| Chemiluminescene(CL) is highly sensitive. It needs no exciting light source, and thus isnot accompanied with any scattering light from it. This permits an increase of sensitivity ina detector, and therefore an attainment of a large signal-to-noise ratio (S/N). Besides, thereare more advantages in CL detection, such as wide dynamic range, simple instrumentation,versatility of use and the easy automation. The method that is one of the studied focus in thearea of analytical chemistry today has gained wide use in environmental, pharmaceuticaland biological analysis. Based on its advantages, here we combined the detection method with mauley injectiontechnique, flow injection (FI) technique and capillary electrophoresis(CE) technique, furtherto extend its application in environmental analysis. The main contents are shown as follows: (1)Anovel, simple analytical procedure for determination of Chromium(Ⅲ) in environmental samples with photodiode detector is presented successfully, which isbased on the fact that chromium(Ⅲ) can catalyze the luminol oxidation reaction withhydrogen peroxide in basic medium using potassium bromide as an enhancer .The singleanalyzing time is less than 1 min. The linear range of calibration curve was 5.0×10-8g/ml～5.0×10-4g/ml . The detection limit was 5.0×10-8g/ml . The RSD was less than 5.0%(n=6).And the detecting equipment is simple and cheap. The method has been applied to thedetermination of Cr(Ⅲ) in environmental samples successfully . (2) Based on the chemiluminescent reaction of luminol-H2O2-Cr3+ system, lightemission caused by luminol-H2O2-Cr3+system was detected by the photodiode, and itsintensity caused by the appearance of Cr3+after samples digestion was proportional to thechemical oxygen demand. A low cost chemiluminescence detector with a photodiodeinstead of photo-multiplier tube (PMT) was developed for environmental monitoring ofwater quality. The linear range was 2.1～600mg/L, r=0.9987; recovery rate was between90% and 110% and RSD was lower than 5.0%(n=6). The experimental results show that thissuggested method uses an instrument simpler and cheaper than the previous ones for thesame purpose. The data obtained by the present method were fairly in good agreement withthose obtained by the standard reflux titrimetric method. It has been applied to determinereal samples with satisfactory results. If combined the present method with microwave IIIdigestion and flow injection, a novel way to can be pioneered to develop a fast, accurate andsimple COD automation detection instrument. (3) PAR showed intensive chemiluminescence (CL) when it was added to thelumonol-K3Fe(CN)6 system in the NaOH basic medium. The main factors that affected theCL reaction were examined. A new analytical method for determination of schiff base withAzosubstituted groups was proposed. The linear relationship between the intensity of CLand the concentration of PAR was in the range of 1.0×10-5 mol/L～1.0×10-7 mol/L ,andthe detection of limit was 5.7×10-8mol/L,the RSD was 2.7%.Beacuse PAR is a commonlychelating agent in the analysis of many metal ions, the method has also been used todetermine several metal ions according to the decrease of relative chemiluminescenceintensity of PAR and the detection of limit of these metal ions were acquired, so the studyalso afforded a new prospect for the analysis of metal ions using chromatography orcapillary electrophoresis. (4) According to the fact that potassium ferricyanide hydrolyzes to form KCN, andCu2+ reacts with luminol forming Cu (CN)2 to generate luminescence. A new method for -the determination of Cu2+ in environmental samples was studied. The linear range was 1.0×10-7 mol/L～5.0 ×10-9 mol/L ,the limited detection was 8.06×10-10 mol/L ,the RSD was3.0%(n=6). The acquired limited detection was corresponded to that of KCN-Luminolsystem. But it is well know...
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