Modification of the rapid high-performance liquid chromatographic method for the determination of potato glycoalkaloids

Abstract

A comprehensive evaluation of Carman et al.’s (1984) rapid high-performance liquid chromatographic analysis of potato glycoalkaloids has led to some modifications. Heptanesulfonic acid extracts ap-proximately 81% of the glycoalkaloids from fresh tubers when compared to the accepted organic solvent methanol/chloroform/acetic acid (67:33:1). Glycoalkaloids in dehydrated potatoes are still best extracted with tetrahydrofuran/water/acetonitrile/glacial acetic acid (50:30:20:1). Samples extracted with hep-tanesulfonic acid must be cleaned up within 3–4 h after extraction. Those extracted in organic solvents are stable indefinitely. C18 Sep-Pak’s can be used six times before they are not effective. Aceto-nitrile/water (50:50) elutes the glycoalkaloids more effectively from the C18 Sep-Pak than aceto-nitrile/buffer (50:50). Glycoalkaloid separations on an amino column can be cleaned up on C18 Sep-Pak’s. © 1986, American Chemical Society. All rights reserved.