The spot of the test sample is loaded on the filter paper using a capillary tube. This spot should always be a concentrated but a very minute one. Capillary tubes are used in paper chromatography, because a small quantity can be taken into the tube without any force. The upper line (solvent front) is drawn on the paper from 2 cm on the top and the bottom line (base line) is drawn from 2 cm from the bottom of the paper. Usually 0.01g of the sample is dissolved in the running solvent (1g). Micro liter quantities are used to spot on the paper by a capillary tube. The diameter of the spot should be only up to few mili meters. The spotting should be done several times in order to get a concentrated spot. This filter paper is then placed inside the chamber saturated with the solvent to develop the chromatogram. The chromatogram is then heated in an oven to high temperatures. This can be done not only by an oven but also using a fan, air etc.
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