Polyamide thin layer chromatography is the most convenient method for the separation of phenolic substances ever found. Pl. find the original reference paper attached for this method. I would suggest to proceed with this method. But silica gel can also be used for both.

Silica gel would be good for flavonoids and phenolics too. Try solvent system using Chloroform: Methanol in various combinations. Try Toluene: Ethyl Acetate: Formic Acid [7:5:1 v/v/v/v/v] for phenolics and ethyl acetate: glacial acetic acid:formic acid: water [100:11:11:25, v/v/v/v/v] for flavonoids. This solvent systems have been tested successfully for gallic acid, rutin and quercetin. Hence can be used as a reference.

Gud luck and regards

Silica gel is best for that,

The separation can be conducted using silica gel. You can also avoid tailing of spots (phenols and acidic compounds) treating both eluent and silica gel mixture with gaseous CO2 before packing the column and during elution.

Polyamide thin layer chromatography is the most convenient method for the separation of phenolic substances ever found. Pl. find the original reference paper attached for this method. I would suggest to proceed with this method. But silica gel can also be used for both.

Silica gel would be good for flavonoids and phenolics too. Try solvent system using Chloroform: Methanol in various combinations. Try Toluene: Ethyl Acetate: Formic Acid [7:5:1 v/v/v/v/v] for phenolics and ethyl acetate: glacial acetic acid:formic acid: water [100:11:11:25, v/v/v/v/v] for flavonoids. This solvent systems have been tested successfully for gallic acid, rutin and quercetin. Hence can be used as a reference.

Gud luck and regards

I think you should try using some adsorption resins or use RP C18 silica for purification of phenolics. Use solvent like aqueious ethanol by altering the polarity by slovent gradient.

Extraction in 70% methanol followed by resin HP-20, XADs followed by C-18.

Have a look at one of my papers...maybe it helps. "Bioactive polyphenols from muscadine grape and blackcurrant

stably concentrated onto protein-rich matrices for topical

applications" International Journal of Cosmetic Science, 2013, 1–8, N. Plundrich, M. H. Grace, I. Raskin and M. Ann Lila, but you should also be able to download it from my profil, if you want. I extracted/ measured phenolic acids, total ANC per HPLC column, if you want to do PAC I also do have an HPLC method they could help. Good luck!

Dear Jovale, I suggest you read the article entitled, "Techniques for Analysis of Plant Phenolic Compounds by Ali Khoddami, Meredith A. Wilkes and Thomas H. Roberts" Molecules 2013, 18, 2328-2375; It is an excellent review on every aspect of analysis of plant phenols. The authors wrote that "Sephadex LH-20, polyamide, Amberlite, solid phase extraction (SPE) cartridges and styrene–divinylbenzene (XAD 4, XAD16, EXA-90, EXA 118, SP70), acrylic resins (XAD-7, EXA-31) are examples of regularly applied materials to purify phenolics from crude sample extracts" Good luck!

Have a look at my paper that I used preparative column chromatography for separation phenolic compounds from thyme and...

" Antibacterial effect of effective compounds of Satureja hortensis and Thymus vulgaris essential oils against Erwinia amylovora."

Thank you for all the valuable information. I will try some of the suggestions posted here.

I can recommend you the attached literature

Embedded polar group phases such as amide, carbamate, urea are very effective at separating closely related phenolics. The silica/amide suggestions are great for crude extraction, but reversed phase using such columns as amide will likely provide improved analysis of said extracts

Dr. Tongco, I think the best way to perform the separation of phenolic acids and small flavonoids from crude plant extracts is by HPLC with a RP-18 column (for example, a Purospher STAR endcapped or Lichrospher), using methanol or acetonitrile and formic acid.

Plese see the atached article.

Also a phenyl-modified reversed phase material seems to be valid.

I worked with phenolic compounds on Aerosol particles.

On the other hand, if you have very polar molecules try the HILIC technique.

Both suggestions can be coupled with MS if needed.

Sephadex LH-20 eluted with pure methanol can help quite a lot. It is a fast a very simple method for at least partial purification of phenolics.

I've used ion exchange followed by LH-20 in methanol, and finishing with C18 to purify phenolics. Silica can work as well.

Some references:

http://www.isco.com/WebProductFiles/Applications/101/Poster_and_Paper_Reprints/Purification_of_Phenolic_Flavonoids.pdf

Information on using the ion exchangers for phenolics:

http://www.isco.com/WebProductFiles/Applications/101/Application_Notes/AN87_RediSep%20Rf_SAX_Column_Applications.pdf

I concur with Dr. Canas above. HPLC with c-18 resins in methanol + acid is a generally preferred method.

Polyamide resin also can be used. I ran a gradient starting with water to 100% methanol, another gradient from methanol to methanol to 100% acetone, then acetone to 100% water containing 5% ammonium hydroxide (3 gradients total).

I recommend the method of the attached file.

http://www.ncbi.nlm.nih.gov/pubmed/19053354

I've used reversed phase column (C18) column with gradient mobile phase 0.1% formic acid and methanol for separation MeOH extract from plant. This solvent system have been tested for separation of 15 standard phenolic acids.

Thank you for your valuable contributions!

Is it for analysis or for preparative chromatography?

In the last case, I can cive you a list of references.

Based on the above suggestions can I come to a conclusion that silica gel can also be used??

@Leena-

It can, depending on the compound. Here is a review:

http://www.teledyneisco.com/en-us/liquidChromatography/Chromatography%20Documents/Application%20Notes/Purification%20Strategies%20for%20Flavones%20and%20Related%20Compounds%20App%20Note.pdf#search=flav%2A

To separate the phenolic compounds from the first ethanol amount, fractionate chloroform, ethyl acetate, and n-butanol with solvents. Chloroform fraction is separated in a column with silica gel in the system of gasoline-ethyl acetate or benzene-ethanol in different ratios. For ethyl acetate, use the chloroform-methanol solvent system. And, for individual separation, you can try gel chromatography Sephadex LH-20.