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1.
Biochem Soc Trans ; 48(6): 2457-2466, 2020 12 18.
Artigo em Inglês | MEDLINE | ID: mdl-33336686

RESUMO

Ion Mobility (IM) coupled to mass spectrometry (MS) is a useful tool for separating species of interest out of small quantities of heterogenous mixtures via a combination of m/z and molecular shape. While tandem MS instruments are common, instruments which employ tandem IM are less so with the first commercial IM-MS instrument capable of multiple IM selection rounds being released in 2019. Here we explore the history of tandem IM instruments, recent developments, the applications to biological systems and expected future directions.


Assuntos
Espectrometria de Mobilidade Iônica/instrumentação , Espectrometria de Mobilidade Iônica/métodos , Espectrometria de Massas em Tandem/instrumentação , Espectrometria de Massas em Tandem/métodos , Biofísica/história , Biofísica/tendências , Técnicas de Química Analítica/história , Técnicas de Química Analítica/tendências , Desenho de Equipamento , História do Século XX , História do Século XXI , Espectrometria de Mobilidade Iônica/tendências , Íons , Espectrometria de Massas em Tandem/tendências
2.
Spectrochim Acta A Mol Biomol Spectrosc ; 228: 117817, 2020 Mar 05.
Artigo em Inglês | MEDLINE | ID: mdl-31780310

RESUMO

Fluoride ion (F-) contamination can be accumulated along the water and the food chain and cause serious risk to public health. It is of the greatest importance that selects the suitable chromophores and fluorophores for the design and synthesis of outstanding selective, sensitive chromogenic and fluorogenic probes for detection of fluoride ion. In this review is mainly focused on the current progress of fluoride ion detection according to their receptors into several categories like anthracene, azo, benzothiazole, BODIPY, calixarene, coumarin, imidazole, diketopyrrolopyrrole, hydrazone, imidazole, naphthalene, naphthalimide, quantum dots, Schiff base and urea group sensing in the year 2015-2019.


Assuntos
Colorimetria/instrumentação , Fluoretos/análise , Íons/química , Compostos de Boro/química , Técnicas de Química Analítica/história , Colorimetria/métodos , Cumarínicos/química , Elétrons , Transferência Ressonante de Energia de Fluorescência , Corantes Fluorescentes/química , Flúor , História do Século XXI , Hidrazonas/química , Ligação de Hidrogênio , Fotoquímica/métodos , Pontos Quânticos/química , Bases de Schiff/química , Espectrometria de Fluorescência
5.
Ann Sci ; 72(4): 490-516, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-26221836

RESUMO

This paper analyses the development of three methods for detecting bloodstains during the first half of the nineteenth-century in France. After dealing with the main problems in detecting bloodstains, the paper describes the chemical tests introduced in the mid-1820s. Then the first uses of the microscope in the detection of bloodstains around 1827 are discussed. The most controversial method is then examined, the smell test introduced by Jean-Pierre Barruel in 1829, and the debates which took place in French academies and learned societies during ensuing years are surveyed. Moving to the courtrooms a review is conducted of how the different methods were employed in criminal trials. By reviewing these cases, the main arguments against Barruel's test during the 1830s are explored as well as the changes making possible the return of the microscope to legal medicine around 1840. By reconstructing the history of these three methods, the paper reveals how the senses of smell and vision (colours and microscopic images) were employed in order to produce convincing evidence in both academies and courts. The paper questions two linear master narratives that are organized in terms of progress and decline: the development of forensic science as a result of continued technological progress; and the supposed decline of smell in the history of the senses, particularly in the realm of chemistry and medicine.


Assuntos
Manchas de Sangue , Técnicas de Química Analítica/história , Medicina Legal/história , Microscopia/história , Odorantes/análise , Técnicas de Química Analítica/métodos , Medicina Legal/métodos , França , História do Século XIX , Humanos , Microscopia/métodos
6.
Anal Chem ; 87(9): 4588-96, 2015.
Artigo em Inglês | MEDLINE | ID: mdl-25745805

RESUMO

In this Feature we use automatic bibliometric mapping tools to visualize the history of analytical chemistry from the 1920s until the present. In particular, we have focused on the application of mass spectrometry in different fields. The analysis shows major shifts in research focus and use of mass spectrometry. We conclude by discussing the application of bibliometric mapping and visualization tools in analytical chemists' research.


Assuntos
Bibliometria , Técnicas de Química Analítica/história , Espectrometria de Massas/história , Técnicas de Química Analítica/tendências , História do Século XX , História do Século XXI , Espectrometria de Massas/tendências , Pesquisa/história , Pesquisa/tendências
7.
Ambix ; 61(3): 279-98, 2014 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-25276875

RESUMO

This article centres on a particularly intense debate within British analytical chemistry in the late nineteenth century, between local public analysts and the government chemists of the Inland Revenue Service. The two groups differed in both practical methodologies and in the interpretation of analytical findings. The most striking debates in this period were related to milk analysis, highlighted especially in Victorian courtrooms. It was in protracted court cases, such as the well known Manchester Milk Case in 1883, that analytical chemistry was performed between local public analysts and the government chemists, who were often both used as expert witnesses. Victorian courtrooms were thus important sites in the context of the uneven professionalisation of chemistry. I use this tension to highlight what Christopher Hamlin has called the defining feature of Victorian public health, namely conflicts of professional jurisdiction, which adds nuance to histories of the struggle of professionalisation and public credibility in analytical chemistry.


Assuntos
Técnicas de Química Analítica/história , Química Analítica/história , Contaminação de Alimentos , Leite/história , Animais , Técnicas de Química Analítica/métodos , Química Analítica/legislação & jurisprudência , Conflito de Interesses , Contaminação de Alimentos/análise , Contaminação de Alimentos/legislação & jurisprudência , História do Século XIX , Leite/química , Reino Unido
10.
Bioanalysis ; 5(16): 1949-52, 2013 Aug.
Artigo em Inglês | MEDLINE | ID: mdl-23937128

RESUMO

Irving W Wainer, Senior Investigator in the Intramural Research Program at the National Institute on Aging/NIH received his PhD degree in chemistry from Cornell University and did postdoctoral doctoral studies in molecular biology (University of Oregon) and clinical pharmacology (Thomas Jefferson Medical School). He worked for the US FDA and held positions at St Jude's Children's Research Hospital, at McGill University as Professor in the Department of Oncology, and as a Professor of Pharmacology at Georgetown University. Wainer has published over 350 scientific papers, 10 books, 25 book chapters and holds 11 patents. His awards include: 'A.J.P. Martin Medal' presented by the Chromatographic Society; Doctor HonorisCausa awarded by the Medical University of Gdansk (Gdansk, Poland, 2006), Doctor HonorisCausa awarded by the Department of Medicine, University of Liege (Liege, Belgium, 2012), and the 2013 Eastern Analytical Symposium Award for Outstanding Contributions to the Fields of Analytical Chemistry. Wainer's research includes the development of new therapeutic agents for the treatment of congestive heart failure, cancer, pain and depression, many of which are in the later stages of drug development. His laboratory has also continued the development of cellular membrane affinity chromatography technology, and recent work includes the development of columns containing immobilized forms of the breast cancer resistance protein found in cellular and nuclear membranes and mitochondrial membrane columns. Wainer's laboratory has also continued its study of the effect of disease progression and aging on drug metabolism in critically ill and terminal patients. Interview was conducted by Lisa Parks, Assistant Commissioning Editor of Bioanalysis.


Assuntos
Bioensaio/história , Técnicas de Química Analítica/história , Cromatografia/história , Fracionamento Químico/métodos , História do Século XX , História do Século XXI , Preparações Farmacêuticas/química , Preparações Farmacêuticas/história , Farmacologia Clínica/história
13.
Rep Prog Phys ; 76(1): 016101, 2013 Jan.
Artigo em Inglês | MEDLINE | ID: mdl-23249618

RESUMO

The measurement of the Planck constant, h, is entering a new phase. The CODATA 2010 recommended value is 6.626 069 57 × 10(-34) J s, but it has been a long road, and the trip is not over yet. Since its discovery as a fundamental physical constant to explain various effects in quantum theory, h has become especially important in defining standards for electrical measurements and soon, for mass determination. Measuring h in the International System of Units (SI) started as experimental attempts merely to prove its existence. Many decades passed while newer experiments measured physical effects that were the influence of h combined with other physical constants: elementary charge, e, and the Avogadro constant, N(A). As experimental techniques improved, the precision of the value of h expanded. When the Josephson and quantum Hall theories led to new electronic devices, and a hundred year old experiment, the absolute ampere, was altered into a watt balance, h not only became vital in definitions for the volt and ohm units, but suddenly it could be measured directly and even more accurately. Finally, as measurement uncertainties now approach a few parts in 10(8) from the watt balance experiments and Avogadro determinations, its importance has been linked to a proposed redefinition of a kilogram unit of mass. The path to higher accuracy in measuring the value of h was not always an example of continuous progress. Since new measurements periodically led to changes in its accepted value and the corresponding SI units, it is helpful to see why there were bumps in the road and where the different branch lines of research joined in the effort. Recalling the bumps along this road will hopefully avoid their repetition in the upcoming SI redefinition debates. This paper begins with a brief history of the methods to measure a combination of fundamental constants, thus indirectly obtaining the Planck constant. The historical path is followed in the section describing how the improved techniques and discoveries in quantum mechanics steadily reduced the uncertainty of h. The central part of this review describes the technical details of the watt balance technique, which is a combination of the mechanical and electronic measurements that now determine h as a direct result, i.e. not requiring measured values of additional fundamental constants. The first technical section describes the basics and some of the common details of many watt balance designs. Next is a review of the ongoing advances at the (currently) seven national metrology institutions where these experiments are pursued. A final summary of the recent h determinations of the last two decades shows how history keeps repeating itself; there is again a question of whether there is a shift in the newest results, albeit at uncertainties that are many orders of magnitude less than the original experiments. The conclusion is that there is room for further development to resolve these differences and find new ideas for a watt balance system with a more universal application. Since the next generation of watt balance experiments are expected to become kilogram realization standards, the historical record suggests that there is yet a need for proof that Planck constant results are finally reproducible at an acceptable uncertainty.


Assuntos
Técnicas de Química Analítica/história , Física/história , Física/tendências , Teoria Quântica/história , Termodinâmica , História do Século XX , História do Século XXI
14.
Talanta ; 102: 16-25, 2012 Dec 15.
Artigo em Inglês | MEDLINE | ID: mdl-23182570

RESUMO

In this tutorial review we give a concise and general overview of the development of imaging analytical techniques from its early stages in the late 1950s up to the present. Analytical techniques that are available for the characterization of the atomic and molecular composition as well as the structure at the bulk level often fail for the analysis of heterogeneous materials. Over the last 50 years a number of specialized analytical techniques were developed - or adapted from existing techniques - that, with time, matured into powerful tools for visualizing structural and compositional heterogeneity in nanotechnology and for the study of natural objects. These techniques evolved first at the microscopic and then the mesoscopic level (the range 100-1,000 nm), and later onto the nanoscopic scale between a few nm and 100 nm, where quantum effects start affecting the properties of materials.


Assuntos
Técnicas de Química Analítica/história , Diagnóstico por Imagem/história , História do Século XIX , História do Século XX , História do Século XXI
15.
Ambix ; 59(2): 109-30, 2012 Jul.
Artigo em Inglês | MEDLINE | ID: mdl-23057184

RESUMO

In 1962, Rachel Carson's Silent Spring drew the public's attention to the deleterious effects of chlorinated hydrocarbons employed as economic poisons in agriculture. However, she did not discuss how their residues could be routinely identified and quantified. In part, this was because the introduction of instruments for use in environmental analysis had only just begun, and she was probably unaware of their existence. The development of the instrumental methods began in industry, particularly at Dow and Shell, in the mid-1950s. Dow scientists, by combining mass spectrometry with gas chromatography, developed the most powerful technique, then and now, for the separation, quantitation and identification of chlorinated hydrocarbons. Shell scientists were no less innovative, particularly with the application of highly sensitive gas chromatography detectors to trace analysis. The first of these detectors, the electron capture detector, was invented by James Lovelock at the National Institute of Medical Research, North London, at the end of the 1950s. Around the same time, Dale Coulson in the USA developed his microcoulometric detector.


Assuntos
Técnicas de Química Analítica/história , Hidrocarbonetos Clorados/história , Resíduos de Praguicidas/história , Técnicas de Química Analítica/instrumentação , Técnicas de Química Analítica/métodos , Cromatografia Gasosa/história , Cromatografia Gasosa/instrumentação , Cromatografia Gasosa/métodos , História do Século XX , Hidrocarbonetos Clorados/análise , Hidrocarbonetos Clorados/toxicidade , Espectrometria de Massas/história , Espectrometria de Massas/instrumentação , Espectrometria de Massas/métodos , Resíduos de Praguicidas/análise , Resíduos de Praguicidas/toxicidade , Reino Unido , Estados Unidos
16.
Kwart Hist Nauki Tech ; 57(1): 9-21, 2012.
Artigo em Polonês | MEDLINE | ID: mdl-22849241

RESUMO

Maria Sklodowska-Curie--a Nobel Prize winner in chemistry--the elements of learning of chemistry gained just by a dint of work of more than ten months in Warsaw in the Institute of Industry and Agriculture Museum. The Nobel Prize concerned a contribution to the progress of chemistry through the discovery of radium and polonium, separation of radium and study of properties of this amazing element. It was awarded for an extremely arduous work, during which the chemical reactions being the principles of analytical chemistry were realized. Unlike to a typical analytical procedure, an initial attempt here was the thousands of kilograms of uranium ore: pitchblende. The final effect was small amounts of new elements: polonium and radium. Both the knowledge and the intuition of the researcher let her have a triumph. The difficulties she experienced because the properties of the searched chemical elements could only be evaluated thanks to the knowledge on other chemical elements. A significant achievement was the determination of the samples by means of radioactivity measurement, which gave rise to radiochemical analytical methods. An extreme analytical precision was demanded in multiple processes of fractional crystallization and precipitation which finally led to the calculation of the atomic mass of radium.


Assuntos
Técnicas de Química Analítica/história , Química Analítica/história , Prêmio Nobel , Academias e Institutos/história , Feminino , França , História do Século XIX , História do Século XX , Humanos , Polônia , Polônio/história , Rádio (Elemento)/história , Pesquisadores/história
17.
J AOAC Int ; 94(2): 360-72, 2011.
Artigo em Inglês | MEDLINE | ID: mdl-21563669

RESUMO

In this paper, the past, present, and (possible) future of the European analytical criteria for residues are described. The elaboration of the revision of Commission Decision 9312561EC was a long process starting in 1996 and ending with the formation of a European Commission (EC) working group in 1998. This working group took account of developments in scientific and technical knowledge at that time and produced a draft version of the revision within 6 months. The revision, finally published in 2002 (2002/657/EC), includes new ideas on the identification of analytes and the criteria for performance assessment as well as validation procedures. Currently (2009), the evolution in analytical equipment and progress in scientific research, accompanied by recent European regulatory changes, demands an update or revision of the 2002/657/EC.


Assuntos
Anabolizantes/química , Técnicas de Química Analítica/normas , Técnicas de Química Analítica/tendências , Resíduos de Drogas/química , Poluentes Ambientais/química , Drogas Veterinárias/química , Técnicas de Química Analítica/história , Europa (Continente) , História do Século XX , História do Século XXI
18.
Ter Arkh ; 83(11): 76-80, 2011.
Artigo em Russo | MEDLINE | ID: mdl-22312892

RESUMO

The article concerns the end stage of clinical medicine establishment covering the period from early 1840s to the middle 1870s of the XIX century. Basic scientific achievements related to introduction into practical medicine of the methods of laboratory experiment and chemical analysis are reviewed.


Assuntos
Técnicas de Química Analítica/história , Técnicas de Laboratório Clínico/história , Medicina Clínica/história , História do Século XIX , Humanos
19.
Artigo em Inglês | MEDLINE | ID: mdl-20948176

RESUMO

My career has been focused in two major areas, analytical chemistry and biochemistry of complex lipids and glycoconjugates. Included here are the pioneering work on the gas chromatography of long-chain sphingolipid bases, carbohydrates, steroids and urinary organic acids. Mass spectrometry was utilized extensively in structural studies of sphingolipids, fatty acids, carbohydrates, steroids, urinary organic acids, polyisoprenoid alcohols, and juvenile hormone. Computer systems were developed for the acquisition and analysis of mass spectra, and were used for development of automated metabolic profiling of complex mixtures of metabolites. Fabry's disease was discovered to be a glycosphingolipidosis. Enzymes of lysosomal metabolism of glycosphingolipids were purified, characterized, and used in one of the first demonstrations of the feasibility of enzyme replacement therapy in a lysosomal storage disorder (Fabry's disease). Extracellular sialidases were studied to evaluate the hypothesis that they might be involved in the regulation of membrane growth factor receptors. The enzyme for hematoside synthesis was purified and characterized.


Assuntos
Bioquímica/história , Técnicas de Química Analítica/história , Animais , Automação , Cães , Glicoconjugados/química , Glicoesfingolipídeos/química , História do Século XX , Humanos , Insetos , Lipídeos/química , Lisossomos/metabolismo , Espectrometria de Massas/métodos , Modelos Químicos , Neuraminidase/química , Ratos
20.
J Agric Food Chem ; 57(18): 8115-24, 2009 Sep 23.
Artigo em Inglês | MEDLINE | ID: mdl-19719125

RESUMO

Citrus juices are a complex mixture of flavor and taste components. Historically, the contributions of taste components such as sugar (sweet) and acid (sour) components were understood before impactful aroma volatiles because they existed at higher concentrations and could be measured with the technologies of the 1920s and 1930s. The advent of gas chromatography in the 1950s allowed citrus researchers to separate and tentatively identify the major citrus volatiles. Additional volatiles were identified when mass spectrometry was coupled to capillary GC. Unfortunately, the major citrus volatiles were not major influences of citrus flavor. The major aroma impact compounds were found at trace concentrations. With the advent of increasingly more sensitive instrumental techniques, juice sample size shrank from 2025 L in the 1920s to 10 mL today and detection limits fell from percent to micrograms per liter. Currently gas chromatography-olfactometry is the technique of choice to identify which volatiles in citrus juices possess aroma activity, determine their relative aroma strength, and characterize their aroma quality but does not indicate how they interact together or with the juice matrix. Flavor equations based primarily on nonvolatiles and other physical measurements have been largely unsuccessful. The most successful flavor prediction equations that employ instrumental concentration values are based on a combination of aroma active volatiles and degrees Brix (sugar) values.


Assuntos
Citrus/química , Tecnologia de Alimentos/história , Frutas/química , Paladar , Bebidas/análise , Técnicas de Química Analítica/história , Cromatografia Gasosa , Citrus paradisi/química , Citrus sinensis/química , Manipulação de Alimentos/história , Manipulação de Alimentos/métodos , Tecnologia de Alimentos/métodos , História do Século XX , História do Século XXI , Humanos , Odorantes/análise , Olfato , Compostos Orgânicos Voláteis/análise
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