TLC Silica Gel F₂₅₄ Plate

Complies with the requirements prescribed for TLC silica gel plate with the following modifications.

It contains a fluorescent indicator having a maximum absorbance at 254 nm.

Fluorescence suppression Apply separately to the plate at five points increasing volumes (1 µL to 10 µL for normal plates and 0.2 µL to 2 µL for fine particle size plates) of a 0.1% w/v solution of benzoic acid in a mixture of 15 volumes of absolute ethanol and 85 volumes of cyclohexane. Develop over a pathlength of half the plate height using the same mixture of solvents as the mobile phase. After removal of the plate, allow the solvents to evaporate and examine the chromatograms in ultraviolet light (254 nm). For normal TLC plates benzoic acid appears as dark spots on a fluorescent background approximately in the middle of the chromatogram for quantities of 2 µg or greater. For fine particle size plates benzoic acid appears as dark spots on a fluorescent background approximately in the middle of the chromatogram for quantities of 0.2 µg or greater.