Chromatography Forum

hi ,
i have cream sample and i want to know if it's combined by plant oil and its percentage if present , i have HPLC knaur and column c18 , RI & UV detectors ,is this sufficient to determine triglycerides and how i can prepare sample
thanks

You ought to be able to do trigylcerides by RPHPLC with RI detection. I don't see how you will see a difference between
animal fat and vegetable oils though. What samples do you have?

thanks , you suggest a specif mobile phase , my sample is Cream cheese and i want to know if it's contain plant oil or not

Both reversed-phase (RP) and normal phase (NP) or HILIC columns can be used for analysis of triglyceride. A RP column elutes triglceride based on hydrophobicity. On a HILIC column, the elution order is usuallt reversed - the more hydrophobic the analyte, the shorter the retention. The mobile phase usally contains high organoc solvent. The detection method can be CAD, ELSD, MS, or RI. Attached link provides examples of analysis of glycerides on Acclaim C18 and Acclaim HILIC-10 (Thermo Fisher Scientific). If you want to obtain more detailed "fingerprint" type profile, the Acclaim C30 can be a good choice.

HILIC: http://www.dionex.com/en-us/images/pdf- ... LIC-10.pdf
RP: http://www.dionex.com/en-us/webdocs/738 ... 266-02.pdf
Acclaim C30: http://www.dionex.com/en-us/webdocs/110 ... PN2776.pdf

We've done intact triglycerides by both RP HPLC with ELSD, and by high-temperature capillary GC (specialty columns).

But for what you are describing as your focus and goal, I think you want to analyze the fatty acids of those triglycerides (make into fatty acid methyl esters) by GC using a cyanopropyl silicone column. If you don't have GC, you have just a partial lab.

We've done intact triglycerides by both RP HPLC with ELSD, and by high-temperature capillary GC (specialty columns).

But for what you are describing as your focus and goal, I think you want to analyze the fatty acids of those triglycerides (make into fatty acid methyl esters) by GC using a cyanopropyl silicone column. If you don't have GC, you have just a partial lab.

hi, any idea is there a different of the results obtained with LC and GC?

We've done intact triglycerides by both RP HPLC with ELSD, and by high-temperature capillary GC (specialty columns).

But for what you are describing as your focus and goal, I think you want to analyze the fatty acids of those triglycerides (make into fatty acid methyl esters) by GC using a cyanopropyl silicone column. If you don't have GC, you have just a partial lab.

hi, any idea is there a different of the results obtained with LC and GC?

Recovery of a triglyceride from an RP column, particularly a C18, likely will be less than quantitative

from where are your samples?
is it a biodiesel project? algue? acid degradations?
do you have any idea on the characteristics of the compounds type you will get?
less or more saturated? any chance of some of them being with a polar group in it?

from where are your samples?
is it a biodiesel project? algue? acid degradations?
do you have any idea on the characteristics of the compounds type you will get?
less or more saturated? any chance of some of them being with a polar group in it?

my samples from a researcher in the field of dairy technology
it's cheese samples manufactured by the researcher for his research
yes i have
more saturated

my guess is you will have then more sterio-isomers and so the c28-30 columns or maybe a cholester column will be better.
ELSD or CAD are best as detector for you,
RI will not let you use a gradient, and UV will probably not work unless you use derivatisation. you will need something above 250 nm preferably so that you have less problems from the solvents that you will use.
a good starting point might be the application in the C-30 brochure from XL, at page 4-5 pictures 7-9