For scoring and cutting of glass TLC-plates The scoring and cutting of glass TLC-plates is a routine in many chromatography laboratories either to Economies on plate usage, or to cut the plate following separation for future quantitation . The TLC-plate cutter consist of a high quality carbide scribe mounted into a movable plastic head.
 

A concave mirror focuses the light from a light source onto the entry slit. The spectral band at the grating is reflected by means of a second concave mirror onto the adjustable measuring slit. A third concave mirror and a plane mirror tramsmit the measuring beam to the sample being measured. This sample beam is also split and transmitted to the reference detector. The reflectance detector measures the light scattered by the sample, the transmission detector measures the light which is trasmitted through the sample.
 

The UV detection methods are amongst the most sensitive means of detection available for thin-layer chromatography. Substances fluoresce brightly on a dark background in long-wave UV light at 366 nm. This method demands high light density. It is important, in order to increase the contrast, that the visible portion be filtered out by means of a special filter. If the TLC plate contains a fluorescent indicator then at 254 nm the substance spots appear as dark spots against a bright fluorescent background. White light is required for colou- red chromatograms.