| Though with high efficiency of separation, high performance liquid chromatography (HPLC) has a low sensitivity due to its detector, or needs derivation as pretreatment. Chemiluminescence, as a method of detection, has a wide linearity, high sensitivity, but suffers from interference. The chromatography separation with CL detection can make up their own drawbacks, and has been widely applied in the area of environment, clinical diagnosis, pharmacy, biochemistry and so on.Ion chromatography (IC), as a branch of HPLC, has also made great success in the above areas. But the chromatographic instrument which is operated under high pressure condition is too expensive to afford, and lacks of a sensitive detection method at the same time. The low-pressure ion chromatography (LPIC), which is made up with special packing material can use common peristaltic pump instead of high pressure pump, thus reduces the cost of the instrument and avoids of jam and leak under high pressure operation.This study mainly focuses on the anion measurement by LPIC separation with CL detection which consists of following two parts:The first part is a review concerning the mechanism of LPIC and its application, CL as a way of detection with other novel methods, such as FIA, CE, μ-TAS, especially with LC. The second part is research reports including some anions determined by LPIC-CL as follows: 1. Sulfite Determination By Low Pressure Ion Chromatography with Chemiluminescence Sensitized byHypoxanthineSulfite concentration is detected by low pressure ion chromatography (LPIC) with chemiluminescence due to the fact that hypoxanthine can enhance the depression effect of sulfite on luminol-KMnO4 chemiluminescence reaction. The liner range of sulfite concentration under optimal conditions is 5×10-8-4.8×10-6mol·L-1(r=0.9977) with a detection limit of 1.6×10-8mol·L-1, and RSD is 3.25% by detecting 5×10-7 mol·L-1 for five times. This simple, rapid and sensitive method is successfully applied to sulfitedetermination in food samples.2. Determination of Cr(VI) by Low Pressure Ion Chromatography(LPIC) with Coupled Chemiluminescence Sensitized by Tween-20A method for the determination of Cr(VI) is developed. Cr(VI) is separated by low pressure ion chromatography, and then reacts with K4Fe(CN)6 to form K3Fe(CN)6. The product reacts further with luminol to produce chemiluminescence, which is greatly enhanced by Tween-20. Under optimum conditions, the concentration of Cr(VI) is proportional to chemiluminescence intensity in the range of 2.8xl0'9-1.0xl0"6g-mL"1(r=0.9982), with a detection limit of 9.3><1 O'^g-mL'^a). This method can be applied to the determination of Cr(VI) in river water and the result agrees well with standard method.3. On Line Measurement of Cr(VI) by LPIC with Post Column Coupled CL Enhanced by FluoresceinThe online separation and determination of Cr(VI) by LPIC with post column CL is investigated for the first time. After has been eluted by NaNO3, Cr(VI) reacts with K4Fe(CN)6 to form K3Fe(CN)6 that can react with luminol to produce chemiluminescence. By the two coupled reactions, Cr(VI) is able to be measured with sensitization by fluorescein. The linear range of Cr(VI) is in 6.0><10"9-2.8xl0"7g-mL"1(r=0.9964), with a detection limit of 2.0x10'9g-mL"1(3o), and RSD is 1.24% by measuring 1.6xlO'7g-mL"' for five times. This method is applied to Cr(VI) measurement in river, and agrees well with standard method.4. On Line Rapid Determination of I" by LPIC with CL DetectionBased on the phenomenon that I"-KmnO4-HCHO will react to produce strong chemiluminescence in acid medium, I" is determined by LPIC with CL. Under best conditions, the linear is 2xlO"M.5xlO'4g-mL"1 with a detection limit of 6.6xlO7g-mL1.
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