【摘要】 基于Fe(Ⅲ )氧化SO2 - 3生成Fe(Ⅱ )的反应和鲁米诺 O2 Fe(Ⅱ )化学发光反应相偶合 ,建立了流动注射化学发光测定SO2 - 3的方法 ,方法检出限为 3× 10 - 8g·ml- 1,RSD为 2 % ,方法用于食品中SO2 - 3的测定 ,结果满意更多还原

【Abstract】 It is found that the redox reaction between Fe(Ⅲ) and SO 2- 3 can be coupled with the chemiluminescence reaction among luminol, oxygen and Fe(Ⅱ), and mcroamounts of SO 2- 3 can thus be determined indirectly. A flow injection analytical process is proposed with a schematic diagram shown in Fig 1. The sample solution is mixed first with a solution of ferric ion of definite concentration and a stoichiometric amount of Fe(Ⅱ) is produced through the reduction of Fe(Ⅲ) by SO 2- 3. Then a definite amount of alkaline luminol solution at pH 11.0 is injected to react with the Fe(Ⅱ) and dissolved oxygen. The chemiluminescence produced is detected by the photoamplifier, and the peak heights of the luminescence intensity is recorded. The detection limit is found to be 3×10 -8 g·ml -1 . RSD is found to be 2% at the concentration level of 8×10 -7 g·ml -1 ( n =11). The proposed method has been used in the determination of SO 2- 3 in food with satisfactory results.更多还原