Mass spectrometry is one of the most specific and
informative of the analytical methods. Because TLC is a form
of planar chromatography it would be logical to use a form of
surface mass spectrometry, such as time-of-flight secondary ion
mass spectrometry (ToF-SIMS), to analyze TLC plates. Over
the past few years a series of publications has described the
coupling of ToF-SIMS and TLC [4–6]. It has, however, recently
been concluded that ‘‘direct analysis of thin layer chromatography
plates with secondary ion mass spectrometry (SIMS)
yields no satisfactory results [6].’’ We do not disagree with this
general statement. Indeed, we are only aware of one successful,
direct analysis of a TLC plate by SIMS, which used quaternary
amines as analytes [7].We have, however, found two additional