I'm assuming this is an unknown compound

What did you use to extract your compounds? The compounds will usually match the polarity of the solvent. As two examples at the extreme, extraction with hexanes will not have many very polar compounds, so solvent systems such a hexane/ether, hexane/toluene, and hexane/ethyl acetate will work for normal phase, and methanol/dichloromethane for reverse phase (non-aqueous reverse phase)

At the other extreme, extraction with water would tend to collect compounds where dichloromethane/methanol is good for normal phase, and water/methanol for reverse phase.

If the organism was extracted with methanol, ethyl acetate, ethanol, or another intermediate polarity solvent, there will be a mixture such that there is no single TLC system that will magically isolate your compound.

If the compound is known, the literature should describe how it was purified. If it purified on silica or C18, use the solvent system used for purification as a starting point for TLC methods. The concentration of solvents may need adjustment, but the same solvents that run a TLC are used for column chromatography.

Dear Sir. Concerning your issue about the suitable solvent system for thin-layer chromatography of marine animals. The mobile phase used in argentation TLC usually consists of two or three components, for example, hexane, petroleum ether, benzene, and toluene. Moreover, small amount of acetone, diethyl ether, ethanol, methanol, or acetic acid may be added to these mobile phases. Of various visualizing agents of spots, those which are most popular for Ag-TLC of fatty acids are 50% ethanol solution of sulfuric acid, phosphomolybdic acid, and a mixture of copper-acetate-phosphoric acid. Another visualizing method is spraying the plates with fluorescent indicator by 2′,7′-dichlorofluorescein in ethanol and next viewing the spots under UV light. I think the following below links may help you in your analysis:

https://www.hindawi.com/journals/jchem/2015/120830/

http://www.phytojournal.com/vol3Issue1/Issue_may_2014/27.1.pdf

http://www.jlr.org/content/12/1/24.full.pdf

Thanks

Remember that you can make few elutions forbthe same plate and spots on it. You can increase the elution strenght each time and evaluate the separation effect.

Regards

G

Dear dont run to shortcut, adjust your mobile phase by yourself by trying various polarity solvents, because, TLC is only dependent on solvent nature and polarity