I'm doing columm chromatography to isolate and separate secondary metabolic of Garcinia cochinchinensis seeds, but I'm with difficulty, some parts of the samples are adsorving by the silica gel in the moment of the elution. Is it a problem of temperature or used solvent? During the elution, the silica gel is getting colored and when I increase the polarity of the solvent, the silica continues colored and I don't obtained all separated sample. What was supposed to be 40 mg in the fraction, I get 8 mg for example. Is it a room temperature issue and the solvent evaporates creating air bubbles inside the chromatography column? Please, someone help me, I need isolate some compounds to defend my thesis :/. To work with columm chromatography is my main and painful difficulty in obtaining isolated and purified compounds.
Is the problem "air" bubbles in the column (where did the air come from?) or evaporated solvent bubbles? If the later how about chilling the column?
And first thing I would suggest is longer extraction with low polariy solvent
The first thing that comes to mind is that this is not an optimal eluent for the portion of the samples that are adsorbed by silica gel. Temperature, it seems to me, should not affect adsorption that much, unless it is too extreme. It might make sense to change the composition of the eluent or use step elution to extract the adsorbed part of the sample.
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