Definition of Analytical Chemistry

WPAC (1993) Edinburgh definition of analytical chemistry see Kellner, R (1994)... 

The definition of analytical chemistry was given by the FECS [1] in 1993 and adopted by IUPAC ... 

Ecotoxicological considerations and the effort to achieve an increasingly accurate description of the state of the environment challenge analytical chemists who need to determine increasingly lower concentrations of various analytes in samples that have complex and even non-homogenous matrices. The newly coined expression "analytics" emphasizes the interdisciplinary nature of available methods for obtaining information about material systems, with many methods that exceed the strict definition of analytical chemistry. Drawing on the disciplines of chemistry, physics, computer science, electronics, material science, and chemometrics, this book provides in depth information on the most important problems in analytics of samples from aquatic ecosystems. 

The Division of Analytical Chemistry of the American Chemical Society provides a comprehensive definition of analytical chemistry, which may be found on their website (vyww.acs-analytical.duq.edu/whatisanltvcalchem.html). It is reproduced, in most part, here ... 

More comprehensive contemporary definitions of analytical chemistry have been proposed [7], [8], underscoring above all the complexity of the discipline—which the authors of this introduction were also forced to confront. 

Valc cel, M. (1997) A modem definition of analytical chemistry. Trends Anal. Chem., 16, 124-131. 

This definition outlines in very broad terms the scope of analytical chemistry. When a completely unknown sample is presented to an analyst, the first requirement is usually to ascertain what substances are present in it. This fundamental problem may sometimes be encountered in the modified form of deciding what impurities are present in a given sample, or perhaps of confirming that certain specified impurities are absent. The solution of such problems lies within the province of qualitative analysis and is outside the scope of the present volume. 

However, now and then analytical chemists feel uneasy with such kinds of definitions which do not reflect completely the identity and independence of analytical chemistry. Chemists of other branches (inorganic, organic, and physical chemists) as well as physicists and bioscientists also obtain information on inanimate or living matter using and developing high-performance analytical instruments just as analytical chemists do. 

The first definition that is focused directly on the role of analytical signals was given by Pungor who characterizes analytical chemistry as a science of signal production and interpretation (Veress et al. [1987], Lewenstam and Zytkow [1987]). Zolotov [1984] characterized chemical, physicochemical and physical methods of analytical chemistry as follows All of them, however, have the same feature it is the dependence of signal on analyte... 

To overcome the unsatisfactory situation in the understanding the meaning of analytical chemistry at the end of the last century, an international competition was organized in 1992 by noted European analytical chemists and the Fresenius Journal of Analytical Chemistry to characterize analytical chemistry as an autonomous field of science by a topical and proper definition. The title of this competition was Analytical Chemistry - today s definition and interpretation and 11 out of 21 contributions were published in Fresenius J Anal Chem (Fresenius and Malissa [1992] Cammann [1992] Valcarcel [1992] Zuckerman [1992] Zhou Nan [1992] Koch [1992] Perez-Bustamante [1992] Ortner [1992] Danzer [1992] Green [1992] Stulik and Zyka [1992] Kuznetsov [1992]). 

All these definitions express essential aspects of analytical chemistry and the analytical work. Some others - with originality - could be added, such as that from Murray [1991] who characterized analytical chemistry briefly and aptly as the science of chemical measurements . 

Hulanicki A., Glab S., Ingman F., Chemical sensors definitions and classification. Commission on General Aspects of Analytical Chemistry, Pure Appl. Chem. 1991 63 1247. 

The following list of definitions, though by no means exhaustive, will help both in the study and practice of analytical chemistry. 

A broadly accepted definition of process analytics is difficult to capture as the scope of the methodology has increased significantly over the course of its development. What was once a subcategory of analytical chemistry or measurement science has developed into a much broader system for process understanding and control. Historically, a general definition of process analytics could have been ... 

This definition can be described as analysis in the process and is closely related to the traditional role of analytical chemistry in process control. The classical scope of a process analytical method is it to supplement the control scheme of a manufacturing process with data from a process analyzer that directly measures chemical or physical attributes of the sample. 

Due to the particular effects of the microwaves on matter (namely dipole rotation and ionic conductance), heating of the section, including its core, occurs instantaneously, resulting in rapid breakdown of protein crosslinkages. Furthermore, the extraction and recovery of a solute from a solid matrix with microwave heating is routinely obtained in the field of analytical chemistry (Camel, 2001). However, a definite, full explanation of the effects of microwave heating on the molecular aspect of antigen retrieval is awaited. 

According to this definition of reference materials the property values in analytical chemistry usually describe the chemical composition [5, 6]. Reference materials are valid only within the reference system of analytical chemistry. 

It is important to make the distinction between the determination of polymorphic identity and polymorphic purity. The former is essentially a qualitative determination, asking the question, Ts a particular polymorph present in a given sample The latter is a question of quantitative analysis, and it is generally (though not always) assumed that the sample is chemically pure, so the analytical problem to be addressed is the determination of the relative amounts of different polymorphs in the sample. Recalling that different polymorphs are for all intents and purposes different solids, the determination of polymorphic purity is then no different in principle from quantitative determination of the composition of a mixture of solids. Such quantitative determinations comprise one of the traditional activities of analytical chemistry, especially when the materials are different chemical entities. In those cases, a variety of different analytical methods may be employed. In the case of polymorphic mixtures, or the determination of polymorphic purity, the choice of analytical method is considerably more restricted, and X-ray diffraction is one of the most definitive techniques (see e.g. Stowell 2001). 

Still another major operation in analysis is measurement, which may be carried out by physical, chemical, or biological means. In each of these three areas a wide range in techniques is available. For example, titrimetry is the most common of the chemical methods of measurement, and spectroscopy the most widely used of the available physical methods. In most analytical studies the bulk of the effort is directed to an examination of the theoretical background, experimental limitations, and applications of various techniques of measurement. Since methods of analysis are usually defined in terms of the final measurement step, the impression is often given that this stage constitutes the entire subject of analytical chemistry. Even though the measurement aspect deserves much attention, it should be remembered that the preliminary steps of definition of the problem, sampling, and separation are also critical to the overall process. 

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