ABSTRACT
TLC is an off-line process in which the various stages
(Fig. 1) are carried out independently. The advantages of
this arrangement using an open, disposable layer com-
pared with an on-line column process such as HPLC
include the possibility of separating up to 70 samples
and standards simultaneously on a single plate, leading
to high throughput, low cost analyses and the ability to
construct calibration curves from standards chromato-
graphed under the same conditions as the samples; analyz-
ing samples with minimum sample preparation without
fear of irreversible contamination of the column or carry-
over of fractions from one sample to another as can occur
in HPLC with sequential injections; and analyzing a
sample by use of multiple separation steps and static post-
chromatographic detection procedures with various uni-
versal and specific visualization reagents, which is
possible because all sample components are “stored” on
the layer without chance of loss. TLC is highly selective
and flexible because of the great variety of layers that is
available commercially. It has proven to be as sensitive
as HPLC in many analyses, and solvent usage per sample
is extremely low.
