University of North Florida
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Stuart Chalk, Ph.D.
Department of Chemistry
University of North Florida
Phone: 1-904-620-1938
Fax: 1-904-620-3535
Email: schalk@unf.edu
Website: @unf

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Jiu Ru Lu

Abbrev:
Lu, J.R.
Other Names:
Jiuru Lu, Jiu-ru Lu
Address:
Department of Chemistry, Shaanxi Normal University, Xian 710062, China
Phone:
+86-29-5308372
Fax:
+86-29-5307025

Citations 30

"Study On Chemiluminescence System Of Potassium Permanganate/levodopa In Assay Of Levodopa"
Yaowu Fenxi Zazhi 1998 Volume 18, Issue 1 Pages 41-45
Yang Minli, Li Liqing, Feng Manliang and Lu Jiuru

Abstract: A sample solution was diluted with water to 25 mL and then analyzed by FIA (diagram given). The sample mixed with streams of 0.05 M KMnO4 and 1 M H6P4O13 in the flow injection system and the chemiluminescence thus generated was measured. The calibration graph for levodopa (dopa) was linear from 0.4-80 mg/l and the detection limit was 62 g/l. The method was also used to analyze tablets; RSD were 1.6%. The results were compared with those obtained by UV spectrophotometry. None of the investigated co-existing components interfered. The FIA sample throughput was 120/h. In this paper,a new chemiluminescence system of potassium permanganate-levodopa was investigated and a new chemiluminescence method for the determination of levodopa with flow injection technique was established. The concentration range of linear response is 4 x 10^-4~8 x 10^-2g/L.The detection limit is 6.2 x 10^-5g/L with a relative standard deviation of 1.6% for the determination of 4 x 10^-3g/L of levodopa(n=11). The method has been used to determine the content of levodopa in tablets with satisfactory results.
Levodopa Pharmaceutical Chemiluminescence Interferences

"Sensitive Determination Of Phenothiazines In Pharmaceutical Preparation And Biological Fluid By Flow Injection Chemiluminescence Method Using Luminol-KMnO4 System"
Talanta 2007 Volume 71, Issue 3 Pages 1124-1129
Yinhuan Li, Weifen Niu and Jiuru Lu

Abstract: A flow injection chemiluminescence method was described for the determination of four phenothiazine drugs, namely, chlorpromazine hydrochloride, perphenazine hydrochloride, fluphenazine hydrochloride and thioridazine hydrochloride. Strong Chemiluminescence (CL) signal was produced when above-mentioned drug was injected into the mixed stream of luminol with KMnO4. The linear ranges of the method were 0.0020-1.0 ?g/mL chlorpromazine hydrochloride, 0.0040-3.0 ?g/mL perphenazine hydrochloride, 0.0020-5.0 ?g/mL fluphenazine hydrochloride and 0.0050-1.0 ?g/mL thioridazine hydrochloride. The detection limits were 0.4 ng/mL chlorpromazine hydrochloride, 0.7 ng/mL perphenazine hydrochloride, 2 ng/mL fluphenazine hydrochloride and 0.7 ng/mL thioridazine hydrochloride. The proposed method was applied to the determination of chlorpromazine hydrochloride in injections and in mental patient's urine samples and the satisfactory results were achieved. The possible CL reaction mechanism was also discussed briefly. © 2006 Elsevier B.V. All rights reserved.

"Flow Injection Chemiluminescence Determination Of Thiamine Based On Its Enhancing Effect On The Luminol-hydrogen Peroxide System"
Talanta 2002 Volume 57, Issue 4 Pages 661-665
Jianxiu Du, Yinhuan Li and Jiuru Lu

Abstract: A new flow injection chemiluminescence (CL) method is proposed for the determination of thiamine, based upon its enhancing effect on the CL reaction of luminol with hydrogen peroxide in alkaline solution. The method allows the determination of thiamine within 0.05-8 µg mL-1 range with a detection limit (3s) of 0.01 µg mL-1. The relative standard deviation is 1.4% (n=11, 0.5 µg mL-1 thiamine) and the sample throughput is about 90 samples h-1. The method was successfully applied to the determination of thiamine in pharmaceutical preparations.

"Flow Injection Electrogenerated Chemiluminescence Determination Of Vanadium And Its Application To Environmental Water Sample"
Talanta 2002 Volume 57, Issue 1 Pages 53-57
J. J. Li, J. X. Du and J. R. Lu

Abstract: A selective flow injection electrogenerated chemiluminescence(CL) method for the determination of vanadium is described in this paper. It was based on the chemiluminescence reaction of luminol with vanadium(II), which was on-line electrogenerated from vanadate using a flow-through carbon electrolytic cell. Under the optimal conditions, the CL intensity was linear to the concentration of vanadium in the range of 5.0 x 10^-10-1.0 x 10^-7 g mL-1 with a detection limit of 2 x 10^-10 g mL-1 vanadium. The relative standard deviation was 4% for 5.0 x 10^-8 g mL-1 vanadium in 11 repeated measurements. The method has been successfully applied to the determination of vanadium in environmental water samples.

"Flow Injection Chemiluminescence Determination Of Polyhydroxy Phenols Using Luminol-ferricyanide/ferrocyanide System"
Talanta 2001 Volume 55, Issue 6 Pages 1055-1058
Jianxiu Du, Yinhuan Li and Jiuru Lu

Abstract: It was found that the weak chemiluminescence produced from the reaction of polyhydroxy phenols with luminol in alkaline solution could be strongly enhanced by ferricyanide and ferrocyanide. Based on this found, a new flow injection chemiluminescence method is proposed for the determination of four polyhydroxy phenols: pyrogallol, phlorglucinol, quinol and resorcinol. The detection limits of the method are 0.03 µg mL-1 pyrogallol, 0.03 µg mL-1 phlorglucinol, 0.04 µg mL-1 quinol, and 0.02 µg mL-1 resorcinol. The possible mechanism of CL reactions is also discussed briefly.

"Molecular Imprinting-Chemiluminescence Determination Of Norfloxacin Using A Norfloxacin-Imprinted Polymer As The Recognition Material"
Microchim. Acta 2005 Volume 149, Issue 3-4 Pages 239-244
Yunhua He, Jiuru Lu, Hongge Zhang and Jianxiu Du

Abstract: A selective molecular imprinting-chemiluminescence method was developed for the determination of norfloxacin by using a norfloxacin-imprinted polymer as recognition material and the Ce(IV)-sodium sulfite-norfloxacin chemiluminescence reaction as the detection system. The chemiluminescence intensity responded linearly to the concentration of norfloxacin within 1.0 x 10^-7 - 1.0 x 10^-5 mol L-1 with a detection limit of 3 x 10^-8 L-1. The relative standard deviation for 5.0 x 10^-7 mol L-1 norfloxacin solution was 2.4% (n = 7). This method was applied to the determination of norfloxacin in urine samples, and the results obtained were satisfactory.

"Potassium Permanganate-octylphenyl Polyglycol Ether Chemiluminescence System For FIA Determination Of Hydrogen Peroxide"
Microchim. Acta 1997 Volume 126, Issue 1-2 Pages 73-76
Manliang Feng, Zheng Li, Jiuru Lu and Hailong Jiang

Abstract: A mixture solution of aqueous H2O2/octylphenyl polyglycol ether was injected into a flow (2 ml/min) of mixed H2SO4/KMnO4 solution, which then passed through a flow cell for chemiluminescence detection (wavelength not given). The calibration graph was linear from 0.01-60 µM-H2O2, the detection limit was 6 nM and the RSD (n = 7) for 40 nM- to 4 mM H2O2 solutions were 1.6-2.3%. The sampling rate was 60/h. The tolerance of the method to interferents was investigated. The maximum tolerable amounts of interferents are listed. The method was also applied to rain. Results were comparable to those obtained by a fluorescence method (cf. Cheng, 'Fluorescence Analysis', Science Press, China, 1990, p 427) and RSD were 2.3-2.9%. Details of the optimization of the method (i.e. concentrations, flow rate and choice of reagents) are given.
Hydrogen peroxide Rain Chemiluminescence Detection limit Interferences Method comparison Optimization

"Chemiluminescence Flow-injection Analysis Of -lactam Antibiotics Using The Luminol-permanganate Reaction"
Luminescence 2006 Volume 21, Issue 4 Pages 251-255
Yinhuan Li 1 2, Jiuru Lu

Abstract: A new flow injection chemiluminescence (CL) method has been developed for the determination of six ?-lactam antibiotics, including amoxicillin, cefadroxil, cefoperazone sodium, cefazolin sodium, cefradine and ceftriaxone sodium. When the antibiotic was injected into a stream of KMnO4 with alkaline luminol, a strong CL signal was produced. The method allows the measurements of 0.1-50.0 mg/L amoxicillin, 0.1-80.0 mg/L cefadroxil, 1.0-30.0 mg/L cefoperazone sodium, 1.0-30.0 mg/L cefazolin sodium, 3.0-50.0 mg/L cefradine and 3.0-50.0 mg/L ceftriaxone sodium. The detection limits are 0.05 mg/L for amoxycillin, 0.05 mg/L for cefadroxil, 0.4 mg/L for cefoperazonum sodium, 0.4 mg/L for cefazolin sodium, 0.8 mg/L for cefradine and 0.8 mg/L for ceftriaxone sodium. The relative standard deviations in 11 repeated measurements are 0.6%, 0.8%, 1.5%, 1.2%, 0.4% and 0.3% for 3.0 mg/L amoxicillin, 1.0 mg/L cefadroxil, 10.0 mg/L cefoperazone sodium, 10.0 mg/L cefazolin sodium, 10.0 mg/L cefradine and 10.0 mg/L ceftriaxone sodium, respectively. The method was successfully applied to the determination of amoxicillin in pharmaceutical preparations. A possible CL reaction mechanism is also discussed.

"Post-chemiluminescence Behaviour Of Ni2+, Mg2+, Cd2+ And Zn2+ In The Potassium Ferricyanide-luminol Reaction"
Luminescence 2005 Volume 20, Issue 4-5 Pages 266-270
Na Feng, Jiuru Lu *, Yunhua He, Jianxiu Du

Abstract: A new chemiluminescence (CL) reaction was observed when Ni2+, Mg2+, Cd2+ or Zn2+ was injected into the reaction mixture after the finish of the CL reaction of alkaline luminol and potassium ferricyanide. This reaction is described as a post-chemiluminescence (PCL) reaction. The possible mechanism for the PCL was proposed based on studies of the CL kinetic characteristic and the CL spectra. The experimental conditions of the CL reactions were optimized and the feasibility of using the reaction to analyze these metal ions was evaluated. The PCL reaction method operates in the ranges: 1 x 10^-7-8 x 10^-6 g/L Ni2+; 3 x 10^-6-2 x 10^-4 g/L Mg 2+; 8 x 10^-7-1 x 10^-4 g/L Cd 2+; and 2 x 10^-4-2 x 10^-3 g/L Zn2+, with detection limits of 4 x 10^-8 g/mL, 1 x 10^-6 g/mL, 3 x 10^-7 g/mL, 8 x 10 -5 g/mL, respectively.

"Hydrazine-induced Post-chemiluminescence Phenomenon Of Permanganate-luminol Reaction And Its Applications"
Luminescence 2004 Volume 19, Issue 6 Pages 328-332
Jianxiu Du, Jiuru Lu

Abstract: The post-chemiluminescence phenomenon arising from the permanganate-luminol reaction induced by hydrazine and isoniazid was investigated. When hydrazine or isoniazid was injected into the mixture after the end of the reaction of permanganate with alkaline luminol, a new chemiluminescence (CL) reaction was initiated and strong CL signal was detected. A possible CL mechanism is suggested, based upon the studies of the kinetic characteristics of the CL reaction, the UV-visible spectra, the CL spectra and some other experiments. The present reactions allow the determination of 0.1-10.0 mg/L hydrazine and 0.02-1.0 mg/L isoniazid, with detection limits of 0.03 mg/L and 0.006 mg/L, respectively. The method was applied to the determination of isoniazid in pharmaceutical preparations.

"Chemiluminescence Behaviour Of Alkaline Earth Metal Ions In The Potassium Permanganate-fluorescein Reaction"
Luminescence 2003 Volume 18, Issue 6 Pages 341-345
Jianxiu Du, Wenxia Liu, Jiuru Lu

Abstract: A chemiluminescence (CL) signal was observed when alkaline earth metal ion solution, Mg2+ or Ca2+ or Ba2+, was injected into a reaction mixture of fluorescein and potassium permanganate. A possible CL mechanism is proposed based upon the CL, fluorescence and UV-visible spectra. Furthermore, the feasibility of the application of these reactions to the analysis of these alkaline earth metal ions was evaluated and the analytical parameters of the methods were determined.

"Determination Of Parathion Residues In Rice Samples Using A Flow Injection Chemiluminescence Method"
Luminescence 2003 Volume 18, Issue 5 Pages 245-248
Xiaoyu Liu, Jianxiu Du, Jiuru Lu*

Abstract: A sensitive flow injection chemiluminescence method is described for the determination of parathion pesticide, based upon its direct chemiluminescence reaction with luminol and hydrogen peroxide in the presence of non-ionic surfactant polyethylene glycol 400. Under the selected experimental conditions, the concentration of parathion is proportional to the CL intensity in the range 0.02-1.0 mg/L. The detection limit was 0.008 mg/L and the relative standard deviation was 2.8% for 0.2 mg/L parathion solution (n = 11). This method was successfully applied to the determination of parathion residue in rice samples.

"Flow Injection Chemiluminescence Determination Of Captopril Based On Its Enhancing Effect On The Luminol-ferricyanide/ferrocyanide Reaction"
Luminescence 2002 Volume 17, Issue 3 Pages 165-167
Jianxiu Du, Yinhuan Li, Jiuru Lu

Abstract: A new flow injection chemiluminescence method is described for the determination of captopril. It is based on the enhancing effect of captopril on the chemiluminescence reaction of luminol with potassium ferricyanide in alkaline solution in the presence of potassium ferrocyanide. The method allows the determination of captopril over 0.1-40 µg/mL range, with a relative standard deviation (SD) of 1.0% for the determination of 0.5 µg/mL captopril solution in 11 repeated measurements. The method was satisfactorily applied to the determination of captopril in commercial captopril tablets. The possible reaction mechanism is also discussed briefly.

"Chemiluminescence Reaction Of Potassium Permanganate-formaldehyde-uric Acid System"
Fenxi Huaxue 2005 Volume 33, Issue 4 Pages 535-537
Liu Mei,He Yunhua,Lü Jiuru

Abstract: Chemiluminescence reaction of uric acid with potassium permanganate in the presence of formaldehyde as an enhancer was investigated. A new chemiluminescence method for the determination of uric acid with flow injection technique was developed. The detection limit is 6 x 10^-6 g/L, the relative standard deviation is 1.8% (4.0 x 10^-4 g/L uric acid, n = 11), the linear range is 2.0 x 10^-5-5.0 x 10^-3 g/L. The method has been successfully applied to the determination of uric acid in human urine samples. The mechanism of the reaction was also discussed.

"Chemiluminescence Determination Of Trace Ascorbic Acid With Soluble Manganese (IV)-formaldehyde System"
Fenxi Huaxue 2004 Volume 32, Issue 6 Pages 752-754
Zhu Xinghua, He Yunhua, Liu Mei, Du Jianxiu, Lu Jiuru

Abstract: A novel chemiluminescence method to determine ascorbic acid with flow injection technique, based on formaldehyde enhancing the chemiluminescence from the oxidation of ascorbic acid by soluble Mn(IV), has been developed. Under optimum conditions, the linear dynamic range for the determination of ascorbic acid was from 6.0 x 10^-8 to 2.0 x 10^-5 mol/L, and the detection limit was 2 x 10^-8 mol/L. The relative standard deviation for the determination of 1.0 x 10^-6 mol/L ascorbic acid (n = 11) was 2.3%. The method has been applied to the determination of ascorbic acid in tablets and injections and the results were in good agreement with those obtained by pharmacopoeia method.

"Chemiluminescence Reaction Of Luminol-[potassium Ferricyanide-potassium Ferrocyanide]-ethamsylate System"
Fenxi Huaxue 2002 Volume 30, Issue 6 Pages 742-744
Li Yinhuan, Du Jianxiu, Lu Jiuru

Abstract: It was found that a weak chemiluminescence (CL) was produced from the reaction of ethamsylate with luminol in alkaline solution. The CL intensity was greatly enhanced in the presence of potassium ferricyanide and potassium ferrocyanide. Based on these observations, a new CL system, luminol-[potassium ferricyanide-potassium ferrocyanide]-ethamsylate system, was proposed for the determination of ethamsylate. The CL intensity is linear with the concentration of ethamsylate in the range of 4.0 x 10^-6 - 1.0 x 10^-4 g/L. The relative standard deviation is 1.4% (2.0 x 10^-5 g/L ethamsylate solution, n = 11) with a detection limit of 1 x 10^-6 g/L. The method has been successfully applied to the determination of ethamsylate in ethamsylate injection. The reaction mechanism was also discussed briefly.

"Determination Of Trace Amounts Of Sulfide By Flow-injection Chemiluminescence Method"
Fenxi Huaxue 2001 Volume 29, Issue 2 Pages 189-191
Du Jianxiu, Li Yinhuan, Lu Jiuru

Abstract: A new flow-injection chemiluminescence method for the determination of trace amounts of sulfide was developed. It is based on the catalysis of sulfide to chemiluminescence reaction between luminol and hydrogen peroxide. The linear range extends from 2.0 x 10^-9 to 8.0 x 10^-7 g/mL and the detection limit is 5.6 x 10^-10 g/mL. The relative standard deviation (RSD) is less than 5% for 1.0 x 10^-7 g/mL sulfide solution in eleven repeated measurements. The method has the advantages of simplicity, rapidity, sensitivity and has also been applied to the determination of trace amounts of sulfide in water samples.

"Flow Injection Chemiluminescence Determination Of Adreson With Electrogenerated Manganese (III)"
Fenxi Huaxue 2000 Volume 28, Issue 9 Pages 1126-1128
Chen Xiaoni, Zhang Chengxiao, Lü Jiuru

Abstract: A novel flow injection chemiluminescence method for the determination of adreson has been developed, which was based on the chemiluminescence reaction between adrenson and a highly active Mn(III) electrogenerated by a constant current electrolysis on-line. The linear range for adreson is from 1 x 10^-8 to 2 x 10^-5 g/mL, the detection limit is 5 x 10^-9 g/mL and the relative standard deviation in 2.0%. The simple, rapid and reproducible method has been applied to determine adrenson in the tablets and injections with satisfactory results.

"Chemiluminescence Reaction With Soluble Manganese(IV) As The Oxidant"
Acta Chim. Sin. 2005 Volume 63, Issue 8 Pages 729-733
HE, Yun-Hua LÜ, Jiu-Ru* ZHU, Xing-Hua DU, Jian-Xiu

Abstract: It was found that soluble manganese(IV) could react with more than 30 organic and inorganic compounds to produce strong chemiluminescence signal in the presence of formaldehyde. The reaction conditions were optimized and a new flow injection chemiluminescence method for the determination of four cephalosporin drugs, namely ceftriaxone sodium, cefazolin sodium, cefradine and cefoperazone sodium, was established. The method was applied to the determination of cephalosporins in pharmaceutical preparations. Meanwhile, the chemiluminescence reaction mechanism was also discussed briefly.

"Flow-injection Chemiluminescence Analysis Of Cloperastione Hydrochloride"
Anal. Lett. 2006 Volume 39, Issue 12 Pages 2475-2481
Shuwen Sun; Jiuru Lu

Abstract: A new chemiluminescence (CL) reaction was observed when cloperastine hydrochloride was injected into the reaction mixture after the CL reaction of Ce(IV) and sodium sulfite finished. A new flow injection CL method for the determination of cloperastine hydrochloride was established based on the CL reaction. The relative standard deviation (RSD) for the determination of cloperastine hydrochloride was 1.3% (n = 11, c = 1.0 x 10^-6 g/mL). The CL intensity responded linearly to the concentration of cloperastine hydrochloride in the range 2.0 x 10^-7 ? 2.0 x 10 -5 g/mL (r = 0.9962). The detection limit was 5 x 10 -8 g/mL cloperastine hydrochloride. The method had been applied to the determination of cloperastine hydrochloride in tablets with satisfactory results. Copyright © Taylor & Francis Group, LLC.

"Determination Of Monocrotophos Pesticide By Flow Injection Chemiluminescence Method Using Luminol-Hydrogen Peroxide System"
Anal. Lett. 2003 Volume 36, Issue 5 Pages 1029-1038
Jianxiu Du, Xiaoyu Liu, Jiuru Lu

Abstract: A simple flow injection chemiluminescence method is described for the determination of monocrotophos pesticide, based upon the direct reaction of monocrotophos with luminol and hydrogen peroxide in alkaline medium in the presence of an enhancer of sodium chloride. The CL intensity was linear related to monocrotophos concentration in the range of 2.0 x 10 -;8-1.0 x 10 -;6 g/mL with a detection limit of 7 x 10 -;9 g/mL. The relative standard deviation was less than 3% for 1.0 x 10 -;7 g/mL monocrotophos in eleven repeated measurements. This method was successfully applied to the determination of monocrotophos in water samples. The possible reaction mechanism was also discussed briefly.

"Flow Injection Chemiluminescence Determination Of Thiol-Containing Drugs Based On A Quinine-Sensitized Permanganate Reaction"
Anal. Lett. 2003 Volume 36, Issue 4 Pages 871-879
Yinhuan Li, Ahui Zhang, Jianxiu Du, Jiuru Lu

Abstract: A new flow injection chemiluminescence method is presented for the determination of four thiol-containing drugs, cysteine, N-acetylcysteine, glutathione, and captopril. It was found that the oxidation of these drugs with potassium permanganate accompanied by weak chemiluminescence in acidic condition. The presence of quinine sulfate enhanced chemiluminescence signal greatly. The method allows to determine 0.02-2 µg mL -;1 cysteine, 0.05-2 µg mL -;1 N-acetylcysteine, 0.05-2 µg mL -;1 glutathione, and 0.02-1 µg mL -;1 captopril with limits of detection of 0.01 µg mL -;1, 0.02 µg mL -;1, 0.02 µg mL -;1, and 0.006 µg mL -;1, respectively. The relative standard deviations were less than 2% (n = 11) and the sample measurement frequency was about 120 samples h -;1. The application of this method was demonstrated by the analysis of cysteine and captopril in some pharmaceutical preparations.

"Chemiluminescence Flow Injection Analysis Of Amoxycillin By A Permanganate-based Reaction"
Anal. Lett. 2002 Volume 35, Issue 14 Pages 2295-2304
Jianxiu Du, Yinhuan Li, Jiuru Lu

Abstract: A new application of chemiluminescence for the determination of amoxycillin in flow injection mode is presented. The method is based upon the direct chemiluminescence reaction of amoxycillin with KMnO4 in acidic medium in presence of quinine sulfate. The chemiluminescence intensity was linearly related to the concentration of amoxycillin within 0.05-10 µg mL-1 range with a detection limit (3s) of 0.02 µg mL-1 and a sample measurement frequency of 90 samples h-1. The relative standard deviation is 2.3% for 1.0 µg mL-1 amoxycillin solution in 11 repeated measurements. The method was successfully applied to the analysis of amoxycillin in capsules.

"Flow Injection Chemiluminescence Determination Of Ethamsylate Based On Permanganate Oxidation"
Anal. Lett. 2002 Volume 35, Issue 3 Pages 463-472
Jianxiu Du; Yinhuan Li; Ying Tang; Jiuru Lu

Abstract: A new flow injection chemiluminescence method is described for the determination of ethamsylate. The method is based on the measurement of the chemiluminescence signal produced from oxidation of ethamsylate by potassium permanganate in acidic solution, enhanced by formic acid. The method allows the determination of ethamsylate over the range 1.0 x 10^-8-2.0 x 10^-6 g mL-1 with a sample measurement frequency of 180 samples h-1. The detection limit for ethamsylate is 5 x 10^-9 g mL-1 and the relative standard deviation is 1.4% for 5.0 x 10^-7 g mL-1 ethamsylate solution in eleven replicate measurements. The method was successfully applied to the determination of ethamsylate in pharmaceutical preparations. A brief discussion on the chemiluminescence reaction mechanism has also given.

"Flow-injection Post Chemiluminescence Determination Of Atropine Sulfate"
Anal. Chim. Acta 2006 Volume 580, Issue 1 Pages 9-13
Shuwen Sun and Jiuru Lu

Abstract: A new post chemiluminescence (PCL) reaction was observed when atropine sulfate was injected into the reaction mixture after the finish of CL reaction of Ce(IV) and sodium sulfite. The possible mechanism for the PCL reaction was discussed via the investigation of the CL kinetic characteristics, the CL spectra, the UV absorption spectra and the fluorescence spectra of some related substances. The flow injection PCL method for the determination of atropine sulfate was established. The relative standard deviation (RSD) was 2.8% (n = 11, c = 5.0 x 10^-6 g mL-1). The PCL intensity responded linearly to the concentration of atropine sulfate in the range 1.0 x 10^-6 to 5.0 x 10^-5 g mL-1 with a linear correlation of 0.9947. The detection limit was 4 x 10^-7 g mL-1 atropine sulfate. The method had been applied to the determination of atropine sulfate in the tablets and the results were consistent with the method of Chinese pharmacopoeia. © 2006 Elsevier B.V. All rights reserved.

"Flow Injection Chemiluminescence Determination Of Naproxen Based On KMnO4-Na2SO3 Reaction In Neutral Aqueous Medium"
Anal. Chim. Acta 2006 Volume 577, Issue 1 Pages 107-110
Yinhuan Li and Jiuru Lu

Abstract: A simple, rapid and sensitive flow injection chemiluminescence (CL) method is described for the determination of naproxen. It was found that strong CL signal was generated when naproxen was mixed with KMnO4 and Na2SO3 in neutral aqueous medium. Under the optimum experimental conditions, the CL intensity was linearly related to the concentration of naproxen from 4.0 x 10^-9 to 1.0 x 10^-6 g mL-1 (r = 0.9993). The detection limit was 2 x 10^-9 g mL-1 naproxen, the relative standard deviation for 1.0 x 10^-7 g mL-1 naproxen solution was 1.5% (n = 11) and the sampling frequency was 120 h-1. The method was applied to the determination of naproxen in pharmaceutical preparation with satisfactory results. The mechanism of CL reaction was discussed briefly. © 2006.

"Flow Injection Chemiluminescence Determination Of Epinephrine Using Epinephrine-imprinted Polymer As Recognition Material"
Anal. Chim. Acta 2003 Volume 489, Issue 2 Pages 183-189
Jianxiu Du, Lihua Shen and Jiuru Lu

Abstract: A flow injection chemiluminescence (CL) method using epinephrine-imprinted polymer as recognition material was investigated for the determination of epinephrine. The analyte, epinephrine, was selectively and temporarily adsorbed on the epinephrine-imprinted polymer, which was packed into a flow-cell placed in front of the window of a photomultiplier tube. Afterwards, the CL reagent, the emerging stream of luminol (presence of potassium ferrocyanide) and potassium ferricyanide flowed through the flow-cell and reacted with epinephrine adsorbed on the polymer to produce strong CL. The CL intensity responded linearly to the logarithm of the concentration of epinephrine within 5.0 x 10^-9 to 1.0 x 10^-7 mol/l range with a detection limit of 3 x 10^-9 mol/l. The RSD for 2.0 x 10^-8 mol/l of epinephrine solution was less than 5% (n=7). Interference experiments demonstrated that the application of molecular imprinted polymer (MIP) to CL analysis could be improved the selectivity of the method greatly. Tests of the recovery for known amount of epinephrine in serum were carried out and satisfactory results were obtained. At the same time, the binding characteristic of the polymer to epinephrine was evaluated by the batch method and the dynamic method.

"Sensitive And Selective Determination Of Molybdenum By Flow Injection Chemiluminescence Method Combined With Controlled Potential Electrolysis Technique"
Anal. Chim. Acta 2003 Volume 481, Issue 2 Pages 239-244
Jianxiu Du, Jianjun Li, Lingjuan Yang and Jiuru Lu

Abstract: A sensitive and selective flow injection chemiluminescence (CL) method combined with controlled potential electrolysis technique was described for the determination of molybdenum. The method is based on the chemiluminescence reaction of luminol with unstable molybdenum(III) in alkaline solution. The molybdenum(III) was on-line reduced from molybdenum(VI) via controlled potential electrolysis technique using a homemade flow-through carbon electrolytic cell at the potential of -0.6 V (versus Ag/AgCl). The method allows the determination of molybdenum in the 5.0 x 10^-10 to 5.0 x 10^-7 g mL-1 range with a limit of detection (3s) of 5 x 10^-11 g mL-1 molybdenum. The relative standard deviation is 2.6% for the 1.0 x 10^-9 g mL-1 molybdenum solution in 11 repeated measurements. This method was successfully applied to the determination of molybdenum in water samples.

"Investigation On The Chemiluminescence Reaction Of Luminol-H2O2-S2-/R-SH System"
Anal. Chim. Acta 2001 Volume 448, Issue 1-2 Pages 79-83
Jianxiu Du, Yinhuan Li and Jiuru Lu

Abstract: The enhancing effect of sulfide and three thiol-containing compounds (glutathione, -cysteine, N-acetylcysteine) on the chemiluminescence reaction of luminol with hydrogen peroxide in alkaline solution has been found. The flow injection chemiluminescence method for the determination of these substances has been established. Detection limits were 6 x 10^-10 g/ml sulfide, 9 x 10^-10 g/ml glutathione, 3 x 10^-8 g/ml -cysteine and 7 x 10^-9 g/ml N-acetylcysteine, respectively. The mechanism of chemiluminescence reaction has also been discussed briefly.

"Investigating The Post-chemiluminescence Behavior Of Phenothiazine Medications In The Luminol–potassium Ferricyanide System: Molecular Imprinting–post-chemiluminescence Method For The Determination Of Chlorpromazine Hydrochloride"
Anal. Bioanal. Chem. 2006 Volume 385, Issue 1 Pages 153-160
Weifen Niu, Na Feng, Fei Nie, and Jiuru Lu

Abstract: A new post-chemiluminescence (PCL) phenomenon was observed when phenothiazine medications were injected into the reaction mixture after the chemiluminescence (CL) reaction of luminol and potassium ferricyanide had finished. A possible reaction mechanism was proposed based on studies of the kinetic characteristics of the CL, CL spectra, fluorescence spectra, and on other experiments. The feasibility of determining various phenothiazine medications by utilizing these PCL reactions was examined. A molecular imprinting-post-chemiluminescence (MI-PCL) method was established for the determination of chlorpromazine hydrochloride using a chlorpromazine hydrochloride-imprinted polymer (MIP) as the recognition material. The method displayed high selectivity and high sensitivity. The linear range of the method was 1.0 x 10^-8 - 1.0 x 10^-6, with a linear correlation coefficient of 0.9985. The detection limit was 3 x 10^-9 g/ml chlorpromazine hydrochloride, and the relative standard deviation for a 1.0 x 10^-7 g/ml chlorpromazine hydrochloride solution was 4.0% (n=11). The method has been applied to the determination of chlorpromazine hydrochloride in urine and animal drinking water with satisfactory results