Highly Sensitive Determination of Cinchonine in Serum Samples by Electrochemical Luminescence Method

KeyWord:electrochemiluminescence  cinchonine  Ru£¨bpy£©2+3  serum

Abstract:

      In this paper,the eletrochemical luminescence£¨ECL£© behaviors of cinchonine-Ru£¨bpy£©2+3 system was studied with the gold electrode as working electrode.ECL intensity of Ru£¨bpy£©2+3 could be enhanced significantly in the presence of cinchonine.Based on this fact,a high sensitivity ECL method was established for the determination of cinchonine at gold electrode.Some detection conditions such as concentration and pH value of buffer solution,concentration of Ru£¨bpy£©2+3 and voltage of photomultiplier tube were optimized.In 12 mmol/L boric acid-borax buffer solution£¨pH 9.0£©,the ECL peak counts increased linearly with concentration of cinchonine in the range of 3.0¡Á10-9-6.0¡Á10-6 mol/L.The detection limit£¨S/N=3£©for cinchonine was 1.76¡Á10-10 mol/L.The method was applied in the determination of cinchonine in serum with recoveries of 102.1%-109.5%.