Flow‐Injection Chemiluminometric Analysis of Thyroxine Hormone in a KMnO,4‐Na2SO3 System

An analytical method consisting of flow injection sampling and chemiluminescence detection for the determination of thyroxine hormone is described. It is based on the weak chemiluminescent reaction of KMnO₄ ‐ Na₂SO₃ in acidic medium, which is enhanced by the addition of thyroxine hormone. The chemiluminescence intensity was correlated linearly with concentration of thyroxine in the range of 1.0 × 10^?7 – 2.0 × 10^?6 mol L^?1 (r² = 0.9976) with a relative standard deviation (n = 4) in the range of 1.0 – 1.9%. The limit of detection (3σ blank) is 5.0 × 10^?9 mol L^?1 with a sample throughput of 180 h^?1. The method has been applied to the determination of thyroxine in pharmaceutical preparations and the results are in good agreement with the value reported. Metal and non‐metal ions and some organic compounds commonly present in tablets and some amino acids were also studied for thyroxine determination.     

Chemiluminescence Determination of Sulpiride in Pharmaceutical Preparations and Biological Fluids Based on KMnO4‐Tween 80 Reaction

Chemiluminescence (CL) of an acidic KMnO₄ system in the presence of Tween 80 was investigated for the determination of sulpiride. Strong CL was recorded when a mixture of sulpiride and Tween 80 was injected into acidic KMnO₄ solution. The experimental parameters affecting the CL intensity were carefully studied using flow injection mode. Under the optimum conditions, the CL intensity was proportional to the concentration of sulpiride in the range of 5.0 × 10⁻⁷ ∼ 1.0 × 10⁻⁴ g mL⁻¹. The detection limit is 1.6 × 10⁻⁷ g mL⁻¹ sulpiride, and the relative standard deviation for 1.0 × 10⁻⁶ g mL⁻¹ sulpiride solution is 1.5% (n = 11). The proposed method has been successfully applied to the determination of sulpiride in tablets and in spiked human plasma and urine samples.     

高锰酸钾—连二亚硫酸钠—核黄素化学发光体系的研究

在酸性溶液中，高锰酸钾能氧化核素产生化学发光，连二亚硫酸钠的存在可使发光强度大大增强，采用流动注射技术，建立了测定核黄素的化学发光分析法，方法的检出限为６．２×１０＾－８ｇ／ｋｍＬ，线性范围为２×１０＾－７～１×１０＾－５ｇ／ｍＬ对４．０×１０＾－６ｇ／ｍＬ核黄素进行１１次平行测定，相对标准偏差为１．８％，方法用于针剂和片剂中核黄素测定，与药典标准方法－紫外分光光度法对照，相对误差不大于±２％。     

Construction and Performance Characterization of Ion‐Selective Electrodes for Potentiometric Determination of Paroxetine Hydrochloride in Pharmaceutical Preparations and Biological Fluids

Three types of ion‐selective electrodes: PVC membrane, modified carbon paste (CPE), and coated graphite electrodes (CGE) have been constructed for determining paroxetine hydrochloride (Prx). The electrodes are based on the ion pair of paroxetine with sodium tetraphenylborate (NaTPB) using dibutyl phthalate as plasticizing solvent. Fast, stable and potentiometric response was obtained over the concentration range of 1.1×10^?5–1×10^?2 mol L^?1 with low detection limit of 6.9×10^?6 mol L^?1 and slope of a 56.7±0.3mV decade^?1 for PVC membrane electrode, the concentration range of 2×10^?5–1×10^?2 mol L^?1 with low detection limit of 1.2×10^?5 mol L^?1 and slope of a 57.7±0.6 mV decade^?1 for CPE, and the concentration range of 2×10^?5–1×10^?2 mol L^?1 with low detection limit of 8.9×10^?6 mol L^?1 and slope of a 56.1±0.1 mV decade^?1 for CGE. The proposed electrodes display good selectivity for paroxetine with respect to a number of common inorganic and organic species. The electrodes were successfully applied to the potentiometric determination of paroxetine hydrochloride in its pure state, its pharmaceutical preparation, human urine and plasma.     

Flow Injection Chemiluminescence Determination of Puerarin in Pharmaceutical Preparations Using Eosin Y‐Fenton System

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 1.7% for 4.0×10^?7 mol/L puerarin (n=11). The proposed method was applied to the determination of puerarin in a puerarin injection with satisfactory results.     

H2O2的KMnO4-Luminol化学发光体系测定

在碱性介质中 ,H2O2 能极大地增强KMnO4-Luminol的化学发光强度 ,据此建立一种测定H2O2 的方法 ;该法的线性范围为5.0×10-8 ～5.0×10-5 mol/L,检出限为1.4×10-8 mol/L;利用该法测定了雨水中H2O2 的含量 ,并进行了回收率测定 ,回收率在95%～103% ,结果令人满意     

Automated Sequential‐injection Chemiluminescence Determination of Glucosamine Sulphate via Luminol‐Hydrogen Peroxide System

A highly sensitive automated sequential‐injection chemiluminescence (SIA‐CL) method for determination of glucosamine sulphate (GLS) was developed. The goal of the present work is the evaluation of the enhancement effect of the investigated drug glucosamine sulphate on the chemiluminescence reaction between luminol and H₂O₂ in alkaline medium of 1.0 × 10^?2 mol L^?1 sodium hydroxide at pH 11. The experimental conditions affecting the CL reaction such as the sequence of the reagents, concentrations, flow rate and aspirated volumes of reactants were systematically investigated and optimized. Under optimum conditions 50 μL of 1.0 × 10^?3 mol L^?1 luminol, 30 μL of a GLS test solution and 50 μL of 1.0 × 10^?2 mol L^?1 H₂O₂ were used and the luminescing zone was pushed into the detector at a flow rate 100 μL s^?1. The proposed method recorded high sensitivity, accuracy and simplicity that could be clarified as linear concentration range 1.0‐2000 ng mL^?1 with rectilinear part (r = 0.9992, n = 9) and limit of detection 0.3 ng mL^?1, along with relative standard deviation 1.3%. It was found that the developed method can be used directly to determine the investigated drug GLS in its pharmaceutical dosage forms and in spiked serum and urine by diluting the samples for a 1000 fold. The obtained results were statistically analyzed and compared with those obtained by the reported method.     

头孢曲松钠的流动注射化学发光抑制法测定

基于吖啶橙在氢氧化钠介质中，能被高锰酸钾氧化产生较强的化学发光，头孢曲松钠能强烈抑制其化学发光，建立了高锰酸钾-吖啶橙-头孢曲松钠化学发光抑制测定头孢曲松钠的方法；头孢曲松钠的质量浓度与化学发光强度在2～20mg／L范围内呈良好线性关系，方法的检出限为8μg/L，对10mg／L头孢曲松钠连续进行11次测定的相对标准偏差为3．1％；方法用于头孢曲松钠针剂测定，取得了满意的结果。     

Flow—injection Chemiluminescence Determination of Reserpine in Medicine and Biological Fluids with Controlled—Reagent—Release Technology

A sensitive and rapid chemiluminescence(CL) flow injection with controlled-reagent-release technology for the determination of reserpine was proposed.The Cl reagents,luminol and dichromate,uses in this sensor,were all immobilized on anion-exchange resin.Through injection of 100μl of water,the reagents on the anion-ex-change resin column were eluted and in the presence of reserpine ,the CL intensity was decreased,by which reserpine could be sensed.Reserpine was quantified by measuring the decrement of CL intensity,which was observed linear with the logrithm of reserpine concentration in the rage of 1.0-500.0ng/mL,and the limit of detection was 0.4ng/mL(3σ)with a relative standard deviation of less than 3.0?The proposed procedure was applied in the assay of reserpine in pharmaceutical preparation and biological fhuids without any pre-treatment process and with sampling frequencies of 72 times per hour.     

Voltammetric Sensor for Sodium Nitroprusside Determination in Biological Fluids Using Films of Poly‐L‐Lysine

Sodium nitroprusside (NP), a commercial vasodilator, can be pre‐concentrated on vitreous carbon electrode modified by films of 97.5%: 2.5% poly‐L ‐lysine (PLL): glutaraldehyde (GA). This coating gives acceptable anion exchange properties whilst giving the required improvement of adhesion to the glassy carbon electrode surface. Linear response range and detection limit on nitroprusside in B‐R buffer pH 4.0, were 1×10^?6 to 2×10^?5 mol L^?1 and 1×10^?7 mol L^?1, respectively. The repeatability of the proposed sensor, evaluated in term of relative standard deviation, was measured as 4.1% for 10 experiments. The voltammetric sensor was directly applied to determination of nitroprusside in human plasma and urine samples and the average recovery for these samples was around 95–97% without any pre treatment.     

ClO3--SO32--Rh6G-SDBS体系的化学发光及其用于亚硫酸根测定

Based on the micelle synergism mechanism, a chemiluminescence （CL） flow system for the determination of sulfite was described. The CL signal generated from the reaction of chlorate with sulfite in acidic solution was very weak, while the interfusion of sodium dodecylbenzenesulfonate （SDBS） resulted in a highly chemiluminescent intensity. The major goal of this work was to investigate and develop the SDBS rnicelle synergetic CL system. The mechanism was proposed and proved by spectrometry. The results indicated that the unique structure of SDBS micelles prorooted the aggregation of rhodamine 6G （Rh6G） and a much easier energy transfer, leading to a marked shift to red in the CL emission. This CL system was developed for the determination of sulfite and the concentration of sulfite was proportional to the CL intensity in the range of 5.0× 10^-8--1.0× 10^-5 mol/L with the detection limit of 1.7×10^-8 mol/L （S/N=3）. The relative standard deviation was 3.3% for 1.0×10^ 6 mol/L sulfite solution with eleven repeated measurements. This method was successfully applied to the determination of sulfite in powder sugar.     

Sensitive Determination of Nanogram Levels of Diacerein in a Pharmaceutical Formulation by Flow Injection Chemiluminescence Analysis

A simple, sensitive and inexpensive flow injection chemiluminescence (FI‐CL) method for the determination of diacerein was proposed. It was based on the greatly enhancive effect of diacerein on the CL reaction between luminol and hydrogen peroxide in alkaline medium. The enhanced CL intensity was linear with the concentration of diacerein over the range 1.0–500 ng/mL with a detection limit (3σ) of 0.2 ng/mL. The relative standard deviation was 1.1% (n = 8, 20 ng/mL diacerein) and the sample throughput was about 120 samples h^?1. This simple method has been successfully applied for the determination of diacerein in a pharmaceutical formulation without interference from its potential impurities. The degradation of diacerein was also investigated briefly.     

Europium(III)-Sensitized Chemiluminescence Determination of Ibuprofen in Pharmaceutical Preparations and Biological Fluids

Abstract

Chemiluminescence reaction of the system containing europium(III) ion, KMnO₄, Na₂SO₃, and ibuprofen was investigated for the determination of ibuprofen. The introduction of Eu(III) ion into the system of KMnO₄-Na₂SO₃-ibuprofen caused a significant increase in the chemiluminescence signal. The increment of the chemiluminescence signal is proportional to ibuprofen concentration in the range of 5.0 × 10^?8–5.0 × 10^?6 g/ml with a detection limit of 1 × 10^?8 g/ml. The relative standard deviation for 1.0 × 10^?7 g/ml ibuprofen solution was 1.7% (n = 11). The proposed method was successfully applied to determine ibuprofen in tablets and human plasma.     

NaIO4-H2O2-盐酸异丙肾上腺素-Cu2+体系化学发光测定盐酸异丙肾上腺素

在磷酸介质中,过氧化氢存在下,加入少量Cu2+的盐酸异丙肾上腺素试液经80℃水浴加热处理后与高碘酸钠反应产生强烈的化学发光.据此,结合流动注射技术建立了一种测定盐酸异丙肾上腺素的化学发光分析新方法.方法的线性范围为1.0×10-9～7.0×10-7 g/mL,检出限为4.0×10-10g/mL,相对标准偏差为3.0%(1.0×10-8g/mL盐酸异丙肾上腺素,n=11).该法用于注射液中盐酸异丙肾上腺素的测定,回收率为97%～103%.     

盐酸倍他司汀对鲁米诺-高碘酸钾体系后发光作用机理的探讨及其快速测定

实验发现盐酸倍他司汀对鲁米诺-高碘酸钾发光体系具有后化学发光作用,并对其作用机理进行了探讨。结合流动注射技术,优化了反应条件,并建立了测定盐酸倍他司汀的新方法。该方法简便、快速、准确,线性范围为2.0×10^-7－4.0×10^-4mol／L（r=0.9975）,检出限为1.0×10^-7mol／L;对4.0×10^-5mol／L的盐酸倍他司汀进行了11次平行测定,相对标准偏差为2.9％。方法成功地用于盐酸倍他司汀片中盐酸倍他司汀的测定。     

New Validated Potentiometric Determination of Vasodilator Pentoxifylline in its Pharmaceutical Formulations and Biological Fluids

The construction and performance characteristics of pentoxifylline selective electrodes were developed. Two types of electrodes: plastic membrane I and coated wire II were constructed based on the incorporation of pentoxifylline with phosphotungstic acid (PTA). The influence of membrane composition, kind of plasticizer, pH of the test solution, soaking time, and foreign ions on the electrodes was investigated. The electrodes showed a Nernstain response with a mean calibration graph slope of 56.77 ± 0.19 and 55.76 ± 0.71 mV decade^‐1 at 25 °C for electrode I and II respectively, over pentoxifylline concentration range from 1.0 × 10^‐5‐1.0 × 10^‐2 and 9.0 × 10^‐6‐1.0 × 10^‐2 mol L^‐1, with detection limits 4.89 × 10^‐6 and 3.90 × 10^‐6 mol L^‐1 for electrode I and II, respectively. The pH range of the constructed electrodes was 4‐6. Interferences from common cations, alkaloids, sugars, amino acids and drug excipients were reported. The results obtained by the proposed electrodes were also applied successfully to the determination of the drug in its pharmaceutical preparations and biological fluids.     

Direct Determination of Azathioprine in Human Fluids and Pharmaceutical Formulation Using Flow Injection Chemiluminescence Analysis

A simple, sensitive and inexpensive flow injection chemiluminescence method for the determination of azathioprine had been discovered. It was based on the fact that the weak chemiluminescent reaction of cerium(IV) with azathioprine in acidic medium, which was enhanced by the addition of rhodamine 6G. A lot of optimized experimental conditions had been studied in detail. The CL intensity was linearly related to the concentration of azathioprine in the range of 0.1–10.0 μM and the detection limit was 45.0 nM (3σ). The relative standard deviation (RSD) for the technique was 2.1% (n = 11). The method had high selectivity, sensitivity and good repeatability. The proposed method had been triumphantly applied to the determination of azathioprine in human fluids and pharmaceutical formulation with satisfactory results.     

Syntheses and Structures of Na2Mg3(OH)2(SO4)3·4H2O and K2Mg3(OH)2(SO4)3·2H2O

The crystal structures of Na₂Mg₃(OH)₂(SO₄)₃ · 4H₂O and K₂Mg₃(OH)₂(SO₄)₃ · 2H₂O, were determined from conventional laboratory X‐ray powder diffraction data. Synthesis and crystal growth were made by mixing alkali metal sulfate, magnesium sulfate hydrate, and magnesium oxide with small amounts of water followed by heating at 150 °C. The compounds crystallize in space group Cmc2₁ (No. 36) with lattice parameters of a = 19.7351(3), b = 7.2228(2), c = 10.0285(2) Å for the sodium and a = 17.9427(2), b = 7.5184(1), c = 9.7945(1) Å for the potassium sample. The crystal structure consists of a linked MgO₆–SO₄ layered network, where the space between the layers is filled with either potassium (K⁺) or Na⁺‐2H₂O units. The potassium‐bearing structure is isostructural to K₂Co₃(OH)₂(SO₄)₃ · 2(H₂O). The sodium compound has a similar crystal structure, where the bigger potassium ion is replaced by sodium ions and twice as many water molecules. Geometry optimization of the hydrogen positions were made with an empirical energy code.     

鲁米诺-过氧化氢体系流动注射化学发光法测定维生素B4

维生素B4(VB4),又名磷酸腺嘌呤。它是核酸的组成成分,在体内参与RNA和DNA的合成。传统测定嘌呤类的方法是利用其在260 nm附近有最大吸收的性质,用紫外分光光度法定量[1],但此方法灵敏度不高。已报道的测定维生素B4的方法还有磷光法[2]、高效液相色谱法[3]、极谱法[4]、伏安法[5     

Determination of Rifampicin by Peroxomonosulfate‐Cobalt(II) Chemiluminescence System

Rifampicin can enhance the chemiluminescence (CL) of peroxomonosulfate‐cobalt(II) system, and the CL intensity is strongly dependent on the rifampicin concentrations. Based on this phenomenon, a rapid and sensitive flow injection CL method was developed for the determination of rifampicin. The relative CL intensity was linear with the rifampicin concentration over the range of 5×10^?8 to 1×10^?6 g·mL^?1 (r=0.9991), the detection limit was 7×10^?9 g·mL^?1 (S/N=3), and the relative standard deviation was 2.7% for 6×10^?7 g·mL^?1 rifampicin (n=11). Furthermore, this method was successfully applied to the determination of rifampicin in real eye drop and capsules sample.