Further Reading

Fried B and Sherma J (1999) Thin Layer Chromatography, Techniques and Applications, 4th edn. New York, NY: Dekker.

Fried B and Sherma J (1996) Practical Thin Layer Chromatography - A Multidisciplinary Approach. Boca Raton, FL: CRC Press.

Rabel F (1974) Polyamide Chromatography. In: Grushka E (ed.) Bonded Stationary Phases in Chromatography, pp. 113-137. Ann Arbor, MI: Ann Arbor Science Publishers.

Stahl E (ed.) (1969) Thin Layer Chromatography, 2nd edn. New York, NY: Springer-Verlag.

Touchstone JC (1992) Practice of Thin Layer Chromato-graphy, 3rd edn. New York, NY: Wiley-Interscience.

Consequently, the identification of components separated by planar methods based solely on RF values and UV or fluoresence properties will always leave a higher degree of uncertainty about the true identity of the compounds present. Positive identification of unknowns has to be made by subjecting the analyte to a spectroscopic technique such as mass spectrometry.

As with other methods of chromatography, the use of MS as a TLC/HPTLC detector involves the detection and identification of the analyte in the presence of interfering materials from the chromatographic mobile and stationary phases. An analyte separated by planar techniques will be presented to a mass spectrometer along with the stationary phase, any organic phase modifier present, binding agents and fluorescent indicators. It is possible that residual solvents from the mobile phase, some of which may have high boiling points may be present. At best, the mass spectra obtained from a single spot taken from, for example, a silica gel HPTLC plate, will contain ions from the analyte with contributions from all these other compounds. When ionization is by fast atom bombardment (FAB) the situation is exacerbated by the formation of matrix and salt ions. Although useful information can be obtained from TLC/HPTLC-MS experiments, the information so obtained can be improved by using tandem mass spectrometric methods.

Solar Panel Basics

Solar Panel Basics

Global warming is a huge problem which will significantly affect every country in the world. Many people all over the world are trying to do whatever they can to help combat the effects of global warming. One of the ways that people can fight global warming is to reduce their dependence on non-renewable energy sources like oil and petroleum based products.

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