Ethanol in wines was determined by flow injection analysis with an amp
erometric detector using an oxidized nickel wire. Solid-phase extracti
on with a strong anion exchanger was used to remove interferences such
as organic acids from the matrix, and the residue of the extraction w
as injected directly into the FIA system. The recoveries of ethanol fr
om wines spiked with standards ranged from 101 % to 103 %. The respons
e of the nickel electrode to ethanol is dependent on the applied poten
tial and the pH of the carrier. The optimal conditions for the detecti
on of ethanol were an applied potential of +0.60 V (vs. Ag/AgCl) in a
carrier of 100 mM sodium hydroxide solution. The electrode exhibited a
linear response from 10(-5) to 10(-3) M, with a detection limit of 1
x 10(-6) M. The method was demonstrated by the determination of ethano
l in wines.