What is the best way to prepare vitamin A (retinyl palmitate and retinyl acetate) and vitamin E (alpha tocopherol) standards for vitamin analysis?

Paidamoyo Mataranyika @Paidamoyo-Mataranyika-2

06 March 2019 1 4K Report

I am analyzing vitamin content in legumes and I cannot obtain consistent retention times of the respective standards using diethyl ether as a solvent and acetonitrile: methanol (90:10) mobile phase. Can anyone please suggest what I may be doing wrong or the best way to prepare the standards?

Maria Stacewicz-Sapuntzakis

Dissolve in ethanol and calculate concentration from peak absorbance. Confirm purity by HPLC.

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