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Chinese Chemical Letters 2010年第6期21卷 712-715页

作者： Saima Jadoon Amir Waseem Mohammad Yaqoob Abdul Nabi Department of Chemistry University of BalochistanQuettaPakistan

A simple and sensitive flow injection spectrophotometric method is reported for the determination of vitamin E using potassium ferricyanide-Fe(Ⅲ) detection *** the presence of vitamin E,Fe(Ⅲ)/ferricyanide *** in situ reduced ions are then reacted with unreduced portion of ferricyanide/Fe(Ⅲ) to make soluble Prussian blue,which is monitored at absorption wavelength of 735 *** calibration graph was obtained in the concentration range of 0.1-40μg mL^(-1).The relative standard deviations (n=4) were in the range of 1.1-3.6%,with limits of detection(3 s blank) of 0.04μg mL^(-1).The proposed method allowed 12 injections h^(-1).The method is applied to determine vitamin E in pharmaceuticals,infant milk and blood serum samples using hexane extraction with the recoveries in the range of 93±3 to 97.5±4%.The method is validated using certified reference materials SRM 968c for blood serum samples.

关键词： flow injection Spectrophotometry Vitamin E Prussian blue Fe(III) Ferricyanide Pharmaceuticals Blood serum

flow injection Chemiluminescence Analysis of Low Level Concentration of Hydrazine

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Chinese Chemical Letters 2001年第9期12卷 799-802页

作者： Zheng Hua SONG Lin WANG Ji Hong Lü Tie Zhu ZHAO Department of Chemistry Northwest UniversityXi’an 710069 Xi’an Modern Chemistry Research Institute Xi’an 710060

Combined with flow-injection (FI) technology, a simple chemiluminescence (CL) method was developed for hydrazine determination in this paper. It was found that hydrazine could greatly decrease the strong CL signal produced by the reaction between luminol and hexacyanoferrate (III) in alkaline medium. The decreased CL intensity was linear with hydrazine concentration in the range of 5.0×10-9 g·mL-1 to 4.0×10-5 g·mL-1, and the limit of detection was 2.0×10-9 g·mL-1 (3σ) with a relative standard deviation of 2.4~4.1% (n=5).

关键词： Hydrazine flow injection chemiluminescence

flow injection Chemiluminescence Determination of Puerarin in Pharmaceutical Preparations Using Eosin Y-Fenton System

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Chinese Journal of Chemistry 2011年第6期29卷 1261-1267页

作者： Cai, Zhuo Zhang, Xian Lu, Dengfeng Gan, Jingni College of Chemistry and Chemical Engineering Guangxi University Nanning Guangxi 530004 China

A novel chemiluminescence （CL） system was established for the determination of puerarin in pharmaceutical preparations. It was shown that a strong CL signal was observed when Eosin Y reacted with the hydroxyl radicals which were generated from Fenton reagent in acidic medium. The CL intensity was decreased significantly when puerarin was added to the reaction system and partially scavenged the hydroxyl radicals in the solution. The extent of decrease in the CL intensity had a good stoichiometrical relationship with puerarin concentration. Based on this, a new method for the determination of puerarin using a flow injection chemiluminescence technique was developed. The experimental parameters that affected the CL intensity were optimized. Under the optimal conditions, the linear range for puerarin concentration was 8.0 × 10^-8--2.0 × 10^-6 mol/L （R = 0.9982） with a detection limit of 7.5 × 10^-9 mol/L （S/N= 3） and the relative standard deviation was method was applied to the determination of puerarin in a 1.7% for 4.0× 10^-7 mol/L puerarin （n= 11）. The proposed puerarin injection with satisfactory results.

关键词： flow injection chemiluminescence Eosin Y puerarin hydroxyl radical

Determination　of　Trace　Non　Rare　Earth　Elements　in　High　Purity　Rare　Earth　Oxides　by　ICP－AES　with　Microcolumn　Preconcentration　in　a　flow　injection　System

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Journal of Rare Earths 1995年第2期13卷 119-124页

作者：吉红念廖振环江祖成谢金娥 Wuhan Univ Wuhan China

A new method for the determination of trace non-rare earth elements in high purity rare earth oxides by ICP-AES with preconcentration on an active carbon-silica gel microcolumn in a flow injection system is described in this paper. Experimental parameters such as pH, flow rate,reagent concentration,length of reaction coil,eluent acidity,etc. were optimized. In the buffer solution of NH3. H2O/NH4Cl at pH 4. 6,Al,Cr,Cu,Fe, Pb, V and Zn can be preconcentrated and then eluted with 4. 5 mol/L nitric acid utilizing stop-flow technique. The enrichment factors were in range of 8. 1￣12. 6 with detection limits of μg/m level ,and the RSD with metals at μg/g level were 2. 3￣5. 0% (n= 7). The method proposed can reduce the matrix interference effectively , and has been applied to the determination of non-rare earth metals atμg/g level in high purity Eu2O3 with satisfactory results.

关键词： flow injection ICP-AES Active carbon-silica gel Sodium diethyldithiocarbamate Stop-flow technique Microcolumn preconcentration High purity Eu_2O_3

Determination of Ciprofloxacin by flow injection Analysis Based on Chemiluminescence System

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Journal of Rare Earths 2006年第3期24卷 285-288页

作者：张卓勇李夏王小丽陈世稆宋保华赵慧春 Department of Chemistry Capital Normal University Beijing 100037 China Department of Chemistry Beijing Normal University Beijing 100875 China

A novel flow injection chemiluminescence （CL） method for the determination of ciprofloxacin （CPLX） was reported. The proposed method is based on luminescence produced by KMnO4-Na2S2O4-Tb^3＋-CPLX chemiluminescence （CL） system. The effects of some critical experimental conditions were discussed and the optimization of working conditions was investigated. The linear dynamic range is 3.00 × 10^-8 - 9.00 × 10^-7 mol ·L-1 and the detection limit for CPLX is 4.40 × 10^-9 mol·L^-1. This method was applied to the determination of CPLX in tablet, urine, and serum samples and the recoveries of real sample analyses were in the range from 110 ± 4 to 104 ± 4.

关键词： ciprofloxacin chemiluminescence terbium flow injection KMnO4 Na2S2O4 rare earths

On-line Preconcentration and Determination of Trace Metals in Water Samples by flow injection Combined with Flame Atomic Absorption Spectrometry via Calix[4]arene Carboxylic Acid Packed Micro-column

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Chemical Research in Chinese Universities 2012年第1期28卷 26-30页

作者： GUO Da-wang, ZHAO Xiao-wei, JIA Qiong and ZHOU Wei-hong College of Chemistry, Jilin University, Changchun 130012, P. R. China College of Chemistry Jilin University Changchun 130012

An adsorbent calix[4]arene carboxylic acid was employed as the adsorption material for on-line flow in jection（FI） micro-column preconcentration coupled with flame atomic absorption spectrometry（FAAS） determination of trace heavy metals（Cu, Pb, Co, Ni and Cd）. Parameters such as the pH, loading time and flow rate of sample, and the concentration, volume and flow rate of eluent were optimized. The enrichment factors are 50.0, 56.5, 11.6, 12.1 and 19.1 for Cu, Pb, Co, Ni, and Cd, respectively, and a sample throughput of 20 h–1 was obtained. The limits of de tection for Cu, Pb, Co, Ni, and Cd were in a range of 1.56―3.91 μg/L, and the relative standard deviations（RSDs） were less than 2.76%（n=7）. Furthermore, the proposed method was successfully applied to the determination of Cu, Pb, Co, Ni, and Cd in certified reference materials and various water samples.

关键词： Calixarene carboxylic acid Preconcentration flow injection Metal ion Flame atomic absorptionspectrometry(FAAS)

Determination of chlorogenic acid by flow injection irreversible biamperometry

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Chinese Chemical Letters 2007年第4期18卷 431-434页

作者： Li Jun Li Qi Feng Chen Lai Bo Yu Zhao Heng Zhong Jun Feng Hao Cheng Hong Xing Kong Jian Ling Wu Department of Biological and Chemical Engineering Guangxi University of Technology Liuzhou 545006 China College of Chemistry and Chemical Engineering Guangxi University Nanning 530004 China

A flow injection irreversible biamperometric method for the determination of chlorogenic acid is described. The proposed method is based on the electrochemical oxidation of chlorogenic acid at pretreated platinum electrode and the reduction of permanganate at another electrode to form an irreversible biamperometric detection system. Under the external potential difference （z^v） of 0 V, in the 0.05 mol/L sulfuric acid, chlorogenic acid can be determined over the range 0.8-120 mg/L with a sample measurement frequency of 80 samples/h. The detection limit is 0.18 mg/L. The proposed method exhibits the satisfactory reproducibility with a relative standard derivation （R.S.D.） of 2.21% for 19 successive determinations of 40 mg/L.

关键词： flow injection Irreversible biamperometry Chlorogenic acid Honeysuckle

Study on Quenching Effect of Holmium (Ⅲ) Ion in Chemiluminescence System of Luminol H_2O_2-Cr(Ⅲ) by flow injection Technique

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Rare Metals 2000年第1期19卷 39-41页

作者：朱智甲河北师范大学河北石家庄 050016

A new chemiluminescence (CL) analytical method for determination of rare earth Ho(Ⅲ) ion is reported. It is based on the quenching effect of Ho(Ⅲ) ion on CL intensity of Luminol H 2O 2 Cr(Ⅲ) system. The detection limit is 3×10 -8 mol/L, the linear range is from 1×10 -7 to 1×10 -4 mol/L; the relative standard deviation is less than 3% (for 2×10 -7 mol/L Ho, n=11). The method was applied to determination of Ho(Ⅲ) in pure samples with satisfactory results.

关键词： Holmium flow injection Chemiluminescence analysis Luminol

Determination of Gossypol in Trace Level by flow injection Analysis with Chemiluminescence Detection

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Chinese Chemical Letters 2006年第1期17卷 57-60页

作者： Bing Chun XUE Er Bao LIU College of Chemistry and Life Sciences Tianjin Normal University Tianjin 300074

This work reports the single-molecule detection of gossypol by flow injection analysis with chemiluminescence method. The method is based on the reaction of luminol with ferricyanid in sodium hydroxide medium sensitized by gossypol. Under the optimum conditions, the CL intensity is proportional to the concentration of gossypol over the range of 1.11×10^-17-2.78×10^-16 mol/L in acid solution and 8.00×10^-11-7.39×10^-8mol/L in neutral solution with correlation coefficients 0.9983 and 0.9905, respectively. The detection limits is 1.60×10^-18 mol/L （S/N=3）. The proposed method has been applied for the determination of the gossypol in cottonseeds and pharmaceutical formulations with satisfactory results.

关键词： Single-molecule detection chemiluminescence flow injection gossypol.

A Novel flow injection Optical Fiber Biosensor for Hypoxanthine Based on Luminol Electrochemiluminescence

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Chemical Research in Chinese Universities 2003年第2期19卷 240-244页

作者： LI Ying xiu ZHU Lian de ZHU Guo yi State Key Laboratory of Electroanalytical Chemistry Changchun Institute of Applied ChemistryChinese Academy of SciencesChangchun 130022P.R.China

IntroductionIn the food industry,the determination of hy-poxanthine in fish meat can be regarded as a simple method for evaluating fish freshness.……

关键词： Electrochemiluminescence flow injection Optical fiber biosensor Sol-gel Ceramic-carbon composite electrode Hypoxanthine Fish freshness