APPLICATIONS IN ANALYTICAL CHEMISTRY

M. Otto, Chemometrics. Statistics and Computer Application in Analytical Chemistry. Wiley-VCH, Weinheim, 1998. 

M. Otto, Chemometrie Statistik und Computereinsatz in der Analytik, WHey-VCH, Weinheim, 1997 M. Otto, Chemometrics. Statistics and Computer Application in Analytical Chemistry, Wiley-VCH, Weinheim, 1998. 

Finally, a consideration of equilibrium chemistry can only help us decide what reactions are favorable. Knowing that a reaction is favorable does not guarantee that the reaction will occur. How fast a reaction approaches its equilibrium position does not depend on the magnitude of the equilibrium constant. The rate of a chemical reaction is a kinetic, not a thermodynamic, phenomenon. Kinetic effects and their application in analytical chemistry are discussed in Chapter 13. 

Up to this point, our position has been that the elementary processes by which x-rays are absorbed and emitted are free of chemical influences because these processes involve energ levels nearer the nucleus than the levels in which valence electrons are to be found. This simplified position suffices for most x-ray applications in analytical chemistry. Nevertheless, chemical influences on both types of elementary processes have been demonstrated, but only at very high resolution—at much higher resolution than the analytical chemist usually requires. 

Electrogenerated chemiluminescence (ECL) has proved to be useful for analytical applications including organic analysis, ECL-based immunosensors, DNA probe assays, and enzymatic biosensors. In the last few years, the electrochemistry and ECL of compound semiconductor nanocrystallites have attracted much attention due to their potential applications in analytical chemistry (ECL sensors). 

M. Peris, An overview of recent expert system applications in analytical chemistry. Crit. Rev. Anal. Chem., 26 (4) (1996) 219-237. 

The reaction between starch and iodine (or iodine-iodide mixtures) to form an inclusion compound was first reported in 1814 by Colin and de Claubry 131) and has since become familiar to all chemists through its applications in analytical chemistry. Its deep blue colour (kmax 620 nm) has been known for years to result from a linear arrangement of polyiodide within a canal formed by a helical coil of amylose. The helical amylose structure will trap other molecules 132,1331 and other hosts will stabilise polyatomic iodide guests134> 135). 

An early field of application in analytical chemistry is structure elucidation. DENDRAL was one of the first ES in general, designed to the identification of organic compounds from mass spectrometric data (Buchanan and Feigenbaum [1978]). In the 1980s and 1990s a flood of expert systems has been developed in analytical chemistry for different types of application, viz ... 

Otto M (1998) Chemometrics. Statistics and computer application in analytical chemistry. VCH, Weinheim... 

V.B. Kandimalla and H.X. Ju, Molecular imprinting a dynamic technique for diverse applications in analytical chemistry. Anal. Bioanal. Chem. 380, 587-605 (2004). 

Much of the study of ECL reactions has centered on two areas electron transfer reactions between certain transition metal complexes, and radical ion-annihilation reactions between polyaromatic hydrocarbons. ECL also encompasses the electrochemical generation of conventional chemiluminescence (CL) reactions, such as the electrochemical oxidation of luminol. Cathodic luminescence from oxide-covered valve metal electrodes is also termed ECL in the literature, and has found applications in analytical chemistry. Hence this type of ECL will also be covered here. 

Advanced mathematical and statistical techniques used in analytical chemistry are often referred to under the umbrella term of chemometrics. This is a loose definition, and chemometrics are not readily distinguished from the more rudimentary techniques discussed in the earlier parts of this chapter, except in terms of sophistication. The techniques are applied to the development and assessment of analytical methods as well as to the assessment and interpretation of results. Once the province of the mathematician, the computational powers of the personal computer now make such techniques routinely accessible to analysts. Hence, although it would be inappropriate to consider the detail of the methods in a book at this level, it is nevertheless important to introduce some of the salient features to give an indication of their value. Two important applications in analytical chemistry are in method optimization and pattern recognition of results. 

Recently, introductory books about chemometrics have been published by R. G. Brereton, Chemometrics—Data Analysis for the Laboratory and Chemical Plant (Brereton 2006) and Applied Chemometrics for Scientists (Brereton 2007), and by M. Otto, Chemometrics—Statistics and Computer Application in Analytical Chemistry (Otto 2007). Dedicated to quantitative chemical analysis, especially using infrared spectroscopy data, are A User-Friendly Guide to Multivariate Calibration and Classification (Naes et al. 2004), Chemometric Techniques for Quantitative Analysis (Kramer 1998), Chemometrics A Practical Guide (Beebe et al. 1998), and Statistics and Chemometrics for Analytical Chemistry (Miller and Miller 2000). 

SeUeTgren,B.,Molecularly Imprinted Polymers—Man-Made Mimics of Antibodies andTheir Applications in Analytical Chemistry, Elsevier, Amsterdam, the Netherlands, 2001. 

It is generally known that the examined properties and phase behavior of ILs vary on cation and anion structures changing. Some typical trends will be presented in this chapter on the basis of the structural effect on the interactions between counterpart ions (see, for example Ref. 3, the spoon-shaped structure of the unit cell of the l-dodecyl-3-methylimidazolium hexafluoro-phosphate, [Ci2Cilm][PFg]), and between the IL and the solvent, or the coexisting compound. The structure of IL and its interaction with the environment is extremely important in applications in analytical chemistry [4]. 

Several reviews have been published about ILs and analytical chemistry, fortunately now we have main players in this field in one place who kindly agreed f o provide f heir contributions. This book is an attempt to collect experience and knowledge about the use of ILs in different areas of analytical chemistry such as separation science, spectroscopy, and mass spectrometry that could lead others to new ideas and discoveries. In addition, there are chapters providing information of studies on determination of physicochemical properties, fhermophysical properties and activity coefficients, phase equilibrium with other liquids, and discussion about modeling, which are essential to know beforehand, also for wider applications in analytical chemistry. 

Ehmann, W. D. and D. E. Vance. Radiochemistry and Nuclear Methods of Analysis, Wiley, New York, 1991. An up-to-date survey of nuclear chemistry that emphasizes its applications in analytical chemistry. 

The sensitivity of this technique is excellent and its accuracy is greater than that of conventional polarography. This method has found wide application in analytical chemistry. For addnl info on this subject see Refs 6,7,8,10,12,14,16,17,18,19,20,21,22,24,25,26 28,29,30,31 32... 

Wulff G, Biffis A (2001) In Sellergren B (ed) Molecularly imprinted polymers man-made mimics of antibodies and their applications in analytical chemistry. Elsevier, Amsterdam, pp 71-111... 

Due to their specific molecular recognition properties, MIPs have found their main application in analytical chemistry. As outlined in the introduction, the common preparation method of MIPs as bulk polymers, which are subsequently crushed, ground and sieved to obtain particles, is not well adapted to achieve a high separation performance. Thus, the preparation of monolithic MIPs seemed particularly attractive for separation science due to the permeability properties, the easy in situ preparation and the absence of retaining frits. On the other hand, the use of the monolith format is still limited and the strategy of MIP monolith preparation has been little developed in recent years. 

I venture to say that the majority of practical chemometrics applications in analytical chemistry are in the area of instrument specialization. The need to improve specificity of an analyzer depends on both the analytical technology and the application. For example, chemometrics is often applied to near-infrared (NIR) spectroscopy, due to the fact that the information in NIR spectra is generally non-specific for most applications. Chemometrics may not be critical for most ICP atomic emission or mass spectrometry applications because these techniques provide sufficient selectivity for most applications. On the other hand, there are some NIR applications that do not require chemometrics (e.g. many water analysis applications), and some ICP and mass spectrometry applications are likely where chemometrics is needed to provide sufficient selectivity. 

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