| Chemiluminescence has become one of the focus in the area of analytical chemistry due to its advantages such as higher sensitivity, wider linear range, simpler instrumentation, versatility of use and the easy automation. Based on its merits, here we combined the detection method with flow injection (FI) technique and capillary electrophoresis (CE) technique, and discussed its application for environmental and biological samples analysis. The main contents are shown as follows: (1) A new method for the determination of lead in gasoline was developed by flow injection-chemiluminescence method based on the fact that Lead(Ⅱ)catalyze the luminol-potassium ferricyanide oxidation reaction. The optimum conditions for the determination were investigated. Under the optimum conditions, the CL intensity is linear with Pb(Ⅱ)concentration in the range of 1.0×10-6～1.0×10-4mol/L,and the detection limit is 3.8×10-7mol/L. The RSD is 3.5% for 11 measurements of 1.0×10-5mol/L lead standard solution. (2) Indirect chemiluminescence(ICL)detection for capillary electrophoresis (CE) of monoamines and catechol using luminol-K3[Fe(CN)6] system was described. A strong and stable background chemiluminescence (CL) signal can be generated by luminol-K3[Fe(CN)6] reaction. Based on the principle of that some phenolic compounds may be oxidized in the presence of K3[Fe(CN)6], quenching effect of catecholamines for luminol-K3[Fe(CN)6] CL reaction results in a quantifiable decrease in the background signal. The conditions for CE separation and the CL detection for four standard catecholamines were systematically investigated using a homemade CE-ICL system. Under the optimum conditions, the detection limits of dopamine,epinephrine,norepinephrine and catechol were determined to be 0.33μM,1.8μM,2.4μM,0.12μM,respectively. It also has been successfully applied to analyze three pharmaceutical samples and seven human urine samples. Our data demonstrated this method would be a powerful tool for clinical analysis, because the best advantage of this method was the selectivity improved markedly. (3) Based on the fact that some amino acids and proteins can enhance the luminol-potassium ferricyanide reaction in basic medium,capillary electrophoresis was used in combination with on-line chemiluminescence detection for the simultaneous separation and determination of L-Arginine and Pepsin. The chemiluminescence reaction conditions, such as reaction reagents concentrations, pH of potassium ferricyanide solution, and the electrophoresis conditions were examined for acquiring good sensitivity and good separation. Under the optimum conditions, the detection limits of 1.3×10-4M for L-Arginine and 7.1×10-7M for Pepsin were determined. The most advantage of this presented method is that the tedious labeling procedure is not required. Moreover, the CL system is simpler than that presented before. The prospect of this developed method for determination of free labeled amino acids and proteins in biological samples was also discussed in detail.
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