Appendix 1 Applied HPLC Theory

The principles and results of HPLC theory that are useful in everyday work have been presented in Chapters 2 and 8. The following is a comprehensive repetition and summary of important equations. Derivations and references are not presented here both can be found in the two chapters mentioned and in many sections of the book (see Index) references can also be found in the paper on which this appendix is based.  

The basis of the considerations is an HPLC column of typical dimensions, 25 cm in length Lc and 4.6 mm inner diameter d, which is packed with a stationary phase of 5 (tm particle diameter d. Let us investigate what can be calculated from these and 

By means of the reduced plate height h it is possible to calculate N. With the assumption that the column is packed very well (not excellently), i.e. that h = 2.5, we obtain  

Chromatogr., 334, 197 (1985) see also M.A. Stone, Mathematics of optimization and scaling for the practical chromotographer, J. Liq. Chromatogr. Rel. Tech., 30, 605 (2007), including the optimization of gradients. 

Practical High-Performance Liquid Chromatography, Fifth edition Veronika R. Meyer 

The value for N of 20000 is rather high and in fact is seldom reached by 25 cm HPLC columns (J=5pm) used routinely. A value of 10000 or 15000 is, unfortunately, more realistic. 

Practical High-Performance liquid Chmmalogruphy, Fourth edition Veronika R. Meyer 2004 John Wiley Sons, Ltd ISBN 0-470-09377-3 (Hardback) 0-470-09378-1 (Paperback) 

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