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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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Yaoxue Xuebao

  • Publisher: Wanfang Data
  • FAD Code: YXXB
  • CODEN: YHHPAL
  • ISSN: 0513-4870
  • Abbreviation: Yaoxue Xuebao
  • DOI Prefix: 10.3321/j.issn:0513-4870
  • Other Name(s): Acta Pharmaceutica Sinica
  • Language: Chinese
  • Comments: Fulltext from 1953 V1

Citations 18

"Flow Injection Chemiluminescent Detection Of Acemetacin In KMnO4 - Na2SO3 System"
Yaoxue Xuebao 2004 Volume 39, Issue 11 Pages 925-928
Zhi-Jie Zhang, Ya-Feng Zhuang, Huang-Xian Ju

Abstract: Aim: To study the sensitizing effect of acemetacin (ACE) on the weak chemiluminescent (CL) reaction of KMnO4 with sulfite and establish a fast and convenient method for CL detection of ACE. Methods: Using the sensitizing effect of ACE on KMnO4-Na2SO3 system and flow injection technique to determine the concentration of ACE. Results: Under optimal conditions, the CL intensity of 1.0 x 10-2 mol L-1 H3PO4 - 5.0 x 10^-5 mol L-1 KMnO4 - 4.0 x 10^-4 mol L-1 Na2SO3 was proportional to the concentration of ACE ranging from 1.0 x 10-7 to 1.0 x 10^-5 mol L-1. The detection limit of ACE was 6.9 x 10^-8 mol L-1 at 3s. Satisfactory results were obtained for determination of ACE at 2.5 x 10^-6 mol L-1. Conclusion: The present method showed good precision, high sensitivity and selectivity and could be used for fast and convenient detection of ACE. It would be of significance to the clinical and pharmacological study of acemetacin.

"Monitoring Sub-nanogram Amount Of Acetylspiramycin In Human Urine Using Flow Injection Analysis With Chemiluminescence Detection"
Yaoxue Xuebao 2004 Volume 39, Issue 1 Pages 64-67
XJ Luan, ZH Song, Z Xiao

Abstract: Aim: To establish a new and simple flow injection method for the rapid determination of acetylspiramycin (ASPM). Methods: ASPM was determined by chemiluminescence (CL) method combined with flow injection (FI) technology, which was based on the inhibitive effect of ASPM on the chemiluminescence reaction of the luminol-K3Fe (CN)6 system. Results: The decrease of chemiluminescence intensity was proportional to the logarithm of ASPM concentration (0.1 - 100) ?g?L-1, the detection limit was 40 ng?L-1 (3?). The whole process, including sampling and washing, could be completed in 0.5 min with a RSD less than 3.0% (n = 5). Conclusion: The FI-CL method is of both high sensitivity and good selectivity giving a throughput of 120 h-1. The proposed method was applied successfully to the determination of ASPM in pharmaceutical preparations and human urine without any pre-treatment. It was found that the ASPM concentration reached its maximum after being orally administrated for two hours.

"Determination Of Tea Polyphenols In Green Tea Using Flow Injection-chemiluminescence Inhibition"
Yaoxue Xuebao 2002 Volume 37, Issue 12 Pages 996-998
XL Liao, HY Lang, HT Wang, YR Li

Abstract: AIM To establish a flow injection chemiluminescence (CL) inhibition method for determination of tea polyphenols in green tea. METHODS The flow line of the sample, H2O2 and KIO4 was inserted into luminol carrier solution. The mixed solution was led into the chemiluminescence cell for chemiluminescence reaction to occur and the CL intensity was recorded. RESULTS Tea polyphenols was shown to inhibit the CL reaction of luminol-H2O2-KIO4 system in alkaline solution and the CL emission was inversely correlated with the tea polyphenols concentration. The linear range was 0.4 ? 24.0 ?g?mL-1 with a detection limit of 0.03 ?g?mL-1 and a relative standard deviation of 1.3% (at tea polyphenols concentration 4.0 ?g?mL-1, n = 11). The sampling frequency was 240?h-1. CONCLUSION The method is simple, rapid and can be used for determination of tea polyphenols in green tea.

"Determination Of Rufloxacin Hydrochloride By Terbium Sensitized Chemiluminescence"
Yaoxue Xuebao 2002 Volume 37, Issue 11 Pages 876-879
Y Lu, HC Zhao, CY Sun, L Yi

Abstract: AIM: To study the chemiluminescence mechanism of Tb(III)-RFX-Ce(IV)-Na2SO3 system and establish a new method for the determination of rufloxacin (RFX) in capsules and human urine samples. METHODS: RFX was injected into Na2SO3 standard solution,then mixed with Tb3+, Ce4+ in turn, the chemiluminescence signal was detected by weak luminescence analyzer. RESULTS: The chemiluminescence intensity was linearly related to the concentration of RFX in the range of 2.0 x 10^-9 ? 1.0 x 10^-6 mol L-1 with a detection limit of 3.8 x 10^-10 mol L-1. The familiar excipients such as starch and dextrine do not cause interference. So, this method can be applied to the determination of RFX in tablet. The content and recovery of RFX in urine can be directly detected without pretreatment. CONCLUSION: It provides a simple, rapid, highly sensitive and highly selective method of rufloxacin for pharmacokinetic studies and clinical treatments.

"Chemiluminescence Flow-through Sensor For The Determination Of Vitamin B2 Using Controlled-reagent-release Technology"
Yaoxue Xuebao 2002 Volume 37, Issue 10 Pages 793-797
Wang, L., Song, Z.H.

Abstract: AIM To establish a simple and novel method for the determination of vitamin B2 rapidly in pharmaceutical preparations. METHODS Vitamin B2 was determined by a chemiluminescence (CL) sensor combined with flow-injection (FI) technology. The analytical reagents involved in the CL reaction, luminol and hexacyanoferrate (III), were both immobilized on an anion-exchange resin column in FI system. The CL signal produced by the reaction between luminol and hexacyanoferrate (III), which were eluted from the column through sodium phosphate injection, decreased in the presence of vitamin B2. RESULTS The decreased CL intensity was linearly correlated with the vitamin B2 concentration in the range of 0.01 ? 1.0 ?g?mL-11, the detection limit was 4.0 ng?mL-1 vitamin B2(3?). At a flow rate of 2.0 mL?min-1, the procedure including sampling and washing could be performed in 2 min with a relative standard deviation of less than 3.0%. CONCLUSION The flow sensor exhibited both good sensitivity and stability. It could be reused more than 450 times and has been applied successfully to the analysis of vitamin B2 in pharmaceutical preparations.

"Flow Injection Biamperometric Analysis Of Isoniazid"
Yaoxue Xuebao 2001 Volume 36, Issue 9 Pages 679-682
JC Zhang, C Zhao, JF Song

Abstract: AIM: To establish a simple, rapid, and accurate electrochemical method for on-line determination of isoniazid. METHODS: Based on the flow injection biamperometry for irreversible couple system, and using two preanodized platinum electrodes with the applied potential difference of 0 V, the biamperometric method for the determination of isoniazid has been proposed by coupling the catalytic oxidation of isoniazid and the reduction of platinum oxide. RESULTS: Common excipients, inorganic ions, amino acids, vitamins and proteins do not interfere with the determination. Linear relationship between current and the concentration of isoniazid is obtained in the range of 1.0 x 10^-6 - 1.0 x 10^-4 mol L-1 (? = 0.998, n = 11). The RSD of 1.8% was obtained for 8 successive determinations of 1.0 x 10^-5 mol L-1 isoniazid. CONCLUSION: The proposed method has been shown to be sensitive, selective, rapid (120 samples?h-1), and suitable for the on-line direct determination of isoniazid.

"Terbium Sensitized Chemiluminescence Of Enoxacin"
Yaoxue Xuebao 2001 Volume 36, Issue 8 Pages 613-615
Wang X, Zhao HC

Abstract: AIM: To determine the enoxacin by means of terbium sensitized chemiluminescence in pharmaceutical preparations as well as urine samples. METHODS: Through six-way injection valve Ce4+, H2SO3, Tb3+ and enoxacin (ENX) standard solutions were injected into the flow system in a certain order, the chemiluminescence signal was detected by weak luminescence analyzer. RESULTS: The chemiluminescence intensity was linearly related to the concentration of ENX in the range of 2.0 x 10^-9 - 6.0 x 10^-8 mol L-1 with a detection limit of 4.0 x 10^-10 mol L-1. Relative standard deviation was less than 1.6% (n = 11). CONCLUSION: It provides a sensitive rapid, simple and accuracy measurement of enoxacin for the pharmacokinetic studies.

"Online Monitoring Of Nitrofurantoin In Urine Of Rabbit By A Flow Injection System With A Fiber-optic Chemical Sensor"
Yaoxue Xuebao 1995 Volume 30, Issue 8 Pages 599-604
Li, W.;Chen, J.

Abstract: A flow injection system for monitoring of nitrofurantoin (NFT) in rabbit urine that makes use of a kind of fiber-optic chemical sensor is presented. The NFT-sensitive optrode was combined with a membrane onto which was immobilized pyrenebutyric acid (PBA) as a fluoriprobe. The NFT concentration was determined via dynamic quenching of the fluorescence of PBA. The average recovery was 96.5%-102.9%. The relative standard deviations for within-day and between-day were 3.1%-3.7% and 1.6%-3.8% respectively. The calibration curve was linear in the range from 2 µg mL-1 to 100 µg mL-1 with r = 0.9983. The detection limit of this method was 0.74 µg mL-1. The urine drug concentration-time course in rabbit after oral administration conformed to a one compartment open model with a first order absorption phase. Mean T1/2 value was 0.75±0.14 h. The selectivity was affirmed by HPTLC.
Nitrofurantoin Urine Fluorescence Optrode Sensor Sensor Indirect Method comparison Optical fiber Quenching

"Application Of Flow Injection Analysis To The Studies Of In Vitro Enzymic Degradation And Release Of Nanoparticle Or Nanocapsule"
Yaoxue Xuebao 1994 Volume 29, Issue 12 Pages 925-928
Deng, Y. H.; Li, H. Q.; Luo, X. (SFS)

Abstract: Flow injection analysis (FIA) was applied to study the in vitro release of 5-fluoro-2'-deoxyuridine (FUdR) from solution (I), FUdR-nanoparticle (II) , FUdR-ester-prodrug-nanocapsule (III) and the enzymatic degradation of III with liver, spleen or lung extract. The results showed that the release rate of FUdR from II was slowed down, while the amount of drug released from III was small. It was also confirmed that III could be degraded in the solution containing liver, spleen or lung extract, the major location for the degradation of III was in the liver. A new application of FIA to the pharmaceutical field was developed.
Enzymes Biological Pharmaceutical In vitro monitoring

"Flow Injection Analysis For The Content Test Of Codeine Phosphate Tablets"
Yaoxue Xuebao 1994 Volume 29, Issue 12 Pages 905-909
Fang, Q.; Luo, X. (SFS)

Abstract: A new flow injection system using UV detector and adopting an on-line adsorption column to eliminate the interference of excipients is proposed for the content uniformity test of codeine phosphate tablets. The results obtained with this system agree well with those by the conventional method. The proposed system with a sample volume of 60 µL, sampling frequency of 60/h and precision of 0.8% (RSD, n = 40) is suitable for the content uniformity test and assay of codeine tablets as well as those of other dosage forms.
Codeine phosphate Pharmaceutical Spectrophotometry Interferences Method comparison Column

"Study On The Method For Determination Of Analgin Using Flow Injection Spectrophotometry"
Yaoxue Xuebao 1993 Volume 28, Issue 4 Pages 317-320
Liu WZ, Wang CD, Chen H.

Abstract: A new flow injection spectrophotometric method for the determination of analgin has been developed. The main factors which affect the determination were investigated. The absorption maximum is 650 nm. Under optimum conditions the calibration graph is linear in the range of 0.2-3 mg/ml, the average recovery is 99.8% with a relative standard deviation of 0.5%. The proposed system permits the analysis of about 240 samples per hour and has the advantages of analytical efficiency, sensitivity and accuracy for the determination of analgin.
Analgin Spectrophotometry Optimization Sensitivity

"Construction And Application Of All-solid-state Aconitine Electrochemical Detector In Flow Injection Analysis"
Yaoxue Xuebao 1992 Volume 27, Issue 4 Pages 294-298
Liu WZ, Zuo AL

Abstract: The cited detector exhibits Nernstian response for aconite (I) and its derivatives, with a slope of 56 mV per decade from 30 µM to 30 mM at pH 2 to 7. Direct potentiometry for I in Aconitum kusnezoffi and A. carmichaeli showed recoveries of 96.8 to 98.5%, with coefficient of variation of 1.8 to 3.5%. The detector can be applied to determine I and its derivatives in samples by flow injection analysis. An all-solid-state electrochemical detector used in flow injection analysis for determining aconitine (I), mesaconitine (II) and hypaconitine (III) was constructed (diagram given). For determination of the aconitines in Aconitum kusnezoffii Reichb, Aconitum carmichaeli Debx. and xiaohuoluo pills, sample (10 g) was extracted with 50 mL of 7 M NH3 and 100 mL of ethyl ether, the ether layer was evaporated to dryness and the residue was dissolved in 5 mL each of 0.1 M HCl and 1 M phosphate buffer solution (pH 6.5) and water to 50 mL. A 400 µL portion of the solution was injected into the flow system. Nernstian response was observed for 10 mM to 30 µM I, II or III and the electrode was stable for 6 h. The mean recoveries of I to III were 98.5, 98.3 and 96.8%, respectively; corresponding coefficient of variation were 1.8, 2.4 and 3.5%. Results agreed with those obtained by spectrophotometry (Ch. P. 1990). A new kind of all-solid-state electrochemical detector for very toxic alkaloids such as aconitine, mesaconitine and hypaconitine was studied. It exhibits Nernstian response for these alkaloids with a slope of 56 mV/decade over the concentration range of 3 x 10^-5 to 1 x 10^-2 mol/L at pH 2-7 under the flow condition. Direct potentiometry for the determination of aconitine in Aconitum kusnezoffii Reichb., Aconitum carmichaeli Debx. and Xiaohuoluowan showed average recoveries of 98.5, 98.3 and 96.8% and relative standard deviations of 1.8, 2.4 and 3.5%, respectively. It can be used for the determination of very toxic alkaloids in the above mentioned samples by flow injection analysis It also can be used for the study of the hydrolytic kinetics of aconitine.
Aconitine Mesaconitine Hypaconitine Chinese Pharmaceutical Potentiometry Kinetic Method comparison

"Fluorometric Determination Of Pyridine And Its Derivatives By Flow Injection Analysis"
Yaoxue Xuebao 1991 Volume 26, Issue 12 Pages 928-932
Huang YS, Kubo H, Kinoshita T.

Abstract: A method for the fluorometric determination of pyridine and its derivatives has been developed by flow injection analysis using hydrogen peroxide at high temperature. The reaction system consists of two pumps to deliver reagent and carrier stream, sample injector, reaction coil (0.5 mm ID x 15 m, 150°C), cooling coil (0.5 mm ID x 3 m, 30°C), and cooling coil (0.5 mm ID x 20 cm, 0°C). The wavelengths of the fluorometric spectrophotometer were set at Ex 305-350 nm and Em 380-410 nm, the flow rate of each solution was 1.0 ml/min. The carrier stream was deionized water. The reaction solution containing 10 mmol/L hydrogen peroxide in 0.2 mol/L phosphate buffer (pH 6.0) gave the maximum fluorescence intensity for pyridine and its derivatives. Linear calibration curves were obtained from 5 ng up to 100 ng of pyridine and its derivatives. The coefficient of variations for 2.5 ng (n = 10) and 25 ng (n = 10) of isonicotinic acid, isoniazide and acetylisoniazide were 1.8% and 1.1%, 1.6% and 1.2%, 2.1% and 1.4%, respectively. The detection limit (S/N = 3) was 250 pg for isonicotinic acid, 500 pg for isoniazide, acetylisoniazide, nicotinamide, isonicotinamide, nicotinic acid, and 2.5 ng for pyridine, nicotine, 2-- picoline, 2--picolinamide and picolinic acid. The carrier stream containing organic solvent (methanol, ethanol or acetonitrile) decreased the fluorescence intensity, but in the case of acetonitrile there was less decrease than methanol or ethanol. This method allowed the analysis of 30 samples/h. A method for the flow injection fluorimetric determination of pyridine (I) and its derivatives has been developed using H2O2 at high temperature Sample solution was injected into a carrier stream (1 mL min-1) of water which merged with a stream of 10 mM H2O2 in 0.2 M phosphate buffer of pH 6 (1 mL min-1). The mixture was passed through a rection coil (15 m x 0.5 mm) operated at 150°C, a cooling coil (3 m x 0.5 mm) operated at 30°C and a second cooling coil (0.2 m x 0.5 mm) operated at 0°C before fluorimetric detection at 380 to 410 nm (excitation at 305 to 350 nm). Rectilinear calibration graphs were obtained from 5 to 100 ng of I and its derivatives. Detection limits were 250 pg for isonicotinic acid, 500 pg for isoniazide, acetylisoniazide, nicotinamide, isonicotinamide and nicotinic acid and 2.5 ng for I, nicotine, 2-picoline, 2-picolinamide and picolinic acid.
Pyridine Fluorescence Buffer Heated reaction

"Solvent Extraction-flow Injection Analysis For Determination Of Trimethoprim In Compound Preparations"
Yaoxue Xuebao 1991 Volume 26, Issue 9 Pages 710-713
Liu WZ, Gao JQ

Abstract: Trimethoprim (TMP) in four pharmaceutical preparations (compound sulfamethoxazol tablets, compound tetracycline tablets, compound trimethoprim and sulfamethoxazol tablets; and compound berberine injection) is determined by solvent extraction-flow injection spectrophotometry. It can be extracted into chloroform directly, and the absorbance at a wavelength of 280 nm of the organic phase is measured after phase separation. The manifold comprises two streams. The sample is injected into a 0.2 mol/L NaOH carrier stream, and extracted with chloroform in a 200-cm coil (ID 0.7 mm) after a 50 cm reaction tube (ID 1.0 mm). Calibration graph is linear in the range of 25-150 µg/ml. The average recovery is 101.4% with a relative standard deviation of 1.1%. The proposed system permits the analysis of about 50 samples per hour. Precise results in agreement with those obtained with official methods are achieved. Trimethoprim (I) in four pharmaceutical preparations, viz., (i) compound sulfamethoxazol (II) tablets, (ii) compound tetracycline tablets, (iii) compound I and II tablets, and (iv) compound berberine injection, was determined by the cited method. The solvent extraction - flow injection spectrophotometric system and its principle were described and illustrated. The sample was injected into a carrier stream of 0.2 M NaOH and extracted with CHCl3 on a coil (200 cm x 0.7 mm), and then passed through a reaction tube (50 cm x 1 mm). The absorbance of I in CHCl3 phase was measured at 280 nm. Calibration graph was rectilinear for 25 to 150 µg mL-1 of I. The mean recovery was 101.4%, with coefficient of variation (n = 4) of 1.1%. Results agreed with those obtained by the official methods.
Trimethoprim Pharmaceutical Spectrophotometry Sample preparation Phase separator Solvent extraction

"Determination Of Tetracyclines By Flow Injection Analysis"
Yaoxue Xuebao 1991 Volume 26, Issue 5 Pages 391-394
Liu WZ, Jiang H, Du AZ

Abstract: An accurate, convenient and fast method was proposed for the determination of tetracyclines (tetracycline, chlortetracycline, oxytetracycline, doxycycline and methacycline) and their preparations by flow injection detector based on tetracycline flow-through sensor. The parameters affecting the measurement were discussed. The detector can respond to tetracycline, chlortetracycline, oxytetracycline, doxycycline and methacycline, at the same time. Their slopes are 51-55 mV/decade over the concentration range of 10^-2-5 x 10^-5 mol/L at pH 1.5-3.5. The results obtained are in good agreement with those by biological assay (less than 3% deviation). One hundred samples can be determined in an hour. Tetracycline (I), chlortetracycline (II), oxytetracycline (III), doxycycline (IV) and methacycline (V) in pure form or in their preparations were determined by flow injection analysis with potentiometric detection. The flow injection analysis system and flow-though tetracycline sensor are described (diagram given). At pH 1.5 to 3.5, the relationship between response potential and concentration. was rectilinear up to 10 mM I, -II, -III, -IV and V. One hundred samples could be analyzed in 1 h and results agreed with those by a bioassay.
Tetracycline Potentiometry pH

"Berberine-electrochemical Detector For The Determination Of Berberine-type Alkaloids In Various Chinese Patent Medicines By Flow Injection Analysis"
Yaoxue Xuebao 1991 Volume 26, Issue 4 Pages 315-319
Liu WZ, Peng WB, Yang CH

Abstract: A description is given for the preparation of flow-through sensor and of the incorporation of the sensor into a flow injection analysis system. The parameters affecting the measurement are discussed. An accurate, convenient and rapid method is proposed for the determination of berberine-type alkaloids in various Chinese patent medicines (Coptis chinensis Franch., Phellodendron chinesis Schneid., xianglian wan, zuojin wan, ermiao wan and sanmiao wan). The slope is 54-60 mV/decade over the concentration range of 10^-3-3 x 10^-6 mol/L berberine at pH 2-9.5. Direct potentiometry determination of berberine in various samples showed an average recovery of 99.5-103.5% and a relative standard deviation of 1.3-3.5% at a sampling rate of 120/h. A flow-through sensor and its incorporation into a flow injection analysis system is described and a rapid convenient method for the determination of berberine-type alkaloids in Chinese traditional medicines is proposed. The slope was 54 to 60 mV per decade in the range 1 µM- to 3 mM berberine at pH 2 to 9.5. Recoveries were 99.5 to 103.5%, coefficient of variation were 1.3 to 3.5% and the sampling rate was 120 h-1.
Alkaloids Pharmaceutical Electrochemical analysis Potentiometry pH

"Construction And Application Of Atropine Flow-through Sensor In Flow Injection Analysis"
Yaoxue Xuebao 1990 Volume 25, Issue 6 Pages 451-456
Liu WZ, Wu PZ, Yan Z, Yang CH, Li AJ, Xu RZ

Abstract: A new kind of flow-through sensor for atropine has been studied. It exhibits Nernstian response for atropine with a slope of 54±1 mV/decade over the concentration range of 0.02-200 mmol/L at pH 5-8. The sensitivity coefficients of common compounds were determined. Only bromo-geramine, clonidine, strychnine and amantadine showed remarkable interference. Direct potentiometry for determination of atropine showed an average recovery of 99.2% and a relative standard deviation of 1.3%. It has been used in flow injection analysis (FIA) of atropine, anisodamine and scopolamine and belladonna preparations. Rate of analysis of as high as 60-100 samples/h was achieved.
Atropine Anisodamine Scopolamine Belladonna Potentiometry Sensor pH Sensitivity Interferences

"A Rapid FIA-spectrophotometric Method With Online Extraction For The Content Uniformity Test Of Atropine Sulfate Tablets"
Yaoxue Xuebao 1990 Volume 25, Issue 3 Pages 198-203
Qu XY, He CF, Sun LJ, Wang X, Luo X

Abstract: A rapid spectrophotometric method based on FIA for the content uniformity test of atropine sulfate tablets has been developed. By means of the self-designed FIA system with an online extraction device, many difficulties resulting from extraction, such as slow analytical rate, environmental pollution, poor reproducibility, etc, were overcome, and the routine procedure of the official content uniformity test was tremendously simplified. Results obtained with the proposed method agree well with those obtained with the official test. Furthermore, the proposed method attained a sampling rate of 60 samples per hour, a recovery of 100.0%, a relative standard deviation of 0.7%, and a detection limit of 0.24 µg/ml. Uniform design proves effective to optimize complex FIA conditions, and FIA promises a new approach to test the content uniformity of pharmaceutical tablets.
Atropine sulfate Pharmaceutical Spectrophotometry Sample preparation Extraction Method comparison Optimization