title: Chromatographic Methods
author: A. Braithwaite
description: comprehensive and well presented...The chapters are informative and easy ot read...already used widely in teaching institutions and this use will undoubtedly continue in the future because it provides an ideal resource for this purpose. I commend it highly - Journal of Chromatography
zlib_text: Figure 18
  Anticircular chromatogram. (Reproduced with per-
  mission from Fenimore DC and Davis CM (1981) High perfor-
  mance thin-layer chromatography. Analytical Chemistry 53: 252A.)
  with sulfuric acid containing naphthoresorcinol by
  spraying or dipping with this reagent and heating at
  1003C for 5 min. The spots near the origin are sym-
  metrical and compact but those further away are more
  compressed and elongated at right angles to the direc-
  tion of development. The sample was also separated in
  the same chromatographic system, but using linear
  development on a 10�10 cm plate (Figure 15B).
  If the sample is introduced in the mobile-phase
  stream, then separated bands form concentric rings
  on the chromatographic plate, as shown in Figure 16.
  This circular chromatogram demonstrates the separ-
  ation of lipophilic dyes on a silica gel 60 F254 high
  performance TLC pre-coated plate, 10�10 cm (E.
  Merck) with a mobile phase of hexane}chloroform}
  NH3, 70 : 30; the distance of development (from en-