An Al/Ag galvanic cell was investigated and integrated in flow injection electrochemiluminescence analysis system (FI-GCECL). The proposed method was applied to the determination of isoniazid content in isoniazid tablets. A galvanic cell was made from pure Ag and Al, and it supplied a stable potential output in a flow of sodium hydroxide solution. The potential variation in about 1300 to 560 mV range could be obtained by varying the concentration of sodium hydroxide or by employing different alkaline solution in the flow. When the potential output of the described cell was 1168 mV while the sodium hydroxide concentration was 5.0*10~(-4) mol·L~(-1) and luminol concentration was 5.0(10-6 mol·L1, the presence of isoniazid could greatly enhance the electrochemiluminescence of luminol in the vicinity of platinum anode surface. Isoniazid contents in three kinds of isoniazid tablets were determined and the analysis results agreed well with those from official method. This analysis application proved to be a practical use for the present method.

Key words: ELECTROLUMINESCENCE, FLOW INJECTION ANALYSIS, ISONIAZIDUM, LUMINOL