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Thin-layer Chromatography with Flame Ionization Detection
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trendsin analyticalchemistry,vol. 7, no. 8,1988
Nevertheless it should be noted that there are some limitations of the analytical utilization of the technique, e.g. it can be used for only a few elements and, only in the solid state. MGssbauer spectroscopy cannot be considered as a tool for trace element determination since a Miissbauer atom can only be identified if the matrix materials are present in less than lOO-fold excess. The conditions of detectability and of quantitative analysis of a phase in a complex absorbent is that at least 5-10% of all Miissbauer atoms should be present in the phase in question. The sensitivity of the method can be improved by increasing the measuring time and the thickness of the sample up to an optimal limit. The investigation of samples enriched in the Miissbauer active isotope (e.g. samples prepared by using 57Fe instead of natural iron) also improves the sensitivity. The accuracy of quantitative analysis depends on the quality of the Miissbauer spectrum (the resolution of the Miissbauer lines, apparatus factors, counting statistics, etc.) and on the intensity ratio of the spectrum components. The least error can be
achieved with MGssbauer subspectra of similar in- ’ tensities. Considering all the factors influencing the accuracy of quantitative analysis we may estimate the relative error to be about +5-20%. This is, however, acceptable for many applications and commensurate with the accuracy of other similar techniques such as X-ray diffraction.
References 1 G. K. Wertheim, Mijssbauer Effect, Principles and Applications, Academic Press, New York, 1964. 2 N. N. Greenwood and T. C. Gibb, Mijssbauer Spectroscopy, Chapman and Hall, London, 1971. 3 A. V&es, L. Korecz and K. Burger, Miissbauer Spectroscopy, Elsevier, Amsterdam, 1979. 4 M. J. Graham and M. Cohen, Corrosion, 32 (1976) 432. 5 H. Jr. Leidheiser, I. Czak6-Nagy, M. L. Varsanyi and A. VCrtes, .I. Electrochem. Sot., 126 (1979) 204.
Dr. Ilona Czakb-Nagy and Professor Attila Virtes are at the Laboratory of Nuclear Chemistry, EBtv& University, Puskin u. ll13, H-1088 Budapest, Hungary.
Flame ionization detection for thin-layer chromatography Thin-layer Chromatography with Flame Ionization Detection, 44. Rannj, Reidel Publishing Co., 1987, Dfl. 125.00 (198 pages) ISBN 90277-1 973-X In the past years, a rather large number of meeting reports, book reviews and regular contributions in TrAC has been devoted to planar (or: thinlayer) chromatography (TLC). As B. Renger recently stated in this journal, planar chromatography obviously is on the way to becoming established as an original method within the analytical chromatographic techniques. Today, these techniques must increasingly display good selectivity as well as high sensitivity. One of the ways in which this goal can be reached, is by coupling one’s separation technique, i.e. in this case TLC, with a powerful mode of detection from another area of chromatography. One well known combination is
TLC with flame ionization detection (TLC-FID), which was introduced
in the late 1960s and which has, since then, acquired a certain popularity in, e.g., medicine and biology, lipid chemistry and the characterization of crude oils. Suitable equipment (the Iatroscan) and re-usable TLC rods with a sintered silica layer (Chromarods) have been commercially available for over a decade. Part I (ca. 80 pages) of the present book provides basic information on TLC itself, and on the procedures, operational parameters and optimal use of TLC-FID. This part is well written and highly informative, and provides all the technical information a newcomer to the field will require when setting up his own line of research or, more likely, of application. Part II (ca. 90 pages) deals with specialized applications in various fields. As is to be expected, much attention is devoted to the determination of lipids, with separate sections on their isolation from biological material and the accuracy and precision of the technique. Steroid com-
pounds, fats and oils, phospholipids, and surfactants and detergents also are major application areas. In a final, rather short (5 pages) Part III, new perspectives are discussed which mainly are of a technical nature. Of most interest to the general reader is the marketing of a flame thermionic ionization detector which has a high selectivity towards nitrogenand halogen-containing compounds. The number of applications in this area is, however, so far rather limited. As the author states in his introduction, the development of TLCFID is far from complete, and a further improvement of the quality of the sintered silica layers and, even more so, of the detection systems is to be expected. The present book, with its 328 references and its application-oriented approach, nicely summarizes the state of the art. It can therefore be considered a valuable addition to the chromatographic literature. U.A.Th. BRINKMAN Udo A.Th. Brinkman is at the Department of Analytical Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.
trendsin analyticalchemistry,vol. 7, no. 8,1988
Nevertheless it should be noted that there are some limitations of the analytical utilization of the technique, e.g. it can be used for only a few elements and, only in the solid state. MGssbauer spectroscopy cannot be considered as a tool for trace element determination since a Miissbauer atom can only be identified if the matrix materials are present in less than lOO-fold excess. The conditions of detectability and of quantitative analysis of a phase in a complex absorbent is that at least 5-10% of all Miissbauer atoms should be present in the phase in question. The sensitivity of the method can be improved by increasing the measuring time and the thickness of the sample up to an optimal limit. The investigation of samples enriched in the Miissbauer active isotope (e.g. samples prepared by using 57Fe instead of natural iron) also improves the sensitivity. The accuracy of quantitative analysis depends on the quality of the Miissbauer spectrum (the resolution of the Miissbauer lines, apparatus factors, counting statistics, etc.) and on the intensity ratio of the spectrum components. The least error can be
achieved with MGssbauer subspectra of similar in- ’ tensities. Considering all the factors influencing the accuracy of quantitative analysis we may estimate the relative error to be about +5-20%. This is, however, acceptable for many applications and commensurate with the accuracy of other similar techniques such as X-ray diffraction.
References 1 G. K. Wertheim, Mijssbauer Effect, Principles and Applications, Academic Press, New York, 1964. 2 N. N. Greenwood and T. C. Gibb, Mijssbauer Spectroscopy, Chapman and Hall, London, 1971. 3 A. V&es, L. Korecz and K. Burger, Miissbauer Spectroscopy, Elsevier, Amsterdam, 1979. 4 M. J. Graham and M. Cohen, Corrosion, 32 (1976) 432. 5 H. Jr. Leidheiser, I. Czak6-Nagy, M. L. Varsanyi and A. VCrtes, .I. Electrochem. Sot., 126 (1979) 204.
Dr. Ilona Czakb-Nagy and Professor Attila Virtes are at the Laboratory of Nuclear Chemistry, EBtv& University, Puskin u. ll13, H-1088 Budapest, Hungary.
Flame ionization detection for thin-layer chromatography Thin-layer Chromatography with Flame Ionization Detection, 44. Rannj, Reidel Publishing Co., 1987, Dfl. 125.00 (198 pages) ISBN 90277-1 973-X In the past years, a rather large number of meeting reports, book reviews and regular contributions in TrAC has been devoted to planar (or: thinlayer) chromatography (TLC). As B. Renger recently stated in this journal, planar chromatography obviously is on the way to becoming established as an original method within the analytical chromatographic techniques. Today, these techniques must increasingly display good selectivity as well as high sensitivity. One of the ways in which this goal can be reached, is by coupling one’s separation technique, i.e. in this case TLC, with a powerful mode of detection from another area of chromatography. One well known combination is
TLC with flame ionization detection (TLC-FID), which was introduced
in the late 1960s and which has, since then, acquired a certain popularity in, e.g., medicine and biology, lipid chemistry and the characterization of crude oils. Suitable equipment (the Iatroscan) and re-usable TLC rods with a sintered silica layer (Chromarods) have been commercially available for over a decade. Part I (ca. 80 pages) of the present book provides basic information on TLC itself, and on the procedures, operational parameters and optimal use of TLC-FID. This part is well written and highly informative, and provides all the technical information a newcomer to the field will require when setting up his own line of research or, more likely, of application. Part II (ca. 90 pages) deals with specialized applications in various fields. As is to be expected, much attention is devoted to the determination of lipids, with separate sections on their isolation from biological material and the accuracy and precision of the technique. Steroid com-
pounds, fats and oils, phospholipids, and surfactants and detergents also are major application areas. In a final, rather short (5 pages) Part III, new perspectives are discussed which mainly are of a technical nature. Of most interest to the general reader is the marketing of a flame thermionic ionization detector which has a high selectivity towards nitrogenand halogen-containing compounds. The number of applications in this area is, however, so far rather limited. As the author states in his introduction, the development of TLCFID is far from complete, and a further improvement of the quality of the sintered silica layers and, even more so, of the detection systems is to be expected. The present book, with its 328 references and its application-oriented approach, nicely summarizes the state of the art. It can therefore be considered a valuable addition to the chromatographic literature. U.A.Th. BRINKMAN Udo A.Th. Brinkman is at the Department of Analytical Chemistry, Vrije Universiteit, De Boelelaan 1083, 1081 HV Amsterdam, The Netherlands.