Matrix solid phase dispersion (MSPD) was used in the determination
of the organophosphorus (OP) pesticides diazinon and ethion in pistachio
nuts. Ground nut samples were blended with C18 adsorbent and packed
into a column on top of lanthanum silicate ion exchanger as a co-column.
After washing the column with hexane, the purified residues were extracted
with dichloromethane–ethyl acetate (1 + 1) before TLC analysis [8].
Additional sample preparation methods are described in some of
the applications cited in the sections below