Abstract: SudanⅡ shows a sensitive reduction peak at -0.85 V on its linear sweep polarogram in a buffer solution of Britton-Robinson(BR)(pH8.0) with alcohol selected as a co-solvent to dissolve it. The peak current is linearly proportional to the concentration of sudanⅡin the range of 1×10-8 mol/L to 1.6×10-7 mol/L with coefficient of 0.9978. The detection limit is 1.6×10-9 mol/L. This method was applied to the determination of sudanⅡ in chili powder. The recoveries are 88.8% to 103.2%.

Key words: sudanⅡ, single-sweep polarography, chili powder