(c) the plate number for each compound using widths at 1/2 -height;
(d) the resolution of the two compounds, Rs.
(13) Two compounds were separated by HPLC with an Rs value of 0.75, the plate number for the
second compound being 4500. Calculate the number of plates required to obtain resolutions of (a) 1.0
and (b) 1.5.
(14) The distances travelled by five compounds and the solvent front after a TLC separation on silica
gel were as follows:
Compound Distance travelled, cm
solvent 12.5methyl stearate 9.1cholesterol 1.5α-tocopherol (vitamin E) 5.6
methyl oleate 9.1squalene (hydrocarbon) 10.3Calculate the Rf values of each compound and comment on the relative values.
Further Reading
Anderson, R., Sample Pre-treatment and Separation, Wiley, Chichester, 1987
Braithwaite, A. & Smith, F. J., Chromatographic Methods (4th edn), Chapman & Hall, London, 1985.