all figures
COPYRIGHT
Inst.f.Chromatography

Web Design
                       µ-Planar Liquid Chrom.

scroll bar -->

36 check plate qu

46checking plate quality

Figure 36 : µ-PLC is not free from the danger to produce systematically falsified data.
It is clearly visible, that the analyst has set the chromatogram center point wrong. He tried to test the HPTLC plate layer thickness. He used multi integration with 8 tracks, standard track width, 45 degree angle. He needs only the SORBFIL 2.00 figure and realizes, the real chromatogram center (the red point in the figure center above) of this ONE sample run has been systematically wrong positioned. The equal long tracks reach the chromatogram front (position = green point above) correctly only with no. 8, 1 and 2. But a next critical look will tell him: this HPTLC plate is nevertheless bad quality. The area has a gradient. The plate shows a substance selectivity RED circle versus BLUE circle expressed as circle diameter, which difffers clearly between the sector (clock value) 9:00 through 12:00 till 3:00 with the sector 4:30 to 7:00. Accurately done µ-PLC with a complex color test mix given correctly into the plate center provides most sensitively a quality test of a HPTLC plate over its entire area.