| In recent years, as one of the powerful luminescence analytical techniques, Electrogenerated Chemiluminescence (ECL) analysis has been paid much attention in analytical science since this technique not only retains the advantage of the conventional Chemiluminescence (CL) analysis, but also offers some advantages over more conventional CL. Firstly, the ECL reaction can be easily regulated and manipulated by the applied potential. Secondly, the ECL emission is concentrated close to the vicinity of the electrode, which can be shaped and accurately positioned in relation to the optical measurement system for maximum sensitivity. Thirdly, the analyte can be in-situ modified electrochemically to form the corresponding CL active specie without the chemical contamination due to the addition of the necessary reactants in the corresponding CL reactions. Thus, ECL analysis, compared to CL analysis, offered the more alternative potentials to regulate the ECL reaction for analytical purpose. Based on these considerations, we focused our interest on the improvement of the electrogenerated Chemiluminescence (ECL) analysis with the use of both the flow-injection technique and the chemically modified electrode technique.In the first part of this paper, By designing three different kinds of the flow-through electrolytic cells and the use of the constant current or constant potential electrolytic technique, it was found that the ECL reaction means and the activity of the electrogenerated reagents could be controlled and further improved, respectively. In this case, by using these flow-through ECL reactors, some novel ECL methods for quinine, tetracyclines, captopril and isoniazd etc, have been developed, respectively.In the second part of this paper, we focused our interesting on the combinationof the chemically modified electrodes technique with ECL analysis to improve the analytical performances of the original ECL methods. It was found that bentonite , acetate celluose, and platinum oxide-based chemically modified electrodes offered the good ECL analytical performances. The major content was described as follows:1. The investigation of the ECL reaction ways and the ECL reagent activity on its analytical performances(1) Flow Injection Chemiluminescence Determination of Quinine Using Mn3+ AsThe OxidantBy the use of a flow-through electrolytic cell and a flow-injection system, Mn3+ can be on-line obtained quantitatively by galvanostatic method. At the same time, It was found that the quinine has a stronger sensitizing effect for the weak CL signal produced by the reaction of sulphite with Mn3+ in sulpuric acid medium. Based on this observations, a new, rapid and simple flow injection CL method for the determination of quinine is proposed and which allows determination of quinine concentration in the 0.10-100.0umol/L range with a detection limit of 0.040umol/L and the possible CL reaction scheme is discussed.(2) Flow-injection Chemiluminescence Determination Of Tetraceyclines WithIn-situ Electrogenerated Br2 As the OxidantBy designing a novel flow-through electrolytic cell, Br2 was produced in the near surface of the platinum electrode with electrochemical oxidizing acidic KBr. Then it was found that the fast and weak Chemiluminescence (CL) signal, produced by the chemical reaction of electrogenerated Br2 with H2O2, was greatly enhanced by tetraceyclines. Based on these observations, a new, sensitive and simple Electrogenerated Chemiluminescence (ECL) method for the determination of tetracyclines was developed in this paper. Under the optimum experimental conditions, the calibration curves are linear over the range 3.0x10-8 - 5.0x10-5 g/mL for tetracycline, 2.0x10-7 - 2.4x10-5 g/mL for oxytetracycline and 1.0x10-7 -5.0x10-5 g/mL for chortetracycline. The limits of detection (S/N =3) are 1.0x10-8 g/mL for tetracycline, 7.0x10-8 g/mL for oxytetracycline and 1.5x10-7 g/mL for chortetracycline. For the analysis of 5.0x10-7 g/mL tetracyclines, the relative standard deviation was less than 5%. The pro...
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