Chromatography Forum

can any body recomend procedure for extraction ointment or cream for gc-ms or lc-ms?

We'd try methanol first. If that didn't dissolve your sample, our next tries would be DMF or THF.

What is active components ?
What is basic of ointment ? Emulsion (water /oil, oil/water) , lipofilic melt (parafine, lanoline) , hydrofillic true solution in PEG , thickened with Carbomer true aqueous solution ?


Methanol is good solvent from solved in methanole substancies (such as menthol).
Good operation - will cold extract by - 10 to - 30 C.

What is active components ?

Oftentimes a poster cannot detail what his analyte or his sample matrix is, because it could tip his hand to a competitor. For example, if a company was going to come out with a new product, like a new "category" and thus have a head start on the competition, he would need to keep that information as proprietary, to get a business head start.

Let's say Jergens Lotion wanted to come out with a sunscreen product (and maybe they already have one) - Jergens wouldn't want the competition to know in advance.

Yes of course. But
1) Never ask full recept. But answer : "it painless drug ( aminobenzoic acid derivates in hydrochloric salt form) and kumarines in lipid base" - full complite answer from useful dialog
2) If it is "big commercial secret" - no problem. You will have good money from patents - and you job problem => only you commercial problem

Hi,

Try methanol/dichloromethane (70/30) or 50/50. It often works for me

Cheers

Ralph

can any body recomend procedure for extraction ointment or cream for gc-ms or lc-ms?

Do you want to extract it or dissolve it. If the first then you need a solvent that dissolves the analyte, but not the matrix, if the second than a solvent that dissolves both. If you just dissolve it you may need to do a clean up to get rid of components that might crud up your instruments.

Peter

Hi,

Just to expand on my previous reply.

As Peter correctly pointed out it depends on your target analyte. I used the methanol/dichloromethane mix based on on Restek's "Magic mix" because it can dissolve aqueous/organic samples. Since creams are usually oil in water or water in oil emulsions often based on, but not limited to, (wow I sound like a patent) low melting point paraffin, cetyl/stearyl alcohol, wax esters, dimethicone or other silicones it worked very well to dissolve the sample. Depending on the target analyte and it's solubility I would then play around ( pre- GLP ) by adding more water or methanol. This would then form 2 phases with the analyte hopefully in one of the phases with the least extra crud.

I must admit that in later years with GCMS/SIM I did become a bit lazy about what I put on the column

If you could tell us what your target analyte is then CPG might be able to help you more easily

Regards

Ralph

Hi, please help me.

I have a problem with how to separate active ingredient(prefer soluble in methanol) from mixture of orange oil and non-ionic surfactants. Since the orange oil make baseline noise at the same time as retention time of active ingredient, which interrupt peak area calculation. Thus, I want to reduce the interfere by separating oil from sample, but I don't know how to. Please help me!

Thank you

Nattawee

I have a problem with how to separate active ingredient(prefer soluble in methanol) from mixture of orange oil and non-ionic surfactants. Since the orange oil make baseline noise at the same time as retention time of active ingredient, which interrupt peak area calculation. Thus, I want to reduce the interfere by separating oil from sample, but I don't know how to.

If you really need help, detail
(1) what is your active ingredient
(2) are you using GC or HPLC, and/or do you have access to both? If HPLC, what detectors does your company have?

Hi

My active ingredient is ellagic acid, and I'm using HPLC with uv-detector.

Thankyou for your kindness

nattawee