A new approach for the determination of selected alkaloids (nicotine a
nd nornicotine) and sugars (fructose, glucose, sucrose, xylose and mal
tose) in tobacco is described. The analytical method is based on the s
imultaneous extraction of alkaloids and sugars from tobacco samples wi
th an acetic acid-methanol solution, followed by parallel isolation of
target analytes from extract aliquots by solid-phase extraction, usin
g octadecyl silica (C-18) for alkaloids and aminopropyl silica (NH2) f
or sugars. The extracts were analysed by liquid chromatography using U
V absorbance detection for alkaloids and refractive index detection fo
r sugars. The recoveries from spiked extracts were high and reproducib
le, ranging from 94 to 97% for alkaloids, and from 62 to 97% for sugar
s, at concentration levels that were as expected following extraction
from average quality tobacco material. The method was tested in the an
alysis of a Virginia tobacco sample. The results obtained for individu
al compounds were in good agreement with those obtained by spectroscop
ic measurements of total alkaloids and total sugars in the same tobacc
o sample. (C) 1997 Elsevier Science B.V.