I am carrying out chromatographic profiling to differentiate two plant species by TLC. One of the species presents a characteristic band with Rf at approximately ~0.40, while the other species presents a band around 0.38. One of the bands is yellow using 5% sulfuric acid, and the other is gray, for this reason I believe they are different compounds, but I would like greater separation between the two, using the same chromatographic system. The mobile phase that showed the best results was Chloroform: acetone (90:10) tried a more polar phase such as chloroform: ethanol (70:30) and other more non-polar phases such as Toluene: chloroform: acetone (40:25:35), however Didn't get good results with any of them. The distance of the route I am using is 10cm. Can someone help me? I believe that my compound of interest is from the lignan class, but I need to confirm.
Sir please let me know first, at what wavelength you have seen the band's? Is it at long or short wavelength?
Then Sir you can try few drop of Glacial Acetic acid for better band spectrum and I specifically prefer you to use Ethyl acetate instead of acetone.
Bipul Das Chowdhury In visible light my band of interest is yellow, in long wavelength it appears as a brown band. With ethyl acetate the bands remained at the same Rf. I'm gonna try with acetic acid. Thank you
If the Rf value is similar, If the normal phase column is used, try to use the reverse phase for separation. If it is the reverse phase, use a column with a small particle size and high column efficiency for separation.
If the molecular weight difference is large, it can be filtered by gel, but the molecular weight difference should be more than 2 times.
For those with charges, we can try using ion exchange.
If there is a specific adsorption phenomenon, Protein A can be used.
- Badges
- Science topic