Microscopy chemical

Sheppard C J R 1987 Scanning optical microscopy Adv. Opt. Electron Microscopy 10 1-98 Cooke P M 1996 Chemical microscopy Anal. Chem. 68 333-78... 

C. W. Mason, Handbook of Chemical Microscopy 4th ed., John Wiley Sons, Inc., New York, 1983. 

W. C. McCrone, Fusion Methods in Chemical Microscopy, Interscience Pubhshers, New York, 1957. 

The current trend in analytical chemistry applied to evaluate food quality and safety leans toward user-friendly miniaturized instruments and laboratory-on-a-chip applications. The techniques applied to direct screening of colorants in a food matrix include chemical microscopy, a spatial representation of chemical information from complex aggregates inside tissue matrices, biosensor-based screening, and molec-ularly imprinted polymer-based methods that serve as chemical alternatives to the use of immunosensors. 

Navratil, M., Mabbott, G.A., and Arriaga, E.A., Chemical microscopy applied to biological systems. Anal. Chem., 78, 4005, 2006. 

Knoll, B. and Keilmarm, F. (1999) Nearfield probing of vibrational absorption for chemical microscopy. Nature, 399, 134-137. 

MB Kuhnert. Status and future of chemical microscopy. Pure Appl Chem 10(2) 133-144, 1965. 

Valuable results with Tof-SIMS imaging have been obtained e.g., with paper samples. The distribution of papermaking chemicals on the surface of coated and uncoated papers is very important for its further treatment, such as printing. Figure 16 [70] is an example of use of the technique for chemical microscopy analysis of paper surfaces. 

Probably the most extensive use of particle morphology and microscopy has been in the area of chemical microscopy. With this approach, derivatives of the analyte species are prepared, crystallized, and identified through the morphological characteristics of these derivatives [21]. Most of these applications have been superseded by modem methods of analysis, but the microscopic method can still be used by skilled practitioners for the study of trace quantities of analyte. The literature developed during the heyday of chemical microscopy is too large to be reviewed here, but advances in the field are still chronicled in the Annual Reviews issue of Analytical Chemistry [22]. A substantial review of the optical characteristics of organic compounds is available [23]. 

One of the most systematic investigations into the use of organic chemical microscopy was made by Dunbar and his associates, who used a series of specific reagents to develop specific tests for various functional groups. Methods were developed for amines [24,25], carboxylic acids, anhydrides, and acid chlorides [26,27], aldehydes and ketones [28], hydroxy compounds [29], amino acids [30], and cations [31]. 

H.-H. Emons, H. Keune, and H.-H. Seyfarth, Chemical Microscopy, in Comprehensive Analytical Chemistry, Vol. 16, Elsevier, Amsterdam, 1982. 

For inorganic substances, chemical reactions may be carried out on a small scale on microscope slides, the crystallization of reaction products being watched. Tests for particular ions or atom groups have been devised, the criterion of identity being, not solubility or colour, as in macroscopic qualitative chemical analysis, but crystallographic properties. For information on such methods, see Handbook of Chemical Microscopy, by Chamot and Mason (1958). 

The availability of laser scanning confocal fluorescence microscopy,68 first commercially offered in the 1980s, enabled a major advance in chemical microscopy imaging convenient summaries are available in the Handbook of Biological Confocal Microscopy.69 Confocal fluorescence microscopy works by focusing continuous-wave laser illumination to a diffraction-limited spot in a focal... 

Fig. 20 Group selective labeling agents for chemical microscopy by TOF-SIMS. Analysis of a CCOA-labeled (right) and an FDAM-labeled beech sulfite pulp...

CCOA and FDAM are also suitable labels for surface analysis by TOF-SIMS. Both labels exhibit a distinct mass spectrum which can be used to visualize the surface distribution of carbonyl or carboxyl groups across single fibers by chemical microscopy (Fig. 20) (courtesy of Fardim P, Abo Academy Turku, Finland). 

The name of Fritz Feigl will always be associated with spot tests. An article has traced his life and work, from his early years in Europe and his important association with Friedrich Emich, to his later years in Brazil.72 The microscope has been an important instrument in the analytical laboratory since the early nineteenth century. An article has traced the history of chemical microscopy by surveying the important books that have appeared on the subject since 1827,73... 

Cancrinite crystallization, promoted by the joint presence in the reaction system of lithium and a large cation, has been thoroughly investigated, pointing out the specificity of the cationic couple for the synthesized phase. The products obtained have been characterized by means of X-ray diffraction, chemical, microscopy and thermal analyses. A hypothesis on the mechanism of cancrinite formation has been worked out, also on the basis of the preliminary results of structural analysis. 

For a detailed account, see E. M. Chamot and C. W. Mason Handbook of Chemical Microscopy, Volume I (1938) and Volume II (1940) (J. Wiley Chapman and Hall) also A. A. Benedetti-Pichler Introduction to the Microtechnique of Inorganic Analysis (1942) (J. Wiley Chapman and Hall.)... 

L. D. Hall, NMR chemical microscopy, in C. Lunsford, (Ed.), Natural Products Research The Impact of Scientific Advances, The Fifth Philip Morris Science Symposium, pp. 74—105. 

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