Figure 23 : Chromatographers are interested in well reproducable chromatograms. The special advantage of circular chromatography is the length of the substance bow or circle. Thus quantitation can be made on many neighbored parts of a bow or along a circle. As N = 4 is the optimum amount of repeated measurments in analytical statistics ( optimum based on precision versus costs of time and material ). Above are four compared chromatograms and the mean of these four as the fifth one over lapped. The overlapping is so perfect because the signal position (from the plate center to the front circle ) and the signal size are unexpectadly equal. This is no repeatability, but comparability. The single chromatiogram results from, the integration of a chromatogram track starting in the plate center and ending at the front circle. The four tracks have been measured at differing angle positions. Above you can see the Rf scale. But in µ-PLC we move the sample to a start circle which has nothing to with chromatography but with the displacement by a strong eluting solvenmt - the focussing liquid. The only chromatography related value is the position of the circular mobile phase front. The analysts takes a photo, concentrates the figure pixel to a standard value (see in the page - or chapter - under µ-PLC specialities), loads the pixel data into the circular multi integration program SORBFIL version 2.0, Clicks to the plate center position and the front circle position, gibves a few further commands, selects the scan track width, the angle change in degree, the number of to be compared tracks, the software multi integrates. The analyst decides for the length of the tracks ###
