Based on the fact that 6-propy-2-thiouracile(PTU) could strongly enhance the electrochemiluminescence(ECL) of tris(2,2’-bipyridine) ruthenium(Ⅱ)(Ru(bpy)2+3),a new flow injection analysis method with a homemade electrochemiluminescence(FI-ECL) detector was proposed for the first time.The experimental parameters those may influence the ECL intensity of the Ru(bpy)2+3/PTU system(such as voltage signal mode and applied potential,pH of buffer solution,flow rate of the carrier solution,and concentration of Ru(bpy)2+3solution ) were investigated.The optimum conditions for the FI-ECL detection of PTU were obtained and the possible mechanism of the ECL system was suggested.The results showed that in 0.1 mol?L-1 pH 12.0 H3PO4-NaOH buffer solution,when the carrier solution’s flow rate was setted at 1.5 mL?min-1,the strongest ECL intensity enhancement could be realized at potential of +1.50 V in the present of 1.0×10-4 mol/L Ru(bpy)2+3.Under this optimal condition,the linear range of PTU was 2.0×10-7-1.0×10-4 mol/L with a correlation coefficient of 0.998 6 and a detection limit(S/N=3) of 1.3×10-8 mol/L.The relative standard deviation(RSD,n=3) for 1.0×10-6 mol/L PTU standard solution was 1.2%.The method was simple,rapid and sensitive,and was successfully applied in the determination of PTU in spiked animal feeds. |