Fractionation of cis/trans FAMEs in popcorn oil
CONDITIONS
sample preparation
SPE (Solid Phase Extraction)
sample/matrix
1 g of popcorn oil FAME′s in Hexane
SPE tube/cartridge
Discovery Ag-Ion, 750 mg/6 mL (54225-U)
condition
4 mL acetone and 4 mL hexane
sample addition
1 mL of the hexane FAME extract
elution
6 mL hexane:acetone (96:4, v/v) followed by 4 mL hexane:acetone (90:10, v/v)
column
SP-2560, 75 m x 0.18mm I.D., 0.14 μm (23348-U)
oven
180 °C isothermal
inj. temp.
220 °C
detector
FID, 220 °C
carrier gas
hydrogen, 40 cm/sec. at 180 °C
injection
(0.5 μL, 100:1 split)
liner
0.5 μL, 100:1 split
Descripción
Preparation Note
Sample pretreatment: A 1 g sample of popcorn oil was scraped from the inside of a popped microwave oven popcorn bag and mixed with 8 mL deionized water (DI) and 4 mL petroleum ether, centrifuged to remove particulates. The ether layer (upper layer) was collected. This petroleum ether extraction step was repeated four times. The upper ether layers were combined, evaporated, and reconstituted in 16 mL toluene. A 1 mL aliquot was transferred to conical reaction vial and 2 mL 7% boron triflluoride in methanol were added. The reaction was incubated at 80 °C for 15 minutes using a heating block, then cooled to room temperature. 1 mL DI water was added and FAMEs were extracted twice using 1 mL hexane each time. The upper hexane layers were combined into a fresh vial, evaporated, and reconstituted in 5 mL hexane and 50 mg anhydrous sodium sulfate.
Analysis Note
Discovery Ag-Ion operates by argentation chromatography which is a powerful analytical and sample prep technique for the separation or fractionation of cis and trans geometric and positional fatty acid (FA), fatty acid methyl ester (FAME), diacylglycerol (DAG) and triacylglycerol (TAG) isomers. Discovery Ag-Ion SPE is shown in this application to separate FAMEs from an edible oil sample.
Legal Information
Discovery is a registered trademark of Merck KGaA, Darmstadt, Germany
SP is a registered trademark of Sigma-Aldrich Co. LLC