General Catalogue Chemistry - BECO Internacional LTDA.

Environment analysis - food chemistry - dyes -
biochemistry - pharmaceuticals and drugs cosmetics
- organic chemistry.
When using thin-layer chromatography as an
analytical method the mixture to be separated is
applied to a glass or plastic plate which has been
prepared by applying a thin layer of silica gel, for
instance. The plate is then placed upright in a
glass tank filled with liquid to a point just below
that at which the liquid would come into contact
with the spot of material to be analyzed. The
liquid (the mobile phase) rises on account of the
capillary action of the fine-grained silica gel (the
stationary phase).
The more soluble the components of the mixture
in the mobile phase, the further they will be
661 055
Chromatography paper
Medium propagation speed, 25 sheets
Dimensions: 580 x 600 mm
661 052
Filter paper
For tank saturation, 50 pcs.
Dimensions: 190 x 580 mm
661 035
Round filter
Diameter: 125 mm
Quantity: 100
taken along by the mobile phase. Wide differences
in the solubility of the components in the
mobile phase will consequently result in greater
separation on the thin-layer plate.
In addition to the differing solubility, the separation
of the mixture will also be brought about by
the interactions between the silica gel (the stationary
phase) and the components in the mixture.
The better a component adheres to (is absorbed
by) the silica gel, the more slowly it will be swept
along with the mobile phase.
The plate is removed shortly before the mobile
phase reaches the upper edge; it is then dried.
Colored materials will be identified immediately.
Colorless substances can usually be made visible
by spraying them with a color indicator
Paper and foils for chromatography
chromatography
Prepared films for thin-layer chromatography - plastic backing material
Cat. No. Stationary phase Size [mm] Quantity Remark
661 049
661 059
661 060
661 061
661 062
661 065
Chromatography
(e.g. ninhydrin for amino acids). Viewing under
ultraviolet light is often helpful; this will make
visible those substances which fluoresce under
UV light. Some thin-layer plates are additionally
coated with a fluorescent indicator. This makes
many colorless substances visible which do not
fluoresce under the UV lamp.
Cellulose 80 x 40 50
Cellulose 200 x 50 50
Silica gel 200 x 50 50 UV indicator
Cellulose 200 x 200 25
Silica gel 200 x 200 25 UV indicator
Silica gel 80 x 40 50 UV indicator
LEYBOLD DIDACTIC · GENERAL CATALOGUE CHEMISTRY
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