PubMed Health⌕ Search

SEARCH · PubMed Health

Results for “Chemistry, Analytic”

Explore indexed PubMed citations for clinical trials, systematic reviews and public health research. Read source abstracts and follow each citation to its original PubMed record.

Quote a phrase for an exact phrase match. Source license links do not imply unrestricted reuse.

At least 19 recordsLinked to original sources
PubMed1984

Effects of scientific advances on the decision-making process: analytical chemistry.

The analytical chemist has taken the science of identification and quantitation of chemical compounds far beyond the capability of the toxicologist to correlate with the results of animal experiments. In pursuing the vanishing zero, however, the analytical chemist has failed to acknowledge the inherent variability of chemical measurements at very low concentrations that manifest itself not only as discrepant values but as an appreciable fraction of false positive and false negative results and as real negative values (the blank or control is greater than the determination). These are the symptoms of a system not in statistical control. The same type of variable results, evident in biological systems as "biological variability," are then manipulated by statisticians as if they were reproducible measurements. Progress in characterizing biological uncertainty cannot be made until the invisible systematic error of individual laboratories is transformed into random error, amenable to the application of statistical principles. In measurement theory, an examination and correction of systematic error requires knowledge or assignment of a "true value," a concept that does not appear to exist in many biological systems.

Animals↗
PubMed1989

A review of the application of chiroptical methods to analytical chemistry.

The analytical applications of the two most important chiroptical methods, optical rotatory dispersions (ORD) and circular dichroism (CD), have been surveyed, emphasizing the methods corresponding to the profile of the Journal of Pharmaceutical and Biomedical Analysis. After a brief introduction of the ORD and CD methods, the advantages and drawbacks of the application of the two methods have been described, and compared, and the calibration of ORD and CD instruments have been given. The analytical applications have been divided as follows: the use of ORD and CD in identification studies, the direct determination of optically active substances, the determination of optically active compounds after chromophore group formation, determination of optically inactive substances via their products with optically active compounds. The difference chiroptical methods increasing the selectivity of measurements and the chiroptical titrations have been summarized. Stress has been laid on the applicability of selective chiroptical detectors (based on laser light, too) used in liquid chromatography and the future developments have been mentioned.

Circular Dichroism↗
PubMedDate not supplied

Progress in forensic toxicology: beyond analytical chemistry.

The dominant role of analytical chemistry in applied forensic toxicology is described briefly from an historical perspective. It is argued, however, that obligations imposed on forensic toxicologists by the law, medicine, and society for understanding toxicity in an increasing variety of case problems is really the major challenge and obligation facing toxicologists today. Case examples and rationale are presented in support of this argument. Needs and possible solutions to redress the current professional imbalance are suggested; such as a program to monitor prospectively adverse drug actions and interactions, forensic toxicology reference centers, graduate training programs, and collaborative research involving analytical toxicologists and biomedical researchers, including pathologists. There is a need to develop an industrial, governmental, and professional partnership. These proposals are discussed and justified.

Chemistry Techniques, Analytical↗
PubMed1989

Chromatography beyond analytical chemistry.

Although chromatography is one of the most important branches of analytical chemistry, it also serves purposes that cannot strictly be considered as part of analytical chemistry: it may be a model of natural processes, a method for the study of surface properties of molecules, for the collection of data in quantitative structure-activity relationship studies and for preparative separations, a teaching aid and sometimes even a kind of visual art. Some speculations and proposals are summarized.

Chemistry Techniques, Analytical↗
PubMed1985

Research in the Division of Analytical Chemistry.

Within the Center for Bio-Pharmaceutical Sciences, the Division of Analytical Chemistry develops the tools that are used in other divisions. The numerous techniques of analytical chemistry are studied in order to improve selectivity, sensitivity, etc. The emphasis of the research is on bioanalysis. The possibilities and pitfalls of bioanalysis are demonstrated with vitamin KI (phylloquinone), where a detection limit of 5 pg can be reached.

Academies and Institutes↗
PubMed1984

Analytical chemistry of nickel.

Analytical chemists are faced with nickel contents in environmental and biological materials ranging from the mg/kg down to the ng/kg level. Sampling and sample treatment have to be performed with great care at lower levels, and this also applies to enrichment and separation procedures. The classical determination methods formerly used have been replaced almost entirely by different forms of atomic absorption spectrometry. Electroanalytical methods are also of increasing importance and at present provide the most sensitive approach. Despite the powerful methods available, achieving reliable results is still a challenge for the analyst requiring proper quality control measures.

Beverages↗
PubMed1986

Pattern recognition used to investigate multivariate data in analytical chemistry.

Pattern recognition and allied multivariate methods provide an approach to the interpretation of the multivariate data often encountered in analytical chemistry. Widely used methods include mapping and display, discriminant development, clustering, and modeling. Each has been applied to a variety of chemical problems, and examples are given. The results of two recent studies are shown, a classification of subjects as normal or cystic fibrosis heterozygotes and simulation of chemical shifts of carbon-13 nuclear magnetic resonance spectra by linear model equations.

Carbon Radioisotopes↗
PubMed1986

Immunoassays in environmental analytical chemistry.

A review is presented which summarizes the recent developments of immunoassays in environmental analytical chemistry. The basic principle of the method and the following steps in the development of an immunoassay procedure are discussed in detail: Synthesis of the immunogen, immunization procedure, synthesis of the labelled antigen (tracer), advantages and drawbacks of radioimmunoassay, fluoroimmunoassay and enzyme immunoassay. A special emphasis is put on approved methods which can be applied in almost any analytical laboratory. Numerous examples of immunoassays for different pesticides and pollutants (dioxins, polychlorinated biphenyls, mycotoxins) are presented. Besides the respective test features, their applicability for residue determinations in biological samples is kept in the foreground. The advantages and drawbacks of the immunoassays are discussed in comparison with conventional analytical methods. An outlook to future application fields for immunoassays and new trends (e.g. the utilization of monoclonal antibodies) is presented.

Environmental Pollutants↗