of the target compounds in biological samples. The proposed procedure was applied to the analysis of the target POPs in unhatched eggs of wild bird species. Graphical abstract Scheme of the miniaturised methodology proposed for environmental monitoring of POPs and related compounds in wild bird eggs.

  5. Mechanical Conversion for High-Throughput TEM Sample Preparation

    International Nuclear Information System (INIS)

    Kendrick, Anthony B; Moore, Thomas M; Zaykova-Feldman, Lyudmila

    2006-01-01

    This paper presents a novel method of direct mechanical conversion from lift-out sample to TEM sample holder. The lift-out sample is prepared in the FIB using the in-situ liftout Total Release TM method. The mechanical conversion is conducted using a mechanical press and one of a variety of TEM coupons, including coupons for both top-side and back-side thinning. The press joins a probe tip point with attached TEM sample to the sample coupon and separates the complete assembly as a 3mm diameter TEM grid, compatible with commercially available TEM sample holder rods. This mechanical conversion process lends itself well to the high through-put requirements of in-line process control and to materials characterization labs where instrument utilization and sample security are critically important

  6. Use of a holder-vacuum tube device to save on-site hands in preparing urine samples for head-space gas-chromatography, and its application to determine the time allowance for sample sealing.

    Science.gov (United States)

    Kawai, Toshio; Sumino, Kimiaki; Ohashi, Fumiko; Ikeda, Masayuki

    2011-01-01

    To facilitate urine sample preparation prior to head-space gas-chromatographic (HS-GC) analysis. Urine samples containing one of the five solvents (acetone, methanol, methyl ethyl ketone, methyl isobutyl ketone and toluene) at the levels of biological exposure limits were aspirated into a vacuum tube via holder, a device commercially available for venous blood collection (the vacuum tube method). The urine sample, 5 ml, was quantitatively transferred to a 20-ml head-space vial prior to HS-GC analysis. The loaded tubes were stored at +4 ℃ in dark for up to 3 d. The vacuum tube method facilitated on-site procedures of urine sample preparation for HS-GC with no significant loss of solvents in the sample and no need of skilled hands, whereas on-site sample preparation time was significantly reduced. Furthermore, no loss of solvents was detected during the 3-d storage, irrespective of hydrophilic (acetone) or lipophilic solvent (toluene). In a pilot application, high performance of the vacuum tube method in sealing a sample in an air-tight space succeeded to confirm that no solvent will be lost when sealing is completed within 5 min after urine voiding, and that the allowance time is as long as 30 min in case of toluene in urine. The use of the holder-vacuum tube device not only saves hands for transfer of the sample to air-tight space, but facilitates sample storage prior to HS-GC analysis.

  7. Sampling procedures for inventory of commercial volume tree species in Amazon Forest.

    Science.gov (United States)

    Netto, Sylvio P; Pelissari, Allan L; Cysneiros, Vinicius C; Bonazza, Marcelo; Sanquetta, Carlos R

    2017-01-01

    The spatial distribution of tropical tree species can affect the consistency of the estimators in commercial forest inventories, therefore, appropriate sampling procedures are required to survey species with different spatial patterns in the Amazon Forest. For this, the present study aims to evaluate the conventional sampling procedures and introduce the adaptive cluster sampling for volumetric inventories of Amazonian tree species, considering the hypotheses that the density, the spatial distribution and the zero-plots affect the consistency of the estimators, and that the adaptive cluster sampling allows to obtain more accurate volumetric estimation. We use data from a census carried out in Jamari National Forest, Brazil, where trees with diameters equal to or higher than 40 cm were measured in 1,355 plots. Species with different spatial patterns were selected and sampled with simple random sampling, systematic sampling, linear cluster sampling and adaptive cluster sampling, whereby the accuracy of the volumetric estimation and presence of zero-plots were evaluated. The sampling procedures applied to species were affected by the low density of trees and the large number of zero-plots, wherein the adaptive clusters allowed concentrating the sampling effort in plots with trees and, thus, agglutinating more representative samples to estimate the commercial volume.

  8. Delineating sampling procedures: Pedagogical significance of analysing sampling descriptions and their justifications in TESL experimental research reports

    Directory of Open Access Journals (Sweden)

    Jason Miin-Hwa Lim

    2011-04-01

    Full Text Available Teaching second language learners how to write research reports constitutes a crucial component in programmes on English for Specific Purposes (ESP in institutions of higher learning. One of the rhetorical segments in research reports that merit attention has to do with the descriptions and justifications of sampling procedures. This genre-based study looks into sampling delineations in the Method-related sections of research articles on the teaching of English as a second language (TESL written by expert writers and published in eight reputed international refereed journals. Using Swales’s (1990 & 2004 framework, I conducted a quantitative analysis of the rhetorical steps and a qualitative investigation into the language resources employed in delineating sampling procedures. This investigation has considerable relevance to ESP students and instructors as it has yielded pertinent findings on how samples can be appropriately described to meet the expectations of dissertation examiners, reviewers, and supervisors. The findings of this study have furnished insights into how supervisors and instructors can possibly teach novice writers ways of using specific linguistic mechanisms to lucidly describe and convincingly justify the sampling procedures in the Method sections of experimental research reports.

  9. 40 CFR 205.171-2 - Test exhaust system sample selection and preparation.

    Science.gov (United States)

    2010-07-01

    ... Systems § 205.171-2 Test exhaust system sample selection and preparation. (a)(1) Exhaust systems... 40 Protection of Environment 24 2010-07-01 2010-07-01 false Test exhaust system sample selection and preparation. 205.171-2 Section 205.171-2 Protection of Environment ENVIRONMENTAL PROTECTION AGENCY...

  10. Preparation of radioactive ''mixed'' waste samples for measurement of RCRA [Resource Conservation and Recovery Act] organic compounds

    International Nuclear Information System (INIS)

    Tomkins, B.A.; Caton, J.E.

    1987-01-01

    A radioactive ''mixed'' waste typically contains alpha-, beta-, or gamma-emitting radionuclides and varying quantities of semivolatile or volatile organic species, some or all of which may be named specifically by the Resource Conservation and Recovery Act (RCRA). Because there are no acceptable means available currently for disposing of these mixed wastes, they are presently stored above-ground in sealed drums. For this reason, analytical procedures which can determine RCRA organics in radioactive waste are necessary for deciding the proper approach for disposal. An important goal of this work is the development of methods for preparing mixed waste samples in a manner which allows the RCRA organics to be measured in conventional organic analysis laboratories without special precautions. Analytical procedures developed for handling mixed waste samples must satisfy not only the usual constraints present in any trace-level organic chemical determination, but also those needed to insure the protection of the operator from radioactive contamination. Consequently, procedures should be designed to use the least amount of radioactive sample commensurate with achieving acceptable sensitivity with the RCRA analytical methods. Furthermore, the unusual laboratory glassware which would normally be used should be replaced with disposable materials wherever possible, in order to reduce the ''clean-up'' time required, and thereby reduce the operator's exposure to radioactivity. Actual sample handling should be reduced to the absolute minimum. Finally, the final isolate must exhibit a sufficiently low level of alpha, beta, or gamma activity to permit detailed characterization in a conventional organic analysis laboratory. 4 refs., 5 tabs

  11. A random sampling procedure for anisotropic distributions

    International Nuclear Information System (INIS)

    Nagrajan, P.S.; Sethulakshmi, P.; Raghavendran, C.P.; Bhatia, D.P.

    1975-01-01

    A procedure is described for sampling the scattering angle of neutrons as per specified angular distribution data. The cosine of the scattering angle is written as a double Legendre expansion in the incident neutron energy and a random number. The coefficients of the expansion are given for C, N, O, Si, Ca, Fe and Pb and these elements are of interest in dosimetry and shielding. (author)

  12. Droplet Size-Aware and Error-Correcting Sample Preparation Using Micro-Electrode-Dot-Array Digital Microfluidic Biochips.

    Science.gov (United States)

    Li, Zipeng; Lai, Kelvin Yi-Tse; Chakrabarty, Krishnendu; Ho, Tsung-Yi; Lee, Chen-Yi

    2017-12-01

    Sample preparation in digital microfluidics refers to the generation of droplets with target concentrations for on-chip biochemical applications. In recent years, digital microfluidic biochips (DMFBs) have been adopted as a platform for sample preparation. However, there remain two major problems associated with sample preparation on a conventional DMFB. First, only a (1:1) mixing/splitting model can be used, leading to an increase in the number of fluidic operations required for sample preparation. Second, only a limited number of sensors can be integrated on a conventional DMFB; as a result, the latency for error detection during sample preparation is significant. To overcome these drawbacks, we adopt a next generation DMFB platform, referred to as micro-electrode-dot-array (MEDA), for sample preparation. We propose the first sample-preparation method that exploits the MEDA-specific advantages of fine-grained control of droplet sizes and real-time droplet sensing. Experimental demonstration using a fabricated MEDA biochip and simulation results highlight the effectiveness of the proposed sample-preparation method.

  13. Evaluation of sample preparation methods and optimization of nickel determination in vegetable tissues

    Directory of Open Access Journals (Sweden)

    Rodrigo Fernando dos Santos Salazar

    2011-02-01

    Full Text Available Nickel, although essential to plants, may be toxic to plants and animals. It is mainly assimilated by food ingestion. However, information about the average levels of elements (including Ni in edible vegetables from different regions is still scarce in Brazil. The objectives of this study were to: (a evaluate and optimize a method for preparation of vegetable tissue samples for Ni determination; (b optimize the analytical procedures for determination by Flame Atomic Absorption Spectrometry (FAAS and by Electrothermal Atomic Absorption (ETAAS in vegetable samples and (c determine the Ni concentration in vegetables consumed in the cities of Lorena and Taubaté in the Vale do Paraíba, State of São Paulo, Brazil. By means of the analytical technique for determination by ETAAS or FAAS, the results were validated by the test of analyte addition and recovery. The most viable method tested for quantification of this element was HClO4-HNO3 wet digestion. All samples but carrot tissue collected in Lorena contained Ni levels above the permitted by the Brazilian Ministry of Health. The most disturbing results, requiring more detailed studies, were the Ni concentrations measured in carrot samples from Taubaté, where levels were five times higher than permitted by Brazilian regulations.

  14. Automated Blood Sample Preparation Unit (ABSPU) for Portable Microfluidic Flow Cytometry.

    Science.gov (United States)

    Chaturvedi, Akhil; Gorthi, Sai Siva

    2017-02-01

    Portable microfluidic diagnostic devices, including flow cytometers, are being developed for point-of-care settings, especially in conjunction with inexpensive imaging devices such as mobile phone cameras. However, two pervasive drawbacks of these have been the lack of automated sample preparation processes and cells settling out of sample suspensions, leading to inaccurate results. We report an automated blood sample preparation unit (ABSPU) to prevent blood samples from settling in a reservoir during loading of samples in flow cytometers. This apparatus automates the preanalytical steps of dilution and staining of blood cells prior to microfluidic loading. It employs an assembly with a miniature vibration motor to drive turbulence in a sample reservoir. To validate performance of this system, we present experimental evidence demonstrating prevention of blood cell settling, cell integrity, and staining of cells prior to flow cytometric analysis. This setup is further integrated with a microfluidic imaging flow cytometer to investigate cell count variability. With no need for prior sample preparation, a drop of whole blood can be directly introduced to the setup without premixing with buffers manually. Our results show that integration of this assembly with microfluidic analysis provides a competent automation tool for low-cost point-of-care blood-based diagnostics.

  15. Error Analysis of Ceramographic Sample Preparation for Coating Thickness Measurement of Coated Fuel Particles

    International Nuclear Information System (INIS)

    Liu Xiaoxue; Li Ziqiang; Zhao Hongsheng; Zhang Kaihong; Tang Chunhe

    2014-01-01

    The thicknesses of four coatings of HTR coated fuel particle are very important parameters. It is indispensable to control the thickness of four coatings of coated fuel particles for the safety of HTR. A measurement method, ceramographic sample-microanalysis method, to analyze the thickness of coatings was developed. During the process of ceramographic sample-microanalysis, there are two main errors, including ceramographic sample preparation error and thickness measurement error. With the development of microscopic techniques, thickness measurement error can be easily controlled to meet the design requirements. While, due to the coated particles are spherical particles of different diameters ranged from 850 to 1000μm, the sample preparation process will introduce an error. And this error is different from one sample to another. It’s also different from one particle to another in the same sample. In this article, the error of the ceramographic sample preparation was calculated and analyzed. Results show that the error introduced by sample preparation is minor. The minor error of sample preparation guarantees the high accuracy of the mentioned method, which indicates this method is a proper method to measure the thickness of four coatings of coated particles. (author)

  16. A lab-on-a-chip system with integrated sample preparation and loop-mediated isothermal amplification for rapid and quantitative detection of Salmonella spp. in food samples

    DEFF Research Database (Denmark)

    Sun, Yi; Than Linh, Quyen; Hung, Tran Quang

    2015-01-01

    was capable to detect Salmonella at concentration of 50 cells per test within 40 min. The simple design, together with high level of integration, isothermal amplification, and quantitative analysis of multiple samples in short time will greatly enhance the practical applicability of the LOC system for rapid...... amplification (LAMP) for rapid and quantitative detection of Salmonella spp. in food samples. The whole diagnostic procedures including DNA isolation, isothermal amplification, and real-time detection were accomplished in a single chamber. Up to eight samples could be handled simultaneously and the system...... and usually take a few hours to days to complete. In response to the demand for rapid on line or at site detection of pathogens, in this study, we describe for the first time an eight-chamber lab-on-a-chip (LOC) system with integrated magnetic beads-based sample preparation and loop-mediated isothermal...

  17. Miniaturizing EM Sample Preparation: Opportunities, Challenges, and "Visual Proteomics".

    Science.gov (United States)

    Arnold, Stefan A; Müller, Shirley A; Schmidli, Claudio; Syntychaki, Anastasia; Rima, Luca; Chami, Mohamed; Stahlberg, Henning; Goldie, Kenneth N; Braun, Thomas

    2018-03-01

    This review compares and discusses conventional versus miniaturized specimen preparation methods for transmission electron microscopy (TEM). The progress brought by direct electron detector cameras, software developments and automation have transformed transmission cryo-electron microscopy (cryo-EM) and made it an invaluable high-resolution structural analysis tool. In contrast, EM specimen preparation has seen very little progress in the last decades and is now one of the main bottlenecks in cryo-EM. Here, we discuss the challenges faced by specimen preparation for single particle EM, highlight current developments, and show the opportunities resulting from the advanced miniaturized and microfluidic sample grid preparation methods described, such as visual proteomics and time-resolved cryo-EM studies. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  18. Optimized preparation of urine samples for two-dimensional electrophoresis and initial application to patient samples

    DEFF Research Database (Denmark)

    Lafitte, Daniel; Dussol, Bertrand; Andersen, Søren

    2002-01-01

    OBJECTIVE: We optimized of the preparation of urinary samples to obtain a comprehensive map of urinary proteins of healthy subjects and then compared this map with the ones obtained with patient samples to show that the pattern was specific of their kidney disease. DESIGN AND METHODS: The urinary...

  19. Waste minimization in analytical chemistry through innovative sample preparation techniques

    International Nuclear Information System (INIS)

    Smith, L. L.

    1998-01-01

    Because toxic solvents and other hazardous materials are commonly used in analytical methods, characterization procedures result in significant and costly amount of waste. We are developing alternative analytical methods in the radiological and organic areas to reduce the volume or form of the hazardous waste produced during sample analysis. For the radiological area, we have examined high-pressure, closed-vessel microwave digestion as a way to minimize waste from sample preparation operations. Heated solutions of strong mineral acids can be avoided for sample digestion by using the microwave approach. Because reactivity increases with pressure, we examined the use of less hazardous solvents to leach selected contaminants from soil for subsequent analysis. We demonstrated the feasibility of this approach by extracting plutonium from a NET reference material using citric and tartaric acids with microwave digestion. Analytical results were comparable to traditional digestion methods, while hazardous waste was reduced by a factor often. We also evaluated the suitability of other natural acids, determined the extraction performance on a wider variety of soil types, and examined the extraction efficiency of other contaminants. For the organic area, we examined ways to minimize the wastes associated with the determination of polychlorinated biphenyls (PCBs) in environmental samples. Conventional methods for analyzing semivolatile organic compounds are labor intensive and require copious amounts of hazardous solvents. For soil and sediment samples, we have a method to analyze PCBs that is based on microscale extraction using benign solvents (e.g., water or hexane). The extraction is performed at elevated temperatures in stainless steel cells containing the sample and solvent. Gas chromatography-mass spectrometry (GC/MS) was used to quantitate the analytes in the isolated extract. More recently, we developed a method utilizing solid-phase microextraction (SPME) for natural

  20. Analytical characterization of high-level mixed wastes using multiple sample preparation treatments

    International Nuclear Information System (INIS)

    King, A.G.; Baldwin, D.L.; Urie, M.W.; McKinley, S.G.

    1994-01-01

    The Analytical Chemistry Laboratory at the Pacific Northwest Laboratory in Richland, Washington, is actively involved in performing analytical characterization of high-level mixed waste from Hanford's single shell and double shell tank characterization programs. A full suite of analyses is typically performed on homogenized tank core samples. These analytical techniques include inductively-coupled plasma-atomic emission spectroscopy, total organic carbon methods and radiochemistry methods, as well as many others, all requiring some type of remote sample-preparation treatment to solubilize the tank sludge material for analysis. Most of these analytical methods typically use a single sample-preparation treatment, inherently providing elemental information only. To better understand and interpret tank chemistry and assist in identifying chemical compounds, selected analytical methods are performed using multiple sample-preparation treatments. The sample preparation treatments used at Pacific Northwest Laboratory for this work with high-level mixed waste include caustic fusion, acid digestion, and water leach. The type of information available by comparing results from different sample-prep treatments includes evidence for the presence of refractory compounds, acid-soluble compounds, or water-soluble compounds. Problems unique to the analysis of Hanford tank wastes are discussed. Selected results from the Hanford single shell ferrocyanide tank, 241-C-109, are presented, and the resulting conclusions are discussed

  1. Application of bias correction methods to improve U3Si2 sample preparation for quantitative analysis by WDXRF

    International Nuclear Information System (INIS)

    Scapin, Marcos A.; Guilhen, Sabine N.; Azevedo, Luciana C. de; Cotrim, Marycel E.B.; Pires, Maria Ap. F.

    2017-01-01

    The determination of silicon (Si), total uranium (U) and impurities in uranium-silicide (U 3 Si 2 ) samples by wavelength dispersion X-ray fluorescence technique (WDXRF) has been already validated and is currently implemented at IPEN's X-Ray Fluorescence Laboratory (IPEN-CNEN/SP) in São Paulo, Brazil. Sample preparation requires the use of approximately 3 g of H 3 BO 3 as sample holder and 1.8 g of U 3 Si 2 . However, because boron is a neutron absorber, this procedure precludes U 3 Si 2 sample's recovery, which, in time, considering routinely analysis, may account for significant unusable uranium waste. An estimated average of 15 samples per month are expected to be analyzed by WDXRF, resulting in approx. 320 g of U 3 Si 2 that would not return to the nuclear fuel cycle. This not only impacts in production losses, but generates another problem: radioactive waste management. The purpose of this paper is to present the mathematical models that may be applied for the correction of systematic errors when H 3 BO 3 sample holder is substituted by cellulose-acetate {[C 6 H 7 O 2 (OH) 3-m (OOCCH 3 )m], m = 0∼3}, thus enabling U 3 Si 2 sample’s recovery. The results demonstrate that the adopted mathematical model is statistically satisfactory, allowing the optimization of the procedure. (author)

  2. Novel sample preparation for operando TEM of catalysts

    International Nuclear Information System (INIS)

    Miller, Benjamin K.; Barker, Trevor M.; Crozier, Peter A.

    2015-01-01

    A new TEM sample preparation method is developed to facilitate operando TEM of gas phase catalysis. A porous Pyrex-fiber pellet TEM sample was produced, allowing a comparatively large amount of catalyst to be loaded into a standard Gatan furnace-type tantalum heating holder. The increased amount of catalyst present inside the environmental TEM allows quantitative determination of the gas phase products of a catalytic reaction performed in-situ at elevated temperatures. The product gas concentration was monitored using both electron energy loss spectroscopy (EELS) and residual gas analysis (RGA). Imaging of catalyst particles dispersed over the pellet at atomic resolution is challenging, due to charging of the insulating glass fibers. To overcome this limitation, a metal grid is placed into the holder in addition to the pellet, allowing catalyst particles dispersed over the grid to be imaged, while particles in the pellet, which are assumed to experience identical conditions, contribute to the overall catalytic conversion inside the environmental TEM cell. The gas within the cell is determined to be well-mixed, making this assumption reasonable. - Highlights: • High in-situ conversion of CO to CO 2 achieved by a novel TEM sample preparation method. • A 3 mm fiber pellet increases the TEM sample surface area by 50×. • Operando atomic resolution is maintained by also including a 3 mm grid in the sample. • Evidence for a well-mixed gas composition inside the ETEM cell is given

  3. Modern methods of sample preparation for GC analysis

    NARCIS (Netherlands)

    de Koning, S.; Janssen, H.-G.; Brinkman, U.A.Th.

    2009-01-01

    Today, a wide variety of techniques is available for the preparation of (semi-) solid, liquid and gaseous samples, prior to their instrumental analysis by means of capillary gas chromatography (GC) or, increasingly, comprehensive two-dimensional GC (GC × GC). In the past two decades, a large number

  4. Sampling and sample preparation methods for the analysis of trace elements in biological material

    International Nuclear Information System (INIS)

    Sansoni, B.; Iyengar, V.

    1978-05-01

    The authors attempt to give a most systamtic possible treatment of the sample taking and sample preparation of biological material (particularly in human medicine) for trace analysis (e.g. neutron activation analysis, atomic absorption spectrometry). Contamination and loss problems are discussed as well as the manifold problems of the different consistency of solid and liquid biological materials, as well as the stabilization of the sample material. The process of dry and wet ashing is particularly dealt with, where new methods are also described. (RB) [de

  5. Automated dried blood spots standard and QC sample preparation using a robotic liquid handler.

    Science.gov (United States)

    Yuan, Long; Zhang, Duxi; Aubry, Anne-Francoise; Arnold, Mark E

    2012-12-01

    A dried blood spot (DBS) bioanalysis assay involves many steps, such as the preparation of standard (STD) and QC samples in blood, the spotting onto DBS cards, and the cutting-out of the spots. These steps are labor intensive and time consuming if done manually, which, therefore, makes automation very desirable in DBS bioanalysis. A robotic liquid handler was successfully applied to the preparation of STD and QC samples in blood and to spot the blood samples onto DBS cards using buspirone as the model compound. This automated preparation was demonstrated to be accurate and consistent. However the accuracy and precision of automated preparation were similar to those from manual preparation. The effect of spotting volume on accuracy was evaluated and a trend of increasing concentrations of buspirone with increasing spotting volumes was observed. The automated STD and QC sample preparation process significantly improved the efficiency, robustness and safety of DBS bioanalysis.

  6. Green sample preparation for liquid chromatography and capillary electrophoresis of anionic and cationic analytes.

    Science.gov (United States)

    Wuethrich, Alain; Haddad, Paul R; Quirino, Joselito P

    2015-04-21

    A sample preparation device for the simultaneous enrichment and separation of cationic and anionic analytes was designed and implemented in an eight-channel configuration. The device is based on the use of an electric field to transfer the analytes from a large volume of sample into small volumes of electrolyte that was suspended into two glass micropipettes using a conductive hydrogel. This simple, economical, fast, and green (no organic solvent required) sample preparation scheme was evaluated using cationic and anionic herbicides as test analytes in water. The analytical figures of merit and ecological aspects were evaluated against the state-of-the-art sample preparation, solid-phase extraction. A drastic reduction in both sample preparation time (94% faster) and resources (99% less consumables used) was observed. Finally, the technique in combination with high-performance liquid chromatography and capillary electrophoresis was applied to analysis of quaternary ammonium and phenoxypropionic acid herbicides in fortified river water as well as drinking water (at levels relevant to Australian guidelines). The presented sustainable sample preparation approach could easily be applied to other charged analytes or adopted by other laboratories.

  7. NGSI FY15 Final Report. Innovative Sample Preparation for in-Field Uranium Isotopic Determinations

    Energy Technology Data Exchange (ETDEWEB)

    Yoshida, Thomas M. [Los Alamos National Lab. (LANL), Los Alamos, NM (United States); Meyers, Lisa [Los Alamos National Lab. (LANL), Los Alamos, NM (United States)

    2015-11-10

    Our FY14 Final Report included an introduction to the project, background, literature search of uranium dissolution methods, assessment of commercial off the shelf (COTS) automated sample preparation systems, as well as data and results for dissolution of bulk quantities of uranium oxides, and dissolution of uranium oxides from swipe filter materials using ammonium bifluoride (ABF). Also, discussed were reaction studies of solid ABF with uranium oxide that provided a basis for determining the ABF/uranium oxide dissolution mechanism. This report details the final experiments for optimizing dissolution of U3O8 and UO2 using ABF and steps leading to development of a Standard Operating Procedure (SOP) for dissolution of uranium oxides on swipe filters.

  8. Independent assessment of matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) sample preparation quality : Effect of sample preparation on MALDI-MS of synthetic polymers

    NARCIS (Netherlands)

    Kooijman, Pieter C.; Kok, Sander; Honing, Maarten

    2017-01-01

    Rationale: Matrix-assisted laser desorption/ionization mass spectrometry (MALDI-MS) provides detailed and in-depth information about the molecular characteristics of synthetic polymers. To obtain the most accurate results the sample preparation parameters should be chosen to suit the sample and the

  9. Sample Preparation of Corn Seed Tissue to Prevent Analyte Relocations for Mass Spectrometry Imaging

    Science.gov (United States)

    Kim, Shin Hye; Kim, Jeongkwon; Lee, Young Jin; Lee, Tae Geol; Yoon, Sohee

    2017-08-01

    Corn seed tissue sections were prepared by the tape support method using an adhesive tape, and mass spectrometry imaging (MSI) was performed. The effect of heat generated during sample preparation was investigated by time-of-flight secondary mass spectrometry (TOF-SIMS) imaging of corn seed tissue prepared by the tape support and the thaw-mounted methods. Unlike thaw-mounted sample preparation, the tape support method does not cause imaging distortion because of the absence of heat, which can cause migration of the analytes on the sample. By applying the tape-support method, the corn seed tissue was prepared without structural damage and MSI with accurate spatial information of analytes was successfully performed.

  10. Sample Preparation of Corn Seed Tissue to Prevent Analyte Relocations for Mass Spectrometry Imaging.

    Science.gov (United States)

    Kim, Shin Hye; Kim, Jeongkwon; Lee, Young Jin; Lee, Tae Geol; Yoon, Sohee

    2017-08-01

    Corn seed tissue sections were prepared by the tape support method using an adhesive tape, and mass spectrometry imaging (MSI) was performed. The effect of heat generated during sample preparation was investigated by time-of-flight secondary mass spectrometry (TOF-SIMS) imaging of corn seed tissue prepared by the tape support and the thaw-mounted methods. Unlike thaw-mounted sample preparation, the tape support method does not cause imaging distortion because of the absence of heat, which can cause migration of the analytes on the sample. By applying the tape-support method, the corn seed tissue was prepared without structural damage and MSI with accurate spatial information of analytes was successfully performed. Graphical Abstract ᅟ.

  11. Universal Sample Preparation Module for Molecular Analysis in Space, Phase I

    Data.gov (United States)

    National Aeronautics and Space Administration — Lynntech proposes to develop and demonstrate the ability of a compact, light-weight, and automated universal sample preparation module (USPM) to process samples from...

  12. The effects of acid treatment and sample preparation on 40Ar/39Ar ages

    Science.gov (United States)

    Morgan, L. E.; Davidheiser, B.; Kuiper, K.; Wijbrans, J. R.

    2011-12-01

    Practitioners of K-Ar and 40Ar/39Ar geochronology regularly use dilute acids (typically 5-10% hydrofluoric acid (HF)) to clean mineral grains prior to irradiation (in the case of 40Ar/39Ar), and analysis (e.g. Evernden and Curtis, 1965; Dalrymple, 1967). This treatment has been shown to reduce contamination from atmospheric Ar, which consists largely of 40Ar and thus must be differentiated from radiogenic 40Ar* (Evernden and Curtis, 1965). Acid treatments can also remove fine grained material attached to mineral grains, such as glass shards or devitrified glass, which can affect analyses and is difficult to remove by other means (Evernden and Curtis, 1965). Such treatments were originally examined for their efficacy in reducing atmospheric argon contamination (Dalrymple, 1967) but were not assessed for the possibility of leaching Ar* or K differentially, which would affect both K-Ar and 40Ar/39Ar ages. Indeed, Evernden and Curtis (1965) state that they are simply removing the "outer portions of the crystals" and apparently do not account for the potential for leaching of 40Ar* or K from the mass of their host mineral. Moreover, the capabilities of the K-Ar system in the 1960s was limited to a precision of ca. 3-4% on samples of 1-3 Ma (Cox and Dalrymple, 1967). Effects of smaller magnitude could not have been detected at the time. As the developments of the 40Ar/39Ar system and modern mass spectrometer technology have allowed for precision to approach 0.1%, the potential effects of acid treatment during sample preparation warrant revisiting. Additionally, the use of Calgon for sample disintegration has not previously been quantitatively assessed but is used extensively in some laboratories. Here we present a series of experiments from co-irradiated Fish Canyon sanidine (FCs) and Mes-4 (Kuiper et al., 2008). FCs is used as the mineral standard following standard procedures. Mes-4 splits were treated with H2O (10 minutes, ultrasonic), Calgon (10%, overnight at 50

  13. ArF photo resist pattern sample preparation method using FIB without protective coating

    Science.gov (United States)

    Okushima, Hirohisa; Onozuka, Toshihiko; Kuroda, Yasushi; Yaguchi, Toshie; Umemura, Kaoru; Tamochi, Ryuichiro; Watanabe, Kenji; Hasegawa, Norio; Kawata, Isao; Rijpers, Bart

    2006-03-01

    This paper presents a novel method of FIB (FIB: focused ion beam) sample preparation to accurately evaluate critical dimensions and profiles of ArF photo resist patterns without the use of a protective coating on the photo resist. In order to accomplish this, the FIB micro-sampling method that is one of effective FIB milling and fabrication method was employed. First a Si cap is picked up from a silicon wafer and fixed to ArF photo resist patterns to protect against ion beam irradiation. Then, a micro-sample, a piece of Si-capped ArF photo resist, was extracted from the bulk ArF photo resist. In this procedure, this silicon cap always protects ArF photo resist patterns against ion beam irradiation. For the next step, the micro-sample is fixed to a needle stub of the FIB-STEM (STEM: scanning transmission electron microscopy) compatible rotation holder. This sample on the needle stub was rotated 180 degrees and milled from the side of Si substrate. Lastly, the sample is milled to the thickness of 2μm. In this process, the ion beam is irradiating from the silicon substrate side to minimize the ion beam irradiation damages on the ArF photo resist patterns. EDX (EDX: Energy dispersive X-ray spectroscopy) analysis proved that no gallium ions were detected on the surface of the ArF photo resist patterns. The feasibility of high accelerating voltage observation of STEM to observe line edge roughness of a thick sample like 2μm without shrinkage has been demonstrated.

  14. Developments in the preparation of operating procedures for emergency conditions of nuclear power plants

    International Nuclear Information System (INIS)

    1985-06-01

    In recent years a substantial effort has been devoted by the nuclear community to extend Emergency Operating Procedures (EOPs) to cover all conceivable events and to develop procedure formats that transmit the essential guidance to operators in an optimum way. The information given in this report is based upon the most recent developments in formulating and applying EOPs. It should therefore provide guidance to those involved in preparing or reviewing EOPs on the scope, technical basis, organization and format of such procedures. It also outlines the actions required to validate the adequacy and applicability of these procedures so that the correct operator actions are achieved. Examples are given to illustrate the developments in some Member States

  15. A solid phase extraction-ion chromatography with conductivity detection procedure for determining cationic surfactants in surface water samples.

    Science.gov (United States)

    Olkowska, Ewa; Polkowska, Żaneta; Namieśnik, Jacek

    2013-11-15

    A new analytical procedure for the simultaneous determination of individual cationic surfactants (alkyl benzyl dimethyl ammonium chlorides) in surface water samples has been developed. We describe this methodology for the first time: it involves the application of solid phase extraction (SPE-for sample preparation) coupled with ion chromatography-conductivity detection (IC-CD-for the final determination). Mean recoveries of analytes between 79% and 93%, and overall method quantification limits in the range from 0.0018 to 0.038 μg/mL for surface water and CRM samples were achieved. The methodology was applied to the determination of individual alkyl benzyl quaternary ammonium compounds in environmental samples (reservoir water) and enables their presence in such types of waters to be confirmed. In addition, it is a simpler, less time-consuming, labour-intensive, avoiding use of toxic chloroform and significantly less expensive methodology than previously described approaches (liquid-liquid extraction coupled with liquid chromatography-mass spectrometry). Copyright © 2013 Elsevier B.V. All rights reserved.

  16. Current advances and strategies towards fully automated sample preparation for regulated LC-MS/MS bioanalysis.

    Science.gov (United States)

    Zheng, Naiyu; Jiang, Hao; Zeng, Jianing

    2014-09-01

    Robotic liquid handlers (RLHs) have been widely used in automated sample preparation for liquid chromatography-tandem mass spectrometry (LC-MS/MS) bioanalysis. Automated sample preparation for regulated bioanalysis offers significantly higher assay efficiency, better data quality and potential bioanalytical cost-savings. For RLHs that are used for regulated bioanalysis, there are additional requirements, including 21 CFR Part 11 compliance, software validation, system qualification, calibration verification and proper maintenance. This article reviews recent advances in automated sample preparation for regulated bioanalysis in the last 5 years. Specifically, it covers the following aspects: regulated bioanalysis requirements, recent advances in automation hardware and software development, sample extraction workflow simplification, strategies towards fully automated sample extraction, and best practices in automated sample preparation for regulated bioanalysis.

  17. A procedure for the preparation of radioactive thymidine labelled with 14C

    International Nuclear Information System (INIS)

    Nejedly, Z.; Skodova, H.; Culik, K.; Filip, J.; Kolina, J.; Skoda, J.

    1990-01-01

    14 C-Labelled thymidine can be prepared by conversion of labelled or unlabelled thymine. The preparation is carried out in the presence of labelled or unlabelled 2-deoxycytidine, of a surfactant and a of reaction stimulator in a buffer at a temperature of 3 to 38 degC, under the catalytic effect of biocatalysts prepared from Escherichia coli B bacterial cells which are immobilized by embedding into an inert carrier. Sodium dodecyl sulfate can serve as the surfactant, D-glucose as the reaction-stimulating substrate, and sodium alginate as the inert cell carrier. In the procedure suggested, catalytic properties of enzymes are utilized without the need to isolate the enzymes from the bacterial cells beforehand or to purify them. The bacterial cells can be applied repeatedly in several production batches and stored in physiological solution at 5 degC. (M.D.)

  18. From analogue to apps--developing an app to prepare children for medical imaging procedures.

    Science.gov (United States)

    Williams, Gigi; Greene, Siobhan

    2015-01-01

    The Royal Children's Hospital (RCH) in Melbourne has launched a world-first app for children that will help reduce anxiety and the need for anesthesia during medical imaging procedures. The free, game-based app, "Okee in Medical Imaging", helps children aged from four to eight years to prepare for all medical imaging procedures--X-ray, CT, MRI, ultrasound, nuclear medicine, and fluoroscopy. The app is designed to reduce anticipatory fear of imaging procedures, while helping to ensure that children attend imaging appointments equipped with the skills required for efficient and effective scans to be performed. This paper describes how the app was developed.

  19. Sample preparation and detection device for infectious agents

    Science.gov (United States)

    Miles, Robin R.; Wang, Amy W.; Fuller, Christopher K.; Lemoff, Asuncion V.; Bettencourt, Kerry A.; Yu, June

    2003-06-10

    A sample preparation and analysis device which incorporates both immunoassays and PCR assays in one compact, field-portable microchip. The device provides new capabilities in fluid and particle control which allows the building of a fluidic chip with no moving parts, thus decreasing fabrication cost and increasing the robustness of the device. The device can operate in a true continuous (not batch) mode. The device incorporates magnetohydrodynamic (MHD) pumps to move the fluid through the system, acoustic mixing and fractionation, dielectropheretic (DEP) sample concentration and purification, and on-chip optical detection capabilities.

  20. Environmental Sciences Division Toxicology Laboratory standard operating procedures

    International Nuclear Information System (INIS)

    Kszos, L.A.; Stewart, A.J.; Wicker, L.F.; Logsdon, G.M.

    1989-09-01

    This document was developed to provide the personnel working in the Environmental Sciences Division's Toxicology Laboratory with documented methods for conducting toxicity tests. The document consists of two parts. The first part includes the standard operating procedures (SOPs) that are used by the laboratory in conducting toxicity tests. The second part includes reference procedures from the US Environmental Protection Agency document entitled Short-Term Methods for Estimating the Chronic Toxicity of Effluents and Receiving Waters to Freshwater Organisms, upon which the Toxicology Laboratory's SOPs are based. Five of the SOPs include procedures for preparing Ceriodaphnia survival and reproduction test. These SOPs include procedures for preparing Ceriodaphnia food (SOP-3), maintaining Ceriodaphnia cultures (SOP-4), conducting the toxicity test (SOP-13), analyzing the test data (SOP-13), and conducting a Ceriodaphnia reference test (SOP-15). Five additional SOPs relate specifically to the fathead minnow (Pimephales promelas) larval survival and growth test: methods for preparing fathead minnow larvae food (SOP-5), maintaining fathead minnow cultures (SOP-6), conducting the toxicity test (SOP-9), analyzing the test data (SOP-12), and conducting a fathead minnow reference test (DOP-14). The six remaining SOPs describe methods that are used with either or both tests: preparation of control/dilution water (SOP-1), washing of glassware (SOP-2), collection and handling of samples (SOP-7), preparation of samples (SOP-8), performance of chemical analyses (SOP-11), and data logging and care of technical notebooks (SOP-16)

  1. Automated radioanalytical system incorporating microwave-assisted sample preparation, chemical separation, and online radiometric detection for the monitoring of total 99Tc in nuclear waste processing streams.

    Science.gov (United States)

    Egorov, Oleg B; O'Hara, Matthew J; Grate, Jay W

    2012-04-03

    An automated fluidic instrument is described that rapidly determines the total (99)Tc content of aged nuclear waste samples, where the matrix is chemically and radiologically complex and the existing speciation of the (99)Tc is variable. The monitor links microwave-assisted sample preparation with an automated anion exchange column separation and detection using a flow-through solid scintillator detector. The sample preparation steps acidify the sample, decompose organics, and convert all Tc species to the pertechnetate anion. The column-based anion exchange procedure separates the pertechnetate from the complex sample matrix, so that radiometric detection can provide accurate measurement of (99)Tc. We developed a preprogrammed spike addition procedure to automatically determine matrix-matched calibration. The overall measurement efficiency that is determined simultaneously provides a self-diagnostic parameter for the radiochemical separation and overall instrument function. Continuous, automated operation was demonstrated over the course of 54 h, which resulted in the analysis of 215 samples plus 54 hly spike-addition samples, with consistent overall measurement efficiency for the operation of the monitor. A sample can be processed and measured automatically in just 12.5 min with a detection limit of 23.5 Bq/mL of (99)Tc in low activity waste (0.495 mL sample volume), with better than 10% RSD precision at concentrations above the quantification limit. This rapid automated analysis method was developed to support nuclear waste processing operations planned for the Hanford nuclear site.

  2. On the assessment of extremely low breakdown probabilities by an inverse sampling procedure [gaseous insulation

    DEFF Research Database (Denmark)

    Thyregod, Poul; Vibholm, Svend

    1991-01-01

    the flashover probability function and the corresponding distribution of first breakdown voltages under the inverse sampling procedure, and show how this relation may be utilized to assess the single-shot flashover probability corresponding to the observed average first breakdown voltage. Since the procedure......First breakdown voltages obtained under the inverse sampling procedure assuming a double exponential flashover probability function are discussed. An inverse sampling procedure commences the voltage application at a very low level, followed by applications at stepwise increased levels until...... is based on voltage applications in the neighbourhood of the quantile under investigation, the procedure is found to be insensitive to the underlying distributional assumptions...

  3. High-resolution X-ray diffraction with no sample preparation.

    Science.gov (United States)

    Hansford, G M; Turner, S M R; Degryse, P; Shortland, A J

    2017-07-01

    It is shown that energy-dispersive X-ray diffraction (EDXRD) implemented in a back-reflection geometry is extremely insensitive to sample morphology and positioning even in a high-resolution configuration. This technique allows high-quality X-ray diffraction analysis of samples that have not been prepared and is therefore completely non-destructive. The experimental technique was implemented on beamline B18 at the Diamond Light Source synchrotron in Oxfordshire, UK. The majority of the experiments in this study were performed with pre-characterized geological materials in order to elucidate the characteristics of this novel technique and to develop the analysis methods. Results are presented that demonstrate phase identification, the derivation of precise unit-cell parameters and extraction of microstructural information on unprepared rock samples and other sample types. A particular highlight was the identification of a specific polytype of a muscovite in an unprepared mica schist sample, avoiding the time-consuming and difficult preparation steps normally required to make this type of identification. The technique was also demonstrated in application to a small number of fossil and archaeological samples. Back-reflection EDXRD implemented in a high-resolution configuration shows great potential in the crystallographic analysis of cultural heritage artefacts for the purposes of scientific research such as provenancing, as well as contributing to the formulation of conservation strategies. Possibilities for moving the technique from the synchrotron into museums are discussed. The avoidance of the need to extract samples from high-value and rare objects is a highly significant advantage, applicable also in other potential research areas such as palaeontology, and the study of meteorites and planetary materials brought to Earth by sample-return missions.

  4. Application of immunoaffinity columns for different food item samples preparation in micotoxins determination

    Directory of Open Access Journals (Sweden)

    Ćurčić Marijana

    2016-01-01

    Full Text Available In analytical methods used for monitoring of what special attention is paid to sample preparation. Therefore, the objective of this study was testing the efficiency of immunoaffinity columns (IAC that are based on solid phase extraction principles used for samples preparation in determining aflatoxins and ochratoxins. Aflatoxins and ochratoxins concentrations were determined in totally 56 samples of food items: wheat, corn, rice, barley and other grains (19 samples, flour and flour products from grain and additives for the bakery industry (7 samples, fruits and vegetables (3 samples, hazelnut, walnut, almond, coconut flour (4 samples, roasted cocoa beans, peanuts, tea, coffee (16 samples, spices (4 samples and meat and meat products (4 samples. Obtained results indicate advantage of IAC use for sample preparation based on enhanced specificity due to binding of extracted molecules to incorporated specific antibodies and rinsing the rest molecules from sample which could interfere with further analysis. Additional advantage is the usage of small amount of organic solvents and consequently decreased exposure of staff who conduct micotoxins determination. Of special interest is increase in method sensitivity since limit of quantification for aflatoxins and ochratoxins determination method is lower than maximal allowed concentration of these toxines prescribed by national rule book.

  5. HASE - The Helsinki adaptive sample preparation line

    Energy Technology Data Exchange (ETDEWEB)

    Palonen, V., E-mail: vesa.palonen@helsinki.fi [Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 (Finland); Pesonen, A. [Laboratory of Chronology, Finnish Museum of Natural History, P.O. Box 64, FI-00014 (Finland); Herranen, T.; Tikkanen, P. [Department of Physics, University of Helsinki, P.O. Box 43, FI-00014 (Finland); Oinonen, M. [Laboratory of Chronology, Finnish Museum of Natural History, P.O. Box 64, FI-00014 (Finland)

    2013-01-15

    We have designed and built an adaptive sample preparation line with separate modules for combustion, molecular sieve handling, CO{sub 2} gas cleaning, CO{sub 2} storage, and graphitization. The line is also connected to an elemental analyzer. Operation of the vacuum equipment, a flow controller, pressure sensors, ovens, and graphitization reactors are automated with a reliable NI-cRIO real-time system. Stepped combustion can be performed in two ovens at temperatures up to 900 Degree-Sign C. Depending on the application, CuO or O{sub 2}-flow combustion can be used. A flow controller is used to adjust the O{sub 2} flow and pressure during combustion. For environmental samples, a module for molecular sieve regeneration and sample desorption is attached to the line replacing the combustion module. In the storage module, CO{sub 2} samples can be stored behind a gas-tight diaphragm valve and either stored for later graphitization or taken for measurements with separate equipment (AMS gas ion source or a separate mass spectrometer). The graphitization module consists of four automated reactors, capable of graphitizing samples with masses from 3 mg down to 50 {mu}g.

  6. Relations among conceptual knowledge, procedural knowledge, and procedural flexibility in two samples differing in prior knowledge.

    Science.gov (United States)

    Schneider, Michael; Rittle-Johnson, Bethany; Star, Jon R

    2011-11-01

    Competence in many domains rests on children developing conceptual and procedural knowledge, as well as procedural flexibility. However, research on the developmental relations between these different types of knowledge has yielded unclear results, in part because little attention has been paid to the validity of the measures or to the effects of prior knowledge on the relations. To overcome these problems, we modeled the three constructs in the domain of equation solving as latent factors and tested (a) whether the predictive relations between conceptual and procedural knowledge were bidirectional, (b) whether these interrelations were moderated by prior knowledge, and (c) how both constructs contributed to procedural flexibility. We analyzed data from 2 measurement points each from two samples (Ns = 228 and 304) of middle school students who differed in prior knowledge. Conceptual and procedural knowledge had stable bidirectional relations that were not moderated by prior knowledge. Both kinds of knowledge contributed independently to procedural flexibility. The results demonstrate how changes in complex knowledge structures contribute to competence development.

  7. Gel-aided sample preparation (GASP)--a simplified method for gel-assisted proteomic sample generation from protein extracts and intact cells.

    Science.gov (United States)

    Fischer, Roman; Kessler, Benedikt M

    2015-04-01

    We describe a "gel-assisted" proteomic sample preparation method for MS analysis. Solubilized protein extracts or intact cells are copolymerized with acrylamide, facilitating denaturation, reduction, quantitative cysteine alkylation, and matrix formation. Gel-aided sample preparation has been optimized to be highly flexible, scalable, and to allow reproducible sample generation from 50 cells to milligrams of protein extracts. This methodology is fast, sensitive, easy-to-use on a wide range of sample types, and accessible to nonspecialists. © 2014 The Authors. PROTEOMICS published by Wiley-VCH Verlag GmbH & Co. KGaA, Weinheim.

  8. EML procedures manual

    International Nuclear Information System (INIS)

    Volchok, H.L.; de Planque, G.

    1982-01-01

    This manual contains the procedures that are used currently by the Environmental Measurements Laboratory of the US Department of Energy. In addition a number of analytical methods from other laboratories have been included. These were tested for reliability at the Battelle, Pacific Northwest Laboratory under contract with the Division of Biomedical and Environmental Research of the AEC. These methods are clearly distinguished. The manual is prepared in loose leaf form to facilitate revision of the procedures and inclusion of additional procedures or data sheets. Anyone receiving the manual through EML should receive this additional material automatically. The contents are as follows: (1) general; (2) sampling; (3) field measurements; (4) general analytical chemistry; (5) chemical procedures; (6) data section; (7) specifications

  9. A Proteomics Sample Preparation Method for Mature, Recalcitrant Leaves of Perennial Plants

    Science.gov (United States)

    Na, Zhang; Chengying, Lao; Bo, Wang; Dingxiang, Peng; Lijun, Liu

    2014-01-01

    Sample preparation is key to the success of proteomics studies. In the present study, two sample preparation methods were tested for their suitability on the mature, recalcitrant leaves of six representative perennial plants (grape, plum, pear, peach, orange, and ramie). An improved sample preparation method was obtained: Tris and Triton X-100 were added together instead of CHAPS to the lysis buffer, and a 20% TCA-water solution and 100% precooled acetone were added after the protein extraction for the further purification of protein. This method effectively eliminates nonprotein impurities and obtains a clear two-dimensional gel electrophoresis array. The method facilitates the separation of high-molecular-weight proteins and increases the resolution of low-abundance proteins. This method provides a widely applicable and economically feasible technology for the proteomic study of the mature, recalcitrant leaves of perennial plants. PMID:25028960

  10. A proteomics sample preparation method for mature, recalcitrant leaves of perennial plants.

    Directory of Open Access Journals (Sweden)

    Deng Gang

    Full Text Available Sample preparation is key to the success of proteomics studies. In the present study, two sample preparation methods were tested for their suitability on the mature, recalcitrant leaves of six representative perennial plants (grape, plum, pear, peach, orange, and ramie. An improved sample preparation method was obtained: Tris and Triton X-100 were added together instead of CHAPS to the lysis buffer, and a 20% TCA-water solution and 100% precooled acetone were added after the protein extraction for the further purification of protein. This method effectively eliminates nonprotein impurities and obtains a clear two-dimensional gel electrophoresis array. The method facilitates the separation of high-molecular-weight proteins and increases the resolution of low-abundance proteins. This method provides a widely applicable and economically feasible technology for the proteomic study of the mature, recalcitrant leaves of perennial plants.

  11. A reproducible and scalable procedure for preparing bacterial extracts for cell-free protein synthesis.

    Science.gov (United States)

    Katsura, Kazushige; Matsuda, Takayoshi; Tomabechi, Yuri; Yonemochi, Mayumi; Hanada, Kazuharu; Ohsawa, Noboru; Sakamoto, Kensaku; Takemoto, Chie; Shirouzu, Mikako

    2017-11-01

    Cell-free protein synthesis is a useful method for preparing proteins for functional or structural analyses. However, batch-to-batch variability with regard to protein synthesis activity remains a problem for large-scale production of cell extract in the laboratory. To address this issue, we have developed a novel procedure for large-scale preparation of bacterial cell extract with high protein synthesis activity. The developed procedure comprises cell cultivation using a fermentor, harvesting and washing of cells by tangential flow filtration, cell disruption with high-pressure homogenizer and continuous diafiltration. By optimizing and combining these methods, ∼100 ml of the cell extract was prepared from 150 g of Escherichia coli cells. The protein synthesis activities, defined as the yield of protein per unit of absorbance at 260 nm of the cell extract, were shown to be reproducible, and the average activity of several batches was twice that obtained using a previously reported method. In addition, combinatorial use of the high-pressure homogenizer and diafiltration increased the scalability, indicating that the cell concentration at disruption varies from 0.04 to 1 g/ml. Furthermore, addition of Gam protein and examinations of the N-terminal sequence rendered the extract prepared here useful for rapid screening with linear DNA templates. © The Authors 2017. Published by Oxford University Press on behalf of the Japanese Biochemical Society. All rights reserved.

  12. The method of Sample Management in Neutron Activation Analysis Laboratory-Serpong

    International Nuclear Information System (INIS)

    Elisabeth-Ratnawati

    2005-01-01

    In the testing laboratory used by neutron activation analysis method, sample preparation is the main factor and it can't be neglect. The error in the sample preparation can give result with lower accuracy. In this article is explained the scheme of sample preparation i.e sample receive administration, the separate of sample, fluid and solid sample preparation, sample grouping, irradiation, sample counting and holding the sample post irradiation. If the management of samples were good application based on Standard Operation Procedure, therefore each samples has good traceability. To optimize the management of samples is needed the trained and skilled personal and good facility. (author)

  13. On the use of ultracentrifugal devices for routine sample preparation in biomolecular magic-angle-spinning NMR.

    Science.gov (United States)

    Mandal, Abhishek; Boatz, Jennifer C; Wheeler, Travis B; van der Wel, Patrick C A

    2017-03-01

    A number of recent advances in the field of magic-angle-spinning (MAS) solid-state NMR have enabled its application to a range of biological systems of ever increasing complexity. To retain biological relevance, these samples are increasingly studied in a hydrated state. At the same time, experimental feasibility requires the sample preparation process to attain a high sample concentration within the final MAS rotor. We discuss these considerations, and how they have led to a number of different approaches to MAS NMR sample preparation. We describe our experience of how custom-made (or commercially available) ultracentrifugal devices can facilitate a simple, fast and reliable sample preparation process. A number of groups have since adopted such tools, in some cases to prepare samples for sedimentation-style MAS NMR experiments. Here we argue for a more widespread adoption of their use for routine MAS NMR sample preparation.

  14. On the use of ultracentrifugal devices for routine sample preparation in biomolecular magic-angle-spinning NMR

    Energy Technology Data Exchange (ETDEWEB)

    Mandal, Abhishek; Boatz, Jennifer C. [University of Pittsburgh School of Medicine, Department of Structural Biology (United States); Wheeler, Travis B. [University of Pittsburgh School of Medicine, Department of Cell Biology (United States); Wel, Patrick C. A. van der, E-mail: vanderwel@pitt.edu [University of Pittsburgh School of Medicine, Department of Structural Biology (United States)

    2017-03-15

    A number of recent advances in the field of magic-angle-spinning (MAS) solid-state NMR have enabled its application to a range of biological systems of ever increasing complexity. To retain biological relevance, these samples are increasingly studied in a hydrated state. At the same time, experimental feasibility requires the sample preparation process to attain a high sample concentration within the final MAS rotor. We discuss these considerations, and how they have led to a number of different approaches to MAS NMR sample preparation. We describe our experience of how custom-made (or commercially available) ultracentrifugal devices can facilitate a simple, fast and reliable sample preparation process. A number of groups have since adopted such tools, in some cases to prepare samples for sedimentation-style MAS NMR experiments. Here we argue for a more widespread adoption of their use for routine MAS NMR sample preparation.

  15. On-chip sample preparation for complete blood count from raw blood.

    Science.gov (United States)

    Nguyen, John; Wei, Yuan; Zheng, Yi; Wang, Chen; Sun, Yu

    2015-03-21

    This paper describes a monolithic microfluidic device capable of on-chip sample preparation for both RBC and WBC measurements from whole blood. For the first time, on-chip sample processing (e.g. dilution, lysis, and filtration) and downstream single cell measurement were fully integrated to enable sample preparation and single cell analysis from whole blood on a single device. The device consists of two parallel sub-systems that perform sample processing and electrical measurements for measuring RBC and WBC parameters. The system provides a modular environment capable of handling solutions of various viscosities by adjusting the length of channels and precisely controlling mixing ratios, and features a new 'offset' filter configuration for increased duration of device operation. RBC concentration, mean corpuscular volume (MCV), cell distribution width, WBC concentration and differential are determined by electrical impedance measurement. Experimental characterization of over 100,000 cells from 10 patient blood samples validated the system's capability for performing on-chip raw blood processing and measurement.

  16. Difficulties in preparing a standard sample of uranium metal having traces of nitrogen

    International Nuclear Information System (INIS)

    Toteja, R.S.D.; Jangida, B.L.; Sundaresan, M.

    1991-01-01

    Normally in the analysis of uranium for nitrogen, the nitrides are hydrolysed to give NH 3 and that for standardisation purposes to approximate the closest conditions of analysis of ammonia, NH 4 Cl is added to the sample and the recovery is tested. An appropriate method will be to have a standard sample of uranium with known amounts of nitrogen to be used as reference sample. The present work describes the efforts made in the preparation of such a reference sample and a general assessment of such methods available. In present work, known microamounts of nitrogen in an enclosed volume were allowed to react at a temperature of 773 K with a fixed amount of uranium metal of nitrogen content determined chemically. As the reaction of nitrogen with uranium is essentially a surface reaction, a sample had to be homogenised by allowing the nitrided sample to melt at about 1500 K and allow the nitrogen to diffuse through so that the concentration gradient along the profile will disappear. Attempts were made to prepare such samples in the range to 40 to 100 ppm of nitrogen. The density differences of uranium nitride and uranium metal made this diffusion and homogenisation process difficult. The prepared samples were analysed by the micro-kjeldahl's method and the recoveries tested. The equipment used for the preparation of the nitrided samples, for homogenisation and analysis of the results obtained are detailed in the paper together with the assessment of the general methods. (author). 2 refs., 1 fig., 1 tab

  17. Imaging of fullerene-like structures in CNx thin films by electron microscopy; sample preparation artefacts due to ion-beam milling

    International Nuclear Information System (INIS)

    Czigany, Zs.; Neidhardt, J.; Brunell, I.F.; Hultman, L.

    2003-01-01

    The microstructure of CN x thin films, deposited by reactive magnetron sputtering, was investigated by transmission electron microscopy (TEM) at 200 kV in plan-view and cross-sectional samples. Imaging artefacts arise in high-resolution TEM due to overlap of nm-sized fullerene-like features for specimen thickness above 5 nm. The thinnest and apparently artefact-free areas were obtained at the fracture edges of plan-view specimens floated-off from NaCl substrates. Cross-sectional samples were prepared by ion-beam milling at low energy to minimize sample preparation artefacts. The depth of the ion-bombardment-induced surface amorphization was determined by TEM cross sections of ion-milled fullerene-like CN x surfaces. The thickness of the damaged surface layer at 5 deg. grazing incidence was 13 and 10 nm at 3 and 0.8 keV, respectively, which is approximately three times larger than that observed on Si prepared under the same conditions. The shallowest damage depth, observed for 0.25 keV, was less than 1 nm. Chemical changes due to N loss and graphitization were also observed by X-ray photoelectron spectroscopy. As a consequence of chemical effects, sputtering rates of CN x films were similar to that of Si, which enables relatively fast ion-milling procedure compared to carbon compounds. No electron beam damage of fullerene-like CN x was observed at 200 kV

  18. imFASP: An integrated approach combining in-situ filter-aided sample pretreatment with microwave-assisted protein digestion for fast and efficient proteome sample preparation.

    Science.gov (United States)

    Zhao, Qun; Fang, Fei; Wu, Ci; Wu, Qi; Liang, Yu; Liang, Zhen; Zhang, Lihua; Zhang, Yukui

    2016-03-17

    An integrated sample preparation method, termed "imFASP", which combined in-situ filter-aided sample pretreatment and microwave-assisted trypsin digestion, was developed for preparation of microgram and even nanogram amounts of complex protein samples with high efficiency in 1 h. For imFASP method, proteins dissolved in 8 M urea were loaded onto a filter device with molecular weight cut off (MWCO) as 10 kDa, followed by in-situ protein preconcentration, denaturation, reduction, alkylation, and microwave-assisted tryptic digestion. Compared with traditional in-solution sample preparation method, imFASP method generated more protein and peptide identifications (IDs) from preparation of 45 μg Escherichia coli protein sample due to the higher efficiency, and the sample preparation throughput was significantly improved by 14 times (1 h vs. 15 h). More importantly, when the starting amounts of E. coli cell lysate decreased to nanogram level (50-500 ng), the protein and peptide identified by imFASP method were improved at least 30% and 44%, compared with traditional in-solution preparation method, suggesting dramatically higher peptide recovery of imFASP method for trace amounts of complex proteome samples. All these results demonstrate that the imFASP method developed here is of high potential for high efficient and high throughput preparation of trace amounts of complex proteome samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  19. Preschooler test or procedure preparation

    Science.gov (United States)

    ... your child during and after the procedure with books, songs, counting, deep breathing, or blowing bubbles. PLAY ... can be present during the procedure. Ask if anesthesia can be used to reduce your child's discomfort. ...

  20. Toddler test or procedure preparation

    Science.gov (United States)

    ... a test or procedure: Explain the procedure in language your child understands, using plain words. Avoid abstract terms. Make sure your child understands the exact body part involved in the test, and that the ...

  1. A review of sample preparation and its influence on pH determination in concrete samples

    International Nuclear Information System (INIS)

    Manso, S.; Aguado, A.

    2017-01-01

    If we are to monitor the chemical processes in cementitious materials, then pH assays in the pore solutions of cement pastes, mortars, and concretes are of key importance. However, there is no standard method that regulates the sample-preparation method for pH determination. The state-of-the-art of different methods for pH determination in cementitious materials is presented in this paper and the influence of sample preparation in each case. Moreover, an experimental campaign compares three different techniques for pH determination. Its results contribute to establishing a basic criterion to help researchers select the most suitable method, depending on the purpose of the research. A simple tool is described for selecting the easiest and the most economic pH determination method, depending on the objective; especially for researchers and those with limited experience in this field.

  2. A user-friendly robotic sample preparation program for fully automated biological sample pipetting and dilution to benefit the regulated bioanalysis.

    Science.gov (United States)

    Jiang, Hao; Ouyang, Zheng; Zeng, Jianing; Yuan, Long; Zheng, Naiyu; Jemal, Mohammed; Arnold, Mark E

    2012-06-01

    Biological sample dilution is a rate-limiting step in bioanalytical sample preparation when the concentrations of samples are beyond standard curve ranges, especially when multiple dilution factors are needed in an analytical run. We have developed and validated a Microsoft Excel-based robotic sample preparation program (RSPP) that automatically transforms Watson worklist sample information (identification, sequence and dilution factor) to comma-separated value (CSV) files. The Freedom EVO liquid handler software imports and transforms the CSV files to executable worklists (.gwl files), allowing the robot to perform sample dilutions at variable dilution factors. The dynamic dilution range is 1- to 1000-fold and divided into three dilution steps: 1- to 10-, 11- to 100-, and 101- to 1000-fold. The whole process, including pipetting samples, diluting samples, and adding internal standard(s), is accomplished within 1 h for two racks of samples (96 samples/rack). This platform also supports online sample extraction (liquid-liquid extraction, solid-phase extraction, protein precipitation, etc.) using 96 multichannel arms. This fully automated and validated sample dilution and preparation process has been applied to several drug development programs. The results demonstrate that application of the RSPP for fully automated sample processing is efficient and rugged. The RSPP not only saved more than 50% of the time in sample pipetting and dilution but also reduced human errors. The generated bioanalytical data are accurate and precise; therefore, this application can be used in regulated bioanalysis.

  3. Determination of calcium, potassium, manganese, iron, copper and zinc levels in representative samples of two onion cultivars using total reflection X-ray fluorescence and ultrasound extraction procedure

    International Nuclear Information System (INIS)

    Alvarez, J.; Marco, L.M.; Arroyo, J.; Greaves, E.D.; Rivas, R.

    2003-01-01

    The chemical characterization of onion cultivar samples is an important tool for the enhancement of their productivity due to the fact that chemical composition is closed related to the quality of the products. A new sample preparation procedure for elemental characterization is proposed, involving the acid extraction of the analytes from crude samples by means of an ultrasonic bath, avoiding the required digestion of samples in vegetable tissue analysis. The technique of total reflection X-ray fluorescence (TXRF) was successfully applied for the simultaneous determination of the elements Ca, K, Mn, Fe, Cu and Zn. The procedure was compared with the wet ashing and dry ashing procedures for all the elements using multivariate analysis and the Scheffe test. The technique of flame atomic absorption spectrometry (FAAS) was employed for comparison purposes and accuracy evaluation of the proposed analysis method. A good agreement between the two techniques was found when using the dry ashing and ultrasound leaching procedures. The levels of each element found for representative samples of two onion cultivars (Yellow Granex PRR 502 and 438 Granex) were also compared by the same method. Levels of K, Mn and Zn were significantly higher in the 438 Granex cultivar, while levels of Ca, Fe and Cu were significantly higher in the Yellow Granex PRR 502 cultivar

  4. U.S. Geological Survey Noble Gas Laboratory’s standard operating procedures for the measurement of dissolved gas in water samples

    Science.gov (United States)

    Hunt, Andrew G.

    2015-08-12

    This report addresses the standard operating procedures used by the U.S. Geological Survey’s Noble Gas Laboratory in Denver, Colorado, U.S.A., for the measurement of dissolved gases (methane, nitrogen, oxygen, and carbon dioxide) and noble gas isotopes (helium-3, helium-4, neon-20, neon-21, neon-22, argon-36, argon-38, argon-40, kryton-84, krypton-86, xenon-103, and xenon-132) dissolved in water. A synopsis of the instrumentation used, procedures followed, calibration practices, standards used, and a quality assurance and quality control program is presented. The report outlines the day-to-day operation of the Residual Gas Analyzer Model 200, Mass Analyzer Products Model 215–50, and ultralow vacuum extraction line along with the sample handling procedures, noble gas extraction and purification, instrument measurement procedures, instrumental data acquisition, and calculations for the conversion of raw data from the mass spectrometer into noble gas concentrations per unit mass of water analyzed. Techniques for the preparation of artificial dissolved gas standards are detailed and coupled to a quality assurance and quality control program to present the accuracy of the procedures used in the laboratory.

  5. 45 CFR 640.5 - Responsibilities and procedures for preparation of an environmental impact statement.

    Science.gov (United States)

    2010-10-01

    ... an environmental impact statement. 640.5 Section 640.5 Public Welfare Regulations Relating to Public Welfare (Continued) NATIONAL SCIENCE FOUNDATION COMPLIANCE WITH THE NATIONAL ENVIRONMENTAL POLICY ACT § 640.5 Responsibilities and procedures for preparation of an environmental impact statement. (a) If...

  6. Compact low temperature scanning tunneling microscope with in-situ sample preparation capability

    Energy Technology Data Exchange (ETDEWEB)

    Kim, Jungdae [Department of Physics, The University of Texas, Austin, Texas 78712 (United States); Department of Physics and EHSRC, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Nam, Hyoungdo; Schroeder, Allan; Shih, Chih-Kang, E-mail: shih@physics.utexas.edu [Department of Physics, The University of Texas, Austin, Texas 78712 (United States); Qin, Shengyong [Department of Physics, The University of Texas, Austin, Texas 78712 (United States); Department of Physics, University of Science and Technology of China, Hefei, Anhui 230026 (China); ICQD, Hefei National Laboratory for Physical Sciences at the Microscale, University of Science and Technology of China, Hefei, Anhui 230026 (China); Kim, Sang-ui [Department of Physics and EHSRC, University of Ulsan, Ulsan 680-749 (Korea, Republic of); Eom, Daejin [Korea Research Institute of Standards and Science, Daejeon 305-340 (Korea, Republic of)

    2015-09-15

    We report on the design of a compact low temperature scanning tunneling microscope (STM) having in-situ sample preparation capability. The in-situ sample preparation chamber was designed to be compact allowing quick transfer of samples to the STM stage, which is ideal for preparing temperature sensitive samples such as ultra-thin metal films on semiconductor substrates. Conventional spring suspensions on the STM head often cause mechanical issues. To address this problem, we developed a simple vibration damper consisting of welded metal bellows and rubber pads. In addition, we developed a novel technique to ensure an ultra-high-vacuum (UHV) seal between the copper and stainless steel, which provides excellent reliability for cryostats operating in UHV. The performance of the STM was tested from 2 K to 77 K by using epitaxial thin Pb films on Si. Very high mechanical stability was achieved with clear atomic resolution even when using cryostats operating at 77 K. At 2 K, a clean superconducting gap was observed, and the spectrum was easily fit using the BCS density of states with negligible broadening.

  7. Compact low temperature scanning tunneling microscope with in-situ sample preparation capability.

    Science.gov (United States)

    Kim, Jungdae; Nam, Hyoungdo; Qin, Shengyong; Kim, Sang-ui; Schroeder, Allan; Eom, Daejin; Shih, Chih-Kang

    2015-09-01

    We report on the design of a compact low temperature scanning tunneling microscope (STM) having in-situ sample preparation capability. The in-situ sample preparation chamber was designed to be compact allowing quick transfer of samples to the STM stage, which is ideal for preparing temperature sensitive samples such as ultra-thin metal films on semiconductor substrates. Conventional spring suspensions on the STM head often cause mechanical issues. To address this problem, we developed a simple vibration damper consisting of welded metal bellows and rubber pads. In addition, we developed a novel technique to ensure an ultra-high-vacuum (UHV) seal between the copper and stainless steel, which provides excellent reliability for cryostats operating in UHV. The performance of the STM was tested from 2 K to 77 K by using epitaxial thin Pb films on Si. Very high mechanical stability was achieved with clear atomic resolution even when using cryostats operating at 77 K. At 2 K, a clean superconducting gap was observed, and the spectrum was easily fit using the BCS density of states with negligible broadening.

  8. Automated cellular sample preparation using a Centrifuge-on-a-Chip.

    Science.gov (United States)

    Mach, Albert J; Kim, Jae Hyun; Arshi, Armin; Hur, Soojung Claire; Di Carlo, Dino

    2011-09-07

    The standard centrifuge is a laboratory instrument widely used by biologists and medical technicians for preparing cell samples. Efforts to automate the operations of concentration, cell separation, and solution exchange that a centrifuge performs in a simpler and smaller platform have had limited success. Here, we present a microfluidic chip that replicates the functions of a centrifuge without moving parts or external forces. The device operates using a purely fluid dynamic phenomenon in which cells selectively enter and are maintained in microscale vortices. Continuous and sequential operation allows enrichment of cancer cells from spiked blood samples at the mL min(-1) scale, followed by fluorescent labeling of intra- and extra-cellular antigens on the cells without the need for manual pipetting and washing steps. A versatile centrifuge-analogue may open opportunities in automated, low-cost and high-throughput sample preparation as an alternative to the standard benchtop centrifuge in standardized clinical diagnostics or resource poor settings.

  9. Radioactive preparations. Determination of radiochemical purity by thin-layer chromatography

    International Nuclear Information System (INIS)

    1986-01-01

    The standard sets the data which must be attached to every sample, and the equipment, chemicals and auxiliary substances used in the determination of radiochemical purity of substances by chromatography. Described are preparation of the sample, the procedure of sample deposition, the development, drying and detection of the radioactive preparation. The qualitative and quantitative assessment of the radiochromatogram is described as are the calculation of radiochemical purity and the determination of the reproducibility of measurement of radiochemical purity of radioactive preparations. (E.S.)

  10. Ultra-High-Throughput Sample Preparation System for Lymphocyte Immunophenotyping Point-of-Care Diagnostics.

    Science.gov (United States)

    Walsh, David I; Murthy, Shashi K; Russom, Aman

    2016-10-01

    Point-of-care (POC) microfluidic devices often lack the integration of common sample preparation steps, such as preconcentration, which can limit their utility in the field. In this technology brief, we describe a system that combines the necessary sample preparation methods to perform sample-to-result analysis of large-volume (20 mL) biopsy model samples with staining of captured cells. Our platform combines centrifugal-paper microfluidic filtration and an analysis system to process large, dilute biological samples. Utilizing commercialization-friendly manufacturing methods and materials, yielding a sample throughput of 20 mL/min, and allowing for on-chip staining and imaging bring together a practical, yet powerful approach to microfluidic diagnostics of large, dilute samples. © 2016 Society for Laboratory Automation and Screening.

  11. Ionic liquids: solvents and sorbents in sample preparation.

    Science.gov (United States)

    Clark, Kevin D; Emaus, Miranda N; Varona, Marcelino; Bowers, Ashley N; Anderson, Jared L

    2018-01-01

    The applications of ionic liquids (ILs) and IL-derived sorbents are rapidly expanding. By careful selection of the cation and anion components, the physicochemical properties of ILs can be altered to meet the requirements of specific applications. Reports of IL solvents possessing high selectivity for specific analytes are numerous and continue to motivate the development of new IL-based sample preparation methods that are faster, more selective, and environmentally benign compared to conventional organic solvents. The advantages of ILs have also been exploited in solid/polymer formats in which ordinarily nonspecific sorbents are functionalized with IL moieties in order to impart selectivity for an analyte or analyte class. Furthermore, new ILs that incorporate a paramagnetic component into the IL structure, known as magnetic ionic liquids (MILs), have emerged as useful solvents for bioanalytical applications. In this rapidly changing field, this Review focuses on the applications of ILs and IL-based sorbents in sample preparation with a special emphasis on liquid phase extraction techniques using ILs and MILs, IL-based solid-phase extraction, ILs in mass spectrometry, and biological applications. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. Capacitive deionization on-chip as a method for microfluidic sample preparation

    NARCIS (Netherlands)

    Roelofs, Susan Helena; Kim, Bumjoo; Eijkel, Jan C.T.; Han, Jongyoon; van den Berg, Albert; Odijk, Mathieu

    2015-01-01

    Desalination as a sample preparation step is essential for noise reduction and reproducibility of mass spectrometry measurements. A specific example is the analysis of proteins for medical research and clinical applications. Salts and buffers that are present in samples need to be removed before

  13. Sample preparation and biomass determination of SRF model mixture using cryogenic milling and the adapted balance method

    Energy Technology Data Exchange (ETDEWEB)

    Schnöller, Johannes, E-mail: johannes.schnoeller@chello.at; Aschenbrenner, Philipp; Hahn, Manuel; Fellner, Johann; Rechberger, Helmut

    2014-11-15

    Highlights: • An alternative sample comminution procedure for SRF is tested. • Proof of principle is shown on a SRF model mixture. • The biogenic content of the SRF is analyzed with the adapted balance method. • The novel method combines combustion analysis and a data reconciliation algorithm. • Factors for the variance of the analysis results are statistically quantified. - Abstract: The biogenic fraction of a simple solid recovered fuel (SRF) mixture (80 wt% printer paper/20 wt% high density polyethylene) is analyzed with the in-house developed adapted balance method (aBM). This fairly new approach is a combination of combustion elemental analysis (CHNS) and a data reconciliation algorithm based on successive linearisation for evaluation of the analysis results. This method shows a great potential as an alternative way to determine the biomass content in SRF. However, the employed analytical technique (CHNS elemental analysis) restricts the probed sample mass to low amounts in the range of a few hundred milligrams. This requires sample comminution to small grain sizes (<200 μm) to generate representative SRF specimen. This is not easily accomplished for certain material mixtures (e.g. SRF with rubber content) by conventional means of sample size reduction. This paper presents a proof of principle investigation of the sample preparation and analysis of an SRF model mixture with the use of cryogenic impact milling (final sample comminution) and the adapted balance method (determination of biomass content). The so derived sample preparation methodology (cutting mills and cryogenic impact milling) shows a better performance in accuracy and precision for the determination of the biomass content than one solely based on cutting mills. The results for the determination of the biogenic fraction are within 1–5% of the data obtained by the reference methods, selective dissolution method (SDM) and {sup 14}C-method ({sup 14}C-M)

  14. LC-MS analysis of the plasma metabolome–a novel sample preparation strategy

    DEFF Research Database (Denmark)

    Skov, Kasper; Hadrup, Niels; Smedsgaard, Jørn

    2015-01-01

    Blood plasma is a well-known body fluid often analyzed in studies on the effects of toxic compounds as physiological or chemical induced changes in the mammalian body are reflected in the plasma metabolome. Sample preparation prior to LC-MS based analysis of the plasma metabolome is a challenge...... as plasma contains compounds with very different properties. Besides, proteins, which usually are precipitated with organic solvent, phospholipids, are known to cause ion suppression in electrospray mass spectrometry. We have compared two different sample preparation techniques prior to LC-qTOF analysis...... of plasma samples: The first is protein precipitation; the second is protein precipitation followed by solid phase extraction with sub-fractionation into three sub-samples; a phospholipid, a lipid and a polar sub-fraction. Molecular feature extraction of the data files from LC-qTOF analysis of the samples...

  15. Application of hydrocyanic acid vapor generation via focused microwave radiation to the preparation of industrial effluent samples prior to free and total cyanide determinations by spectrophotometric flow injection analysis.

    Science.gov (United States)

    Quaresma, Maria Cristina Baptista; de Carvalho, Maria de Fátima Batista; Meirelles, Francis Assis; Santiago, Vânia Maria Junqueira; Santelli, Ricardo Erthal

    2007-02-01

    A sample preparation procedure for the quantitative determination of free and total cyanides in industrial effluents has been developed that involves hydrocyanic acid vapor generation via focused microwave radiation. Hydrocyanic acid vapor was generated from free cyanides using only 5 min of irradiation time (90 W power) and a purge time of 5 min. The HCN generated was absorbed into an accepting NaOH solution using very simple glassware apparatus that was appropriate for the microwave oven cavity. After that, the cyanide concentration was determined within 90 s using a well-known spectrophotometric flow injection analysis system. Total cyanide analysis required 15 min irradiation time (90 W power), as well as chemical conditions such as the presence of EDTA-acetate buffer solution or ascorbic acid, depending on the effluent to be analyzed (petroleum refinery or electroplating effluents, respectively). The detection limit was 0.018 mg CN l(-1) (quantification limit of 0.05 mg CN l(-1)), and the measured RSD was better than 8% for ten independent analyses of effluent samples (1.4 mg l(-1) cyanide). The accuracy of the procedure was assessed via analyte spiking (with free and complex cyanides) and by performing an independent sample analysis based on the standard methodology recommended by the APHA for comparison. The sample preparation procedure takes only 10 min for free and 20 min for total cyanide, making this procedure much faster than traditional methodologies (conventional heating and distillation), which are time-consuming (they require at least 1 h). Samples from oil (sour and stripping tower bottom waters) and electroplating effluents were analyzed successfully.

  16. A review of sample preparation and its influence on pH determination in concrete samples

    Directory of Open Access Journals (Sweden)

    S. Manso

    2017-01-01

    Full Text Available If we are to monitor the chemical processes in cementitious materials, then pH assays in the pore solutions of cement pastes, mortars, and concretes are of key importance. However, there is no standard method that regulates the sample-preparation method for pH determination. The state-of-the-art of different methods for pH determination in cementitious materials is presented in this paper and the influence of sample preparation in each case. Moreover, an experimental campaign compares three different techniques for pH determination. Its results contribute to establishing a basic criterion to help researchers select the most suitable method, depending on the purpose of the research. A simple tool is described for selecting the easiest and the most economic pH determination method, depending on the objective; especially for researchers and those with limited experience in this field.

  17. A developed wedge fixtures assisted high precision TEM samples pre-thinning method: Towards the batch lamella preparation

    Directory of Open Access Journals (Sweden)

    Dandan Wang

    2017-04-01

    Full Text Available Ion milling, wedge cutting or polishing, and focused ion beam (FIB milling are widely-used techniques for the transmission electron microscope (TEM sample preparation. Especially, the FIB milling provides a site-specific analysis, deposition, and ablation of materials in the micrometer and nanometer scale. However, the cost of FIB tools has been always a significant concern. Since it is inevitable to use the FIB technique, the improvement of efficiency is a key point. Traditional TEM sample preparation with FIB was routinely implemented on a single sample each time. Aiming at cost efficiency, a new pre-thinning technique for batch sample preparation was developed in this paper. The present proposal combines the sample preparation techniques with multi-samples thinning, cross-section scanning electron microscopy (SEM, wedge cutting, FIB and other sample pre-thinning techniques. The new pre-thinning technique is to prepare an edge TEM sample on a grinding and polishing fixture with a slant surface. The thickness of the wedges sample can be measured to 1∼2 μm under optical microscope. Therefore, this fixture is superior to the traditional optical method of estimating the membrane thickness. Moreover, by utilizing a multi-sample holding fixture, more samples can be pre-thinned simultaneously, which significantly improved the productivity of TEM sample preparation.

  18. Procedure for the preparation of tritium-labelled insulins. Verfahren zur Herstellung von Tritium-markierten Insulinen

    Energy Technology Data Exchange (ETDEWEB)

    Bienert, M; Haensicke, A; Beyermann, M; Kaufmann, K D; Oehlke, J; Klauschenz, E; Bespalowa, S; Titov, M; Pleiss, U

    1986-12-17

    This invention is concerned with a procedure for the preparation of specific /sup 3/H-labelled insulins with sequences of human, bovine or porcine insulins and without simultaneous chemical modifications of the insulin. On the basis of this procedure a /sup 3/H/sub 2/-Typ (B26)-insulin can be obtained in good yield and purity with a specific radioactivity appropriate to biopharmaceutical and pharmacokinetic purposes in medicine and pharmaceutical industry, resp.

  19. An efficient preparative procedure for main flavonoids from the peel of Trichosanthes kirilowii Maxim. using polyamide resin followed by semi-preparative high performance liquid chromatography.

    Science.gov (United States)

    Li, Aifeng; Sun, Ailing; Liu, Renmin; Zhang, Yongqing; Cui, Jichun

    2014-08-15

    In this study, a simple and efficient preparative procedure was developed for preparation of seven flavonoids from the peel of Trichosanthes kirilowii Maxim. using polyamide resin followed by semi-preparative high performance liquid chromatography (SPHPLC). First, the ethyl acetate fraction from the peel of T. kirilowii Maxim. obtained "prefractionation" using polyamide resin, which yielded two subfractions. And then the two subfractions were isolated by SPHPLC with an isocratic elution of methanol-water. Finally, seven known flavonoids were purified from 35 g of ethyl acetate extract including quercetin-3-O-[α-l-rhamnose (1→2)-β-d-glucopyranosyl]-5-O-β-d-glucopyranoside (19 mg), quercetin-3-O-rutinoside (24 mg), apigenin-7-O-β-d-glucopyranoside (10mg), diosmetin-7-O-β-d-glucopyranoside (45 mg), luteolin (21 mg), apigenin (15 mg), and diosmetin (56 mg). The purities of the compounds were determined by HPLC and the chemical structures were confirmed by UV and NMR analysis. In the present study, a simple, effective, and rapid procedure was established for preparative separation of multiple components from the peel of T. kirilowii Maxim. Furthermore, it was scalable and economical, so it was a promising basis for large-scale preparation of flavonoids from other plant extracts. Copyright © 2014. Published by Elsevier B.V.

  20. Automated injection of a radioactive sample for preparative HPLC with feedback control

    International Nuclear Information System (INIS)

    Iwata, Ren; Yamazaki, Shigeki

    1990-01-01

    The injection of a radioactive reaction mixture into a preparative HPLC column has been automated with computer control for rapid purification of routinely prepared positron emitting radiopharmaceuticals. Using pneumatic valves, a motor-driven pump and a liquid level sensor, two intelligent injection methods for the automation were compared with regard to efficient and rapid sample loading into a 2 mL loop of the 6-way valve. One, a precise but rather slow method, was demonstrated to be suitable for purification of 18 F-radiopharmaceuticals, while the other, due to its rapid operation, was more suitable for 11 C-radiopharmaceuticals. A sample volume of approx 0.5 mL can be injected onto a preparative HPLC column with over 90% efficiency with the present automated system. (author)

  1. The effectiveness of drama therapy on preparation for diagnostic and therapeutic procedures in children suffering from cancer

    Directory of Open Access Journals (Sweden)

    Ľubica Ilievová

    2015-10-01

    Full Text Available Introduction: The integral part of the treatment of pediatric oncological patients is a range of diagnostic and therapeutic procedures. These procedures are often associated with the fear and anxiety of the suffering child. We investigated whether a psychological preparation through drama therapy and the therapeutic puppet may reduce the anxiety related to diagnostic and therapeutic procedures in the preschool or early school children suffering from cancer.Methods: Twenty consecutive pediatric patients of preschool and early school age, with the diagnosis of lymphoblastic leukemia, were included in the study. The patients were alternatingly assigned to experimental or control group, and subjected or not subjected to drama therapy, respectively. We measured the changes in heart rate, blood pressure and respiratory rate as indicators of anxiety and fear, before and after the diagnostic or therapeutic procedures.Results: Heart rate, blood pressure, and respiratory rate in pediatric oncological patients before and after the diagnostic or therapeutic procedure were significantly lower in the experimental group of patients.Conclusion: Our results show that psychological preparation using drama therapy and therapeutic puppet reduced the fear and anxiety related to diagnostic or therapeutic procedures in pediatric oncological patients.Key words: drama therapy; therapeutic puppet; children; oncology; psychology 

  2. PREPARATION OF MORTARS FOR RESTORATION OF ARCHITECTURAL MONUMENTS

    Directory of Open Access Journals (Sweden)

    TEREZA TRIBULOVÁ

    2012-09-01

    Full Text Available Mortar mixtures were prepared considering the microscopic observation, granulometric analysis, mercury porosimetry, XRD analysis, thermogravimetric and differential thermal analysis of the original plaster. Two series of lime mortar samples containing identical mixture of aggregates and admixtures but varying in the kind of a lime binder were prepared. In addition, the sample series varied in the ratio between mixing aggregate and binder. Prepared test bodies were subjected to accelerated carbonation process. Carbonated samples were characterized by the measurement of compressive strength, open porosity, water absorption and resistance to salt crystallization. The samples were also again compared with the original plaster by optical microscopy and XRD analysis. Based on the results of analyses of the original plasters and prepared samples of repair mortar the sample containing lime slurry with the mixture of aggregates in the mixing ratio of 1 : 2 was recommended for the restoration procedure.

  3. Sample preparation and fractionation for proteome analysis and cancer biomarker discovery by mass spectrometry.

    Science.gov (United States)

    Ahmed, Farid E

    2009-03-01

    Sample preparation and fractionation technologies are one of the most crucial processes in proteomic analysis and biomarker discovery in solubilized samples. Chromatographic or electrophoretic proteomic technologies are also available for separation of cellular protein components. There are, however, considerable limitations in currently available proteomic technologies as none of them allows for the analysis of the entire proteome in a simple step because of the large number of peptides, and because of the wide concentration dynamic range of the proteome in clinical blood samples. The results of any undertaken experiment depend on the condition of the starting material. Therefore, proper experimental design and pertinent sample preparation is essential to obtain meaningful results, particularly in comparative clinical proteomics in which one is looking for minor differences between experimental (diseased) and control (nondiseased) samples. This review discusses problems associated with general and specialized strategies of sample preparation and fractionation, dealing with samples that are solution or suspension, in a frozen tissue state, or formalin-preserved tissue archival samples, and illustrates how sample processing might influence detection with mass spectrometric techniques. Strategies that dramatically improve the potential for cancer biomarker discovery in minimally invasive, blood-collected human samples are also presented.

  4. Matrix-assisted laser desorption/ionization sample preparation optimization for structural characterization of poly(styrene-co-pentafluorostyrene) copolymers

    International Nuclear Information System (INIS)

    Tisdale, Evgenia; Kennedy, Devin; Wilkins, Charles

    2014-01-01

    Graphical abstract: -- Highlights: •We optimized sample preparation for MALDI TOF poly(styrene-copentafluorostyrene) co-polymers. •Influence of matrix choice was investigated. •Influence of matrix/analyte ratio was examined. •Influence of analyte/salt ratio (for Ag+ salt) was studied. -- Abstract: The influence of the sample preparation parameters (the choice of the matrix, matrix:analyte ratio, salt:analyte ratio) was investigated and optimal conditions were established for the MALDI time-of-flight mass spectrometry analysis of the poly(styrene-co-pentafluorostyrene) copolymers. These were synthesized by atom transfer radical polymerization. Use of 2,5-dihydroxybenzoic acid as matrix resulted in spectra with consistently high ion yields for all matrix:analyte:salt ratios tested. The optimized MALDI procedure was successfully applied to the characterization of three copolymers obtained by varying the conditions of polymerization reaction. It was possible to establish the nature of the end groups, calculate molecular weight distributions, and determine the individual length distributions for styrene and pentafluorostyrene monomers, contained in the resulting copolymers. Based on the data obtained, it was concluded that individual styrene chain length distributions are more sensitive to the change in the composition of the catalyst (the addition of small amount of CuBr 2 ) than is the pentafluorostyrene component distribution

  5. Matrix-assisted laser desorption/ionization sample preparation optimization for structural characterization of poly(styrene-co-pentafluorostyrene) copolymers

    Energy Technology Data Exchange (ETDEWEB)

    Tisdale, Evgenia; Kennedy, Devin; Wilkins, Charles, E-mail: cwilkins@uark.edu

    2014-01-15

    Graphical abstract: -- Highlights: •We optimized sample preparation for MALDI TOF poly(styrene-copentafluorostyrene) co-polymers. •Influence of matrix choice was investigated. •Influence of matrix/analyte ratio was examined. •Influence of analyte/salt ratio (for Ag+ salt) was studied. -- Abstract: The influence of the sample preparation parameters (the choice of the matrix, matrix:analyte ratio, salt:analyte ratio) was investigated and optimal conditions were established for the MALDI time-of-flight mass spectrometry analysis of the poly(styrene-co-pentafluorostyrene) copolymers. These were synthesized by atom transfer radical polymerization. Use of 2,5-dihydroxybenzoic acid as matrix resulted in spectra with consistently high ion yields for all matrix:analyte:salt ratios tested. The optimized MALDI procedure was successfully applied to the characterization of three copolymers obtained by varying the conditions of polymerization reaction. It was possible to establish the nature of the end groups, calculate molecular weight distributions, and determine the individual length distributions for styrene and pentafluorostyrene monomers, contained in the resulting copolymers. Based on the data obtained, it was concluded that individual styrene chain length distributions are more sensitive to the change in the composition of the catalyst (the addition of small amount of CuBr{sub 2}) than is the pentafluorostyrene component distribution.

  6. Integrated preservation and sample clean up procedures for studying water ingestion by recreational swimmers via urinary biomarker determination.

    Science.gov (United States)

    Cantú, Ricardo; Shoemaker, Jody A; Kelty, Catherine A; Wymer, Larry J; Behymer, Thomas D; Dufour, Alfred P; Magnuson, Matthew L

    2017-08-22

    The use of cyanuric acid as a biomarker for ingestion of swimming pool water may lead to quantitative knowledge of the volume of water ingested during swimming, contributing to a better understanding of disease resulting from ingestion of environmental contaminants. When swimming pool water containing chlorinated cyanurates is inadvertently ingested, cyanuric acid is excreted quantitatively within 24 h as a urinary biomarker of ingestion. Because the volume of water ingested can be quantitatively estimated by calculation from the concentration of cyanuric acid in 24 h urine samples, a procedure for preservation, cleanup, and analysis of cyanuric acid was developed to meet the logistical demands of large scale studies. From a practical stand point, urine collected from swimmers cannot be analyzed immediately, given requirements of sample collection, shipping, handling, etc. Thus, to maintain quality control to allow confidence in the results, it is necessary to preserve the samples in a manner that ensures as quantitative analysis as possible. The preservation and clean-up of cyanuric acid in urine is complicated because typical approaches often are incompatible with the keto-enol tautomerization of cyanuric acid, interfering with cyanuric acid sample preparation, chromatography, and detection. Therefore, this paper presents a novel integration of sample preservation, clean-up, chromatography, and detection to determine cyanuric acid in 24 h urine samples. Fortification of urine with cyanuric acid (0.3-3.0 mg/L) demonstrated accuracy (86-93% recovery) and high reproducibility (RSD urine suggested sufficient cyanuric acid stability for sample collection procedures, while longer holding times suggested instability of the unpreserved urine. Preserved urine exhibited a loss of around 0.5% after 22 days at refrigerated storage conditions of 4 °C. Published by Elsevier B.V.

  7. Electrodeposition as an alternate method for preparation of environmental samples for iodide by AMS

    Energy Technology Data Exchange (ETDEWEB)

    Adamic, M.L., E-mail: Mary.Adamic@inl.gov [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States); Lister, T.E.; Dufek, E.J.; Jenson, D.D.; Olson, J.E. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States); Vockenhuber, C. [Laboratory of Ion Beam Physics, ETH Zurich, Otto-Stern-Weg 5, 8093 Zurich (Switzerland); Watrous, M.G. [Idaho National Laboratory, P.O. Box 1625, Idaho Falls, ID 83402 (United States)

    2015-10-15

    This paper presents an evaluation of an alternate method for preparing environmental samples for {sup 129}I analysis by accelerator mass spectrometry (AMS) at Idaho National Laboratory. The optimal sample preparation method is characterized by ease of preparation, capability of processing very small quantities of iodide, and ease of loading into a cathode. Electrodeposition of iodide on a silver wire was evaluated using these criteria. This study indicates that the electrochemically-formed silver iodide deposits produce ion currents similar to those from precipitated silver iodide for the same sample mass. Precipitated silver iodide samples are usually mixed with niobium or silver powder prior to loading in a cathode. Using electrodeposition, the silver is already mixed with the sample and can simply be picked up with tweezers, placed in the sample die, and pressed into a cathode. The major advantage of this method is that the silver wire/electrodeposited silver iodide is much easier to load into a cathode.

  8. Electrodeposition as an alternate method for preparation of environmental samples for iodide by AMS

    International Nuclear Information System (INIS)

    Adamic, M.L.; Lister, T.E.; Dufek, E.J.; Jenson, D.D.; Olson, J.E.; Vockenhuber, C.; Watrous, M.G.

    2015-01-01

    This paper presents an evaluation of an alternate method for preparing environmental samples for "1"2"9I analysis by accelerator mass spectrometry (AMS) at Idaho National Laboratory. The optimal sample preparation method is characterized by ease of preparation, capability of processing very small quantities of iodide, and ease of loading into a cathode. Electrodeposition of iodide on a silver wire was evaluated using these criteria. This study indicates that the electrochemically-formed silver iodide deposits produce ion currents similar to those from precipitated silver iodide for the same sample mass. Precipitated silver iodide samples are usually mixed with niobium or silver powder prior to loading in a cathode. Using electrodeposition, the silver is already mixed with the sample and can simply be picked up with tweezers, placed in the sample die, and pressed into a cathode. The major advantage of this method is that the silver wire/electrodeposited silver iodide is much easier to load into a cathode.

  9. A high-throughput sample preparation method for cellular proteomics using 96-well filter plates.

    Science.gov (United States)

    Switzar, Linda; van Angeren, Jordy; Pinkse, Martijn; Kool, Jeroen; Niessen, Wilfried M A

    2013-10-01

    A high-throughput sample preparation protocol based on the use of 96-well molecular weight cutoff (MWCO) filter plates was developed for shotgun proteomics of cell lysates. All sample preparation steps, including cell lysis, buffer exchange, protein denaturation, reduction, alkylation and proteolytic digestion are performed in a 96-well plate format, making the platform extremely well suited for processing large numbers of samples and directly compatible with functional assays for cellular proteomics. In addition, the usage of a single plate for all sample preparation steps following cell lysis reduces potential samples losses and allows for automation. The MWCO filter also enables sample concentration, thereby increasing the overall sensitivity, and implementation of washing steps involving organic solvents, for example, to remove cell membranes constituents. The optimized protocol allowed for higher throughput with improved sensitivity in terms of the number of identified cellular proteins when compared to an established protocol employing gel-filtration columns. © 2013 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  10. Improved sample preparation and counting techniques for enhanced tritium measurement sensitivity

    Science.gov (United States)

    Moran, J.; Aalseth, C.; Bailey, V. L.; Mace, E. K.; Overman, C.; Seifert, A.; Wilcox Freeburg, E. D.

    2015-12-01

    Tritium (T) measurements offer insight to a wealth of environmental applications including hydrologic tracking, discerning ocean circulation patterns, and aging ice formations. However, the relatively short half-life of T (12.3 years) limits its effective age dating range. Compounding this limitation is the decrease in atmospheric T content by over two orders of magnitude (from 1000-2000 TU in 1962 to testing in the 1960's. We are developing sample preparation methods coupled to direct counting of T via ultra-low background proportional counters which, when combined, offer improved T measurement sensitivity (~4.5 mmoles of H2 equivalent) and will help expand the application of T age dating to smaller sample sizes linked to persistent environmental questions despite the limitations above. For instance, this approach can be used to T date ~ 2.2 mmoles of CH4 collected from sample-limited systems including microbial communities, soils, or subsurface aquifers and can be combined with radiocarbon dating to distinguish the methane's formation age from C age in a system. This approach can also expand investigations into soil organic C where the improved sensitivity will permit resolution of soil C into more descriptive fractions and provide direct assessments of the stability of specific classes of organic matter in soils environments. We are employing a multiple step sample preparation system whereby organic samples are first combusted with resulting CO2 and H2O being used as a feedstock to synthesize CH4. This CH4 is mixed with Ar and loaded directly into an ultra-low background proportional counter for measurement of T β decay in a shallow underground laboratory. Analysis of water samples requires only the addition of geologic CO2 feedstock with the sample for methane synthesis. The chemical nature of the preparation techniques enable high sample throughput with only the final measurement requiring T decay with total sample analysis time ranging from 2 -5 weeks

  11. Analytical procedures for determining Pb and Sr isotopic compositions in water samples by ID-TIMS

    Directory of Open Access Journals (Sweden)

    Veridiana Martins

    2008-01-01

    Full Text Available Few articles deal with lead and strontium isotopic analysis of water samples. The aim of this study was to define the chemical procedures for Pb and Sr isotopic analyses of groundwater samples from an urban sedimentary aquifer. Thirty lead and fourteen strontium isotopic analyses were performed to test different analytical procedures. Pb and Sr isotopic ratios as well as Sr concentration did not vary using different chemical procedures. However, the Pb concentrations were very dependent on the different procedures. Therefore, the choice of the best analytical procedure was based on the Pb results, which indicated a higher reproducibility from samples that had been filtered and acidified before the evaporation, had their residues totally dissolved, and were purified by ion chromatography using the Biorad® column. Our results showed no changes in Pb ratios with the storage time.

  12. Preparation and application of radioactive soil samples for intercomparison

    International Nuclear Information System (INIS)

    Gao Zequan; Li Zhou; Li Pengxiang; Wang Ruijun; Ren Xiaona

    2014-01-01

    This article summarized the preparation process and intercomparison results of the simulated environmental radioactive soil samples. The components of the matrix were: SiO 2 , Al 2 O 3 , Fe 2 O 3 , MgO, CaO, NaCl, KCl and TiO 2 . All of the components were milled, oven-dried, sieved and then blended together. The homogeneity test was according to GB 15000. 5-1994, and no significant differences were observed. The 3 H analysis soils were spiked natural soils with the moisture content of 15%. Eight laboratories attended this intercomparison. The results proves that the preparation of the simulated soils were suitable for the inter-laboratories comparison. (authors)

  13. Solvent Front Position Extraction procedure with thin-layer chromatography as a mode of multicomponent sample preparation for quantitative analysis by instrumental technique.

    Science.gov (United States)

    Klimek-Turek, A; Sikora, E; Dzido, T H

    2017-12-29

    A concept of using thin-layer chromatography to multicomponent sample preparation for quantitative determination of solutes followed by instrumental technique is presented. Thin-layer chromatography (TLC) is used to separate chosen substances and their internal standard from other components (matrix) and to form a single spot/zone containing them at the solvent front position. The location of the analytes and internal standard in the solvent front zone allows their easy extraction followed by quantitation by HPLC. Copyright © 2017 Elsevier B.V. All rights reserved.

  14. Sample Preparation Strategies for the Effective Quantitation of Hydrophilic Metabolites in Serum by Multi-Targeted HILIC-MS/MS

    Directory of Open Access Journals (Sweden)

    Elisavet Tsakelidou

    2017-03-01

    Full Text Available The effect of endogenous interferences of serum in multi-targeted metabolite profiling HILIC-MS/MS analysis was investigated by studying different sample preparation procedures. A modified QuEChERS dispersive SPE protocol, a HybridSPE protocol, and a combination of liquid extraction with protein precipitation were compared to a simple protein precipitation. Evaluation of extraction efficiency and sample clean-up was performed for all methods. SPE sorbent materials tested were found to retain hydrophilic analytes together with endogenous interferences, thus additional elution steps were needed. Liquid extraction was not shown to minimise matrix effects. In general, it was observed that a balance should be reached in terms of recovery, efficient clean-up, and sample treatment time when a wide range of metabolites are analysed. A quick step for removing phospholipids prior to the determination of hydrophilic endogenous metabolites is required, however, based on the results from the applied methods, further studies are needed to achieve high recoveries for all metabolites.

  15. Should the mass of a nanoferrite sample prepared by autocombustion method be considered as a realistic preparation parameter?

    Energy Technology Data Exchange (ETDEWEB)

    Wahba, Adel Maher, E-mail: adel.mousa@f-eng.tanta.edu.eg [Department of Engineering Physics and Mathematics, Faculty of Engineering, Tanta University (Egypt); Mohamed, Mohamed Bakr [Ain shams University, Faculty of Science, Physics Department, Cairo (Egypt)

    2017-02-15

    Detectable variations in structural, elastic and magnetic properties have been reported depending on the mass of the cobalt nanoferrite sample prepared by citrate autocombustion method. Heat released during the autocombustion process and its duration are directly proportional to the mass to be prepared, and is thus expected to affect both the crystallite size and the cation distribution giving rise to the reported variations in microstrain, magnetization, and coercivity. Formation of a pure spinel phase has been validated using X-ray diffraction patterns (XRD) and Fourier-transform infrared (FTIR) spectra. Crystallite sizes obtained from Williamson-Hall (W-H) method range from 28–87 nm, being further supported by images of high-resolution transmission electron microscope (HRTEM). Saturation magnetization and coercivity deduced from M-H hysteresis loops show a clear correlation with the cation distribution, which was proposed on the basis of experimentally obtained data of XRD, VSM, and IR. Elastic parameters have been estimated using the cation distribution and FTIR data, with a resulting trend quite opposite to that of the lattice parameter. - Highlights: • Samples with different masses of CoFe{sub 2}O{sub 4} were prepared by autocombustion method. • XRD and IR data confirmed a pure spinel cubic structure for all samples. • Structural and magnetic properties show detectable changes with the mass prepared. • Cation distribution was suggested from experimental data of XRD, IR, and M-H loops.

  16. Experiences from Refurbishment of Metallography Hot Cells and Application of a New Preparation Concept for Materialography Samples

    International Nuclear Information System (INIS)

    Oberlander, B. C.; Espeland, M.; Solum, N. O.

    2001-01-01

    After more than 30 years of operation the lead shielded metallography hot cells needed a basic renewal and modernisation not least of the specimen preparation equipment. Preparation in hot cells of radioactive samples for metallography and ceramography is challenging and time consuming. It demands a special design and quality of all in-cell equipment and skill and patience from the operator. Essentials in the preparation process are: simplicity and reliability of the machines, and a good quality, reproducibility and efficiency in performance. Desirable is process automation, flexibility and an alara amounto of radioactive waste produced per sample prepared. State of the art preparation equipment for materialography seems to meet most of the demands, however, it cannot be used in hot cells without modifications. Therefore. IFE and Struers in Copenhagen modified a standard model of a Strues precision cutting machine and a microprocessor controlled grinding and polishing machine for Hot Cell application. Hot cell utilisation of the microcomputer controlled grinding and polishing machine and the existing automatic dosing equipment made the task of preparing radioactive samples more attractive. The new grinding and polishing system for hot cells provides good sample preparation quality and reproductibility at reduced preparation time and reduced amount of contaminated waste produced per sample prepared. the sample materials examined were irradiated cladding materials and fuels

  17. Radiocarbon accelerator mass spectrometry (AMS) sample preparation laboratory in Brazil

    International Nuclear Information System (INIS)

    Macario, Kita D.; Gomes, Paulo R. S.; Anjos, Roberto M. dos; Linares, Roberto; Queiroz, Eduardo; Oliveira, Fabiana M. de; Cardozo, Laio; Carvalho, Carla R.A.

    2011-01-01

    Full text: For decades Accelerator Mass Spectrometry has been widely used for radiocarbon measurements all over the world with application in several fields of science from archaeology to geosciences. This technique provides ultrasensitive analysis of reduced size samples or even specific compounds since sample atoms are accelerated to high energies and measured using nuclear particle detectors. Sample preparation is extremely important for accurate radiocarbon measurement and includes chemical pre-treatment to remove all possible contaminants. For beam extraction in the accelerator ion source, samples are usually converted to graphite. In this work we report a new radiocarbon sample preparation facility installed at the Physics Institute of Universidade Federal Fluminense (UFF), in Brazil. At the Nuclear Chronology Laboratory (LACRON) samples are chemically treated and converted to carbon dioxide by hydrolysis or combustion. A stainless steel based vacuum line was constructed for carbon dioxide separation and graphitization is performed in sealed quartz tubes in a muffle oven. Successful graphite production is important to provide stable beam currents and to minimize isotopic fractionation. Performance tests for graphite production are currently under way and isotopic analysis will soon be possible with the acquisition of a Single Stage AMS System by our group. The Single Stage Accelerator produced by National Electrostatic Corporation is a 250 kV air insulated accelerator especially constructed to measure the amount of 14 C in small modern graphite samples to a precision of 0.3 % or better. With the installation of such equipment in the first half of 2012, UFF will be ready to perform the 14C -AMS technique. (author)

  18. Evaluation of cell wall preparations for proteomics: a new procedure for purifying cell walls from Arabidopsis hypocotyls

    Directory of Open Access Journals (Sweden)

    Canut Hervé

    2006-05-01

    Full Text Available Abstract Background The ultimate goal of proteomic analysis of a cell compartment should be the exhaustive identification of resident proteins; excluding proteins from other cell compartments. Reaching such a goal closely depends on the reliability of the isolation procedure for the cell compartment of interest. Plant cell walls possess specific difficulties: (i the lack of a surrounding membrane may result in the loss of cell wall proteins (CWP during the isolation procedure, (ii polysaccharide networks of cellulose, hemicelluloses and pectins form potential traps for contaminants such as intracellular proteins. Several reported procedures to isolate cell walls for proteomic analyses led to the isolation of a high proportion (more than 50% of predicted intracellular proteins. Since isolated cell walls should hold secreted proteins, one can imagine alternative procedures to prepare cell walls containing a lower proportion of contaminant proteins. Results The rationales of several published procedures to isolate cell walls for proteomics were analyzed, with regard to the bioinformatic-predicted subcellular localization of the identified proteins. Critical steps were revealed: (i homogenization in low ionic strength acid buffer to retain CWP, (ii purification through increasing density cushions, (iii extensive washes with a low ionic strength acid buffer to retain CWP while removing as many cytosolic proteins as possible, and (iv absence of detergents. A new procedure was developed to prepare cell walls from etiolated hypocotyls of Arabidopsis thaliana. After salt extraction, a high proportion of proteins predicted to be secreted was released (73%, belonging to the same functional classes as proteins identified using previously described protocols. Finally, removal of intracellular proteins was obtained using detergents, but their amount represented less than 3% in mass of the total protein extract, based on protein quantification. Conclusion The

  19. TruSeq Stranded mRNA and Total RNA Sample Preparation Kits

    Science.gov (United States)

    Total RNA-Seq enabled by ribosomal RNA (rRNA) reduction is compatible with formalin-fixed paraffin embedded (FFPE) samples, which contain potentially critical biological information. The family of TruSeq Stranded Total RNA sample preparation kits provides a unique combination of unmatched data quality for both mRNA and whole-transcriptome analyses, robust interrogation of both standard and low-quality samples and workflows compatible with a wide range of study designs.

  20. Preparation of pure TiO2 sorption material

    International Nuclear Information System (INIS)

    Špendlíková, Irena; Raindl, Jakub; Němec, Mojmír

    2013-01-01

    Among the natural or anthropogenic radionuclides of very low concentrations nowadays measured in environmental samples, the radionuclide of 236 U has been recently included. In these ultra-trace analyses, the purity of sorption materials is very important and the traditional preparation procedures have to be optimized to minimize possible contamination. In the case of the determination of natural concentration of 236 U ( 236 U/ 238 U ∼ 10 -10 - 10 -14 ), the sample treatment procedure has to be modified in order to eliminate possible contamination from anthropogenic 236 U that may result even in more than ten thousand times higher 236 U/ 238 U ratios. Many inorganic and organic materials have been proposed for the extraction of uranium. However, only several of them are suitable for the uranium sorption from the solutions of low uranium concentration, but relatively high salt content, such as fresh water, sea water etc. At the same time they have to meet other limiting parameters such as fast kinetics, chemical stability, and low costs. Among the inorganic sorption materials, titanium dioxide has been studied for years with promising results. Titanium dioxides can be prepared via the hydrolysis of titanium compounds, either inorganic salts or organic derivatives, but their properties strongly depend on the preparation conditions. In classical procedures, titanium dioxides are prepared from commercial inorganic salts, such as sulphates or chlorides, or even from industrial intermediates of the titanium white production. Typically, the resulting titanium dioxides are contaminated with uranium already from the origin. Assuming that most organic compounds do not contain uranium and that it is possible to find 'uranium free' water, titanium dioxide free of uranium contamination could be prepared by the hydrolysis of organic titanium derivatives. The aim of this study was to find a suitable way of pure titanium dioxide preparation and to optimize the preparation

  1. Infrared biospectroscopy for a fast qualitative evaluation of sample preparation in metabolomics.

    Science.gov (United States)

    Kuligowski, Julia; Pérez-Guaita, David; Escobar, Javier; Lliso, Isabel; de la Guardia, Miguel; Lendl, Bernhard; Vento, Máximo; Quintás, Guillermo

    2014-09-01

    Liquid chromatography-mass spectrometry (LC-MS) has been increasingly used in biomedicine to study the dynamic metabolomic responses of biological systems under different physiological or pathological conditions. To obtain an integrated snapshot of the system, metabolomic methods in biomedicine typically analyze biofluids (e.g. plasma) that require clean-up before being injected into LC-MS systems. However, high resolution LC-MS is costly in terms of resources required for sample and data analysis and care must be taken to prevent chemical (e.g. ion suppression) or statistical artifacts. Because of that, the effect of sample preparation on the metabolomic profile during metabolomic method development is often overlooked. This work combines an Attenuated Total Reflectance-Fourier transform infrared (ATR-FTIR) and a multivariate exploratory data analysis for a cost-effective qualitative evaluation of major changes in sample composition during sample preparation. ATR-FTIR and LC-time of flight mass spectrometry (TOFMS) data from the analysis of a set of plasma samples precipitated using acetonitrile, methanol and acetone performed in parallel were used as a model example. Biochemical information obtained from the analysis of the ATR-FTIR and LC-TOFMS data was thoroughly compared to evaluate the strengths and shortcomings of FTIR biospectroscopy for assessing sample preparation in metabolomics studies. Results obtained show the feasibility of ATR-FTIR for the evaluation of major trends in the plasma composition changes among different sample pretreatments, providing information in terms of e.g., amino acids, proteins, lipids and carbohydrates overall contents comparable to those found by LC-TOFMS. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Application of bias correction methods to improve U{sub 3}Si{sub 2} sample preparation for quantitative analysis by WDXRF

    Energy Technology Data Exchange (ETDEWEB)

    Scapin, Marcos A.; Guilhen, Sabine N.; Azevedo, Luciana C. de; Cotrim, Marycel E.B.; Pires, Maria Ap. F., E-mail: mascapin@ipen.br, E-mail: snguilhen@ipen.br, E-mail: lvsantana@ipen.br, E-mail: mecotrim@ipen.br, E-mail: mapires@ipen.br [Instituto de Pesquisas Energéticas e Nucleares (IPEN/CNEN-SP), São Paulo, SP (Brazil)

    2017-07-01

    The determination of silicon (Si), total uranium (U) and impurities in uranium-silicide (U{sub 3}Si{sub 2}) samples by wavelength dispersion X-ray fluorescence technique (WDXRF) has been already validated and is currently implemented at IPEN's X-Ray Fluorescence Laboratory (IPEN-CNEN/SP) in São Paulo, Brazil. Sample preparation requires the use of approximately 3 g of H{sub 3}BO{sub 3} as sample holder and 1.8 g of U{sub 3}Si{sub 2}. However, because boron is a neutron absorber, this procedure precludes U{sub 3}Si{sub 2} sample's recovery, which, in time, considering routinely analysis, may account for significant unusable uranium waste. An estimated average of 15 samples per month are expected to be analyzed by WDXRF, resulting in approx. 320 g of U{sub 3}Si{sub 2} that would not return to the nuclear fuel cycle. This not only impacts in production losses, but generates another problem: radioactive waste management. The purpose of this paper is to present the mathematical models that may be applied for the correction of systematic errors when H{sub 3}BO{sub 3} sample holder is substituted by cellulose-acetate {[C_6H_7O_2(OH)_3_-_m(OOCCH_3)m], m = 0∼3}, thus enabling U{sub 3}Si{sub 2} sample’s recovery. The results demonstrate that the adopted mathematical model is statistically satisfactory, allowing the optimization of the procedure. (author)

  3. Nevada Applied Ecology Group procedures handbook for environmental transuranics

    International Nuclear Information System (INIS)

    White, M.G.; Dunaway, P.B.

    1976-10-01

    The activities of the Nevada Applied Ecology Group (NAEG) integrated research studies of environmental plutonium and other transuranics at the Nevada Test Site have required many standardized field and laboratory procedures. These include sampling techniques, collection and preparation, radiochemical and wet chemistry analysis, data bank storage and reporting, and statistical considerations for environmental samples of soil, vegetation, resuspended particles, animals, and other biological material. This document, printed in two volumes, includes most of the Nevada Applied Ecology Group standard procedures, with explanations as to the specific applications involved in the environmental studies. Where there is more than one document concerning a procedure, it has been included to indicate special studies or applications more complex than the routine standard sampling procedures utilized

  4. Nevada Applied Ecology Group procedures handbook for environmental transuranics

    International Nuclear Information System (INIS)

    White, M.G.; Dunaway, P.B.

    1976-10-01

    The activities of the Nevada Applied Ecology Group (NAEG) integrated research studies of environmental plutonium and other transuranics at the Nevada Test Site have required many standardized field and laboratory procedures. These include sampling techniques, collection and preparation, radiochemical and wet chemistry analysis, data bank storage and reporting, and statistical considerations for environmental samples of soil, vegetation, resuspended particles, animals, and others. This document, printed in two volumes, includes most of the Nevada Applied Ecology Group standard procedures, with explanations as to the specific applications involved in the environmental studies. Where there is more than one document concerning a procedure, it has been included to indicate special studies or applications perhaps more complex than the routine standard sampling procedures utilized

  5. Highly oriented Bi-system bulk sample prepared by a decomposition-crystallization process

    International Nuclear Information System (INIS)

    Xi Zhengping; Zhou Lian; Ji Chunlin

    1992-01-01

    A decomposition-crystallization method, preparing highly oriented Bi-system bulk sample is reported. The effects of processing parameter, decomposition temperature, cooling rate and post-treatment condition on texture and superconductivity are investigated. The method has successfully prepared highly textured Bi-system bulk samples. High temperature annealing does not destroy the growing texture, but the cooling rate has some effect on texture and superconductivity. Annealing in N 2 /O 2 atmosphere can improve superconductivity of the textured sample. The study on the superconductivity of the Bi(Pb)-Sr-Ca-Cu-O bulk material has been reported in numerous papers. The research on J c concentrates on the tape containing the 2223 phase, with very few studies on the J c of bulk sample. The reason for the lack of studies is that the change of superconducting phases at high temperatures has not been known. The authors have reported that the 2212 phase incongruently melted at about 875 degrees C and proceeded to orient the c-axis perpendicular to the surface in the process of crystallization of the 2212 phase. Based on that result, a decomposition-crystallization method was proposed to prepare highly oriented Bi-system bulk sample. In this paper, the process is described in detail and the effects of processing parameters on texture and superconductivity are reported

  6. Microextraction by Packed Sorbent (MEPS and Solid-Phase Microextraction (SPME as Sample Preparation Procedures for the Metabolomic Profiling of Urine

    Directory of Open Access Journals (Sweden)

    Catarina Silva

    2014-01-01

    Full Text Available For a long time, sample preparation was unrecognized as a critical issue in the analytical methodology, thus limiting the performance that could be achieved. However, the improvement of microextraction techniques, particularly microextraction by packed sorbent (MEPS and solid-phase microextraction (SPME, completely modified this scenario by introducing unprecedented control over this process. Urine is a biological fluid that is very interesting for metabolomics studies, allowing human health and disease characterization in a minimally invasive form. In this manuscript, we will critically review the most relevant and promising works in this field, highlighting how the metabolomic profiling of urine can be an extremely valuable tool for the early diagnosis of highly prevalent diseases, such as cardiovascular, oncologic and neurodegenerative ones.

  7. X-ray diffraction without sample preparation: Proof-of-principle experiments

    International Nuclear Information System (INIS)

    Hansford, Graeme M.

    2013-01-01

    The properties of a novel X-ray diffraction (XRD) technique having very low sensitivity to the sample morphology were previously elucidated through theoretical considerations and model simulations (Hansford, 2011). This technique opens up the possibility of mineralogical analysis by XRD without sample preparation. Here, the results of proof-of-principle experimental tests are presented. Two sets of experiments were performed using a vacuum chamber equipped with an X-ray tube source, sample holder and charge-coupled detector. Firstly, a pressed-powder pellet of α-quartz was placed in three different positions relative to the X-ray source and detector. The changes in position represent gross sample movements which would be inconceivable in conventional XRD analysis. The resulting back-reflection energy-dispersive spectra show a very high degree of correspondence other than an overall intensity factor dependent on the distance between the sample and detector. Secondly, the back-reflection spectrum of an unprepared limestone hand specimen, having mm-scale surface morphology, was compared to the spectrum of a calcite pressed-powder pellet. The correspondence of the diffraction peaks in the spectra demonstrate that the limestone is comprised dominantly of calcite. In both cases, the claims of the earlier paper are fully supported by the results of these experimental tests. -- Highlights: • Proof-of-principle tests of a novel X-ray diffraction (XRD) method were conducted. • Very low sensitivity to sample position and orientation was demonstrated. • Insensitivity to sample morphology is inferred. • A simple analysis of an unprepared limestone hand specimen was performed. • This technique enables mineralogical analysis by XRD without sample preparation

  8. pH adjustment of human blood plasma prior to bioanalytical sample preparation

    NARCIS (Netherlands)

    Hendriks, G.; Uges, D. R. A.; Franke, J. P.

    2008-01-01

    pH adjustment in bioanalytical sample preparation concerning ionisable compounds is one of the most common sample treatments. This is often done by mixing an aliquot of the sample with a proper buffer adjusted to the proposed pH. The pH of the resulting mixture however, does not necessarily have to

  9. XRF analysis of mineralised samples

    International Nuclear Information System (INIS)

    Ahmedali, T.

    2002-01-01

    Full text: Software now supplied by instrument manufacturers has made it practical and convenient for users to analyse unusual samples routinely. Semiquantitative scanning software can be used for rapid preliminary screening of elements ranging from Carbon to Uranium, prior to assigning mineralised samples to an appropriate quantitative analysis routine. The general quality and precision of analytical results obtained from modern XRF spectrometers can be significantly enhanced by several means: a. Modifications in preliminary sample preparation can result in less contamination from crushing and grinding equipment. Optimised techniques of actual sample preparation can significantly increase precision of results. b. Employment of automatic data recording balances and the use of catch weights during sample preparation reduces technician time as well as weighing errors. * c. Consistency of results can be improved significantly by the use of appropriate stable drift monitors with a statistically significant content of the analyte d. A judicious selection of kV/mA combinations, analysing crystals, primary beam filters, collimators, peak positions, accurate background correction and peak overlap corrections, followed by the use of appropriate matrix correction procedures. e. Preventative maintenance procedures for XRF spectrometers and ancillary equipment, which can also contribute significantly to reducing instrument down times, are described. Examples of various facets of sample processing routines are given from the XRF spectrometer component of a multi-instrument analytical university facility, which provides XRF data to 17 Canadian universities. Copyright (2002) Australian X-ray Analytical Association Inc

  10. The role of graphene-based sorbents in modern sample preparation techniques.

    Science.gov (United States)

    de Toffoli, Ana Lúcia; Maciel, Edvaldo Vasconcelos Soares; Fumes, Bruno Henrique; Lanças, Fernando Mauro

    2018-01-01

    The application of graphene-based sorbents in sample preparation techniques has increased significantly since 2011. These materials have good physicochemical properties to be used as sorbent and have shown excellent results in different sample preparation techniques. Graphene and its precursor graphene oxide have been considered to be good candidates to improve the extraction and concentration of different classes of target compounds (e.g., parabens, polycyclic aromatic hydrocarbon, pyrethroids, triazines, and so on) present in complex matrices. Its applications have been employed during the analysis of different matrices (e.g., environmental, biological and food). In this review, we highlight the most important characteristics of graphene-based material, their properties, synthesis routes, and the most important applications in both off-line and on-line sample preparation techniques. The discussion of the off-line approaches includes methods derived from conventional solid-phase extraction focusing on the miniaturized magnetic and dispersive modes. The modes of microextraction techniques called stir bar sorptive extraction, solid phase microextraction, and microextraction by packed sorbent are discussed. The on-line approaches focus on the use of graphene-based material mainly in on-line solid phase extraction, its variation called in-tube solid-phase microextraction, and on-line microdialysis systems. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Sample preparation and characterization of technetium metal

    International Nuclear Information System (INIS)

    Minato, Kazuo; Serizawa, Hiroyuki; Fukuda, Kousaku; Itoh, Mitsuo

    1997-10-01

    Technetium-99 is a long-lived fission product with a half-life of about 2.1 x 10 5 years, which decays by β-emission. For the transmutation of 99 Tc, research on solid technetium was started. Technetium metal powder purchased was analyzed by X-ray diffraction, γ-ray spectrometry, and inductively coupled plasma-atomic emission spectrometry and -mass spectrometry. The lattice parameters obtained were agreed with the reported values. The metallic impurity was about 15 ppm, where aluminum and iron contributed mainly. No impurity nuclide with γ-emission was found. Using the technetium metal powder, button-, rod-, and disk-shaped samples of technetium metal were prepared by arc-melting technique. Thermal diffusivity of technetium metal was measured on a disk sample from room temperature to 1173 K by laser flash method. The thermal diffusivity decreased with increasing temperature though it was almost constant above 600 K. (author)

  12. Comparison of leach results from field and laboratory prepared samples

    International Nuclear Information System (INIS)

    Oblath, S.B.; Langton, C.A.

    1985-01-01

    The leach behavior of saltstone prepared in the laboratory agrees well with that from samples mixed in the field using the Littleford mixer. Leach rates of nitrates and cesium from the current reference formulation saltstone were compared. The laboratory samples were prepared using simulated salt solution; those in the field used Tank 50 decontaminated supernate. For both nitrate and cesium, the field and laboratory samples showed nearly identical leach rates for the first 30 to 50 days. For the remaining period of the test, the field samples showed higher leach rates with the maximum difference being less than a factor of three. Ruthenium and antimony were present in the Tank 50 supernate in known amounts. Antimony-125 was observed in the leachate and a fractional leach rate was calculated to be at least a factor of ten less than that of 137 Cs. No 106 Ru was observed in the leachate, and the release rate was not calculated. However, based on the detection limits for the analysis, the ruthenium leach rate must also be at least a factor of ten less than cesium. These data are the first measurements of the leach rates of Ru and Sb from saltstone. The nitrate leach rates for these samples were 5 x 10 -5 grams of nitrate per square cm per day after 100 days for the laboratory samples and after 200 days for the field samples. These values are consistent with the previously measured leach rates for reference formulation saltstone. The relative standard deviation in the leach rate is about 15% for the field samples, which all were produced from one batch of saltstone, and about 35% for the laboratory samples, which came from different batches. These are the first recorded estimates of the error in leach rates for saltstone

  13. Experience in treatment of hyperthyroidism with I-131 diagnosis, patient preparation and therapeutic procedure

    International Nuclear Information System (INIS)

    Zhongyun, Pan

    2003-01-01

    Treatment of hyperthyroidism with I-131 diagnosis is being performed after clinical diagnosis of thyrotoxicosis based on clinical manifestations of hypermetabolic state, serumT3 and T4 determination; medical preparation of patients and therapeutic procedure is obtained for better efficacy, relieve symptoms and prevent aggravation of thyrotoxicosis after I-131 treatment

  14. The NOSAMS sample preparation laboratory in the next millenium: Progress after the WOCE program

    International Nuclear Information System (INIS)

    Gagnon, Alan R.; McNichol, Ann P.; Donoghue, Joanne C.; Stuart, Dana R.; Reden, Karl von

    2000-01-01

    Since 1991, the primary charge of the National Ocean Sciences AMS (NOSAMS) facility at the Woods Hole Oceanographic Institution has been to supply high throughput, high precision AMS 14 C analyses for seawater samples collected as part of the World Ocean Circulation Experiment (WOCE). Approximately 13,000 samples taken as part of WOCE should be fully analyzed by the end of Y2K. Additional sample sources and techniques must be identified and incorporated if NOSAMS is to continue in its present operation mode. A trend in AMS today is the ability to routinely process and analyze radiocarbon samples that contain tiny amounts ( 14 C analysis has been recognized as a major facility goal. The installation of a new 134-position MC-SNICS ion source, which utilizes a smaller graphite target cartridge than presently used, is one step towards realizing this goal. New preparation systems constructed in the sample preparation laboratory (SPL) include an automated bank of 10 small-volume graphite reactors, an automated system to process organic carbon samples, and a multi-dimensional preparative capillary gas chromatograph (PCGC)

  15. Rapid immunohistochemical diagnosis of tobacco mosaic virus disease by microwave-assisted plant sample preparation

    Science.gov (United States)

    Zellnig, Günther; Möstl, Stefan; Zechmann, Bernd

    2013-01-01

    Immunoelectron microscopy is a powerful method to diagnose viral diseases and to study the distribution of the viral agent within plant cells and tissues. Nevertheless, current protocols for the immunological detection of viral diseases with transmission electron microscopy (TEM) in plants take between 3 and 6 days and are therefore not suited for rapid diagnosis of virus diseases in plants. In this study, we describe a method that allows rapid cytohistochemical detection of tobacco mosaic virus (TMV) in leaves of tobacco plants. With the help of microwave irradiation, sample preparation of the leaves was reduced to 90 min. After sample sectioning, virus particles were stained on the sections by immunogold labelling of the viral coat protein, which took 100 min. After investigation with the TEM, a clear visualization of TMV in tobacco cells was achieved altogether in about half a day. Comparison of gold particle density by image analysis revealed that samples prepared with the help of microwave irradiation yielded significantly higher gold particle density as samples prepared conventionally at room temperature. This study clearly demonstrates that microwave-assisted plant sample preparation in combination with cytohistochemical localization of viral coat protein is well suited for rapid diagnosis of plant virus diseases in altogether about half a day by TEM. PMID:23580761

  16. Protocols for the analytical characterization of therapeutic monoclonal antibodies. II - Enzymatic and chemical sample preparation.

    Science.gov (United States)

    Bobaly, Balazs; D'Atri, Valentina; Goyon, Alexandre; Colas, Olivier; Beck, Alain; Fekete, Szabolcs; Guillarme, Davy

    2017-08-15

    The analytical characterization of therapeutic monoclonal antibodies and related proteins usually incorporates various sample preparation methodologies. Indeed, quantitative and qualitative information can be enhanced by simplifying the sample, thanks to the removal of sources of heterogeneity (e.g. N-glycans) and/or by decreasing the molecular size of the tested protein by enzymatic or chemical fragmentation. These approaches make the sample more suitable for chromatographic and mass spectrometric analysis. Structural elucidation and quality control (QC) analysis of biopharmaceutics are usually performed at intact, subunit and peptide levels. In this paper, general sample preparation approaches used to attain peptide, subunit and glycan level analysis are overviewed. Protocols are described to perform tryptic proteolysis, IdeS and papain digestion, reduction as well as deglycosylation by PNGase F and EndoS2 enzymes. Both historical and modern sample preparation methods were compared and evaluated using rituximab and trastuzumab, two reference therapeutic mAb products approved by Food and Drug Administration (FDA) and European Medicines Agency (EMA). The described protocols may help analysts to develop sample preparation methods in the field of therapeutic protein analysis. Copyright © 2017 Elsevier B.V. All rights reserved.

  17. The NOSAMS sample preparation laboratory in the next millenium: Progress after the WOCE program

    Energy Technology Data Exchange (ETDEWEB)

    Gagnon, Alan R. E-mail: agagnon@whoi.edu; McNichol, Ann P.; Donoghue, Joanne C.; Stuart, Dana R.; Reden, Karl von

    2000-10-01

    Since 1991, the primary charge of the National Ocean Sciences AMS (NOSAMS) facility at the Woods Hole Oceanographic Institution has been to supply high throughput, high precision AMS {sup 14}C analyses for seawater samples collected as part of the World Ocean Circulation Experiment (WOCE). Approximately 13,000 samples taken as part of WOCE should be fully analyzed by the end of Y2K. Additional sample sources and techniques must be identified and incorporated if NOSAMS is to continue in its present operation mode. A trend in AMS today is the ability to routinely process and analyze radiocarbon samples that contain tiny amounts (<100 {mu}g) of carbon. The capability to mass-produce small samples for {sup 14}C analysis has been recognized as a major facility goal. The installation of a new 134-position MC-SNICS ion source, which utilizes a smaller graphite target cartridge than presently used, is one step towards realizing this goal. New preparation systems constructed in the sample preparation laboratory (SPL) include an automated bank of 10 small-volume graphite reactors, an automated system to process organic carbon samples, and a multi-dimensional preparative capillary gas chromatograph (PCGC)

  18. Sample preparation method for induced mutation on orchid

    International Nuclear Information System (INIS)

    Suhaimi Musa; Sakinah Ariffin

    2005-01-01

    Studies on the induction of mutation in Dendrobium orchid at MINT has produced a number of new orchid mutant cultivars. Tissue culture techniques on orchid seeds and meristem cloning are employed in preparing the samples for the mutation induction. Solid medium based on the Murashige and Skoog (1962) and liquid medium based on Vacin and Went (1949) were found to be suitable in producing protocorm like bodies (PLBs) that are required for the irradiation treatment. (Author)

  19. Generalized procedures for determining inspection sample sizes (related to quantitative measurements). Vol. 1: Detailed explanations

    International Nuclear Information System (INIS)

    Jaech, J.L.; Lemaire, R.J.

    1986-11-01

    Generalized procedures have been developed to determine sample sizes in connection with the planning of inspection activities. These procedures are based on different measurement methods. They are applied mainly to Bulk Handling Facilities and Physical Inventory Verifications. The present report attempts (i) to assign to appropriate statistical testers (viz. testers for gross, partial and small defects) the measurement methods to be used, and (ii) to associate the measurement uncertainties with the sample sizes required for verification. Working papers are also provided to assist in the application of the procedures. This volume contains the detailed explanations concerning the above mentioned procedures

  20. Cytotoxicity of Light-Cured Dental Materials according to Different Sample Preparation Methods

    Directory of Open Access Journals (Sweden)

    Myung-Jin Lee

    2017-03-01

    Full Text Available Dental light-cured resins can undergo different degrees of polymerization when applied in vivo. When polymerization is incomplete, toxic monomers may be released into the oral cavity. The present study assessed the cytotoxicity of different materials, using sample preparation methods that mirror clinical conditions. Composite and bonding resins were used and divided into four groups according to sample preparation method: uncured; directly cured samples, which were cured after being placed on solidified agar; post-cured samples were polymerized before being placed on agar; and “removed unreacted layer” samples had their oxygen-inhibition layer removed after polymerization. Cytotoxicity was evaluated using an agar diffusion test, MTT assay, and confocal microscopy. Uncured samples were the most cytotoxic, while removed unreacted layer samples were the least cytotoxic (p < 0.05. In the MTT assay, cell viability increased significantly in every group as the concentration of the extracts decreased (p < 0.05. Extracts from post-cured and removed unreacted layer samples of bonding resin were less toxic than post-cured and removed unreacted layer samples of composite resin. Removal of the oxygen-inhibition layer resulted in the lowest cytotoxicity. Clinicians should remove unreacted monomers on the resin surface immediately after restoring teeth with light-curing resin to improve the restoration biocompatibility.

  1. Coacervative extraction as a green technique for sample preparation for the analysis of organic compounds.

    Science.gov (United States)

    Melnyk, A; Wolska, L; Namieśnik, J

    2014-04-25

    One of the present trends in analytical chemistry is miniaturization, which is one of the methods of green analytical chemistry application. A particular emphasis is placed on the elimination of the use of large amounts of organic solvents which are toxic and harmful to the environment, maintaining high efficiency of the extraction process, high recovery values and low values of quantification (LOQ) and detection (LOD) limits. These requirements are fulfilled by coacervative extraction (CAE) technique. In this review, theoretical aspects of the coacervation process are presented along with environmental and bioanalytical applications of this technique, its advantages, limitations and competitiveness with other techniques. Due to its simplicity and rapidity, CAE is an excellent alternative for currently practiced procedures of sample preparation for the analysis of organic compounds. Copyright © 2014 Elsevier B.V. All rights reserved.

  2. Sample preparation prior to the LC-MS-based metabolomics/metabonomics of blood-derived samples.

    Science.gov (United States)

    Gika, Helen; Theodoridis, Georgios

    2011-07-01

    Blood represents a very important biological fluid and has been the target of continuous and extensive research for diagnostic, or health and drug monitoring reasons. Recently, metabonomics/metabolomics have emerged as a new and promising 'omics' platform that shows potential in biomarker discovery, especially in areas such as disease diagnosis, assessment of drug efficacy or toxicity. Blood is collected in various establishments in conditions that are not standardized. Next, the samples are prepared and analyzed using different methodologies or tools. When targeted analysis of key molecules (e.g., a drug or its metabolite[s]) is the aim, enforcement of certain measures or additional analyses may correct and harmonize these discrepancies. In omics fields such as those performed by holistic analytical approaches, no such rules or tools are available. As a result, comparison or correlation of results or data fusion becomes impractical. However, it becomes evident that such obstacles should be overcome in the near future to allow for large-scale studies that involve the assaying of samples from hundreds of individuals. In this case the effect of sample handling and preparation becomes very serious, in order to avoid wasting months of work from experts and expensive instrument time. The present review aims to cover the different methodologies applied to the pretreatment of blood prior to LC-MS metabolomic/metabonomic studies. The article tries to critically compare the methods and highlight issues that need to be addressed.

  3. Recent advances in sample preparation techniques and methods of sulfonamides detection - A review.

    Science.gov (United States)

    Dmitrienko, Stanislava G; Kochuk, Elena V; Apyari, Vladimir V; Tolmacheva, Veronika V; Zolotov, Yury A

    2014-11-19

    Sulfonamides (SAs) have been the most widely used antimicrobial drugs for more than 70 years, and their residues in foodstuffs and environmental samples pose serious health hazards. For this reason, sensitive and specific methods for the quantification of these compounds in numerous matrices have been developed. This review intends to provide an updated overview of the recent trends over the past five years in sample preparation techniques and methods for detecting SAs. Examples of the sample preparation techniques, including liquid-liquid and solid-phase extraction, dispersive liquid-liquid microextraction and QuEChERS, are given. Different methods of detecting the SAs present in food and feed and in environmental, pharmaceutical and biological samples are discussed. Copyright © 2014 Elsevier B.V. All rights reserved.

  4. Efficiency enhancement of perovskite solar cells by fabricating as-prepared film before sequential spin-coating procedure

    International Nuclear Information System (INIS)

    Jiang, Jiajia; Tao, Hai jun; Chen, Shanlong; Tan, Bin; Zhou, Ning; Zhu, Lumin; Zhao, Yuan; Wang, Yuqiao; Tao, Jie

    2016-01-01

    Graphical abstract: Schematic illustration of modified two-step spin-coating procedure for MAPbI 3 perovskite thin films. - Highlights: • An as-prepared CH 3 NH 3 PbI 3 and PbI 2 film was introduced before the traditional two-step process. • Smooth morphology and trace amount of remaining PbI 2 benefit the performance of solar cell. • The optimal as-prepared film introduced improves the efficiency of CH 3 NH 3 PbI 3 solar cells from 9.11% to 11.16%. - Abstract: Sequential spin-coating procedure is a widely adopted strategy to prepare CH 3 NH 3 PbI 3 on mesostructured TiO 2 electrode for organolead halide perovskite-based solar cells. However, this method suffers from the rough surface and excessively residual PbI 2 in the resulting perovskite film, deteriorating the device performance seriously. Herein, a facial modified sequential solution deposition method, by introducing an as-prepared CH 3 NH 3 PbI 3 and PbI 2 film before the traditional two-step process, was proposed to fabricate the perovskite-based solar cell with smooth morphology and trace amount of remaining PbI 2 . The optimal as-prepared film introduced improves the efficiency of CH 3 NH 3 PbI 3 solar cells from 9.11% to 11.16%. The enhancement of device performance can be attributed to the increased light absorption ability and decreased recombination rate of carriers in CH 3 NH 3 PbI 3 absorber.

  5. Monolith Chromatography as Sample Preparation Step in Virome Studies of Water Samples.

    Science.gov (United States)

    Gutiérrez-Aguirre, Ion; Kutnjak, Denis; Rački, Nejc; Rupar, Matevž; Ravnikar, Maja

    2018-01-01

    Viruses exist in aquatic media and many of them use this media as transmission route. Next-generation sequencing (NGS) technologies have opened new doors in virus research, allowing also to reveal a hidden diversity of viral species in aquatic environments. Not surprisingly, many of the newly discovered viruses are found in environmental fresh and marine waters. One of the problems in virome research can be the low amount of viral nucleic acids present in the sample in contrast to the background ones (host, eukaryotic, prokaryotic, environmental). Therefore, virus enrichment prior to NGS is necessary in many cases. In water samples, an added problem resides in the low concentration of viruses typically present in aquatic media. Different concentration strategies have been used to overcome such limitations. CIM monoliths are a new generation of chromatographic supports that due to their particular structural characteristics are very efficient in concentration and purification of viruses. In this chapter, we describe the use of CIM monolithic chromatography for sample preparation step in NGS studies targeting viruses in fresh or marine water. The step-by-step protocol will include a case study where CIM concentration was used to study the virome of a wastewater sample using NGS.

  6. Electrodeposition as a sample preparation technique for TXRF analysis

    International Nuclear Information System (INIS)

    Griesel, S.; Reus, U.; Prange, A.

    2000-01-01

    TXRF analysis of trace elements at concentrations in the μg/L range and below in high salt matrices normally requires a number of sample preparation steps that include separation of the salt matrix and preconcentration of the trace elements. A neat approach which allows samples to be prepared straightforwardly in a single step involves the application of electrochemical deposition using the TXRF sample support itself as an electrode. For this work a common three-electrode arrangement (radiometer analytical) with a rotating disc electrode as the working electrode, as is frequently employed in voltametric analysis, has been used. A special electrode tip has been constructed as a holder for the sample carrier which consists of polished glassy carbon. This material has been proven to be suitable for both its electrical and chemical properties. Measurements of the trace elements were performed using the ATOMIKA 8030C TXRF spectrometer, with the option of variable incident angles. In first experiments an artificial sea water matrix containing various trace elements in the μg/L range has been used. Elements such as Cr, Mn, Fe, Co, Ni, Cu, Zn, Ag, Cd, Hg, and Pb deposited on glassy carbon carriers. The deposition can be optimized by controlling the potential of the working electrode with respect to the reference electrode. Metal ions with a suitable standard potential are reduced to the metallic state and plated onto the electrode surface. When deposition is finished the sample carrier is demounted, rinsed with ultra-pure water and measured directly. Deposition yields for the elements under investigation are quite similar, and with an appropriate choice of the reference element, quantification can be achieved directly by internal standardization. The influence of parameters such as time, pH value, and trace element concentration on the deposition yield has been examined, and the results will be presented along with reproducibility studies. (author)

  7. Sample preparation for arsenic speciation analysis in baby food by generation of substituted arsines with atomic absorption spectrometry detection.

    Science.gov (United States)

    Huber, Charles S; Vale, Maria Goreti R; Dessuy, Morgana B; Svoboda, Milan; Musil, Stanislav; Dědina, Jiři

    2017-12-01

    A slurry sampling procedure for arsenic speciation analysis in baby food by arsane generation, cryogenic trapping and detection with atomic absorption spectrometry is presented. Several procedures were tested for slurry preparation, including different reagents (HNO 3 , HCl and tetramethylammonium hydroxide - TMAH) and their concentrations, water bath heating and ultrasound-assisted agitation. The best results for inorganic arsenic (iAs) and dimethylarsinate (DMA) were reached when using 3molL -1 HCl under heating and ultrasound-assisted agitation. The developed method was applied for the analysis of five porridge powder and six baby meal samples. The trueness of the method was checked with a certified reference material (CRM) of total arsenic (tAs), iAs and DMA in rice (ERM-BC211). Arsenic recoveries (mass balance) for all samples and CRM were performed by the determination of the tAs by inductively coupled plasma mass spectrometry (ICP-MS) after microwave-assisted digestion and its comparison against the sum of the results from the speciation analysis. The relative limits of detection were 0.44, 0.24 and 0.16µgkg -1 for iAs, methylarsonate and DMA, respectively. The concentrations of the most toxic arsenic species (iAs) in the analyzed baby food samples ranged between 4.2 and 99µgkg -1 which were below the limits of 300, 200 and 100µgkg -1 set by the Brazilian, Chinese and European legislation, respectively. Copyright © 2017 Elsevier B.V. All rights reserved.

  8. Guidance document for preparing water sampling and analysis plans for UMTRA Project sites. Revision 1

    International Nuclear Information System (INIS)

    1995-09-01

    A water sampling and analysis plan (WSAP) is prepared for each Uranium Mill Tailings Remedial Action (UMTRA) Project site to provide the rationale for routine ground water sampling at disposal sites and former processing sites. The WSAP identifies and justifies the sampling locations, analytical parameters, detection limits, and sampling frequency for the routine ground water monitoring stations at each site. This guidance document has been prepared by the Technical Assistance Contractor (TAC) for the US Department of Energy (DOE). Its purpose is to provide a consistent technical approach for sampling and monitoring activities performed under the WSAP and to provide a consistent format for the WSAP documents. It is designed for use by the TAC in preparing WSAPs and by the DOE, US Nuclear Regulatory Commission, state and tribal agencies, other regulatory agencies, and the public in evaluating the content of WSAPS

  9. Sample preparation for large-scale bioanalytical studies based on liquid chromatographic techniques.

    Science.gov (United States)

    Medvedovici, Andrei; Bacalum, Elena; David, Victor

    2018-01-01

    Quality of the analytical data obtained for large-scale and long term bioanalytical studies based on liquid chromatography depends on a number of experimental factors including the choice of sample preparation method. This review discusses this tedious part of bioanalytical studies, applied to large-scale samples and using liquid chromatography coupled with different detector types as core analytical technique. The main sample preparation methods included in this paper are protein precipitation, liquid-liquid extraction, solid-phase extraction, derivatization and their versions. They are discussed by analytical performances, fields of applications, advantages and disadvantages. The cited literature covers mainly the analytical achievements during the last decade, although several previous papers became more valuable in time and they are included in this review. Copyright © 2017 John Wiley & Sons, Ltd.

  10. Sample Preparation and Identification of Biological, Chemical and Mid-Spectrum Agents

    National Research Council Canada - National Science Library

    Hancock, J. R; Dragon, D. C

    2005-01-01

    A general survey of sample preparation and identification techniques for biological, chemical and mid-spectrum agents was conducted as part of Canada's contribution to a joint NATO Allied Engineering Publication (AEP) handbook...

  11. Continuous quality control of the blood sampling procedure using a structured observation scheme

    DEFF Research Database (Denmark)

    Seemann, T. L.; Nybo, M.

    2015-01-01

    Background: An important preanalytical factor is the blood sampling procedure and its adherence to the guidelines, i.e. CLSI and ISO 15189, in order to ensure a consistent quality of the blood collection. Therefore, it is critically important to introduce quality control on this part of the process....... As suggested by the EFLM working group on the preanalytical phase we introduced continuous quality control of the blood sampling procedure using a structured observation scheme to monitor the quality of blood sampling performed on an everyday basis. Materials and methods: Based on our own routines the EFLM....... Conclusion: It is possible to establish a continuous quality control on blood sampling. It has been well accepted by the staff and we have already been able to identify critical areas in the sampling process. We find that continuous auditing increase focus on the quality of blood collection which ensures...

  12. Polypyrrole solid phase microextraction: A new approach to rapid sample preparation for the monitoring of antibiotic drugs

    Energy Technology Data Exchange (ETDEWEB)

    Szultka, Malgorzata [Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus, Copernicus University, Gagarin 7, 87-100 Torun (Poland); Kegler, Ricarda [Institute of Clinical Pharmacology, University of Rostock, Schillingallee 70, D-18057 Rostock (Germany); Fuchs, Patricia [Department of Anaesthesia and Intensive Care, University of Rostock, Schillingallee 35, D-18057 Rostock (Germany); Olszowy, Pawel [Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus, Copernicus University, Gagarin 7, 87-100 Torun (Poland); Miekisch, Wolfram; Schubert, Jochen K. [Department of Anaesthesia and Intensive Care, University of Rostock, Schillingallee 35, D-18057 Rostock (Germany); Buszewski, Boguslaw [Department of Environmental Chemistry and Bioanalytics, Faculty of Chemistry, Nicolaus, Copernicus University, Gagarin 7, 87-100 Torun (Poland); Mundkowski, Ralf G., E-mail: ralf.mundkowski@med.uni-rostock.de [Institute of Clinical Pharmacology, University of Rostock, Schillingallee 70, D-18057 Rostock (Germany)

    2010-05-14

    Simple or even rapid bioanalytical methods are rare, since they generally involve complicated, time-consuming sample preparation from the biological matrices like LLE or SPE. SPME provides a promising approach to overcome these limitations. The full potential of this innovative technique for medical diagnostics, pharmacotherapy or biochemistry has not been tapped yet. In-house manufactured SPME probes with polypyrrole (PPy) coating were evaluated using three antibiotics of high clinical relevance - linezolid, daptomycin, and moxifloxacin - from PBS, plasma, and whole blood. The PPy coating was characterised by scanning electron microscopy. Influences of pH, inorganic salt, and blood anticoagulants were studied for optimum performance. Extraction yields were determined from stagnant media as well as re-circulating human blood using the heart-and-lung machine model system. The PPy-SPME fibres showed high extraction yields, particularly regarding linezolid. The reproducibility of the method was optimised to achieve RSDs of 9% or 17% and 7% for SPME from stagnant or re-circulating blood using fresh and re-used fibres, respectively. The PPy-SPME approach was demonstrated to meet the requirements of therapeutic monitoring of the drugs tested, even from re-circulating blood at physiological flow rates. SPME represents a rapid and simple dual-step procedure with potency to significantly reduce the effort and expenditure of complicated sample preparations in biomedical analysis.

  13. Polypyrrole solid phase microextraction: A new approach to rapid sample preparation for the monitoring of antibiotic drugs

    International Nuclear Information System (INIS)

    Szultka, Malgorzata; Kegler, Ricarda; Fuchs, Patricia; Olszowy, Pawel; Miekisch, Wolfram; Schubert, Jochen K.; Buszewski, Boguslaw; Mundkowski, Ralf G.

    2010-01-01

    Simple or even rapid bioanalytical methods are rare, since they generally involve complicated, time-consuming sample preparation from the biological matrices like LLE or SPE. SPME provides a promising approach to overcome these limitations. The full potential of this innovative technique for medical diagnostics, pharmacotherapy or biochemistry has not been tapped yet. In-house manufactured SPME probes with polypyrrole (PPy) coating were evaluated using three antibiotics of high clinical relevance - linezolid, daptomycin, and moxifloxacin - from PBS, plasma, and whole blood. The PPy coating was characterised by scanning electron microscopy. Influences of pH, inorganic salt, and blood anticoagulants were studied for optimum performance. Extraction yields were determined from stagnant media as well as re-circulating human blood using the heart-and-lung machine model system. The PPy-SPME fibres showed high extraction yields, particularly regarding linezolid. The reproducibility of the method was optimised to achieve RSDs of 9% or 17% and 7% for SPME from stagnant or re-circulating blood using fresh and re-used fibres, respectively. The PPy-SPME approach was demonstrated to meet the requirements of therapeutic monitoring of the drugs tested, even from re-circulating blood at physiological flow rates. SPME represents a rapid and simple dual-step procedure with potency to significantly reduce the effort and expenditure of complicated sample preparations in biomedical analysis.

  14. Preparation of 45Ca(HDEHP)n and (CaH1502)2 samples for liquid scintillation counting, compared to 45caCl2 results

    International Nuclear Information System (INIS)

    Rodriguez, L.; Arcos, J. M. los; Grau Malonda, A.

    1994-01-01

    A procedure for preparation of liquid scintillation counting organic samples of the Di-2-ethylhexyl phosphate calcium complex and the 2-ethylhexanoate calcium salt, labelled with 45Ca, is described. The chemical quench, the counting stability and spectral evolution of both compounds is studied in six scintillators,Toluene-alcohol, Dioxane-naphtalene, Hi safe II, Ultimate-Gold and Instagel, and compared to results obtained from a commercial solution of 4 5CaCl2. (Author) 7 refs

  15. Bone preparation at the KCCAMS laboratory

    Energy Technology Data Exchange (ETDEWEB)

    Beaumont, Will, E-mail: wbeaumon@uci.ed [Earth System Science Dept., University of California, B321 Croul Hall, Irvine, CA 92697-3100 (United States); Beverly, Robert; Southon, John [Earth System Science Dept., University of California, B321 Croul Hall, Irvine, CA 92697-3100 (United States); Taylor, R.E. [Department of Anthropology, University of California, Riverside, CA 92521 (United States)

    2010-04-15

    Collagen purification by ultrafiltration is becoming widely accepted as a superior {sup 14}C sample preparation method for removing environmental contamination from archaeological bone. We present an overview of bone sample preparation methods used at the KCCAMS laboratory, UC Irvine. Methods development data are also discussed, including results of tests of gelatinization temperature, evaluation of 10 kDa vs. 30 kDa molecular weight (MW) ultrafiltration, improvements to ultrafilter cleaning methods, tests of ultrafilter memory, and ultrafilter glycerin contamination. These tests were not intended to be exhaustive, but rather to show how standard procedures can be validated and improved with relatively little effort.

  16. Preparing and measuring ultra-small radiocarbon samples with the ARTEMIS AMS facility in Saclay, France

    Energy Technology Data Exchange (ETDEWEB)

    Delque-Kolic, E., E-mail: emmanuelle.delque-kolic@cea.fr [LMC14, CEA Saclay, Batiment 450 Porte 4E, 91191 Gif sur Yvette (France); Comby-Zerbino, C.; Ferkane, S.; Moreau, C.; Dumoulin, J.P.; Caffy, I.; Souprayen, C.; Quiles, A.; Bavay, D.; Hain, S.; Setti, V. [LMC14, CEA Saclay, Batiment 450 Porte 4E, 91191 Gif sur Yvette (France)

    2013-01-15

    The ARTEMIS facility in Saclay France measures, on average, 4500 samples a year for French organizations working in an array of fields, including environmental sciences, archeology and hydrology. In response to an increasing demand for the isolation of specific soil compounds and organic water fractions, we were motivated to evaluate our ability to reduce microgram samples using our standard graphitization lines and to measure the graphite thus obtained with our 3MV NEC Pelletron AMS. Our reduction facility consists of two fully automated graphitization lines. Each line has 12 reduction reactors with a reduction volume of 18 ml for the first line and 12 ml for the second. Under routine conditions, we determined that we could reduce the samples down to 10 {mu}g of carbon, even if the graphitization yield is consequently affected by the lower sample mass. Our results when testing different Fe/C ratios suggest that an amount of 1.5 mg of Fe powder was ideal (instead of lower amounts of catalyst) to prevent the sample from deteriorating too quickly under the Cs+ beam, and to facilitate pressing procedures. Several sets of microsamples produced from HOxI standard, international references and backgrounds were measured. When measuring {sup 14}C-free wood charcoal and HOxI samples we determined that our modern and dead blanks, due to the various preparation steps, were of 1.1 {+-} 0.8 and 0.2 {+-} 0.1 {mu}g, respectively. The results presented here were obtained for IAEA-C1, {sup 14}C-free wood, IAEA-C6, IAEA-C2 and FIRI C.

  17. Preparing and measuring ultra-small radiocarbon samples with the ARTEMIS AMS facility in Saclay, France

    International Nuclear Information System (INIS)

    Delqué-Količ, E.; Comby-Zerbino, C.; Ferkane, S.; Moreau, C.; Dumoulin, J.P.; Caffy, I.; Souprayen, C.; Quilès, A.; Bavay, D.; Hain, S.; Setti, V.

    2013-01-01

    The ARTEMIS facility in Saclay France measures, on average, 4500 samples a year for French organizations working in an array of fields, including environmental sciences, archeology and hydrology. In response to an increasing demand for the isolation of specific soil compounds and organic water fractions, we were motivated to evaluate our ability to reduce microgram samples using our standard graphitization lines and to measure the graphite thus obtained with our 3MV NEC Pelletron AMS. Our reduction facility consists of two fully automated graphitization lines. Each line has 12 reduction reactors with a reduction volume of 18 ml for the first line and 12 ml for the second. Under routine conditions, we determined that we could reduce the samples down to 10 μg of carbon, even if the graphitization yield is consequently affected by the lower sample mass. Our results when testing different Fe/C ratios suggest that an amount of 1.5 mg of Fe powder was ideal (instead of lower amounts of catalyst) to prevent the sample from deteriorating too quickly under the Cs+ beam, and to facilitate pressing procedures. Several sets of microsamples produced from HOxI standard, international references and backgrounds were measured. When measuring 14 C-free wood charcoal and HOxI samples we determined that our modern and dead blanks, due to the various preparation steps, were of 1.1 ± 0.8 and 0.2 ± 0.1 μg, respectively. The results presented here were obtained for IAEA-C1, 14 C-free wood, IAEA-C6, IAEA-C2 and FIRI C.

  18. Preparation of solid-state samples of a transition metal coordination compound for synchrotron radiation photoemission studies

    CERN Document Server

    Crotti, C; Celestino, T; Fontana, S

    2003-01-01

    The aim of this research was to identify a sample preparation method suitable for the study of transition metal complexes by photoemission spectroscopy with synchrotron radiation as the X-ray source, even in the case where the compound is not evaporable. Solid-phase samples of W(CO) sub 4 (dppe) [dppe=1,2-bis(diphenylphosphino)ethane] were prepared according to different methods and their synchrotron radiation XPS spectra measured. The spectra acquired from samples prepared by spin coating show core level peaks only slightly broader than the spectrum recorded from UHV evaporated samples. Moreover, for these samples the reproducibility of the binding energy values is excellent. The dependence of the spin coating technique on parameters such as solvent and solution concentration, spinning speed and support material was studied. The same preparation method also allowed the acquisition of valence band spectra, the main peaks of which were clearly resolved. The results suggest that use of the spin coating techniqu...

  19. Influence of Freezing and Storage Procedure on Human Urine Samples in NMR-Based Metabolomics

    Directory of Open Access Journals (Sweden)

    Burkhard Luy

    2013-04-01

    Full Text Available It is consensus in the metabolomics community that standardized protocols should be followed for sample handling, storage and analysis, as it is of utmost importance to maintain constant measurement conditions to identify subtle biological differences. The aim of this work, therefore, was to systematically investigate the influence of freezing procedures and storage temperatures and their effect on NMR spectra as a potentially disturbing aspect for NMR-based metabolomics studies. Urine samples were collected from two healthy volunteers, centrifuged and divided into aliquots. Urine aliquots were frozen either at −20 °C, on dry ice, at −80 °C or in liquid nitrogen and then stored at −20 °C, −80 °C or in liquid nitrogen vapor phase for 1–5 weeks before NMR analysis. Results show spectral changes depending on the freezing procedure, with samples frozen on dry ice showing the largest deviations. The effect was found to be based on pH differences, which were caused by variations in CO2 concentrations introduced by the freezing procedure. Thus, we recommend that urine samples should be frozen at −20 °C and transferred to lower storage temperatures within one week and that freezing procedures should be part of the publication protocol.

  20. Influence of Freezing and Storage Procedure on Human Urine Samples in NMR-Based Metabolomics.

    Science.gov (United States)

    Rist, Manuela J; Muhle-Goll, Claudia; Görling, Benjamin; Bub, Achim; Heissler, Stefan; Watzl, Bernhard; Luy, Burkhard

    2013-04-09

    It is consensus in the metabolomics community that standardized protocols should be followed for sample handling, storage and analysis, as it is of utmost importance to maintain constant measurement conditions to identify subtle biological differences. The aim of this work, therefore, was to systematically investigate the influence of freezing procedures and storage temperatures and their effect on NMR spectra as a potentially disturbing aspect for NMR-based metabolomics studies. Urine samples were collected from two healthy volunteers, centrifuged and divided into aliquots. Urine aliquots were frozen either at -20 °C, on dry ice, at -80 °C or in liquid nitrogen and then stored at -20 °C, -80 °C or in liquid nitrogen vapor phase for 1-5 weeks before NMR analysis. Results show spectral changes depending on the freezing procedure, with samples frozen on dry ice showing the largest deviations. The effect was found to be based on pH differences, which were caused by variations in CO2 concentrations introduced by the freezing procedure. Thus, we recommend that urine samples should be frozen at -20 °C and transferred to lower storage temperatures within one week and that freezing procedures should be part of the publication protocol.

  1. New procedure of selected biogenic amines determination in wine samples by HPLC

    Energy Technology Data Exchange (ETDEWEB)

    Piasta, Anna M.; Jastrzębska, Aneta, E-mail: aj@chem.uni.torun.pl; Krzemiński, Marek P.; Muzioł, Tadeusz M.; Szłyk, Edward

    2014-06-27

    Highlights: • We proposed new procedure for derivatization of biogenic amines. • The NMR and XRD analysis confirmed the purity and uniqueness of derivatives. • Concentration of biogenic amines in wine samples were analyzed by RP-HPLC. • Sample contamination and derivatization reactions interferences were minimized. - Abstract: A new procedure for determination of biogenic amines (BA): histamine, phenethylamine, tyramine and tryptamine, based on the derivatization reaction with 2-chloro-1,3-dinitro-5-(trifluoromethyl)-benzene (CNBF), is proposed. The amines derivatives with CNBF were isolated and characterized by X-ray crystallography and {sup 1}H, {sup 13}C, {sup 19}F NMR spectroscopy in solution. The novelty of the procedure is based on the pure and well-characterized products of the amines derivatization reaction. The method was applied for the simultaneous analysis of the above mentioned biogenic amines in wine samples by the reversed phase-high performance liquid chromatography. The procedure revealed correlation coefficients (R{sup 2}) between 0.9997 and 0.9999, and linear range: 0.10–9.00 mg L{sup −1} (histamine); 0.10–9.36 mg L{sup -1} (tyramine); 0.09–8.64 mg L{sup −1} (tryptamine) and 0.10–8.64 mg L{sup −1} (phenethylamine), whereas accuracy was 97%–102% (recovery test). Detection limit of biogenic amines in wine samples was 0.02–0.03 mg L{sup −1}, whereas quantification limit ranged 0.05–0.10 mg L{sup −1}. The variation coefficients for the analyzed amines ranged between 0.49% and 3.92%. Obtained BA derivatives enhanced separation the analytes on chromatograms due to the inhibition of hydrolysis reaction and the reduction of by-products formation.

  2. Microfluidic devices for sample preparation and rapid detection of foodborne pathogens

    DEFF Research Database (Denmark)

    Kant, Krishna; Shahbazi, Mohammad-Ali; Dave, Vivek Priy

    2018-01-01

    and improve the limit of detections. Integration of pathogen capturing bio-receptors on microfluidic devices is a crucial step, which can facilitate recognition abilities in harsh chemical and physical conditions, offering a great commercial benefit to the food-manufacturing sector. This article reviews...... diagnosis competences. This has prompted researchers to call the current status of detection approaches into question and leverage new technologies for superior pathogen sensing outcomes. Novel strategies mainly rely on incorporating all the steps from sample preparation to detection in miniaturized devices...... recent advances in current state-of-the-art of sample preparation and concentration from food matrices with focus on bacterial capturing methods and sensing technologies, along with their advantages and limitations when integrated into microfluidic devices for online rapid detection of pathogens in foods...

  3. Study of sample preparation in the measurement of 36Ar(n, p)36Cl reaction cross section

    International Nuclear Information System (INIS)

    Jiang Songsheng; Hemick, T.K.

    1992-01-01

    The preparation of enriched 36 Ar gas samples and 36 Cl samples for the use in the AMS measurement of 36 Ar(n, p) 36 Cl reaction cross section was described. The 36 Ar samples prepared had the volumes of about 0.4 ml and the weights of about 0.5 mg. The uncertainty in atomic numbers of 36 Ar was (0.3∼0.4)%. The reaction product, 36 Cl, in the 36 Ar was collected and the AgCl samples were prepared

  4. Dynamic Headspace Sampling as an Initial Step for Sample Preparation in Chromatographic Analysis.

    Science.gov (United States)

    Wojnowski, Wojciech; Majchrzak, Tomasz; Dymerski, Tomasz; Gębicki, Jacek; Namieśnik, Jacek

    2017-11-01

    This work represents a brief summary of the use of dynamic headspace (DHS) as a technique for sample preparation in chromatographic analysis. Despite numerous developments in the area of analyte isolation and enrichment, DHS remains one of the fundamental methods used with GC. In our opinion, interest in this technique will not diminish significantly because it conforms to stipulations of green analytical chemistry. Moreover, DHS fulfills the need for methods that facilitate detection and determination of analytes present at ultratrace levels in complex matrixes. The main focus of this work was placed on the theoretical fundamentals of this method. Also described herein were DHS development, the advantages and disadvantages of this technique compared with other headspace sampling techniques, and selected examples of its applications in food and environmental analyses.

  5. The working procedure of human autopsy specimens

    International Nuclear Information System (INIS)

    Chen Rusong; Liu Guodong

    2000-01-01

    In order to perform the Coordinated Research Program for the Reference Asian Man (phase 2): Ingestion and body content of trace elements of importance in Radiation Protection, study on elemental content in organs of normal Chinese has been worked by China Institute for Radiation Protection and Institute of Radiation Medicine - CAMS in recent two years. Sampling and sample collection of human tissues and the procedures of sample preparation of human autopsy specimens are enlisted

  6. Synthetic Multiple-Imputation Procedure for Multistage Complex Samples

    Directory of Open Access Journals (Sweden)

    Zhou Hanzhi

    2016-03-01

    Full Text Available Multiple imputation (MI is commonly used when item-level missing data are present. However, MI requires that survey design information be built into the imputation models. For multistage stratified clustered designs, this requires dummy variables to represent strata as well as primary sampling units (PSUs nested within each stratum in the imputation model. Such a modeling strategy is not only operationally burdensome but also inferentially inefficient when there are many strata in the sample design. Complexity only increases when sampling weights need to be modeled. This article develops a generalpurpose analytic strategy for population inference from complex sample designs with item-level missingness. In a simulation study, the proposed procedures demonstrate efficient estimation and good coverage properties. We also consider an application to accommodate missing body mass index (BMI data in the analysis of BMI percentiles using National Health and Nutrition Examination Survey (NHANES III data. We argue that the proposed methods offer an easy-to-implement solution to problems that are not well-handled by current MI techniques. Note that, while the proposed method borrows from the MI framework to develop its inferential methods, it is not designed as an alternative strategy to release multiply imputed datasets for complex sample design data, but rather as an analytic strategy in and of itself.

  7. Ultrasonic assisted extraction - an alternative for sample preparation (M4)

    International Nuclear Information System (INIS)

    Santos Junior, P.; Barbosa Junior, F.; Krug, F.J.; Trevizan, L.C.; Nobrega, J.A.

    2002-01-01

    Full text: In the last years the ultrasound assisted metal extraction has been frequency proposed as a simple and inexpensive alternative for sample preparation of biological and inorganic samples. The extraction effect is considered as being caused by acoustic cavitation, that is, bubble formation and subsequent disruptive action. The collapse of bubbles created by sonication of solutions results in the generation of extremely high local temperature and pressure gradients, which may be regarded as localized 'hot spots'. On a timescale of about 10 -10 s, effective local pressures and temperature of about 10 5 atm and about 5000 K, respectively, are generated under sonochemical conditions. Usually, this method uses a diluted acid medium decreasing blank values and reducing both reagents and time consumption compared to traditional wet digestion systems using conductive or microwave-assisted heating. Furthermore, sonication can also allow the preparation of samples directly within the sample container, thereby preventing sample losses and minimizing sample contamination. Although some controversial results concerning metals extraction behavior have been reported, they could be explained by analyte-matrix interaction and the ability of the ultrasonic processor to generate ultrasound (i.e. the use of an ultrasonic bath or an ultrasonic probe at different power, frequency, and amplitude). This contribution presents a review of ultrasound assisted metal extraction and recent performance data obtained in our laboratory for determination of elements in biological materials, soils and sediments by ICP-OES and ETAAS. The effect of extraction parameters, such as type and concentration of the leaching solution, sonication time and performance of ultrasonic processor (bath or probe) will be presented. (author)

  8. Homogeneous immunosubtraction integrated with sample preparation is enabled by a microfluidic format

    Science.gov (United States)

    Apori, Akwasi A.; Herr, Amy E.

    2011-01-01

    Immunosubtraction is a powerful and resource-intensive laboratory medicine assay that reports both protein mobility and binding specificity. To expedite and automate this electrophoretic assay, we report on advances to the electrophoretic immunosubtraction assay by introducing a homogeneous, not heterogeneous, format with integrated sample preparation. To accomplish homogeneous immunosubtraction, a step-decrease in separation matrix pore-size at the head of a polyacrylamide gel electrophoresis (PAGE) separation channel enables ‘subtraction’ of target analyte when capture antibody is present (as the large immune-complex is excluded from PAGE), but no subtraction when capture antibody is absent. Inclusion of sample preparation functionality via small pore size polyacrylamide membranes is also key to automated operation (i.e., sample enrichment, fluorescence sample labeling, and mixing of sample with free capture antibody). Homogenous sample preparation and assay operation allows on-the-fly, integrated subtraction of one to multiple protein targets and reuse of each device. Optimization of the assay is detailed which allowed for ~95% subtraction of target with 20% non-specific extraction of large species at the optimal antibody-antigen ratio, providing conditions needed for selective target identification. We demonstrate the assay on putative markers of injury and inflammation in cerebrospinal fluid (CSF), an emerging area of diagnostics research, by rapidly reporting protein mobility and binding specificity within the sample matrix. We simultaneously detect S100B and C-reactive protein, suspected biomarkers for traumatic brain injury (TBI), in ~2 min. Lastly, we demonstrate S100B detection (65 nM) in raw human CSF with a lower limit of detection of ~3.25 nM, within the clinically relevant concentration range for detecting TBI in CSF. Beyond the novel CSF assay introduced here, a fully automated immunosubtraction assay would impact a spectrum of routine but labor

  9. Recent Trends in Microextraction Techniques Employed in Analytical and Bioanalytical Sample Preparation

    Directory of Open Access Journals (Sweden)

    Abuzar Kabir

    2017-12-01

    Full Text Available Sample preparation has been recognized as a major step in the chemical analysis workflow. As such, substantial efforts have been made in recent years to simplify the overall sample preparation process. Major focusses of these efforts have included miniaturization of the extraction device; minimizing/eliminating toxic and hazardous organic solvent consumption; eliminating sample pre-treatment and post-treatment steps; reducing the sample volume requirement; reducing extraction equilibrium time, maximizing extraction efficiency etc. All these improved attributes are congruent with the Green Analytical Chemistry (GAC principles. Classical sample preparation techniques such as solid phase extraction (SPE and liquid-liquid extraction (LLE are being rapidly replaced with emerging miniaturized and environmentally friendly techniques such as Solid Phase Micro Extraction (SPME, Stir bar Sorptive Extraction (SBSE, Micro Extraction by Packed Sorbent (MEPS, Fabric Phase Sorptive Extraction (FPSE, and Dispersive Liquid-Liquid Micro Extraction (DLLME. In addition to the development of many new generic extraction sorbents in recent years, a large number of molecularly imprinted polymers (MIPs created using different template molecules have also enriched the large cache of microextraction sorbents. Application of nanoparticles as high-performance extraction sorbents has undoubtedly elevated the extraction efficiency and method sensitivity of modern chromatographic analyses to a new level. Combining magnetic nanoparticles with many microextraction sorbents has opened up new possibilities to extract target analytes from sample matrices containing high volumes of matrix interferents. The aim of the current review is to critically audit the progress of microextraction techniques in recent years, which has indisputably transformed the analytical chemistry practices, from biological and therapeutic drug monitoring to the environmental field; from foods to phyto

  10. Crystal growth of YFe{sub 2}Ge{sub 2} and the dependence of its superconducting properties on sample preparation

    Energy Technology Data Exchange (ETDEWEB)

    Chen, Jiasheng; Semeniuk, Konstantin; Reiss, Pascal; Brown, Philip; Grosche, Malte [Cavendish Lab., Cambridge (United Kingdom); Feng, Zhuo [London Centre of Nanotechnology, UCL, London (United Kingdom); Lampronti, Giulio [Cambridge Univ., Dept. of Earth Sciences, Cambridge (United Kingdom)

    2016-07-01

    The d-electron system YFe{sub 2}Ge{sub 2} exhibits an unusually high Sommerfeld ratio of specific heat capacity of C/T ∝ 100 mJ/(molK{sup 2}), signaling strong electronic correlations. Evidence of superconductivity has been reported in polycrystals and in flux-grown single crystals with residual resistance ratios (RRR) of the order of 50, but these samples show no thermodynamic signatures of a bulk superconducting transition. We find that by combining (i) a prereaction of YFe{sub 2}, (ii) careful control of nominal composition, and (iii) subsequent annealing procedures, the polycrystalline YFe{sub 2}Ge{sub 2} samples grown using a radio-frequency (RF) induction furnace can reach RRR values ∝ 200 with resistive superconducting transitions temperatures of around 1.85 K. This new generation of sample displays clear heat capacity anomalies as well as nearly 100% diamagnetic screening, confirming the bulk nature of its superconductivity. We present details of the sample preparation and characterization and discuss the correlation between nominal composition and superconductivity.

  11. Effect of sample preparation methods on photometric determination of the tellurium and cobalt content in the samples of copper concentrates

    Directory of Open Access Journals (Sweden)

    Viktoriya Butenko

    2016-03-01

    Full Text Available Methods of determination of cobalt and nickel in copper concentrates currently used in factory laboratories are very labor intensive and time consuming. The limiting stage of the analysis is preliminary chemical sample preparation. Carrying out the decomposition process of industrial samples with concentrated mineral acids in open systems does not allow to improve the metrological characteristics of the methods, for this reason improvement the methods of sample preparation is quite relevant and has a practical interest. The work was dedicated to the determination of the optimal conditions of preliminary chemical preparation of copper concentrate samples for the subsequent determination of cobalt and tellurium in the obtained solution using tellurium-spectrophotometric method. Decomposition of the samples was carried out by acid dissolving in individual mineral acids and their mixtures by heating in an open system as well as by using ultrasonification and microwave radiation in a closed system. In order to select the optimal conditions for the decomposition of the samples in a closed system the phase contact time and ultrasonic generator’s power were varied. Intensification of the processes of decomposition of copper concentrates with nitric acid (1:1, ultrasound and microwave radiation allowed to transfer quantitatively cobalt and tellurium into solution spending 20 and 30 min respectively. This reduced the amount of reactants used and improved the accuracy of determination by running the process in strictly identical conditions.

  12. Sample preparation composite and replicate strategy case studies for assay of solid oral drug products.

    Science.gov (United States)

    Nickerson, Beverly; Harrington, Brent; Li, Fasheng; Guo, Michele Xuemei

    2017-11-30

    Drug product assay is one of several tests required for new drug products to ensure the quality of the product at release and throughout the life cycle of the product. Drug product assay testing is typically performed by preparing a composite sample of multiple dosage units to obtain an assay value representative of the batch. In some cases replicate composite samples may be prepared and the reportable assay value is the average value of all the replicates. In previously published work by Harrington et al. (2014) [5], a sample preparation composite and replicate strategy for assay was developed to provide a systematic approach which accounts for variability due to the analytical method and dosage form with a standard error of the potency assay criteria based on compendia and regulatory requirements. In this work, this sample preparation composite and replicate strategy for assay is applied to several case studies to demonstrate the utility of this approach and its application at various stages of pharmaceutical drug product development. Copyright © 2017 Elsevier B.V. All rights reserved.

  13. Integrated Automation of High-Throughput Screening and Reverse Phase Protein Array Sample Preparation

    DEFF Research Database (Denmark)

    Pedersen, Marlene Lemvig; Block, Ines; List, Markus

    into automated robotic high-throughput screens, which allows subsequent protein quantification. In this integrated solution, samples are directly forwarded to automated cell lysate preparation and preparation of dilution series, including reformatting to a protein spotter-compatible format after the high......-throughput screening. Tracking of huge sample numbers and data analysis from a high-content screen to RPPAs is accomplished via MIRACLE, a custom made software suite developed by us. To this end, we demonstrate that the RPPAs generated in this manner deliver reliable protein readouts and that GAPDH and TFR levels can...

  14. Sample collection and preparation of biofluids and extracts for gas chromatography-mass spectrometry.

    Science.gov (United States)

    Emwas, Abdul-Hamid M; Al-Talla, Zeyad A; Kharbatia, Najeh M

    2015-01-01

    To maximize the utility of gas chromatography-mass spectrometry (GC-MS) in metabonomics research, all stages of the experimental design should be standardized, including sample collection, storage, preparation, and sample separation. Moreover, the prerequisite for any GC-MS analysis is that a compound must be volatile and thermally stable if it is to be analyzed using this technique. Since many metabolites are nonvolatile and polar in nature, they are not readily amenable to analysis by GC-MS and require initial chemical derivatization of the polar functional groups in order to reduce the polarity and to increase the thermal stability and volatility of the analytes. In this chapter, an overview is presented of the optimum approach to sample collection, storage, and preparation for gas chromatography-mass spectrometry-based metabonomics with particular focus on urine samples as example of biofluids.

  15. The impact of changing antiseptic skin preparation agent used for cardiac implantable electronic device (CIED) procedures on the risk of infection.

    Science.gov (United States)

    Qintar, Mohammed; Zardkoohi, Omeed; Hammadah, Muhammad; Hsu, Amy; Wazni, Oussama; Wilkoff, Bruce L; Tarakji, Khaldoun G

    2015-02-01

    Cardiac implantable electronic device (CIED) infection is a major complication that is associated with increased morbidity and mortality. Recent data suggested a relationship between the antiseptic agent used for skin preparation at time of CIED procedure and risk for infection. On April 30, 2011, we changed the antiseptic agent used for skin preparation at our tertiary care facility from chlorhexidine-alcohol to povidone-iodine for all CIED procedures. We retrospectively reviewed records of all patients who underwent CIED procedure 1 year before and after the change. CIED infection was defined as pocket or endovascular systemic infection that required removal within 1 year of the index procedure. We examined if the change affected the risk of CIED infection. A total of 2,792 patients underwent 2,840 CIED procedures; 1,748 (61.5%) had implantable cardioverter defibrillator procedures and 1,092 (38.4%) had permanent pacemaker procedures. Chlorhexidine-alcohol agent was used in 1,450 (51.1%) procedures, and povidone-iodine agent was used in 1,390 (48.9%). After 1 year of follow-up, 31 patients (1.09%) developed CIED infection that required system removal. The 1-year infection rate was 1.1% among both antiseptic agent groups and there were no significant differences in the infection presentations among both groups (P = 0.950). Multivariate Cox proportional hazards regression model showed that risk factors for infection within 1 year included age, diabetes, and African American race. In one large cohort of patients undergoing CIED procedures, the antiseptic agent used for skin preparation (chlorhexidine-alcohol vs povidone-iodine) was not associated with increased risk of developing CIED infection. ©2014 Wiley Periodicals, Inc.

  16. Sample preparation strategies for food and biological samples prior to nanoparticle detection and imaging

    DEFF Research Database (Denmark)

    Larsen, Erik Huusfeldt; Löschner, Katrin

    2014-01-01

    microscopy (TEM) proved to be necessary for trouble shooting of results obtained from AFFF-LS-ICP-MS. Aqueous and enzymatic extraction strategies were tested for thorough sample preparation aiming at degrading the sample matrix and to liberate the AgNPs from chicken meat into liquid suspension. The resulting...... AFFF-ICP-MS fractograms, which corresponded to the enzymatic digests, showed a major nano-peak (about 80 % recovery of AgNPs spiked to the meat) plus new smaller peaks that eluted close to the void volume of the fractograms. Small, but significant shifts in retention time of AFFF peaks were observed...... for the meat sample extracts and the corresponding neat AgNP suspension, and rendered sizing by way of calibration with AgNPs as sizing standards inaccurate. In order to gain further insight into the sizes of the separated AgNPs, or their possible dissolved state, fractions of the AFFF eluate were collected...

  17. Effect of method of sample preparation on ruminal in situ ...

    African Journals Online (AJOL)

    Midmar) was harvested at three and four weeks after cutting and fertilizing with 200 kg nitrogen (N)/ha. Freshly cut herbage was used to investigate the following four sample preparation methods. In trial 1, herbage was (1) chopped with a paper-cutting guillotine into 5-10 mm lengths, representing fresh (FR) herbage; ...

  18. Sampling method of environmental radioactivity monitoring

    International Nuclear Information System (INIS)

    1984-01-01

    This manual provides sampling methods of environmental samples of airborne dust, precipitated dust, precipitated water (rain or snow), fresh water, soil, river sediment or lake sediment, discharged water from a nuclear facility, grains, tea, milk, pasture grass, limnetic organisms, daily diet, index organisms, sea water, marine sediment, marine organisms, and that for tritium and radioiodine determination for radiation monitoring from radioactive fallout or radioactivity release by nuclear facilities. This manual aims at the presentation of standard sampling procedures for environmental radioactivity monitoring regardless of monitoring objectives, and shows preservation method of environmental samples acquired at the samplingpoint for radiation counting for those except human body. Sampling techniques adopted in this manual is decided by the criteria that they are suitable for routine monitoring and any special skillfulness is not necessary. Based on the above-mentioned principle, this manual presents outline and aims of sampling, sampling position or object, sampling quantity, apparatus, equipment or vessel for sampling, sampling location, sampling procedures, pretreatment and preparation procedures of a sample for radiation counting, necessary recording items for sampling and sample transportation procedures. Special attention is described in the chapter of tritium and radioiodine because these radionuclides might be lost by the above-mentioned sample preservation method for radiation counting of less volatile radionuclides than tritium or radioiodine. (Takagi, S.)

  19. Soybean and lactose in meat products and preparations sampled at retail

    Directory of Open Access Journals (Sweden)

    Filomena Piccolo

    2016-06-01

    Full Text Available Food allergies and intolerances have increased during the last decades and regulatory authorities have taken different measures to prevent and manage consumers’ adverse reactions, including correct labelling of foods. Aim of this work was to search for soybean and lactose in meat products and meat preparations taken from retail in some provinces of Campania Region (Southern Italy and to evaluate the food labels compliance with Regulation (EU n.1169/2011. Soybean and lactose were searched using commercial kits in n. 58 samples of meat products produced in or distributed by 19 establishments, and in n. 55 samples of meat products and n. 8 of meat preparations produced in 21 plants. All samples were selected on the basis of the absence of any information on the labels about the presence of the two searched allergens, with the exception of n. 5 samples tested for lactose. Traces of soybean were detected in 50 out of the 58 examined samples, at concentrations up to 0.93 mg kg–1. Only two samples contained levels above the detection limit of 0.31 mg kg–1. Lactose levels ranging from 0.11 to 2.95 g/100 g, i.e. above the detection limit, were found in all the tested samples (n. 63. The results of the present research underline the need for careful controls and planning by operators as part of the self-control plans, and deserve attention from the competent authorities considering not only the consumers’ health but also the great attention media pay to regulations providing consumers with information on food.

  20. Influence of sample preparation on the microstructure of tooth enamel apatite

    Czech Academy of Sciences Publication Activity Database

    Kallistová, Anna; Skála, Roman; Horáček, I.; Miyajima, N.; Malíková, R.

    2015-01-01

    Roč. 48, č. 3 (2015), s. 763-768 ISSN 0021-8898 Institutional support: RVO:67985831 Keywords : X-ray powder diffraction * sample preparation * microstructure * dental hydroxyapatite Subject RIV: BM - Solid Matter Physics ; Magnetism Impact factor: 3.720, year: 2014

  1. Therapeutic Use of Δ9-THC and Cannabidiol: Evaluation of a New Extraction Procedure for the Preparation of Cannabis-based Olive Oil.

    Science.gov (United States)

    Morini, Luca; Porro, Giorgio; Liso, Maurizio; Groppi, Angelo

    2017-01-01

    Since 2013 Cannabis-based preparations, containing the two main cannabinoids of interest, Δ9-tetrahydrocannabinol (THC), and cannabidiol (CBD), can be used for therapeutic purposes, such as palliative care, neurodegenerative disorder treatment and other therapies. The preparations may consist of a drug partition in sachets, capsules or through the extraction in certified olive oil. The aims of the study were: a) to develop and validate a new liquid chromatographictandem mass spectrometric (LC-MS/MS) method for the identification and quantification of THC and CBD in olive oil; b) to evaluate the extraction efficiency and reproducibility of a new commercial extractor on the market. The olive oil was simply diluted three consecutive times, using organic solvents with increasing polarity index (n-hexane → isopropanol → methanol). The sample was then directly injected into LC-MS/MS system, operating in Multiple Reaction Monitoring Mode, in positive polarization. The method was then fully validated. The method assessed to be linear over the range 0.1-10 ng/µL for both THC and CBD. Imprecision and accuracy were within 12.2% and 16.9% respectively; matrix effects proved to be negligible; THC concentration in oil is stable up to two months at room temperature, whenever kept in the dark. CBD provided a degradation of 30% within ten weeks. The method was then applied to olive oil after sample preparation, in order to evaluate the efficiency of extraction of a new generation instrument. Temperature of extraction is the most relevant factor to be optimized. Indeed, a difference of 2°C (from 94.5°C to 96.5°C, the highest temperature reached in the experiments) of the heating phase, increases the percentage of extraction from 54.2% to 64.0% for THC and from 58.2% to 67.0% for CBD. The amount of THC acid and CBD acid that are decarboxylated during the procedure must be check out in the future. The developed method was simple and fast. The extraction procedure proved to be

  2. Consensus guidelines for the use of bowel preparation prior to colonic diagnostic procedures: colonoscopy and small bowel video capsule endoscopy

    NARCIS (Netherlands)

    Mathus-Vliegen, Elisabeth; Pellisé, Maria; Heresbach, Denis; Fischbach, Wolfgang; Dixon, Tricia; Belsey, Jonathan; Parente, Fabrizio; Rio-Tinto, Ricardo; Brown, Alistair; Toth, Ervin; Crosta, Cristiano; Layer, Peter; Epstein, Owen; Boustiere, Christian

    2013-01-01

    Adequate bowel preparation prior to colonic diagnostic procedures is essential to ensure adequate visualisation. This consensus aims to provide guidance as to the appropriate use of bowel preparation for a range of defined clinical circumstances. A consensus group from across Europe was convened and

  3. An electrodeposition method for the preparation of actinides and Ra samples for α spectrometry

    International Nuclear Information System (INIS)

    Garcia-Tenorio, R.; Garcia-Leon, M.; Madurga, G.; Piazza, C.

    1986-01-01

    As it is confirmed in this work, electrodeposition of α radionuclides gives a simple method for preparing α samples of high spectrometric quality, compared to those prepared by evaporation. Then we give the methods for electrodepositon or α emitters use in our Department. Actinides α emitters are electroplated from a 1% H 2 SO 4 medium with a recovery of about 90%. The samples of Ra are prepared by electrodeposition from a HCl + CH 3 -COONH 4 medium at pH approx.= 5. In this case the recovery reaches a value that ranges from 70 to 90%. For these measurements a Si surface barrier detector has been used. Some of its features are discussed in the text. (author)

  4. On the preparation of as-produced and purified single-walled carbon nanotube samples for standardized X-ray diffraction characterization

    International Nuclear Information System (INIS)

    Allaf, Rula M.; Rivero, Iris V.; Spearman, Shayla S.; Hope-Weeks, Louisa J.

    2011-01-01

    The aim of this research was to specify proper sample conditioning for acquiring representative X-ray diffraction (XRD) profiles for single-walled carbon nanotube (SWCNT) samples. In doing so, a specimen preparation method for quantitative XRD characterization of as-produced and purified arc-discharge SWCNT samples has been identified. Series of powder XRD profiles were collected at different temperatures, states, and points of time to establish appropriate conditions for acquiring XRD profiles without inducing much change to the specimen. It was concluded that heating in the 300-450 deg. C range for 20 minutes, preferably vacuum-assisted, and then sealing the sample is an appropriate XRD specimen preparation technique for purified arc-discharge SWCNT samples, while raw samples do not require preconditioning for characterization. - Graphical Abstract: A sample preparation method for XRD characterization of as-produced and purified arc-discharge SWCNT samples is identified. The preparation technique seeks to acquire representative XRD profiles without inducing changes to the samples. Purified samples required 20 minutes of heating at (300-450)deg. C, while raw samples did not require preconditioning for characterization. Highlights: → Purification routines may induce adsorption onto the SWCNT samples. → Heating a SWCNT sample may result in material loss, desorption, and SWCNTs closing. → Raw arc-discharge samples do not require preparation for XRD characterization. → Heating is appropriate specimen preparation for purified and heat-treated samples. → XRD data fitting is required for structural analysis of SWCNT bundles.

  5. Sample preparation of Medicago sativa L. hay for chemical analysis ...

    African Journals Online (AJOL)

    The objective of this study was to quantify the effect of the grinding procedure on the moisture and crude protein concentration of a ground Medicago sativa L. hay sample for quality grading. An additional aim was to investigate the accuracy of electronic moisture testers (EMT). Variance of analyses revealed significant ...

  6. Preparation and calibration by liquid scintillation of a sample of Cl 36. Preparacion y calibracion por centelleo liquido de una muestra de Cl 36

    Energy Technology Data Exchange (ETDEWEB)

    Grau Malonda, A; Los Arcos, J M; Rodriguez Barquero, L; Suarez, C [Centro de Investigaciones Energeticas, Medioambientales y Tecnologicas, Madrid (Spain)

    1989-01-01

    A procedure to prepare a sample of Clorine 36, as Li{sup 36}Cl, able to be measured by liquid scintillation counting, is described. The sample is chemically stable, with no variation of the quenching parameter up to 4 mg of LiCl per 15 ml of scintillator, keeps constant the counting efficiency for concentration higher than 40 {mu}g of Li{sup 36}Cl in that volume, and shows no deterioration over a 3 weed period. The Li{sup 36}Cl solution has been standarized using the free parameter method with different volumes of toluene, PCS and Instagel, to an uncertainty of 0,3% (Author).

  7. Validation of a fully automated robotic setup for preparation of whole blood samples for LC-MS toxicology analysis

    DEFF Research Database (Denmark)

    Andersen, David Wederkinck; Rasmussen, Brian; Linnet, Kristian

    2012-01-01

    A fully automated setup was developed for preparing whole blood samples using a Tecan Evo workstation. By integrating several add-ons to the robotic platform, the flexible setup was able to prepare samples from sample tubes to a 96-well sample plate ready for injection on liquid chromatography...

  8. Efficiency enhancement of perovskite solar cells by fabricating as-prepared film before sequential spin-coating procedure

    Energy Technology Data Exchange (ETDEWEB)

    Jiang, Jiajia [Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, College of material science and technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211100 (China); Tao, Hai jun, E-mail: taohaijun@nuaa.edu.cn [Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, College of material science and technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211100 (China); Jiangsu Collaborative Innovation Center of Photovolatic Science and Engineering, Changzhou University, Changzhou 213164, Jiangsu (China); Chen, Shanlong; Tan, Bin [Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, College of material science and technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211100 (China); Zhou, Ning [Shanghai Electrochemical Energy Devices Research Center, School of Chemistry and Chemical Engineering, Shanghai Jiao Tong University, Shanghai 200240 (China); Zhu, Lumin; Zhao, Yuan [Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, College of material science and technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211100 (China); Wang, Yuqiao [Jiangsu Optoelectronic Functional Materials and Engineering Laboratory, School of Chemistry and Chemical Engineering, Southeast University, Nanjing 211189 (China); Tao, Jie [Jiangsu Key Laboratory of Materials and Technology for Energy Conversion, College of material science and technology, Nanjing University of Aeronautics and Astronautics, Nanjing 211100 (China)

    2016-05-15

    Graphical abstract: Schematic illustration of modified two-step spin-coating procedure for MAPbI{sub 3} perovskite thin films. - Highlights: • An as-prepared CH{sub 3}NH{sub 3}PbI{sub 3} and PbI{sub 2} film was introduced before the traditional two-step process. • Smooth morphology and trace amount of remaining PbI{sub 2} benefit the performance of solar cell. • The optimal as-prepared film introduced improves the efficiency of CH{sub 3}NH{sub 3}PbI{sub 3} solar cells from 9.11% to 11.16%. - Abstract: Sequential spin-coating procedure is a widely adopted strategy to prepare CH{sub 3}NH{sub 3}PbI{sub 3} on mesostructured TiO{sub 2} electrode for organolead halide perovskite-based solar cells. However, this method suffers from the rough surface and excessively residual PbI{sub 2} in the resulting perovskite film, deteriorating the device performance seriously. Herein, a facial modified sequential solution deposition method, by introducing an as-prepared CH{sub 3}NH{sub 3}PbI{sub 3} and PbI{sub 2} film before the traditional two-step process, was proposed to fabricate the perovskite-based solar cell with smooth morphology and trace amount of remaining PbI{sub 2}. The optimal as-prepared film introduced improves the efficiency of CH{sub 3}NH{sub 3}PbI{sub 3} solar cells from 9.11% to 11.16%. The enhancement of device performance can be attributed to the increased light absorption ability and decreased recombination rate of carriers in CH{sub 3}NH{sub 3}PbI{sub 3} absorber.

  9. A sample preparation method for recovering suppressed analyte ions in MALDI TOF MS

    NARCIS (Netherlands)

    Lou, X.; Waal, de B.F.M.; Milroy, L.G.; Dongen, van J.L.J.

    2015-01-01

    In matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF MS), analyte signals can be substantially suppressed by other compounds in the sample. In this technical note, we describe a modified thin-layer sample preparation method that significantly reduces the analyte

  10. Implementation of antimicrobial peptides for sample preparation prior to nucleic acid amplification in point-of-care settings.

    Science.gov (United States)

    Krõlov, Katrin; Uusna, Julia; Grellier, Tiia; Andresen, Liis; Jevtuševskaja, Jekaterina; Tulp, Indrek; Langel, Ülo

    2017-12-01

    A variety of sample preparation techniques are used prior to nucleic acid amplification. However, their efficiency is not always sufficient and nucleic acid purification remains the preferred method for template preparation. Purification is difficult and costly to apply in point-of-care (POC) settings and there is a strong need for more robust, rapid, and efficient biological sample preparation techniques in molecular diagnostics. Here, the authors applied antimicrobial peptides (AMPs) for urine sample preparation prior to isothermal loop-mediated amplification (LAMP). AMPs bind to many microorganisms such as bacteria, fungi, protozoa and viruses causing disruption of their membrane integrity and facilitate nucleic acid release. The authors show that incubation of E. coli with antimicrobial peptide cecropin P1 for 5 min had a significant effect on the availability of template DNA compared with untreated or even heat treated samples resulting in up to six times increase of the amplification efficiency. These results show that AMPs treatment is a very efficient sample preparation technique that is suitable for application prior to nucleic acid amplification directly within biological samples. Furthermore, the entire process of AMPs treatment was performed at room temperature for 5 min thereby making it a good candidate for use in POC applications.

  11. Guideline for Sampling and Analysis of Tar and Particles in Biomass Producer Gases. Version 3.3

    Energy Technology Data Exchange (ETDEWEB)

    Neeft, J.P.A.; Knoef, H.A.M.; Zielke, U.; Sjoestroem, K.; Hasler, P.; Simell, P.A.; Dorrington, M.A.; Thomas, L.; Abatzoglou, N.; Deutch, S.; Greil, C.; Buffinga, G.J.; Brage, C.; Suomalainen, M.

    2002-07-01

    This Guideline provides a set of procedures for the measurement of organic contaminants and particles in producer gases from biomass gasifiers. The procedures are designed to cover different gasifier types (updraft or downdraft fixed bed or fluidised bed gasifiers), operating conditions (0 - 900C and 0.6-60 bars) and concentration ranges (1 mg/m{sub n}{sup 3} to 300 g/m{sub n}{sup 3}). The Guideline describes a modular sampling train, and a set of procedures, which include: planning and preparation of the sampling, sampling and post-sampling, analysis, calculations, error analysis and reporting. The modular sampling train consists of 4 modules. Module 1 is a preconditioning module for isokinetic sampling and gas cooling. Module 2 is a particle collection module including a heated filter. Module 3 is a tar collection module with a gas quench (optionally by circulating a liquid), impinger bottles and a backup adsorber. Module 4 is a volume-sampling module consisting of a pump, a rotameter, a gas flow meter and pressure and temperature indicators. The equipment and materials that are required for procuring this modular sampling train are given in the Guideline. The sampling procedures consist of a description for isokinetic sampling, a leakage test prior to sampling, the actual sampling and its duration, how the equipment is cleaned after the sampling, and how the samples are prepared and stored. Analysis of the samples is performed via three procedures. Prior to these procedures, the sample is prepared by Soxhlet extraction of the tars on the particle filter and by collection of all tars in one bulk solution. The first procedure describes the weighing of the particle filter to obtain the concentration of particles in the biomass producer gas. The bulk tar solution is used for two purposes: for determination of gravimetric tar and for analysis of individual compounds. The second procedure describes how to determine the gravimetric tar mass from the bulk solution. The

  12. The Alaska Commercial Fisheries Water Quality Sampling Methods and Procedures Manual

    Energy Technology Data Exchange (ETDEWEB)

    Folley, G.; Pearson, L.; Crosby, C. [Alaska Dept. of Environmental Conservation, Soldotna, AK (United States); DeCola, E.; Robertson, T. [Nuka Research and Planning Group, Seldovia, AK (United States)

    2006-07-01

    A comprehensive water quality sampling program was conducted in response to the oil spill that occurred when the M/V Selendang Ayu ship ran aground near a major fishing port at Unalaska Island, Alaska in December 2004. In particular, the sampling program focused on the threat of spilled oil to the local commercial fisheries resources. Spill scientists were unable to confidently model the movement of oil away from the wreck because of limited oceanographic data. In order to determine which fish species were at risk of oil contamination, a real-time assessment of how and where the oil was moving was needed, because the wreck became a continual source of oil release for several weeks after the initial grounding. The newly developed methods and procedures used to detect whole oil during the sampling program will be presented in the Alaska Commercial Fisheries Water Quality Sampling Methods and Procedures Manual which is currently under development. The purpose of the manual is to provide instructions to spill managers while they try to determine where spilled oil has or has not been encountered. The manual will include a meaningful data set that can be analyzed in real time to assess oil movement and concentration. Sections on oil properties and processes will be included along with scientific water quality sampling methods for whole and dissolved phase oil to assess potential contamination of commercial fishery resources and gear in Alaska waters during an oil spill. The manual will present a general discussion of factors that should be considered when designing a sampling program after a spill. In order to implement Alaska's improved seafood safety measures, the spatial scope of spilled oil must be known. A water quality sampling program can provide state and federal fishery managers and food safety inspectors with important information as they identify at-risk fisheries. 11 refs., 7 figs.

  13. Using solvent-free sample preparation to promote protonation of poly(ethylene oxide)s with labile end-groups in matrix-assisted laser desorption/ionisation.

    Science.gov (United States)

    Mazarin, Michael; Phan, Trang N T; Charles, Laurence

    2008-12-01

    Protonation is usually required to observe intact ions during matrix-assisted laser desorption/ionization (MALDI) of polymers containing fragile end-groups while cation adduction induces chain-end degradation. These polymers, generally obtained via living free radical polymerization techniques, are terminated with a functionality in which a bond is prone to homolytic cleavage, as required by the polymerization process. A solvent-free sample preparation method was used here to avoid salt contaminant from the solvent traditionally used in the dried-droplet MALDI procedure. Solvent-based and solvent-free sample preparations were compared for a series of three poly(ethylene oxide) polymers functionalized with a labile end-group in a nitroxide-mediated polymerization reaction, using 2,4,6-trihydroxyacetophenone (THAP) as the matrix without any added salt. Intact oligomer ions could only be produced as protonated molecules in solvent-free MALDI while sodium adducts of degraded polymers were formed from the dried-droplet samples. Although MALDI analysis was performed at the laser threshold, fragmentation of protonated macromolecules was still observed to occur. However, in contrast to sodiated molecules, dissociation of protonated oligomers does not involve the labile C--ON bond of the end-group. As the macromolecule size increased, protonation appeared to be less efficient and sodium adduction became the dominant ionization process, although no sodium salt was added in the preparation. Formation of sodiated degraded macromolecules would be dictated by increasing cation affinity as the size of the oligomers increases and would reveal the presence of salts at trace levels in the MALDI samples.

  14. Comparison of green sample preparation techniques in the analysis of pyrethrins and pyrethroids in baby food by liquid chromatography-tandem mass spectrometry.

    Science.gov (United States)

    Petrarca, Mateus Henrique; Ccanccapa-Cartagena, Alexander; Masiá, Ana; Godoy, Helena Teixeira; Picó, Yolanda

    2017-05-12

    A new selective and sensitive liquid chromatography triple quadrupole mass spectrometry method was developed for simultaneous analysis of natural pyrethrins and synthetic pyrethroids residues in baby food. In this study, two sample preparation methods based on ultrasound-assisted dispersive liquid-liquid microextraction (UA-DLLME) and salting-out assisted liquid-liquid extraction (SALLE) were optimized, and then, compared regarding the performance criteria. Appropriate linearity in solvent and matrix-based calibrations, and suitable recoveries (75-120%) and precision (RSD values≤16%) were achieved for selected analytes by any of the sample preparation procedures. Both methods provided the analytical selectivity required for the monitoring of the insecticides in fruit-, cereal- and milk-based baby foods. SALLE, recognized by cost-effectiveness, and simple and fast execution, provided a lower enrichment factor, consequently, higher limits of quantification (LOQs) were obtained. Some of them too high to meet the strict legislation regarding baby food. Nonetheless, the combination of ultrasound and DLLME also resulted in a high sample throughput and environmental-friendly method, whose LOQs were lower than the default maximum residue limit (MRL) of 10μgkg -1 set by European Community for baby foods. In the commercial baby foods analyzed, cyhalothrin and etofenprox were detected in different samples, demonstrating the suitability of proposed method for baby food control. Copyright © 2017 Elsevier B.V. All rights reserved.

  15. Transmission Electron Microscopy (TEM) Sample Preparation of Si(1-x)Gex in c-Plane Sapphire Substrate

    Science.gov (United States)

    Kim, Hyun Jung; Choi, Sang H.; Bae, Hyung-Bin; Lee, Tae Woo

    2012-01-01

    The National Aeronautics and Space Administration-invented X-ray diffraction (XRD) methods, including the total defect density measurement method and the spatial wafer mapping method, have confirmed super hetero epitaxy growth for rhombohedral single crystalline silicon germanium (Si1-xGex) on a c-plane sapphire substrate. However, the XRD method cannot observe the surface morphology or roughness because of the method s limited resolution. Therefore the authors used transmission electron microscopy (TEM) with samples prepared in two ways, the focused ion beam (FIB) method and the tripod method to study the structure between Si1-xGex and sapphire substrate and Si1?xGex itself. The sample preparation for TEM should be as fast as possible so that the sample should contain few or no artifacts induced by the preparation. The standard sample preparation method of mechanical polishing often requires a relatively long ion milling time (several hours), which increases the probability of inducing defects into the sample. The TEM sampling of the Si1-xGex on sapphire is also difficult because of the sapphire s high hardness and mechanical instability. The FIB method and the tripod method eliminate both problems when performing a cross-section TEM sampling of Si1-xGex on c-plane sapphire, which shows the surface morphology, the interface between film and substrate, and the crystal structure of the film. This paper explains the FIB sampling method and the tripod sampling method, and why sampling Si1-xGex, on a sapphire substrate with TEM, is necessary.

  16. Molecularly imprinted polymers for sample preparation and biosensing in food analysis: Progress and perspectives

    DEFF Research Database (Denmark)

    Ashley, Jon; Shahbazi, Mohammad-Ali; Kant, Krishna

    2017-01-01

    Molecularly imprinted polymers (MIPs) are biomimetics which can selectively bind to analytes of interest. One of the most interesting areas where MIPs have shown the biggest potential is food analysis. MIPs have found use as sorbents in sample preparation attributed to the high selectivity and high...... the imprinting methods which are applicable for imprinting food templates, summarize the recent progress in using MIPs for preparing and analysing food samples, and discuss the current limitations in the commercialisation of MIPs technology. Finally, future perspectives will be given....

  17. An On-Target Desalting and Concentration Sample Preparation Protocol for MALDI-MS and MS/MS Analysis

    DEFF Research Database (Denmark)

    Zhang, Xumin; Wang, Quanhui; Lou, Xiaomin

    2012-01-01

    2DE coupled with MALDI-MS is one of the most widely used and powerful analytic technologies in proteomics study. The MALDI sample preparation method has been developed and optimized towards the combination of simplicity, sample-cleaning, and sample concentration since its introduction. Here we...... present a protocol of the so-called Sample loading, Matrix loading, and on-target Wash (SMW) method which fulfills the three criteria by taking advantage of the AnchorChip™ targets. Our method is extremely simple and no pre-desalting or concentration is needed when dealing with samples prepared from 2DE...

  18. Evaluation of slurry preparation procedures for the determination of mercury by axial view inductively coupled plasma optical emission spectrometry using on-line cold vapor generation

    International Nuclear Information System (INIS)

    Santos, Eder Jose dos; Herrmann, Amanda Beatriz; Antunes Vieira, Mariana; Azzolin Frescura, Vera Lucia; Curtius, Adilson Jose

    2005-01-01

    Five different slurry preparation procedures were tested, after grinding the solid samples to a particle size ≤53 μm: (1) using aqua regia plus HF, 30 min of sonication, standing time of 24 h followed by another 30 min of sonication; (2) same as the previous one, except that the standing time and the second ultrasound treatment were omitted; (3) same as the previous one, except that HF was not used; (4) same as the previous one, except that the aqua regia was replaced by nitric acid; (5) same as the previous one, except that the acid nitric was replaced by tetramethylammonium hydroxide (TMAH). The Hg vapor was generated on-line, and the emission signal intensity measured at 253.652 nm by axial view inductively coupled plasma optical emission spectrometry. Initially, four experimental conditions were optimized using a multivariate factorial analysis: the concentrations of HCl and of the reducing agent, NaBH 4 , used in the cold vapor generation, and two instrumental parameters, the plasma radiofrequency power and the carrier gas flow rate. The radiofrequency power was statistically significant, but limited to 1.2 kW for practical reasons. The procedures were applied to 11 biological and environmental materials. Both, the slurries and the filtrates were analyzed, using calibration solutions in the same medium as in the slurries. The first three procedures produced results in agreement with the certified values. The two last procedures, using nitric acid or TMHA could not be used for quantitative analysis. For practical reasons, Procedure 3, with a detection limit (3s, n=10) of 0.06 μg g -1 for a sample mass of 20 mg in a final volume of 15 mL is recommended. The relative standard deviations for mercury in the investigated materials, using the recommended procedure, were lower than 12.5%, indicating a good precision for slurry sampling. The recommended procedure is simple, rapid and robust

  19. A comparison of sample preparation strategies for biological tissues and subsequent trace element analysis using LA-ICP-MS.

    Science.gov (United States)

    Bonta, Maximilian; Török, Szilvia; Hegedus, Balazs; Döme, Balazs; Limbeck, Andreas

    2017-03-01

    Laser ablation-inductively coupled plasma-mass spectrometry (LA-ICP-MS) is one of the most commonly applied methods for lateral trace element distribution analysis in medical studies. Many improvements of the technique regarding quantification and achievable lateral resolution have been achieved in the last years. Nevertheless, sample preparation is also of major importance and the optimal sample preparation strategy still has not been defined. While conventional histology knows a number of sample pre-treatment strategies, little is known about the effect of these approaches on the lateral distributions of elements and/or their quantities in tissues. The technique of formalin fixation and paraffin embedding (FFPE) has emerged as the gold standard in tissue preparation. However, the potential use for elemental distribution studies is questionable due to a large number of sample preparation steps. In this work, LA-ICP-MS was used to examine the applicability of the FFPE sample preparation approach for elemental distribution studies. Qualitative elemental distributions as well as quantitative concentrations in cryo-cut tissues as well as FFPE samples were compared. Results showed that some metals (especially Na and K) are severely affected by the FFPE process, whereas others (e.g., Mn, Ni) are less influenced. Based on these results, a general recommendation can be given: FFPE samples are completely unsuitable for the analysis of alkaline metals. When analyzing transition metals, FFPE samples can give comparable results to snap-frozen tissues. Graphical abstract Sample preparation strategies for biological tissues are compared with regard to the elemental distributions and average trace element concentrations.

  20. Inexpensive multiplexed library preparation for megabase-sized genomes.

    Directory of Open Access Journals (Sweden)

    Michael Baym

    Full Text Available Whole-genome sequencing has become an indispensible tool of modern biology. However, the cost of sample preparation relative to the cost of sequencing remains high, especially for small genomes where the former is dominant. Here we present a protocol for rapid and inexpensive preparation of hundreds of multiplexed genomic libraries for Illumina sequencing. By carrying out the Nextera tagmentation reaction in small volumes, replacing costly reagents with cheaper equivalents, and omitting unnecessary steps, we achieve a cost of library preparation of $8 per sample, approximately 6 times cheaper than the standard Nextera XT protocol. Furthermore, our procedure takes less than 5 hours for 96 samples. Several hundred samples can then be pooled on the same HiSeq lane via custom barcodes. Our method will be useful for re-sequencing of microbial or viral genomes, including those from evolution experiments, genetic screens, and environmental samples, as well as for other sequencing applications including large amplicon, open chromosome, artificial chromosomes, and RNA sequencing.

  1. Ruthenium oxide/carbon composites with microporous or mesoporous carbon as support and prepared by two procedures. A comparative study as supercapacitor electrodes

    International Nuclear Information System (INIS)

    Pico, F.; Morales, E.; Fernandez, J.A.; Centeno, T.A.; Ibanez, J.; Rojas, R.M.; Amarilla, J.M.; Rojo, J.M.

    2009-01-01

    Composites are prepared by deposition of nanoparticles of RuO 2 .xH 2 O (1-4 nm) on two carbons: microporous carbon (1.3 nm of average micropore size) and mesoporous carbon (11 nm of average mesopore size). Two-preparation procedures are used: (i) procedure A consisting of repetitive impregnations of the carbons with RuCl 3 .0.5H 2 O solutions, and (ii) procedure B based on impregnation of the carbons with Ru(acac) 3 vapour. The procedure B leads to supported RuO 2 .xH 2 O particles that appear more crystalline than those obtained by the procedure A. Specific capacitance and specific surface area of the composites are discussed as functions of the RuO 2 content, and different dependences for the composites derived from the two carbons are found. Mesoporous carbon is better support than microporous carbon. Procedure A leads to supported RuO 2 .xH 2 O particles with higher specific capacitance than the particles deposited by procedure B

  2. Ruthenium oxide/carbon composites with microporous or mesoporous carbon as support and prepared by two procedures. A comparative study as supercapacitor electrodes

    Energy Technology Data Exchange (ETDEWEB)

    Pico, F. [Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Cientificas (CSIC), Sor Juana Ines de la Cruz 3, Cantoblanco, E-28049-Madrid (Spain); Morales, E. [Instituto de Ciencia y Tecnologia de Polimeros (ICTP), CSIC, Juan de la Cierva 3, E-28006-Madrid (Spain); Fernandez, J.A.; Centeno, T.A. [Instituto Nacional del Carbon (INCAR), CSIC, Francisco Pintado Fe 26, E-33011-Oviedo (Spain); Ibanez, J. [Centro Nacional de Investigaciones Metalurgicas (CENIM), CSIC, Avda. Gregorio del Amo 8, E-28040-Madrid (Spain); Rojas, R.M.; Amarilla, J.M. [Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Cientificas (CSIC), Sor Juana Ines de la Cruz 3, Cantoblanco, E-28049-Madrid (Spain); Rojo, J.M. [Instituto de Ciencia de Materiales de Madrid (ICMM), Consejo Superior de Investigaciones Cientificas (CSIC), Sor Juana Ines de la Cruz 3, Cantoblanco, E-28049-Madrid (Spain)], E-mail: jmrojo@icmm.csic.es

    2009-03-01

    Composites are prepared by deposition of nanoparticles of RuO{sub 2}.xH{sub 2}O (1-4 nm) on two carbons: microporous carbon (1.3 nm of average micropore size) and mesoporous carbon (11 nm of average mesopore size). Two-preparation procedures are used: (i) procedure A consisting of repetitive impregnations of the carbons with RuCl{sub 3}.0.5H{sub 2}O solutions, and (ii) procedure B based on impregnation of the carbons with Ru(acac){sub 3} vapour. The procedure B leads to supported RuO{sub 2}.xH{sub 2}O particles that appear more crystalline than those obtained by the procedure A. Specific capacitance and specific surface area of the composites are discussed as functions of the RuO{sub 2} content, and different dependences for the composites derived from the two carbons are found. Mesoporous carbon is better support than microporous carbon. Procedure A leads to supported RuO{sub 2}.xH{sub 2}O particles with higher specific capacitance than the particles deposited by procedure B.

  3. Procedures for the collection and preservation of groundwater and surface water samples and for the installation of monitoring wells

    International Nuclear Information System (INIS)

    Korte, N.; Kearl, P.

    1984-01-01

    Proper sampling procedures are essential for a successful water-quality monitoring program. It must be emphasized, however, that it is impossible to maintain absolutely in-situ conditions when collecting and preserving a water sample, whether from a flowing stream or an aquifer. Consequently, the most that can reasonably be expected is to collect a best possible sample with minimal disturbance. This document describes procedures for installing monitoring wells and for collecting samples of surface water and groundwater. The discussion of monitoring wells includes mention of multilevel sampling and a general overview of vadose-zone monitoring. Guidelines for well installation are presented in detail. The discussion of water-sample collection contains evaluations of sampling pumps, filtration equipment, and sample containers. Sample-preservation techniques, as published by several government and private sources, are reviewed. Finally, step-by-step procedures for collection of water samples are provided; these procedures address such considerations as necessary equipment, field operations, and written documentation. Separate procedures are also included for the collection of samples for determination of sulfide and for reactive aluminum. The report concludes with a brief discussion of adverse sampling, conditions that may significantly affect the quality of the data. Appendix A presents a rationale for the development and use of statistical considerations in water sampling to ensure a more complete water quality monitoring program. 51 references, 9 figures, 4 tables

  4. A recommended procedure for establishing the source level relationships between heroin case samples of unknown origins

    Directory of Open Access Journals (Sweden)

    Kar-Weng Chan

    2014-06-01

    Full Text Available A recent concern of how to reliably establish the source level relationships of heroin case samples is addressed in this paper. Twenty-two trafficking heroin case samples of unknown origins seized from two major regions (Kuala Lumpur and Penang in Malaysia were studied. A procedure containing six major steps was followed to analyze and classify these samples. Subsequently, with the aid of statistical control samples, reliability of the clustering result was assessed. The final outcome reveals that the samples seized from the two regions in 2013 had highly likely originated from two different sources. Hence, the six-step procedure is sufficient for any chemist who attempts to assess the relative source level relationships of heroin samples.

  5. One Sample, One Shot - Evaluation of sample preparation protocols for the mass spectrometric proteome analysis of human bile fluid without extensive fractionation.

    Science.gov (United States)

    Megger, Dominik A; Padden, Juliet; Rosowski, Kristin; Uszkoreit, Julian; Bracht, Thilo; Eisenacher, Martin; Gerges, Christian; Neuhaus, Horst; Schumacher, Brigitte; Schlaak, Jörg F; Sitek, Barbara

    2017-02-10

    The proteome analysis of bile fluid represents a promising strategy to identify biomarker candidates for various diseases of the hepatobiliary system. However, to obtain substantive results in biomarker discovery studies large patient cohorts necessarily need to be analyzed. Consequently, this would lead to an unmanageable number of samples to be analyzed if sample preparation protocols with extensive fractionation methods are applied. Hence, the performance of simple workflows allowing for "one sample, one shot" experiments have been evaluated in this study. In detail, sixteen different protocols implying modifications at the stages of desalting, delipidation, deglycosylation and tryptic digestion have been examined. Each method has been individually evaluated regarding various performance criteria and comparative analyses have been conducted to uncover possible complementarities. Here, the best performance in terms of proteome coverage has been assessed for a combination of acetone precipitation with in-gel digestion. Finally, a mapping of all obtained protein identifications with putative biomarkers for hepatocellular carcinoma (HCC) and cholangiocellular carcinoma (CCC) revealed several proteins easily detectable in bile fluid. These results can build the basis for future studies with large and well-defined patient cohorts in a more disease-related context. Human bile fluid is a proximal body fluid and supposed to be a potential source of disease markers. However, due to its biochemical composition, the proteome analysis of bile fluid still represents a challenging task and is therefore mostly conducted using extensive fractionation procedures. This in turn leads to a high number of mass spectrometric measurements for one biological sample. Considering the fact that in order to overcome the biological variability a high number of biological samples needs to be analyzed in biomarker discovery studies, this leads to the dilemma of an unmanageable number of

  6. Preparation of 45 Ca (HDEHP)n and (C8H15O2)2 samples for liquid scintillation counting, compared to 45CaCl2 results

    International Nuclear Information System (INIS)

    Rodriguez Barquero, L.; Los Arcos Merino, J.M.; Grau Malonda, A.

    1994-01-01

    A procedure for preparation of liquid scintillation counting organic samples of the Di-2-ethylhexyl phosphate calcium complex and the 2-ethyhexanoate calcium salt, labelled with ''45 Ca, is described. The chemical quench, the counting stability and spectral evolution of both compounds is studied in six scintillators, Toluene, Toluene-alcohol, Dioxane-napthalhene, Hisafe II, Ultima-Gold and Instagel, and compared to results obtained from a commercial solution of ''45 CaCl 2

  7. Analytical sample preparation strategies for the determination of antimalarial drugs in human whole blood, plasma and urine

    DEFF Research Database (Denmark)

    Casas, Monica Escolà; Hansen, Martin; Krogh, Kristine A

    2014-01-01

    the available sample preparation strategies combined with liquid chromatographic (LC) analysis to determine antimalarials in whole blood, plasma and urine published over the last decade. Sample preparation can be done by protein precipitation, solid-phase extraction, liquid-liquid extraction or dilution. After...

  8. Guide to preparing SAND Reports and other communication products.

    Energy Technology Data Exchange (ETDEWEB)

    2009-02-01

    This guide describes the R&A process, Common Look and Feel requirements, and preparation and publishing procedures for communication products at Sandia National Laboratories. Samples of forms and examples of published communications products are provided.

  9. In-situ transmission electron microscopy of the solid-phase epitaxial growth of GaAs: sample preparation and artifact characterization

    International Nuclear Information System (INIS)

    Llewellyn, D.J.; Llewellyn, D.J.; Belay, K.B.; Ridgway, M.C.

    1998-01-01

    In-situ transmission electron microscopy (TEM) has been used to characterize the solid phase epitaxial growth of amorphized GaAs at a temperature of 260 deg C. To maximize heat transfer from the heated holder to the sample and minimize electron-irradiation induced artifacts, non-conventional methodologies were utilized for the preparation of cross-sectional samples. GaAs 3x1 mm rectangular wafers were cleaved then glued face-to-face to form a wafer stack size of 3x3 mm while maintaining the TEM region at the center. This stack was subsequently polished on the cross-section to a thickness of ∼ 200 μm. A 3 mm disc was then cut perpendicular to the cross-section using a Gatan ultrasonic cutter. The disc was polished then dimpled on both sides to a thickness of ∼ 15 μm. This was ion-beam milled at liquid nitrogen temperature to an electron-transparent layer. From a comparison of in-situ and ex-situ measurements of the recrystallization rate, the actual sample temperature during in-situ characterization was estimated to deviate by ≤ 20 deg C from that of the heated holder. The influence of electron-irradiation was found to be negligible by comparing the recrystallization rate and microstructure of irradiated and unirradiated regions of comparable thickness. Similarly, the influence of the 'thin-foil effect' was found to be negligible by comparing the recrystallization rate and microstructure of thick and thin regions, the former determined after the removal of the sample from the microscope and further ion-beam milling of tens of microns of material. In conclusion, the potential influence of artifacts during in-situ TEM can be minimized by the appropriate choice of sample preparation procedures. (authors)

  10. A Simple and Reproducible Method to Prepare Membrane Samples from Freshly Isolated Rat Brain Microvessels.

    Science.gov (United States)

    Brzica, Hrvoje; Abdullahi, Wazir; Reilly, Bianca G; Ronaldson, Patrick T

    2018-05-07

    The blood-brain barrier (BBB) is a dynamic barrier tissue that responds to various pathophysiological and pharmacological stimuli. Such changes resulting from these stimuli can greatly modulate drug delivery to the brain and, by extension, cause considerable challenges in the treatment of central nervous system (CNS) diseases. Many BBB changes that affect pharmacotherapy, involve proteins that are localized and expressed at the level of endothelial cells. Indeed, such knowledge on BBB physiology in health and disease has sparked considerable interest in the study of these membrane proteins. From a basic science research standpoint, this implies a requirement for a simple but robust and reproducible method for isolation of microvessels from brain tissue harvested from experimental animals. In order to prepare membrane samples from freshly isolated microvessels, it is essential that sample preparations be enriched in endothelial cells but limited in the presence of other cell types of the neurovascular unit (i.e., astrocytes, microglia, neurons, pericytes). An added benefit is the ability to prepare samples from individual animals in order to capture the true variability of protein expression in an experimental population. In this manuscript, details regarding a method that is utilized for isolation of rat brain microvessels and preparation of membrane samples are provided. Microvessel enrichment, from samples derived, is achieved by using four centrifugation steps where dextran is included in the sample buffer. This protocol can easily be adapted by other laboratories for their own specific applications. Samples generated from this protocol have been shown to yield robust experimental data from protein analysis experiments that can greatly aid the understanding of BBB responses to physiological, pathophysiological, and pharmacological stimuli.

  11. Improvement of a sample preparation method assisted by sodium deoxycholate for mass-spectrometry-based shotgun membrane proteomics.

    Science.gov (United States)

    Lin, Yong; Lin, Haiyan; Liu, Zhonghua; Wang, Kunbo; Yan, Yujun

    2014-11-01

    In current shotgun-proteomics-based biological discovery, the identification of membrane proteins is a challenge. This is especially true for integral membrane proteins due to their highly hydrophobic nature and low abundance. Thus, much effort has been directed at sample preparation strategies such as use of detergents, chaotropes, and organic solvents. We previously described a sample preparation method for shotgun membrane proteomics, the sodium deoxycholate assisted method, which cleverly circumvents many of the challenges associated with traditional sample preparation methods. However, the method is associated with significant sample loss due to the slightly weaker extraction/solubilization ability of sodium deoxycholate when it is used at relatively low concentrations such as 1%. Hence, we present an enhanced sodium deoxycholate sample preparation strategy that first uses a high concentration of sodium deoxycholate (5%) to lyse membranes and extract/solubilize hydrophobic membrane proteins, and then dilutes the detergent to 1% for a more efficient digestion. We then applied the improved method to shotgun analysis of proteins from rat liver membrane enriched fraction. Compared with other representative sample preparation strategies including our previous sodium deoxycholate assisted method, the enhanced sodium deoxycholate method exhibited superior sensitivity, coverage, and reliability for the identification of membrane proteins particularly those with high hydrophobicity and/or multiple transmembrane domains. © 2014 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  12. A radiochemical procedure for the determination of Po-210 in environmental samples

    International Nuclear Information System (INIS)

    Godoy, J.M.; Schuettelkopf, H.

    1980-07-01

    A radiochemical procedure for the determination of Po-210 in environmental samples was developed. Soil, sediments, filter materials, plants, water and food samples can be analyzed for Po-210. Wet ashing is achieved with HNO 3 + H 2 O 2 or HCl + HNO 3 . To separate disturbing substances, a coprecipitation with Te is used for sample materials containing silica. Po-210 deposition from HCl solution on Ag platelets with other sample materials is possible directly. Deposited Po-210 is counted by α-spectrometry. For chemical yield determination Po-208 is added, yields range between 60% and 100%. A lower detection limit of about 0,002 pCi Po-210/sample is achievable. (orig./HP) [de

  13. M3FT-17OR0301070211 - Preparation of Hot Isostatically Pressed AgZ Waste Form Samples

    Energy Technology Data Exchange (ETDEWEB)

    Jubin, Robert Thomas [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Bruffey, Stephanie H. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States); Jordan, Jacob A. [Oak Ridge National Lab. (ORNL), Oak Ridge, TN (United States)

    2017-10-01

    The production of radioactive iodine-bearing waste forms that exhibit long-term stability and are suitable for permanent geologic disposal has been the subject of substantial research interest. One potential method of iodine waste form production is hot isostatic pressing (HIP). Recent studies at Oak Ridge National Laboratory (ORNL) have investigated the conversion of iodine-loaded silver mordenite (I-AgZ) directly to a waste form by HIP. ORNL has performed HIP with a variety of sample compositions and pressing conditions. The base mineral has varied among AgZ (in pure and engineered forms), silver-exchanged faujasite, and silverexchanged zeolite A. Two iodine loading methods, occlusion and chemisorption, have been explored. Additionally, the effects of variations in temperature and pressure of the process have been examined, with temperature ranges of 525°C–1,100°C and pressure ranges of 100–300 MPa. All of these samples remain available to collaborators upon request. The sample preparation detailed in this document is an extension of that work. In addition to previously prepared samples, this report documents the preparation of additional samples to support stability testing. These samples include chemisorbed I-AgZ and pure AgI. Following sample preparation, each sample was processed by HIP by American Isostatic Presses Inc. and returned to ORNL for storage. ORNL will store the samples until they are requested by collaborators for durability testing. The sample set reported here will support waste form durability testing across the national laboratories and will provide insight into the effects of varied iodine content on iodine retention by the produced waste form and on potential improvements in waste form durability provided by the zeolite matrix.

  14. Collection and preparation of marine samples for radionuclide analysis

    International Nuclear Information System (INIS)

    Holm, E.

    1997-01-01

    The ultimate goal of research in radioecology is to be able to predict the pathways of radioactive material in the environment and hence estimate possible doses to the population in various regions. Knowledge of levels of contamination are necessary to maintain control of operations of nuclear facilities. Correct methods of sample collection, handling and preparation are among the most important parts for a correct assessment. On basis of the final results of radionuclide concentrations, scientific, medical and political decisions are taken. (author)

  15. Sulfonate-terminated carbosilane dendron-coated nanotubes: a greener point of view in protein sample preparation.

    Science.gov (United States)

    González-García, Estefanía; Gutiérrez Ulloa, Carlos E; de la Mata, Francisco Javier; Marina, María Luisa; García, María Concepción

    2017-09-01

    Reduction or removal of solvents and reagents in protein sample preparation is a requirement. Dendrimers can strongly interact with proteins and have great potential as a greener alternative to conventional methods used in protein sample preparation. This work proposes the use of single-walled carbon nanotubes (SWCNTs) functionalized with carbosilane dendrons with sulfonate groups for protein sample preparation and shows the successful application of the proposed methodology to extract proteins from a complex matrix. SEM images of nanotubes and mixtures of nanotubes and proteins were taken. Moreover, intrinsic fluorescence intensity of proteins was monitored to observe the most significant interactions at increasing dendron generations under neutral and basic pHs. Different conditions for the disruption of interactions between proteins and nanotubes after protein extraction and different concentrations of the disrupting reagent and the nanotube were also tried. Compatibility of extraction and disrupting conditions with the enzymatic digestion of proteins for obtaining bioactive peptides was also studied. Finally, sulfonate-terminated carbosilane dendron-coated SWCNTs enabled the extraction of proteins from a complex sample without using non-environmentally friendly solvents that were required so far. Graphical Abstract Green protein extraction from a complex sample employing carbosilane dendron coated nanotubes.

  16. Application of empore TM strontium rad disks to the analysis of radiostrontium in environmental water samples

    International Nuclear Information System (INIS)

    Smith, L.L.; Seely, D.C.; Shannon, R.T.

    1996-01-01

    A solid phase extraction method for analyzing radioactive strontium in surface, ground, and drinking waters is presented. Strontium is simply isolated by pulling an acidified sample aliquot through an Empore TM strontium rad disk with a vacuum, and the disk is subsequently assayed for beta activity. The method is efficient, safe, reliable, and potentially field deployable. Sample preparation and counting source preparation may be condensed into a single procedure, thereby improving efficiency and eliminating many potential sources of laboratory error. Moreover, many of the hazardous chemicals associated with traditional strontium procedures are eliminated. Samples are easily batched, and a one-liter sample may be prepared with as little as 20 min of effort. For a one-liter aqueous sample, up to 3 mg of strontium can be retained by the disks. Chemical and radiometric interferences are discussed. (orig.)

  17. Sampling procedures and tables

    International Nuclear Information System (INIS)

    Franzkowski, R.

    1980-01-01

    Characteristics, defects, defectives - Sampling by attributes and by variables - Sample versus population - Frequency distributions for the number of defectives or the number of defects in the sample - Operating characteristic curve, producer's risk, consumer's risk - Acceptable quality level AQL - Average outgoing quality AOQ - Standard ISQ 2859 - Fundamentals of sampling by variables for fraction defective. (RW)

  18. A procedure for the determination of Po-210 in water samples by alpha spectrometry

    International Nuclear Information System (INIS)

    2009-01-01

    Reliable, comparable and 'fit for purpose' results are an essential requirement for any decision based on analytical measurements. For the analyst, the availability of tested and validated analytical procedures is a extremely important tool for production of such analytical measurements. For maximum utility, such procedures should be comprehensive, clearly formulated, and readily available to both the analyst and the customer for reference. Since 2004 the Environment programme of the IAEA has included activities aimed at the development of a set of procedures for the determination of radionuclides in terrestrial environmental samples. In the case of 210 Po, this started with the collection and review of about 130 papers from the scientific literature. Based on this review, two candidate methods for the chemical separation of 210 Po from water samples were selected for testing, refinement and validation in accordance with ISO guidelines. A comprehensive methodology for calculation of results including quantification of measurement uncertainty was also developed. This report presents the final procedure which was developed based on that work

  19. Modified FlowCAM procedure for quantifying size distribution of zooplankton with sample recycling capacity.

    Directory of Open Access Journals (Sweden)

    Esther Wong

    Full Text Available We have developed a modified FlowCAM procedure for efficiently quantifying the size distribution of zooplankton. The modified method offers the following new features: 1 prevents animals from settling and clogging with constant bubbling in the sample container; 2 prevents damage to sample animals and facilitates recycling by replacing the built-in peristaltic pump with an external syringe pump, in order to generate negative pressure, creates a steady flow by drawing air from the receiving conical flask (i.e. vacuum pump, and transfers plankton from the sample container toward the main flowcell of the imaging system and finally into the receiving flask; 3 aligns samples in advance of imaging and prevents clogging with an additional flowcell placed ahead of the main flowcell. These modifications were designed to overcome the difficulties applying the standard FlowCAM procedure to studies where the number of individuals per sample is small, and since the FlowCAM can only image a subset of a sample. Our effective recycling procedure allows users to pass the same sample through the FlowCAM many times (i.e. bootstrapping the sample in order to generate a good size distribution. Although more advanced FlowCAM models are equipped with syringe pump and Field of View (FOV flowcells which can image all particles passing through the flow field; we note that these advanced setups are very expensive, offer limited syringe and flowcell sizes, and do not guarantee recycling. In contrast, our modifications are inexpensive and flexible. Finally, we compared the biovolumes estimated by automated FlowCAM image analysis versus conventional manual measurements, and found that the size of an individual zooplankter can be estimated by the FlowCAM image system after ground truthing.

  20. Development of the methodology of sample preparation to X-ray diffractometry of clay minerals at Petrobras Research Center

    International Nuclear Information System (INIS)

    Alves, D.B.

    1987-01-01

    Various procedures can be used in the analysis of the clay mineral content of rocks by X-ray diffraction. This article describes the principal ones and discusses those adopted in the X-ray clay mineral laboratory of the PETROBRAS Research Center (CENPES) in Rio de Janeiro. This article presents the methodology used and provides users with information about its application and limitations. The methodology has been developed to study polymineral samples. The aim to identify clay mineral groups and to estimate their relative proportions. Of the four main steps of this analysis - separation and concentration of clay minerals, preparation of oriented specimens, X-ray irradiation under standard conditions and interpretation of X-ray diffraction patterns - only the first three are discussed here. Clay minerals occur mainly in the [pt

  1. Minimizing technical variation during sample preparation prior to label-free quantitative mass spectrometry.

    Science.gov (United States)

    Scheerlinck, E; Dhaenens, M; Van Soom, A; Peelman, L; De Sutter, P; Van Steendam, K; Deforce, D

    2015-12-01

    Sample preparation is the crucial starting point to obtain high-quality mass spectrometry data and can be divided into two main steps in a bottom-up proteomics approach: cell/tissue lysis with or without detergents and a(n) (in-solution) digest comprising denaturation, reduction, alkylation, and digesting of the proteins. Here, some important considerations, among others, are that the reagents used for sample preparation can inhibit the digestion enzyme (e.g., 0.1% sodium dodecyl sulfate [SDS] and 0.5 M guanidine HCl), give rise to ion suppression (e.g., polyethylene glycol [PEG]), be incompatible with liquid chromatography-tandem mass spectrometry (LC-MS/MS) (e.g., SDS), and can induce additional modifications (e.g., urea). Taken together, all of these irreproducible effects are gradually becoming a problem when label-free quantitation of the samples is envisioned such as during the increasingly popular high-definition mass spectrometry (HDMS(E)) and sequential window acquisition of all theoretical fragment ion spectra (SWATH) data-independent acquisition strategies. Here, we describe the detailed validation of a reproducible method with sufficient protein yield for sample preparation without any known LC-MS/MS interfering substances by using 1% sodium deoxycholate (SDC) during both cell lysis and in-solution digest. Copyright © 2015 The Authors. Published by Elsevier Inc. All rights reserved.

  2. Adolescent test or procedure preparation

    Science.gov (United States)

    ... someone else) during the procedure Playing hand-held video games Using guided imagery Trying other distractions, such as ... effects the test may cause. Older teens may benefit from videos that show adolescents of the same age explaining ...

  3. Challenges of biological sample preparation for SIMS imaging of elements and molecules at subcellular resolution

    International Nuclear Information System (INIS)

    Chandra, Subhash

    2008-01-01

    Secondary ion mass spectrometry (SIMS) based imaging techniques capable of subcellular resolution characterization of elements and molecules are becoming valuable tools in many areas of biology and medicine. Due to high vacuum requirements of SIMS, the live cells cannot be analyzed directly in the instrument. The sample preparation, therefore, plays a critical role in preserving the native chemical composition for SIMS analysis. This work focuses on the evaluation of frozen-hydrated and frozen freeze-dried sample preparations for SIMS studies of cultured cells with a CAMECA IMS-3f dynamic SIMS ion microscope instrument capable of producing SIMS images with a spatial resolution of 500 nm. The sandwich freeze-fracture method was used for fracturing the cells. The complimentary fracture planes in the plasma membrane were characterized by field-emission secondary electron microscopy (FESEM) in the frozen-hydrated state. The cells fractured at the dorsal surface were used for SIMS analysis. The frozen-hydrated SIMS analysis of individual cells under dynamic primary ion beam (O 2 + ) revealed local secondary ion signal enhancements correlated with the water image signals of 19 (H 3 O) + . A preferential removal of water from the frozen cell matrix in the Z-axis was also observed. These complications render the frozen-hydrated sample type less desirable for subcellular dynamic SIMS studies. The freeze-drying of frozen-hydrated cells, either inside the instrument or externally in a freeze-drier, allowed SIMS imaging of subcellular chemical composition. Morphological evaluations of fractured freeze-dried cells with SEM and confocal laser scanning microscopy (CLSM) revealed well-preserved mitochondria, Golgi apparatus, and stress fibers. SIMS analysis of fractured freeze-dried cells revealed well-preserved chemical composition of even the most highly diffusible ions like K + and Na + in physiologically relevant concentrations. The high K-low Na signature in individual cells

  4. Challenges of biological sample preparation for SIMS imaging of elements and molecules at subcellular resolution

    Science.gov (United States)

    Chandra, Subhash

    2008-12-01

    Secondary ion mass spectrometry (SIMS) based imaging techniques capable of subcellular resolution characterization of elements and molecules are becoming valuable tools in many areas of biology and medicine. Due to high vacuum requirements of SIMS, the live cells cannot be analyzed directly in the instrument. The sample preparation, therefore, plays a critical role in preserving the native chemical composition for SIMS analysis. This work focuses on the evaluation of frozen-hydrated and frozen freeze-dried sample preparations for SIMS studies of cultured cells with a CAMECA IMS-3f dynamic SIMS ion microscope instrument capable of producing SIMS images with a spatial resolution of 500 nm. The sandwich freeze-fracture method was used for fracturing the cells. The complimentary fracture planes in the plasma membrane were characterized by field-emission secondary electron microscopy (FESEM) in the frozen-hydrated state. The cells fractured at the dorsal surface were used for SIMS analysis. The frozen-hydrated SIMS analysis of individual cells under dynamic primary ion beam (O 2+) revealed local secondary ion signal enhancements correlated with the water image signals of 19(H 3O) +. A preferential removal of water from the frozen cell matrix in the Z-axis was also observed. These complications render the frozen-hydrated sample type less desirable for subcellular dynamic SIMS studies. The freeze-drying of frozen-hydrated cells, either inside the instrument or externally in a freeze-drier, allowed SIMS imaging of subcellular chemical composition. Morphological evaluations of fractured freeze-dried cells with SEM and confocal laser scanning microscopy (CLSM) revealed well-preserved mitochondria, Golgi apparatus, and stress fibers. SIMS analysis of fractured freeze-dried cells revealed well-preserved chemical composition of even the most highly diffusible ions like K + and Na + in physiologically relevant concentrations. The high K-low Na signature in individual cells

  5. 14C sample preparation for AMS microdosing studies at Lund University using online combustion and septa-sealed vials

    Science.gov (United States)

    Sydoff, Marie; Stenström, Kristina

    2010-04-01

    The Department of Physics at Lund University is participating in a European Union project called EUMAPP (European Union Microdose AMS Partnership Programme), in which sample preparation and accelerator mass spectrometry (AMS) measurements of biological samples from microdosing studies have been made. This paper describes a simplified method of converting biological samples to solid graphite for 14C analysis with AMS. The method is based on online combustion of the samples, and reduction of CO 2 in septa-sealed vials. The septa-sealed vials and disposable materials are used to eliminate sample cross-contamination. Measurements of ANU and Ox I standards show deviations of 2% and 3%, respectively, relative to reference values. This level of accuracy is sufficient for biological samples from microdosing studies. Since the method has very few handling steps from sample to graphite, the risk of failure during the sample preparation process is minimized, making the method easy to use in routine preparation of samples.

  6. 14C sample preparation for AMS microdosing studies at Lund University using online combustion and septa-sealed vials

    International Nuclear Information System (INIS)

    Sydoff, Marie; Stenstroem, Kristina

    2010-01-01

    The Department of Physics at Lund University is participating in a European Union project called EUMAPP (European Union Microdose AMS Partnership Programme), in which sample preparation and accelerator mass spectrometry (AMS) measurements of biological samples from microdosing studies have been made. This paper describes a simplified method of converting biological samples to solid graphite for 14 C analysis with AMS. The method is based on online combustion of the samples, and reduction of CO 2 in septa-sealed vials. The septa-sealed vials and disposable materials are used to eliminate sample cross-contamination. Measurements of ANU and Ox I standards show deviations of 2% and 3%, respectively, relative to reference values. This level of accuracy is sufficient for biological samples from microdosing studies. Since the method has very few handling steps from sample to graphite, the risk of failure during the sample preparation process is minimized, making the method easy to use in routine preparation of samples.

  7. Effects of blood sample handling procedures on measurable inflammatory markers in plasma, serum and dried blood spot samples

    DEFF Research Database (Denmark)

    Skogstrand, K.; Thorsen, P.; Vogel, I.

    2008-01-01

    of whole blood samples at low temperatures and rapid isolation of plasma and serum. Effects of different handling procedures for all markers studied are given. DBSS proved to be a robust and convenient way to handle samples for immunoassay analysis of inflammatory markers in whole blood Udgivelsesdato......The interests in monitoring inflammation by immunoassay determination of blood inflammatory markers call for information on the stability of these markers in relation to the handling of blood samples. The increasing use of stored biobank samples for such ventures that may have been collected...... and stored for other purposes, justifies the study hereof. Blood samples were stored for 0, 4, 24, and 48 h at 4 degrees C, room temperature (RT), and at 35 degrees C, respectively, before they were separated into serum or plasma and frozen. Dried blood spot samples (DBSS) were stored for 0, 1, 2, 3, 7...

  8. The role of sample preparation in interpretation of trace element concentration variability in moss bioindication studies

    Science.gov (United States)

    Migaszewski, Z.M.; Lamothe, P.J.; Crock, J.G.; Galuszka, A.; Dolegowska, S.

    2011-01-01

    Trace element concentrations in plant bioindicators are often determined to assess the quality of the environment. Instrumental methods used for trace element determination require digestion of samples. There are different methods of sample preparation for trace element analysis, and the selection of the best method should be fitted for the purpose of a study. Our hypothesis is that the method of sample preparation is important for interpretation of the results. Here we compare the results of 36 element determinations performed by ICP-MS on ashed and on acid-digested (HNO3, H2O2) samples of two moss species (Hylocomium splendens and Pleurozium schreberi) collected in Alaska and in south-central Poland. We found that dry ashing of the moss samples prior to analysis resulted in considerably lower detection limits of all the elements examined. We also show that this sample preparation technique facilitated the determination of interregional and interspecies differences in the chemistry of trace elements. Compared to the Polish mosses, the Alaskan mosses displayed more positive correlations of the major rock-forming elements with ash content, reflecting those elements' geogenic origin. Of the two moss species, P. schreberi from both Alaska and Poland was also highlighted by a larger number of positive element pair correlations. The cluster analysis suggests that the more uniform element distribution pattern of the Polish mosses primarily reflects regional air pollution sources. Our study has shown that the method of sample preparation is an important factor in statistical interpretation of the results of trace element determinations. ?? 2010 Springer-Verlag.

  9. Research And Establishment Of The Analytical Procedure For/Of Sr-90 In Milk Samples

    International Nuclear Information System (INIS)

    Tran Thi Tuyet Mai; Duong Duc Thang; Nguyen Thi Linh; Bui Thi Anh Duong

    2014-01-01

    Sr-90 is an indicator for the transfer radionuclides from environment to human. This work was setup to build a procedure for Sr-90 determination in main popular foodstuff and focus to fresh milk. The deal of this work was establish procedure for Sr-90 , assessment for chemical yield and test sample of Vietnam fresh milk, also in this work, the QA, QC for the procedure was carried out using standard sample of IAEA. The work has been completed for the procedure of determination Sr-90 in milk. The chemical yield of recovery for Y-90 and Sr-90 were at 46.76 % ±1.25% and 0.78 ± 0.086, respectively. The QA & QC program was carried out using reference material IAEA-373. The result parse is appropriate equally and well agreement with the certificate value. Three reference samples were analyses with 15 measurements. The results of Sr-90 concentration after processing statistics given a value at 3.69 Bq/kg with uncertainty of 0.23 Bq/kg. The certificate of IAEA-154 for Sr-90 (half live 28.8 year) is the 6.9 Bq/kg, with the range 95% Confidence Interval as (6.0 -8.0 ) Bq/kg at 31st August 1987. After adjusting decay, the radioactivity at this time is 3.67 Bq/kg. It means that such the result of this work was perfect matching the value of stock index IAEA. Five Vietnam fresh milk samples were analyzed for Sr-90, the specific radioactivity of Sr-90 in milk were in a range from 0.032 to 0.041 Bq/l. (author)

  10. Sample preparation method for ICP-MS measurement of 99Tc in a large amount of environmental samples

    International Nuclear Information System (INIS)

    Kondo, M.; Seki, R.

    2002-01-01

    Sample preparation for measurement of 99 Tc in a large amount of soil and water samples by ICP-MS has been developed using 95m Tc as a yield tracer. This method is based on the conventional method for a small amount of soil samples using incineration, acid digestion, extraction chromatography (TEVA resin) and ICP-MS measurement. Preliminary concentration of Tc has been introduced by co-precipitation with ferric oxide. The matrix materials in a large amount of samples were more sufficiently removed with keeping the high recovery of Tc than previous method. The recovery of Tc was 70-80% for 100 g soil samples and 60-70% for 500 g of soil and 500 L of water samples. The detection limit of this method was evaluated as 0.054 mBq/kg in 500 g soil and 0.032 μBq/L in 500 L water. The determined value of 99 Tc in the IAEA-375 (soil sample collected near the Chernobyl Nuclear Reactor) was 0.25 ± 0.02 Bq/kg. (author)

  11. Evaluation of accuracy in implant site preparation performed in single- or multi-step drilling procedures.

    Science.gov (United States)

    Marheineke, Nadine; Scherer, Uta; Rücker, Martin; von See, Constantin; Rahlf, Björn; Gellrich, Nils-Claudius; Stoetzer, Marcus

    2018-06-01

    Dental implant failure and insufficient osseointegration are proven results of mechanical and thermal damage during the surgery process. We herein performed a comparative study of a less invasive single-step drilling preparation protocol and a conventional multiple drilling sequence. Accuracy of drilling holes was precisely analyzed and the influence of different levels of expertise of the handlers and additional use of drill template guidance was evaluated. Six experimental groups, deployed in an osseous study model, were representing template-guided and freehanded drilling actions in a stepwise drilling procedure in comparison to a single-drill protocol. Each experimental condition was studied by the drilling actions of respectively three persons without surgical knowledge as well as three highly experienced oral surgeons. Drilling actions were performed and diameters were recorded with a precision measuring instrument. Less experienced operators were able to significantly increase the drilling accuracy using a guiding template, especially when multi-step preparations are performed. Improved accuracy without template guidance was observed when experienced operators were executing single-step versus multi-step technique. Single-step drilling protocols have shown to produce more accurate results than multi-step procedures. The outcome of any protocol can be further improved by use of guiding templates. Operator experience can be a contributing factor. Single-step preparations are less invasive and are promoting osseointegration. Even highly experienced surgeons are achieving higher levels of accuracy by combining this technique with template guidance. Hereby template guidance enables a reduction of hands-on time and side effects during surgery and lead to a more predictable clinical diameter.

  12. Sampling procedure in a willow plantation for estimation of moisture content

    DEFF Research Database (Denmark)

    Nielsen, Henrik Kofoed; Lærke, Poul Erik; Liu, Na

    2015-01-01

    Heating value and fuel quality of wood is closely connected to moisture content. In this work the variation of moisture content (MC) of short rotation coppice (SRC) willow shoots is described for five clones during one harvesting season. Subsequently an appropriate sampling procedure minimising...... labour costs and sampling uncertainty is proposed, where the MC of a single stem section with the length of 10–50 cm corresponds to the mean shoot moisture content (MSMC) with a bias of maximum 11 g kg−1. This bias can be reduced by selecting the stem section according to the particular clone...

  13. A critical review of microextraction by packed sorbent as a sample preparation approach in drug bioanalysis.

    Science.gov (United States)

    Alves, Gilberto; Rodrigues, Márcio; Fortuna, Ana; Falcão, Amílcar; Queiroz, João

    2013-06-01

    Sample preparation is widely accepted as the most labor-intensive and error-prone part of the bioanalytical process. The recent advances in this field have been focused on the miniaturization and integration of sample preparation online with analytical instrumentation, in order to reduce laboratory workload and increase analytical performance. From this perspective, microextraction by packed sorbent (MEPS) has emerged in the last few years as a powerful sample preparation approach suitable to be easily automated with liquid and gas chromatographic systems applied in a variety of bioanalytical areas (pharmaceutical, clinical, toxicological, environmental and food research). This paper aims to provide an overview and a critical discussion of recent bioanalytical methods reported in literature based on MEPS, with special emphasis on those developed for the quantification of therapeutic drugs and/or metabolites in biological samples. The advantages and some limitations of MEPS, as well as its comparison with other extraction techniques, are also addressed herein.

  14. Sources of variability in the determination by evaporation method of gross alpha activity in water samples

    Energy Technology Data Exchange (ETDEWEB)

    Baeza, A.; Corbacho, J.A. [LARUEX, Caceres (Spain). Environmental Radioactivity Lab.

    2013-07-01

    Determining the gross alpha activity concentration of water samples is one way to screen for waters whose radionuclide content is so high that its consumption could imply surpassing the Total Indicative Dose as defined in European Directive 98/83/EC. One of the most commonly used methods to prepare the sources to measure gross alpha activity in water samples is desiccation. Its main advantages are the simplicity of the procedure, the low cost of source preparation, and the possibility of simultaneously determining the gross beta activity. The preparation of the source, the construction of the calibration curves, and the measurement procedure itself involve, however, various factors that may introduce sufficient variability into the results to significantly affect the screening process. We here identify the main sources of this variability, and propose specific procedures to follow in the desiccation process that will reduce the uncertainties, and ensure that the result is indeed representative of the sum of the activities of the alpha emitters present in the sample. (orig.)

  15. Use of CTX-I and PINP as bone turnover markers: National Bone Health Alliance recommendations to standardize sample handling and patient preparation to reduce pre-analytical variability.

    Science.gov (United States)

    Szulc, P; Naylor, K; Hoyle, N R; Eastell, R; Leary, E T

    2017-09-01

    The National Bone Health Alliance (NBHA) recommends standardized sample handling and patient preparation for C-terminal telopeptide of type I collagen (CTX-I) and N-terminal propeptide of type I procollagen (PINP) measurements to reduce pre-analytical variability. Controllable and uncontrollable patient-related factors are reviewed to facilitate interpretation and minimize pre-analytical variability. The IOF and the International Federation of Clinical Chemistry (IFCC) Bone Marker Standards Working Group have identified PINP and CTX-I in blood to be the reference markers of bone turnover for the fracture risk prediction and monitoring of osteoporosis treatment. Although used in clinical research for many years, bone turnover markers (BTM) have not been widely adopted in clinical practice primarily due to their poor within-subject and between-lab reproducibility. The NBHA Bone Turnover Marker Project team aim to reduce pre-analytical variability of CTX-I and PINP measurements through standardized sample handling and patient preparation. Recommendations for sample handling and patient preparations were made based on review of available publications and pragmatic considerations to reduce pre-analytical variability. Controllable and un-controllable patient-related factors were reviewed to facilitate interpretation and sample collection. Samples for CTX-I must be collected consistently in the morning hours in the fasted state. EDTA plasma is preferred for CTX-I for its greater sample stability. Sample collection conditions for PINP are less critical as PINP has minimal circadian variability and is not affected by food intake. Sample stability limits should be observed. The uncontrollable aspects (age, sex, pregnancy, immobility, recent fracture, co-morbidities, anti-osteoporotic drugs, other medications) should be considered in BTM interpretation. Adopting standardized sample handling and patient preparation procedures will significantly reduce controllable pre

  16. TEM sample preparation by femtosecond laser machining and ion milling for high-rate TEM straining experiments

    Energy Technology Data Exchange (ETDEWEB)

    Voisin, Thomas; Grapes, Michael D. [Dept. of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218 (United States); Zhang, Yong [Dept. of Mechanical Engineering, Johns Hopkins University, Baltimore, MD 21218 (United States); Lorenzo, Nicholas; Ligda, Jonathan; Schuster, Brian [US Army Research Laboratory, Aberdeen Proving Ground, Aberdeen, MD 21005 (United States); Weihs, Timothy P. [Dept. of Materials Science and Engineering, Johns Hopkins University, Baltimore, MD 21218 (United States)

    2017-04-15

    To model mechanical properties of metals at high strain rates, it is important to visualize and understand their deformation at the nanoscale. Unlike post mortem Transmission Electron Microscopy (TEM), which allows one to analyze defects within samples before or after deformation, in situ TEM is a powerful tool that enables imaging and recording of deformation and the associated defect motion during mechanical loading. Unfortunately, all current in situ TEM mechanical testing techniques are limited to quasi-static strain rates. In this context, we are developing a new test technique that utilizes a rapid straining stage and the Dynamic TEM (DTEM) at the Lawrence Livermore National Laboratory (LLNL). The new straining stage can load samples in tension at strain rates as high as 4×10{sup 3}/s using two piezoelectric actuators operating in bending while the DTEM at LLNL can image in movie mode with a time resolution as short as 70 ns. Given the piezoelectric actuators are limited in force, speed, and displacement, we have developed a method for fabricating TEM samples with small cross-sectional areas to increase the applied stresses and short gage lengths to raise the applied strain rates and to limit the areas of deformation. In this paper, we present our effort to fabricate such samples from bulk materials. The new sample preparation procedure combines femtosecond laser machining and ion milling to obtain 300 µm wide samples with control of both the size and location of the electron transparent area, as well as the gage cross-section and length. - Highlights: • Tensile straining TEM specimens made by femtosecond laser machining and ion milling. • Accurate positioning of the electron transparent area within a controlled gauge region. • Optimization of femtosecond laser and ion milling parameters. • Fast production of numerous samples with a highly repeatable geometry.

  17. Quality Assessment of Platelet-Rich Fibrin-Like Matrix Prepared from Whole Blood Samples after Extended Storage

    Directory of Open Access Journals (Sweden)

    Hideo Kawabata

    2017-09-01

    Full Text Available The platelet-rich fibrin–like matrix (PRFM is usually prepared onsite and immediately used for regenerative therapy. Nonetheless, to meet the clinical necessity of preserving the PRFM without quality deterioration, we developed a method for preparation of PRFMs from short-term-stored whole blood (WB samples. In this study, to evaluate the practical expiration date of storage, we extended the storage time of WB samples from 2 to 7 days and assessed the quality of the resulting PRFMs. WB samples collected with acid-citrate-dextrose were stored with gentle agitation at ambient temperature. To prepare PRFMs, the stored WB samples were mixed with CaCl2 in glass tubes and centrifuged. Fibrin fiber networks, CD41 and CD62P expression, and Platelet Derived Growth Factor-BB (PDGF-BB levels were examined by scanning electron microscopy (SEM, flow cytometry, and an Enzyme-Linked ImmunoSorbent Assay (ELISA, respectively. Long-term storage had no significant effect on either blood cell counts or platelet functions tested. The resulting PRFMs were visually identical to freshly prepared ones. PDGF-BB levels did not markedly decrease in a time-dependent manner. However, fibrin fibers gradually became thinner after storage. Although the coagulation activity may diminish, we propose that PRFMs can be prepared—without evident loss of quality—from WB samples stored for up to 7 days by our previously developed method.

  18. Development of a Novel Self-Enclosed Sample Preparation Device for DNA/RNA Isolation in Space

    Science.gov (United States)

    Zhang, Ye; Mehta, Satish K.; Pensinger, Stuart J.; Pickering, Karen D.

    2011-01-01

    Modern biology techniques present potentials for a wide range of molecular, cellular, and biochemistry applications in space, including detection of infectious pathogens and environmental contaminations, monitoring of drug-resistant microbial and dangerous mutations, identification of new phenotypes of microbial and new life species. However, one of the major technological blockades in enabling these technologies in space is a lack of devices for sample preparation in the space environment. To overcome such an obstacle, we constructed a prototype of a DNA/RNA isolation device based on our novel designs documented in the NASA New Technology Reporting System (MSC-24811-1/3-1). This device is self-enclosed and pipette free, purposely designed for use in the absence of gravity. Our design can also be modified easily for preparing samples in space for other applications, such as flowcytometry, immunostaining, cell separation, sample purification and separation according to its size and charges, sample chemical labeling, and sample purification. The prototype of our DNA/RNA isolation device was tested for efficiencies of DNA and RNA isolation from various cell types for PCR analysis. The purity and integrity of purified DNA and RNA were determined as well. Results showed that our developed DNA/RNA isolation device offers similar efficiency and quality in comparison to the samples prepared using the standard protocol in the laboratory.

  19. Efficacy of a children’s procedural preparation and distraction device on healing in acute burn wound care procedures: study protocol for a randomized controlled trial

    Directory of Open Access Journals (Sweden)

    Brown Nadia J

    2012-12-01

    Full Text Available Abstract Background The intense pain and anxiety triggered by burns and their associated wound care procedures are well established in the literature. Non-pharmacological intervention is a critical component of total pain management protocols and is used as an adjunct to pharmacological analgesia. An example is virtual reality, which has been used effectively to dampen pain intensity and unpleasantness. Possible links or causal relationships between pain/anxiety/stress and burn wound healing have previously not been investigated. The purpose of this study is to investigate these relationships, specifically by determining if a newly developed multi-modal procedural preparation and distraction device (Ditto™ used during acute burn wound care procedures will reduce the pain and anxiety of a child and increase the rate of re-epithelialization. Methods/design Children (4 to 12 years with acute burn injuries presenting for their first dressing change will be randomly assigned to either the (1 Control group (standard distraction or (2 Ditto™ intervention group (receiving Ditto™, procedural preparation and Ditto™ distraction. It is intended that a minimum of 29 participants will be recruited for each treatment group. Repeated measures of pain intensity, anxiety, stress and healing will be taken at every dressing change until complete wound re-epithelialization. Further data collection will aid in determining patient satisfaction and cost effectiveness of the Ditto™ intervention, as well as its effect on speed of wound re-epithelialization. Discussion Results of this study will provide data on whether the disease process can be altered by reducing stress, pain and anxiety in the context of acute burn wounds. Trial registration ACTRN12611000913976

  20. Soil and Water – What is Detectable through Microbiological Sample Preparation Techniques

    Science.gov (United States)

    The concerns of a potential terrorist’s use of biological agents in soil and ground water are articulated by comparisons to major illnesses in this Country involving contaminated drinking water sources. Objectives are focused on the importance of sample preparation in the rapid, ...

  1. Fluoroquinolone antibiotics in environmental waters: sample preparation and determination.

    Science.gov (United States)

    Speltini, Andrea; Sturini, Michela; Maraschi, Federica; Profumo, Antonella

    2010-04-01

    The aim of this review is to provide a general overview on the analytical methods proposed in the last decade for trace fluoroquinolone (FQ) determination in environmental waters. A large number of studies have been developed on this topic in reason of the importance of their monitoring in the studies of environmental mobility and potential degradation pathways. Every step of the analysis has been carefully considered, with a particular attention to sample preparation, in relationship with the problems involved in the analysis of real matrices. The different strategies to minimise interference from organic matter and to achieve optimal sensitivity, especially important in those samples with lower FQ concentrations, were also highlighted. Results and progress in this field have been described and critically commented. Moreover, a worldwide overview on the presence of FQs in the environmental waters has been reported.

  2. Solvent-assisted dispersive solid-phase extraction: A sample preparation method for trace detection of diazinon in urine and environmental water samples.

    Science.gov (United States)

    Aladaghlo, Zolfaghar; Fakhari, Alireza; Behbahani, Mohammad

    2016-09-02

    In this research, a sample preparation method termed solvent-assisted dispersive solid-phase extraction (SA-DSPE) was applied. The used sample preparation method was based on the dispersion of the sorbent into the aqueous sample to maximize the interaction surface. In this approach, the dispersion of the sorbent at a very low milligram level was received by inserting a solution of the sorbent and disperser solvent into the aqueous sample. The cloudy solution created from the dispersion of the sorbent in the bulk aqueous sample. After pre-concentration of the diazinon, the cloudy solution was centrifuged and diazinon in the sediment phase dissolved in ethanol and determined by gas chromatography-flame ionization detector. Under the optimized conditions (pH of solution=7.0, Sorbent: benzophenone, 2%, Disperser solvent: ethanol, 500μL, Centrifuge: centrifuged at 4000rpm for 3min), the method detection limit for diazinon was 0.2, 0.3, 0.3 and 0.3μgL(-1) for distilled water, lake water, waste water and urine sample, respectively. Furthermore, the pre-concentration factor was 363.8, 356.1, 360.7 and 353.38 in distilled water, waste water, lake water and urine sample, respectively. SA-DSPE was successfully used for trace monitoring of diazinon in urine, lake and waste water samples. Copyright © 2016 Elsevier B.V. All rights reserved.

  3. Sample preparation combined with electroanalysis to improve simultaneous determination of antibiotics in animal derived food samples.

    Science.gov (United States)

    da Silva, Wesley Pereira; de Oliveira, Luiz Henrique; Santos, André Luiz Dos; Ferreira, Valdir Souza; Trindade, Magno Aparecido Gonçalves

    2018-06-01

    A procedure based on liquid-liquid extraction (LLE) and phase separation using magnetically stirred salt-induced high-temperature liquid-liquid extraction (PS-MSSI-HT-LLE) was developed to extract and pre-concentrate ciprofloxacin (CIPRO) and enrofloxacin (ENRO) from animal food samples before electroanalysis. Firstly, simple LLE was used to extract the fluoroquinolones (FQs) from animal food samples, in which dilution was performed to reduce interference effects to below a tolerable threshold. Then, adapted PS-MSSI-HT-LLE protocols allowed re-extraction and further pre-concentration of target analytes in the diluted acid samples for simultaneous electrochemical quantification at low concentration levels. To improve the peak separation, in simultaneous detection, a baseline-corrected second-order derivative approach was processed. These approaches allowed quantification of target FQs from animal food samples spiked at levels of 0.80 to 2.00 µmol L -1 in chicken meat, with recovery values always higher than 80.5%, as well as in milk samples spiked at 4.00 µmol L -1 , with recovery values close to 70.0%. Copyright © 2018 Elsevier Ltd. All rights reserved.

  4. Sample Preparation Report of the Fourth OPCW Confidence Building Exercise on Biomedical Sample Analysis

    Energy Technology Data Exchange (ETDEWEB)

    Udey, R. N. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Corzett, T. H. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States); Alcaraz, A. [Lawrence Livermore National Lab. (LLNL), Livermore, CA (United States)

    2014-07-03

    Following the successful completion of the 3rd biomedical confidence building exercise (February 2013 – March 2013), which included the analysis of plasma and urine samples spiked at low ppb levels as part of the exercise scenario, another confidence building exercise was targeted to be conducted in 2014. In this 4th exercise, it was desired to focus specifically on the analysis of plasma samples. The scenario was designed as an investigation of an alleged use of chemical weapons where plasma samples were collected, as plasma has been reported to contain CWA adducts which remain present in the human body for several weeks (Solano et al. 2008). In the 3rd exercise most participants used the fluoride regeneration method to analyze for the presence of nerve agents in plasma samples. For the 4th biomedical exercise it was decided to evaluate the analysis of human plasma samples for the presence/absence of the VX adducts and aged adducts to blood proteins (e.g., VX-butyrylcholinesterase (BuChE) and aged BuChE adducts using a pepsin digest technique to yield nonapeptides; or equivalent). As the aging of VX-BuChE adducts is relatively slow (t1/2 = 77 hr at 37 °C [Aurbek et al. 2009]), soman (GD), which ages much more quickly (t1/2 = 9 min at 37 °C [Masson et al. 2010]), was used to simulate an aged VX sample. Additional objectives of this exercise included having laboratories assess novel OP-adducted plasma sample preparation techniques and analytical instrumentation methodologies, as well as refining/designating the reporting formats for these new techniques.

  5. Experimental procedure for the determination of counting efficiency and sampling flow rate of a grab-sampling working level meter

    International Nuclear Information System (INIS)

    Grenier, M.; Bigu, J.

    1982-07-01

    The calibration procedures used for a working level meter (WLM) of the grab-sampling type are presented in detail. The WLM tested is a Pylon WL-1000C working level meter and it was calibrated for radon/thoron daughter counting efficiency (E), for sampling pump flow rate (Q) and other variables of interest. For the instrument calibrated at the Elliot Lake Laboratory, E was 0.22 +- 0.01 while Q was 4.50 +- 0.01 L/min

  6. The determination of arsenic, selenium, antimony, and tin in complex environmental samples by hydride generation AAS

    International Nuclear Information System (INIS)

    Johnson, D.; Beach, C.

    1990-01-01

    Hydride generation techniques are used routinely for the determination of As, Se, Sb and Sn in water samples. Advantages include high sensitivity, simplicity, and relative freedom from interferences. Continuous-flow designs greatly reduce analysis time as well as improve precision and allow for automation. However the accurate analysis of more complex environmental samples such as industrial sludges, soil samples, river sediments, and fly ash remains difficult. Numerous contributing factors influence the accuracy of the hydride technique. Sample digestion methods and sample preparation procedures are of critical importance. The digestion must adequately solubilize the elements of interest without loss by volatilization. Sample preparation procedures that guarantee the proper analyte oxidation state and eliminate the nitric acid and inter-element interferences are needed. In this study, difficult environmental samples were analyzed for As, Se, Sb, and Sn by continuous flow hydride generation. Sample preparation methods were optimized to eliminate interferences. The results of spike recovery studies will be presented. Data from the analysis of the same samples by graphite furnace AAS will be presented for comparison of accuracy, precision, and analysis time

  7. Rapid Microwave Digestion Procedures for the Elemental Analysis of Alloy and Slag Samples of Smelted Ocean Bed Polymetallic Nodules

    Directory of Open Access Journals (Sweden)

    Kumari Smita

    2013-01-01

    Full Text Available The use of microwave digester for digestion of alloy and slag samples of smelted ocean bed polymetallic nodules has permitted the complete digestion of samples, thereby replacing the tedious classical methods of digestion of samples. The digestion procedure includes two acid-closed digestions of samples in a microwave oven. Owing to the hazardous nature of perchloric acid, it was not used in developed digestion procedure. Digested sample solutions were analyzed for concentrations of various radicals and the effectiveness of the developed digestion methodology was tested using certified reference materials. It was found that the developed method is giving results comparable with that obtained from conventionally digested samples. In this digestion procedure, time required for digestion of samples was reduced to about 1 hour only from 8-9 hours of conventional digestion.

  8. Collected radiochemical and geochemical procedures

    Energy Technology Data Exchange (ETDEWEB)

    Kleinberg, J [comp.

    1990-05-01

    This revision of LA-1721, 4th Ed., Collected Radiochemical Procedures, reflects the activities of two groups in the Isotope and Nuclear Chemistry Division of the Los Alamos National Laboratory: INC-11, Nuclear and radiochemistry; and INC-7, Isotope Geochemistry. The procedures fall into five categories: I. Separation of Radionuclides from Uranium, Fission-Product Solutions, and Nuclear Debris; II. Separation of Products from Irradiated Targets; III. Preparation of Samples for Mass Spectrometric Analysis; IV. Dissolution Procedures; and V. Geochemical Procedures. With one exception, the first category of procedures is ordered by the positions of the elements in the Periodic Table, with separate parts on the Representative Elements (the A groups); the d-Transition Elements (the B groups and the Transition Triads); and the Lanthanides (Rare Earths) and Actinides (the 4f- and 5f-Transition Elements). The members of Group IIIB-- scandium, yttrium, and lanthanum--are included with the lanthanides, elements they resemble closely in chemistry and with which they occur in nature. The procedures dealing with the isolation of products from irradiated targets are arranged by target element.

  9. Recommendations for sampling for prevention of hazards in civil defense. On analytics of chemical, biological and radioactive contaminations. Brief instruction for the CBRN (chemical, biological, radioactive, nuclear) sampling

    International Nuclear Information System (INIS)

    Bachmann, Udo; Biederbick, Walter; Derakshani, Nahid

    2010-01-01

    The recommendation for sampling for prevention of hazards in civil defense is describing the analytics of chemical, biological and radioactive contaminations and includes detail information on the sampling, protocol preparation and documentation procedures. The volume includes a separate brief instruction for the CBRN (chemical, biological, radioactive, nuclear) sampling.

  10. Recent trends in sorption-based sample preparation and liquid chromatography techniques for food analysis.

    Science.gov (United States)

    V Soares Maciel, Edvaldo; de Toffoli, Ana Lúcia; Lanças, Fernando Mauro

    2018-04-20

    The accelerated rising of the world's population increased the consumption of food, thus demanding more rigors in the control of residue and contaminants in food-based products marketed for human consumption. In view of the complexity of most food matrices, including fruits, vegetables, different types of meat, beverages, among others, a sample preparation step is important to provide more reliable results when combined with HPLC separations. An adequate sample preparation step before the chromatographic analysis is mandatory in obtaining higher precision and accuracy in order to improve the extraction of the target analytes, one of the priorities in analytical chemistry. The recent discovery of new materials such as ionic liquids, graphene-derived materials, molecularly imprinted polymers, restricted access media, magnetic nanoparticles, and carbonaceous nanomaterials, provided high sensitivity and selectivity results in an extensive variety of applications. These materials, as well as their several possible combinations, have been demonstrated to be highly appropriate for the extraction of different analytes in complex samples such as food products. The main characteristics and application of these new materials in food analysis will be presented and discussed in this paper. Another topic discussed in this review covers the main advantages and limitations of sample preparation microtechniques, as well as their off-line and on-line combination with HPLC for food analysis. © 2018 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  11. Diagnostic PCR: validation and sample preparation are two sides of the same coin

    DEFF Research Database (Denmark)

    Hoorfar, Jeffrey; Wolffs, Petra; Radstrøm, Peter

    2004-01-01

    Increased use of powerful PCR technology for the routine detection of pathogens has focused attention on the need for international validation and preparation of official non-commercial guidelines. Bacteria of epidemiological importance should be the prime focus, although a "validation...... of quantitative reference DNA material and reagents, production of stringent protocols and tools for thermal cycler performance testing, uncomplicated sample preparation techniques, and extensive ring trials for assessment of the efficacy of selected matrix/pathogen detection protocols....

  12. The Proteome of Ulcerative Colitis in Colon Biopsies from Adults - Optimized Sample Preparation and Comparison with Healthy Controls.

    Science.gov (United States)

    Schniers, Armin; Anderssen, Endre; Fenton, Christopher Graham; Goll, Rasmus; Pasing, Yvonne; Paulssen, Ruth Hracky; Florholmen, Jon; Hansen, Terkel

    2017-12-01

    The purpose of the study was to optimize the sample preparation and to further use an improved sample preparation to identify proteome differences between inflamed ulcerative colitis tissue from untreated adults and healthy controls. To optimize the sample preparation, we studied the effect of adding different detergents to a urea containing lysis buffer for a Lys-C/trypsin tandem digestion. With the optimized method, we prepared clinical samples from six ulcerative colitis patients and six healthy controls and analysed them by LC-MS/MS. We examined the acquired data to identify differences between the states. We improved the protein extraction and protein identification number by utilizing a urea and sodium deoxycholate containing buffer. Comparing ulcerative colitis and healthy tissue, we found 168 of 2366 identified proteins differently abundant. Inflammatory proteins are higher abundant in ulcerative colitis, proteins related to anion-transport and mucus production are lower abundant. A high proportion of S100 proteins is differently abundant, notably with both up-regulated and down-regulated proteins. The optimized sample preparation method will improve future proteomic studies on colon mucosa. The observed protein abundance changes and their enrichment in various groups improve our understanding of ulcerative colitis on protein level. © 2017 WILEY-VCH Verlag GmbH & Co. KGaA, Weinheim.

  13. Sampling design and procedures for fixed surface-water sites in the Georgia-Florida coastal plain study unit, 1993

    Science.gov (United States)

    Hatzell, H.H.; Oaksford, E.T.; Asbury, C.E.

    1995-01-01

    The implementation of design guidelines for the National Water-Quality Assessment (NAWQA) Program has resulted in the development of new sampling procedures and the modification of existing procedures commonly used in the Water Resources Division of the U.S. Geological Survey. The Georgia-Florida Coastal Plain (GAFL) study unit began the intensive data collection phase of the program in October 1992. This report documents the implementation of the NAWQA guidelines by describing the sampling design and procedures for collecting surface-water samples in the GAFL study unit in 1993. This documentation is provided for agencies that use water-quality data and for future study units that will be entering the intensive phase of data collection. The sampling design is intended to account for large- and small-scale spatial variations, and temporal variations in water quality for the study area. Nine fixed sites were selected in drainage basins of different sizes and different land-use characteristics located in different land-resource provinces. Each of the nine fixed sites was sampled regularly for a combination of six constituent groups composed of physical and chemical constituents: field measurements, major ions and metals, nutrients, organic carbon, pesticides, and suspended sediments. Some sites were also sampled during high-flow conditions and storm events. Discussion of the sampling procedure is divided into three phases: sample collection, sample splitting, and sample processing. A cone splitter was used to split water samples for the analysis of the sampling constituent groups except organic carbon from approximately nine liters of stream water collected at four fixed sites that were sampled intensively. An example of the sample splitting schemes designed to provide the sample volumes required for each sample constituent group is described in detail. Information about onsite sample processing has been organized into a flowchart that describes a pathway for each of

  14. The Effect of Sample Preparation and Testing Procedure

    African Journals Online (AJOL)

    School of Civil & Environmental Engineering, Addis Ababa Institute of Technology,. 3. Murray Rix ... the application of laboratory testing and ... clay, tropical red clay, lateritic clay and laterite, ..... grading curves using mass and modified mass.

  15. Direct methylation procedure for converting fatty amides to fatty acid methyl esters in feed and digesta samples.

    Science.gov (United States)

    Jenkins, T C; Thies, E J; Mosley, E E

    2001-05-01

    Two direct methylation procedures often used for the analysis of total fatty acids in biological samples were evaluated for their application to samples containing fatty amides. Methylation of 5 mg of oleamide (cis-9-octadecenamide) in a one-step (methanolic HCl for 2 h at 70 degrees C) or a two-step (sodium methoxide for 10 min at 50 degrees C followed by methanolic HCl for 10 min at 80 degrees C) procedure gave 59 and 16% conversions of oleamide to oleic acid, respectively. Oleic acid recovery from oleamide was increased to 100% when the incubation in methanolic HCl was lengthened to 16 h and increased to 103% when the incubation in methoxide was modified to 24 h at 100 degrees C. However, conversion of oleamide to oleic acid in an animal feed sample was incomplete for the modified (24 h) two-step procedure but complete for the modified (16 h) one-step procedure. Unsaturated fatty amides in feed and digesta samples can be converted to fatty acid methyl esters by incubation in methanolic HCl if the time of exposure to the acid catalyst is extended from 2 to 16 h.

  16. A METHOD FOR PREPARING A SUBSTRATE BY APPLYING A SAMPLE TO BE ANALYSED

    DEFF Research Database (Denmark)

    2017-01-01

    The invention relates to a method for preparing a substrate (105a) comprising a sample reception area (110) and a sensing area (111). The method comprises the steps of: 1) applying a sample on the sample reception area; 2) rotating the substrate around a predetermined axis; 3) during rotation......, at least part of the liquid travels from the sample reception area to the sensing area due to capillary forces acting between the liquid and the substrate; and 4) removing the wave of particles and liquid formed at one end of the substrate. The sensing area is closer to the predetermined axis than...... the sample reception area. The sample comprises a liquid part and particles suspended therein....

  17. Importance of Sample Preparation for Molecular Diagnosis of Lyme Borreliosis from Urine

    OpenAIRE

    Bergmann, A. R.; Schmidt, B. L.; Derler, A.-M.; Aberer, E.

    2002-01-01

    Urine PCR has been used for the diagnosis of Borrelia burgdorferi infection in recent years but has been abandoned because of its low sensitivity and the irreproducibility of the results. Our study aimed to analyze technical details related to sample preparation and detection methods. Crucial for a successful urine PCR were (i) avoidance of the first morning urine sample; (ii) centrifugation at 36,000 × g; and (iii) the extraction method, with only DNAzol of the seven different extraction met...

  18. Preparation and analysis of new proton conducting membranes for fuel cells

    DEFF Research Database (Denmark)

    Søgaard, Susanne Roslev; Huan, Qian; Lund, Peter Brilner

    2007-01-01

    A range of potential new fuel cell membranes were prepared by inserting zirconium phosphate (ZrP) into divinylbenzene (DVB) crosslinked, sulfonated, polystyrene grafted poly(ethylene-alt-tetrafluoroethylene) and poly(vinyl difluoride) membranes using an ion exchange procedure. In short, the prefo......A range of potential new fuel cell membranes were prepared by inserting zirconium phosphate (ZrP) into divinylbenzene (DVB) crosslinked, sulfonated, polystyrene grafted poly(ethylene-alt-tetrafluoroethylene) and poly(vinyl difluoride) membranes using an ion exchange procedure. In short....... Additional zirconium phosphate treatment resulted in composite ETFE samples containing up to 15 wt.% ZrP and composite PVdF samples containing up to 27 wt.%. TG analyses of the ETFE-g-PSSA and PVdF-g-PSSA composite membranes indicated no significant changes of the thermal stability in comparison...

  19. Determination of uranium and thorium isotopes in soil samples by coprecipitation

    International Nuclear Information System (INIS)

    Ngo Quang Huy; Trinh Thi Bich; Nguyen Van Suc

    2012-01-01

    The paper presents a procedure to prepare soil samples for U and Th isotope measurement by alpha-spectrometry after coprecipitation with LaF 3 . In this procedure the reduction of U(VI) to U(IV) was performed by Zn metal in 4M HCl solution. The recoveries of chemical separation equal to ε U-chemistry = 78±4% for uranium and ε Th-chemistry = 82±4% for thorium. Canberra alpha-spectrometer was used with PIPS detectors of A-1200-37-AM Model of 1200 mm 2 active area. The counting efficiency of the measuring system equals to ε counting = 18% and the total efficiencies were ε U = ε counting - ε U-chemistry = 14.0 ± 0.7% for uranium and ε Th = ε counting - ε Th-chemistry = 14.7 ± 0.7% for thorium. The recoveries of chemical separation were rather high (about 80%), that leads to the use of a small weight of soil sample (about 0.5 g). The efficiencies were also stable, that allows analyzing the soil sample without using radiotracers. They are advantages of the sample preparation procedure of this work. (author)

  20. The minimum information required for a glycomics experiment (MIRAGE) project: sample preparation guidelines for reliable reporting of glycomics datasets.

    Science.gov (United States)

    Struwe, Weston B; Agravat, Sanjay; Aoki-Kinoshita, Kiyoko F; Campbell, Matthew P; Costello, Catherine E; Dell, Anne; Ten Feizi; Haslam, Stuart M; Karlsson, Niclas G; Khoo, Kay-Hooi; Kolarich, Daniel; Liu, Yan; McBride, Ryan; Novotny, Milos V; Packer, Nicolle H; Paulson, James C; Rapp, Erdmann; Ranzinger, Rene; Rudd, Pauline M; Smith, David F; Tiemeyer, Michael; Wells, Lance; York, William S; Zaia, Joseph; Kettner, Carsten

    2016-09-01

    The minimum information required for a glycomics experiment (MIRAGE) project was established in 2011 to provide guidelines to aid in data reporting from all types of experiments in glycomics research including mass spectrometry (MS), liquid chromatography, glycan arrays, data handling and sample preparation. MIRAGE is a concerted effort of the wider glycomics community that considers the adaptation of reporting guidelines as an important step towards critical evaluation and dissemination of datasets as well as broadening of experimental techniques worldwide. The MIRAGE Commission published reporting guidelines for MS data and here we outline guidelines for sample preparation. The sample preparation guidelines include all aspects of sample generation, purification and modification from biological and/or synthetic carbohydrate material. The application of MIRAGE sample preparation guidelines will lead to improved recording of experimental protocols and reporting of understandable and reproducible glycomics datasets. © The Author 2016. Published by Oxford University Press. All rights reserved. For permissions, please e-mail: journals.permissions@oup.com.