I have a query. Please let me explain, I have various fatty acid methyl ester calibration curves between the range of 50-500 ppm. Now I have some oil samples that I am studying. In order to study those, I am derivatizing those using BF3 in Methanol. For derivatizing, my sample involves 100 mg oil + 0.5 ml BF3 in Methnaol (reagent) +1 ml of Hexane (as solvent). Now at the end of derivatization, the hexane layer which I will be injecting in GC for analysis, how do I get that concentration within the calibration range, that is 50-500 ppm.
Please can someone help me understand how make that sample.
Dear Sailee Nagpurkar ,
there is too little information in Your query... Firstly, You should think about matrix effect. If Your matrix does not influence into detector signal, You can use external calibration (in solvent) - I suppose from Your query that You made it. In some cases it is appropriate. However, If You use external calibration, recoveries should be taken into account which affect concentrations. I do not know the recoveries of Your extratction, because You extract analytes into hexane layer. If matrix-match calibration is used, the influence of ME, recoveries and dilution concerning derivatization is reduced. Think about this issue.
Please let me know more details on Your sample preparation procedure.
Best regards,
Mateusz
I have experience regarding the fatty acid analysis in fish and fishery products and seaweeds. I followed the Bligh and dyer method for preparing the FAME. In this method clearly mention that the way of derivatization. And also I used the heptadecanoic acid (C17:0) as Internal standard (IS). The concentration of the IS was known. After taking the Chromatogram we can take the peak area or height. In my case highest recovery obtained from peak area. Then we have the area ratio of the IS and sample. The concentration of the IS was known. We can easily calculate the unknown concentration of the sample.
- Badges
- Science topic