| Chemiluminescene (CL) permits an increase of sensitivity in a detector, and therefore an attainment of a large signal-to-noise ratio (S/N). In addition, there are more advantages in CL detection, such as wide dynamic range, simple instrumentation, versatility of use and the easy automation. Based on its advantages, here we combined the chemiluminescene with flow injection (FI) technique in analysis. The main contents are shown as follows:1. The main purpose of this study was to develop an inexpensive, simple, rapid and sensitive CL method for the determination of glutamine (Gin) using a FI system. Gin was found to strongly inhibit the CL signal of the luminol-H2O2-CuSO4 system in Na2B4O7 solution. A new FI-CL method was developed for the determination of Gin based on which. Parameters affecting the reproducibility and CL detection were optimized systematically. Under the optimized conditions, the corresponding linear regression equation is established over the range of 5.0×10-7-2.5×10-6 mol/L with the detection limit of 1.8×10-8 mol/L. The relative standard deviation (RSD) was found to be 1.8% for 11 replicate determinations of 1.5×10-6 mol/L Gin. The proposed method has been satisfactorily applied for the determination of Gin in real samples (Marzulene-s granules) with recoveries in the range of 98.7% to 108.6%. The possible mechanism of this inhibitory CL was studied by fluorescence spectrophotometer and UV-vis spectrophotometer.2. It was found that 20 amino acids could inhibit the intensity of the luminol-H2O2-CuSO4 CL system. Using this character, a rapid and sensitive method for the determination of 20 amino acids was developed with FI coupled with CL detection. Under the optimal conditions,20 amino acids were detected with satisfactory results. The detection limits were in the range of 4.5×10-7 to 4.3×10-10 mol/L, and the RSDs were less than 3.2%. The proposed method was successfully applied to drug analysis. The possible mechanism was also discussed.3. A novel, rapid and sensitive method was described for the determination of epinephrine (EP) using FI coupled with CL detection, which based on EP enhanced the weak CL emission of luminol-KIO4 system in NaOH solution. Parameters affecting the CL intensity and reproducibility were optimized systematically. Under the optimized experiment conditions, the net CL intensity was proportional to the concentration of EP in the range of 5.0×10-8 to 1.5×10-6 mol/L with the detection limit of 1.9×10-9 mol/L. The RSD was found to be 0.7% for 13 replicate determinations of 3.0×10-7 mol/L EP. The applicability of the proposed method was illustrated in the determination of EP in pharmaceutical preparation. The recoveries of EP at different levels in EP hydrochloride injection were between 95.4 and 104.7%. One assay procedure takes only 27 s, and the sampling rate was calculated about to be 130 samples/h. The possible mechanism of the enhanced CL intensity was studied by examining CL spectra and UV-vis spectra.4. A novel, sensitive and selective method to detect hemoglobin (Hb) by FI coupled with CL detection was described, which based on Hb enhancing effect on weak CL system of luminol-hydrazine in NaOH solution. Parameters affecting the reproducibility and CL detection were optimized systematically. Under the optimized conditions, the net CL intensity versus Hb concentration was linear in the range of 5.0×10-9 to 6.0×10-5 g/mL with the detection limit of 5.8×10-10 g/mL (approximately 9.0×10-12 mol/L) calculated as proposed by IUPAC. The RSD for 8 replicate determinations of 5.0×10-7, 7.0×10-6 and 4.0×10-5 g/mL Hb were 1.6,0.7 and 1.5%, respectively. The proposed method has been satisfactorily applied for the determination of Hb in human blood and serum with satisfactory recoveries in the range of 83.0 to 101.0%. The possible mechanism of this enhancement CL was studied by fluorescence spectrophotometer and UV-vis spectrophotometer.
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