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The U.S. Food and Drug Administration (FDA) is responsible for the wholesomeness of the nation's food supply. The FDA modified its food monitoring program in January, 1973, to include radioactive isotopes. The methodology used to perform, analyses on these food products are taken from the standerd setting societies such as the AOAC International, American Society for Testing Materials and American Public Health Association Standard Methods. In addition, methods not tested by these societies are taken from the literature or from Department of Energy manuals such as the Health and Safety Laboratory and also from Environmental Protection Agency, Public Health Service, and Food and Agricultural Organization manuals. These include the methods for long-lived radionuclides such as tritium, strontium-90, cesium-137 and plutonium. Also, the short-lived radionuclides such as iodine-131, radiocesium, radiocerium and radioruthenium. In addition, they include the natural occurring radionuclides such as radium and uranium isotopes. The activity concentrations of gamma-emitters such as radiocesium, iodine-131 and radioruthenium are determined by gamma-ray spectrometry. This is done using intrinsic germanium detectors with the appropriate hardware and software. The alpha and “pure” beta-emitters are determined by various radiochemical methods and techniques. The radiochemical methodology and equipment used in analyzing these radionuclides are described and discussed. Also, the methodology and equipment for the gamma-emitters are described in more detail in this paper. In addition, the limits of detection for the methods used will be discussed.  相似文献   

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The Centre for Nuclear Sciences was established in 1984 with the mandate to introduce Caribbean scientists to the application of nuclear technology in multi-disciplinary studies, and to carry out research in areas of national and regional importance. This paper describes the pesent facilities and the major programmes being carried out at the Centre.  相似文献   

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Foods are complex mixtures of lipids, carbohydrates, proteins, vitamins, organic compounds, and other naturally occurring substances. Sometimes added to this mixture are residues of pesticides, veterinary and human drugs, microbial toxins, preservatives, contaminants from food processing and packaging, and other residues. This milieu of compounds can pose difficulties in the analysis of food contaminants. There is an expanding need for rapid and cost-effective residue methods for difficult food matrixes to safeguard our food supply. Bioanalytical methods are established for many food contaminants such as mycotoxins and are the method of choice for many food allergens. Bioanalytical methods are often more cost-effective and sensitive than instrumental procedures. Recent developments in bioanalytical methods may provide more applications for their use in food analysis.  相似文献   

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One of the most critical factors in developing pharmaceutical drug substances and drug products today is ensuring that the HPLC analytical test methods that are used to analyze the products generate meaningful data. The US Food and Drug Administration (FDA) and United States Pharmacopeia (USP) have each recognized the importance of this to the drug development process and have separately increased validation requirements in recent years. A third source, the International Conference on Harmonization (ICH), has added requirements that, when combined with the previous two sources, have led to three different sets of validation requirements leaving the industry in a state of confusion. This paper is written to clear up the confusion over the validation requirements that are presented by each of these three sources.  相似文献   

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A series of potent heterocyclic amines that are mutagenic and carcinogenic have been discovered that are formed in some heated foods, most notably, meats derived from muscle. Determining the heterocyclic amine content in foods and food products is required for toxicological research, industry quality control, and possibly in the future, regulatory control. The contents of food needs to be determined using reliable analytical techniques. Since heterocyclic amines are present in foods at ng/g levels, a variety of liquid-liquid or solid-phase purification techniques are required, followed by gas or high-performance liquid chromatography. Peak detection has been successful using UV, fluorescence, and mass spectrometric detection, and biological activity using the Ames/Salmonella test. The low levels present require that chromatographic efficiency, and both detector sensitivity and selectivity be optimized. The cartridge solid-phase extraction and high-performance liquid chromatography method have been used to measure the known food-derived heterocyclic amines for several types of food, and to the authors knowledge, this is the only method undergoing intralaboratory comparison and validation. Our analysis of the literature shows that chromatographic analysis of the heterocyclic amines by high-performance liquid chromatography or gas chromatography (with derivatization) is satisfactory for heterocyclic amine analysis in foods although the methods are just now being optimized for routine use. The biggest improvements in speed and accuracy will probably come from improved extraction methods as analysis of complex food samples for heterocyclic amines will always be a challenge.  相似文献   

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For more than 50 years, nuclear methods have been applied to chemical analysis at the National Institute of Standards and Technology. Radiochemical, instrumental, and prompt-gamma activation analysis are used, as well as neutron depth profiling and other techniques. The history of this group in methods development and the certification of Standard Reference Materials, among other applications, is reviewed.  相似文献   

8.
Recent advances in capillary electrophoresis methods for food analysis   总被引:2,自引:0,他引:2  
Frazier RA 《Electrophoresis》2001,22(19):4197-4206
This review article addresses recent advances in the analysis of foods and food components by capillary electrophoresis (CE). CE has found application to a number of important areas of food analysis, including quantitative chemical analysis of food additives, biochemical analysis of protein composition, and others. The speed, resolution and simplicity of CE, combined with low operating costs, make the technique an attractive option for the development of improved methods of food analysis for the new millennium.  相似文献   

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The use of the multidimensional detection systems, mass spectrometry and NMR, with separation techniques is discussed with a consideration of their actual or potential application in food analysis. The features of the most commonly used interfaces for coupling liquid chromatography (LC) and mass spectrometry (MS) are briefly examined and examples from the literature on the use of LC-MS in the analysis of natural components in foodstuffs are reported. The potential capabilities for food analysis of LC-NMR, supercritical fluid chromatography (SFC)-MS and capillary electrophoresis (CE)-MS are highlighted.  相似文献   

11.
Frazier RA  Ames JM  Nursten HE 《Electrophoresis》1999,20(15-16):3156-3180
Capillary electrophoresis (CE) offers the analyst a number of key advantages for the analysis of the components of foods. CE offers better resolution than, say, high-performance liquid chromatography (HPLC), and is more adept at the simultaneous separation of a number of components of different chemistries within a single matrix. In addition, CE requires less rigorous sample cleanup procedures than HPLC, while offering the same degree of automation. However, despite these advantages, CE remains under-utilized by food analysts. Therefore, this review consolidates and discusses the currently reported applications of CE that are relevant to the analysis of foods. Some discussion is also devoted to the development of these reported methods and to the advantages/disadvantages compared with the more usual methods for each particular analysis. It is the aim of this review to give practicing food analysts an overview of the current scope of CE.  相似文献   

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The first U.S. court case involving forensic activation analysis (FAA) took place in March of 1964. During the subsequent five years, many other cases involving FAA results went to trial in the U.S., but these seldom involved any serious attempts by the defense to challenge the FAA testimony presented by the prosecution. During roughly the last three years, however, there have been a number of U.S. court cases in which activation analysis have appeared in court as expert witnesses-one or more for the prosecution and one or more for the defense, in opposition to one another. Some of these recent cases have been most interesting and significant-and they reveal some of the shortcomings and special problems of the present status of FAA, not from the standpoint of its use in the investigative stages of criminal cases, but rather from the standpoint of the proper presentation and interpretation of such results in court. The author has participated in some of the cases to be cited, either as an expert witness for the prosecution or for the defense, and has had close contact with the details of some of the other cases to be cited. Some hopefully useful conclusions have been drawn from studies of these cases, and these conclusions will be presented, along with some of the relevant details of the cases.  相似文献   

14.
This article reviews the latest developments in the application of capillary electromigration methods for the analysis of foods and food components. Nowadays, methods based on CE techniques are becoming widely used in food analytical and research laboratories. This review covers the application of CE to analyze amino acids, biogenic amines, peptides, proteins, DNAs, carbohydrates, phenols, polyphenols, pigments, toxins, pesticides, vitamins, additives, small organic and inorganic ions, chiral compounds, and other compounds in foods, as well as to investigate food interactions and food processing. The use of microchips as well as other foreseen trends in CE analysis of foods is discussed. Papers that were published during the period June 2002-June 2005 are included following the previous review by Frazier and Papadopoulou (Electrophoresis 2003, 24, 4095-4105).  相似文献   

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This review covers the application of capillary electromigration methods to analyze foods and food components, including amino acids, biogenic amines, peptides, proteins, DNAs, carbohydrates, phenols, polyphenols, pigments, toxins, pesticides, vitamins, additives, small organic and inorganic ions, chiral compounds, and other compounds in foods, as well as those applications of CE for monitoring food interactions and food processing. The use of microchips as well as other foreseen trends in food analysis by CE are discussed. Papers that were published during the period June 2005-March 2007 are included following the previous review by Cifuentes (Electrophoresis 2006, 27, 283-303).  相似文献   

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This article describes the trends in analytical techniques for the determination of trichothecene mycotoxins, namely deoxynivalenol, and T-2 and HT-2 toxins in cereals and cereal products with particular emphasis on screening and rapid approaches. The driving force behind the changing methodologies is mainly attributed to legislative demands. However, for commercial and governmental testing laboratories, the need to use validated official methods is ever increasing to ensure quality assurance of results.Much research has been undertaken to improve screening assays, highlighted by the number of new methods using a variety of formats and platforms, including optical and electrochemical biosensors. Significant advances in the traditional reference methods have also been demonstrated in addition to the emergence of a variety of commercial immunoaffinity and solid-phase extraction columns for clean up. The use of liquid chromatography coupled to tandem mass spectrometry for mycotoxin detection is ever increasing, allowing simultaneous determination of many toxins in various sample matrices.  相似文献   

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An overview of the nuclear analytical methods oppurtunities at the University of Illinois at Urbana-Champaign is given. Undergraduate and graduate level teaching and research are highlighted. The TRIGA reactor and neutron activation analysis facilities are described in the context of this role within an inter-disciplinary environment.  相似文献   

18.
The analysis of food components using capillary electromigration methods is reviewed in this work. Papers that were published from February 2009 to February 2011 are included following the previous review by Herrero et al. (Electrophoresis, 2010, 31, 205-228). The analysis of amino acids, biogenic amines, peptides, proteins, DNAs, carbohydrates, phenols, polyphenols, pigments, toxins, pesticides, vitamins, additives, small organic and inorganic ions and other compounds found in foods and beverages are reviewed, as well as those applications of CE for monitoring food interactions and food processing. The use of microchips, CE-MS and chiral-CE in food analysis is also discussed as well as other current and foreseen trends in this area of research including new developments in Foodomics.  相似文献   

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Analytical Chemistry is taught at over 600 schools of higher education in the U.S.S.R. Contents of general and special courses are described in this article. The main problems and objectives of education at universities are mentioned.  相似文献   

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