Flow-injection enhanced chemiluminescence method for determination of ciprofloxacin in pharmaceutical preparations and biological fluids

A novel rapid and sensitive analytical method, enhanced chemiluminescence with flow-injection sampling, is described for determination of ciprofloxacin. The method is based on the chemiluminescence reaction of the potassium permanganate–sodium thiosulfate–ciprofloxacin system. An enhanced chemiluminescence reaction was developed, and optimum conditions for CL emission were investigated. The chemiluminescence intensity was linearly dependent on ciprofloxacin concentration in the range 1.0×10⁻⁸–1.0×10⁻⁵ g mL⁻¹. The detection limit was 4×10⁻⁹ g mL⁻¹. The relative standard deviation was 1.8% for eleven measurements of 2.0×10⁻⁷ g mL⁻¹ ciprofloxacin standard solution. The new method enables simple, sensitive, and rapid determination of ciprofloxacin and has been successfully used for determination of ciprofloxacin in biological fluids and in ciprofloxacin hydrochloride tablet and injection.     

In vitro detecting ultra-trace novalgin in medicine and human urine by chemiluminescence

A sensitive chemilumimetric method for the determination of novalgin at the sub-nanogram level is presented. The method is based on immobilized luminol and dichromate chemiluminescence detection coupled with a flow injection system. The intensity of the chemiluminescence can be strongly inhibited by novalgin and the decrement of CL intensity was linear with the logarithm of novalgin concentration in the range of 5.0×10⁻¹¹ to 5.0×10⁻⁸ g ml⁻¹. The detection limit is 2.0×10⁻¹¹ g ml⁻¹ (3σ) and the relative standard deviation is 2.57% (n=5) for a 1.0×10⁻¹⁰ g ml⁻¹ novalgin sample. A typical analytical procedure, including sampling and washing, could be performed in 1 min at a flow rate of 2.0 ml min⁻¹, giving a throughput of 60 h⁻¹. The proposed procedure was applied successfully in pharmaceutical preparations and furthermore the monitoring of novalgin in human urine without any pre-treatment process during 10 h. It was found that the novalgin concentration reached its maximum after orally administrated for about 4 h, and the novalgin metabolism ratio in 10 h was 10.83% in the body of volunteers. The flow system offered reagentless procedures and remarkable stability in determination of novalgin, and could be easily reused over 600 times.     

Simple, rapid and sensitive spectrofluorimetric determination of diflunisal in serum and urine based on its ternary complex with terbium and EDTA

A very simple, rapid and highly sensitive fluorimetric method for the determination of diflunisal in serum and urine is described. The method is based on the formation of a ternary complex between diflunisal, Tb³⁺ and EDTA in alkaline aqueous solutions. This complex exhibits very intense terbium ion luminescence with a main emission maximum at 546 nm when excited at 284 nm. Optimum conditions for the complex formation have been investigated. The detection limit for diflunisal is 2.4 μg 1⁻¹, while the range of application is 0.01–6.00 mg 1⁻¹. The method has been successfully applied for the determination of diflunisal in untreated human serum and urine samples. Analytical recoveries from serum and urine samples spiked with diflunisal were in the ranges of 96.8–101.2% and 98.0–102.0%, respectively.     

铽-妥舒沙星的敏化化学发光研究

镧系离子Tb3 能极大增强TSLX Ce(Ⅳ ) Na2 SO3 体系的化学发光强度 ,据此提出了妥舒沙星的敏化化学发光测定妥舒沙星 (TSLX)的新方法。在选定的最佳实验条件下 ,TSLX的浓度在 8.0× 1 0 -9～ 1 .0× 1 0 -5mol L-1 范围内与化学发光强度呈良好的线性关系 ,检出限为 5 .6× 1 0 -1 0 mol L ,对 1 .0× 1 0 -7mol L的TSLX标准溶液进行 1 1次平行测定 ,相对标准偏差为 1 .3 %。     

诺氟沙星的铽敏化化学发光法研究与应用

本文根据 Tb3+能显著增强 Ce ( ) - SO2 - 3- NFLX体系的化学发光 ,建立了流动注射铽敏化化学发光测定诺氟沙星的新方法。本法的线性范围为 9.0× 1 0 - 9～ 1 .0× 1 0 - 6 mol/L,检出限为 4.5× 1 0 - 11mol/L。利用该法测定了诺氟沙星胶囊中诺氟沙星的含量 ,并对血清和尿样进行了回收率测定 ,回收率在 1 0 0 .4%～ 1 0 5 .7% ,结果令人满意。     

Lanthanide sensitized chemiluminescence determination of grepafloxacin in tablets and human urine

A flow-injection chemiluminescence (CL) method, based on the luminescent properties of the Ce(IV)-Na₂SO₃-lanthanide(III)-grepafloxacin system, was developed for the determination of grepafloxacin {1-cyclopropyl-6-fluoro-1,4-dihydro-5-methyl-7-(3-methyl-1-piperazinyl)-4-oxo-3-quinolinecarboxylic acid}. La(III), Tb(III), and Eu(III) ions were tested as possible chemiluminescence sensitizers. The best results were achieved when Tb(III) was used as lanthanide ion, so the technique was optimised working with this ion. Under the optimum experimental conditions, the linear range was 0.05-2.00 μg ml⁻¹ grepafloxacin, with a 0.01 μg ml⁻¹ detection limit and 2.0% relative standard deviation (n=10). The proposed procedure has been applied to the determination of grepafloxacin in tablets and spiked human urine.     

流动注射化学发光法测定痕量NO_2~-的研究与应用

Based on the principle of the reaction of NO2-with I-and formation of I2 in HCl solution,and the chemiluminescence(CL) reaction between luminol and I2 in an alkaline medium.A fairly sensitive,simple and rapid flow-injection analysis-chemiluminescence method for the determina-tion of trace nitrite with the luminal-I——NO2-coupling luminescence system has been developed.Experiment conditions of flow-injection analysis are optimized.When satisfying the condition that Luminol as 4.0×10-4 mol/L,0.7 % KI,0.04 mol/...     

A study of the chemiluminescence behavior of myoglobin with luminol and its analytical applications

A chemiluminescence signal at 425 nm was observed when ferric state myoglobin was mixed with luminol in alkaline medium. Because the signal was remarkably enhanced in the presence of Fe(CN)₆ ^4–, analytical applications were investigated in a flow-injection system. The increase in chemiluminescence was linearly dependent on myoglobin concentration in the range 0.1 to 100 nmol L^–1, and the limit of detection was 0.04 nmol L^–1 with relative standard deviation 3.2% (3). It was also found that binding of Mb with the ligands CN^–, SCN^–, and F^– significantly inhibited the chemiluminescence reaction. The linear dynamic ranges for the ligands were 1.0–300.0, 0.1–3.0, and 0.5–100.0 nmol L^–1, and the limits of detection (S/N=3) 0.4, 0.04, and 0.2 nmol L^–1, for F^–, CN^–, and SCN^–, respectively. The relative standard deviations were 5.32%, 6.13%, and 3.38% for 0.1 nmol L^–1 CN^–, 0.5 nmol L^–1 SCN^–, and 1.0 nmol L^–1 F^–, respectively. At a flow rate of 2.0 mL min^–1 the assay could be accomplished in 1 min, including sampling and washing. The method has been successfully applied to the determination of myoglobin in human urine and F^– in water samples. A possible mechanism of chemiluminescence production by myoglobin and luminol is presented.     

Study on the chemiluminescence behavior of bovine serum albumin with luminol and its analytical application

In this paper, the luminescence behavior of bovine serum albumin (BSA) and luminol was first studied by flow injection chemiluminescence (CL). It was found that the hyperchromic effect of luminol in the presence of BSA led to the acceleration of the electrons transferring rate of excited 3-aminophthalate, which greatly enhanced the CL intensity of luminol/dissolved oxygen reaction. The increments of CL intensity were proportional to the concentrations of BSA with a linear range from 0.01 to 7 nmol L(-1). It was also found that azithromycin could inhibit the CL intensity of luminol/BSA reaction. The decrements of CL intensity were logarithm over the concentrations of azithromycin ranging from 0.1 to 700 ng mL(-1). At a flow rate of 2.0 mL min(-1), a complete analytical process, which included sampling and washing, could be performed within 30s with relative standard deviations of less than 3.1%. This proposed method was successfully applied in assaying azithromycin in pharmaceutical and human serum samples with recoveries from 91.0 to 104.3%. The possible luminescence mechanism of luminol/BSA/azithromycin reaction was discussed in detail by CL, UV and fluorescence methods.     

流动注射电化学发光分析法测定维生素B1及在尿液分析中的应用

将在线恒电流电解产生ClO-与Luminol构成了较强的化学发光体系,基于维生素B1对该化学发光体系有抑制作用,结合流动注射技术,建立了测定维生素B1的流动注射电化学发光新方法,并把它应用于尿液分析中. 该方法在维生素B1的浓度为1.0×10-10～1.0×10-8 mmol/mL之间分段回归,呈良好的线性,检出限达到5.0×10-11 mmol/mL.     

Flow-injection determination of 3-hdroxybutyrate in serum with an immobilized 3-hydroxybutyrate dehydrogenase reactor and chemiluminescence detection

A flow-injection system for the determination of 3-hydroxybutyrate in serum is described. 3-Hydroxybutyrate dehydrogenase is immobilized on poly(vinyl alcohol) beads and incorporated in a flow-injection system. 1-Methoxy-5-methylphenazinium methylsulphate reacts with enzymatically generated NADH to give H₂O₂, which is detected chemiluminometrically with the reaction of luminol and hexacynoferrate(III). Serum is diluted and filtered through an ultrafiltration membrane. The system responds linearly to injected samples (80 μl) in the concentration range 0.5–300 μM; the detection limit is 0.1 μM. The within-day relative standard deviation (n = 90) for 58 μM 3-hydroxybutyrate in serum is 0.8%. The maximum throughout is 20 samples per hour. The immobilized enzyme is stable for at least 1 month.     

流动注射化学发光法测定己烯雌酚

基于己烯雌酚对鲁米诺与高碘酸钾在碱性介质中反应产生的化学发光信号有较强的增敏作用,建立了测定己烯雌酚的流动注射化学发光分析法。己烯雌酚质量浓度在13．4—1340μg／L范围内与化学发光强度呈良好的线性关系,检出限（3d）为4μg／L;对26．8μg／L己烯雌酚进行11次平行测定,相对标准偏差（RSD）为1．4％。该法已用于药物制剂中己烯雌酚的测定。     

Post-column terbium complexation and sensitized fluorescence detection for the determination of norepinephrine, epinephrine and dopamine using high-performance liquid chromatography

Terbium sensitized fluorescence was used as a post-column detection system to develop a simple, sensitive and rapid high-performance liquid chromatographic method for the simultaneous determination of catecholamines norepinephrine (NE), epinephrine (E) and dopamine (DA).Catecholamines were separated by an ion-pair reversed-phase chromatography on a BDS-Hypersil analytical column with a mobile phase of methanol and 50 mmol l⁻¹ acetate buffer (pH 4.7) containing 1.1 mmol l⁻¹ SOS and 0.11 mmol l⁻¹ EDTA (15+85 v/v).Catecholamines and the internal standard (3,4-dihydroxybenzylamine, DHBA) were post-column derivatized by the addition to the eluent of an alkaline solution containing a stoichiometric mixture of terbium(III) chloride and EDTA. Fluorescence detection (λ_ex=300 nm, λ_em=545 nm) is based on the sensitization of terbium ion fluorescence after complexation with catecholamines.The chemical compatibility between the eluent and the post-column reagent was studied and the analytical characteristics of the method were established. Detection limits found were 1.0×10⁻⁸, 4.0×10⁻⁸ and 7.0×10⁻⁸ mol l⁻¹ for NE, E and DA, respectively. The method has been successfully applied to the determination of catecholamines in urine samples after solid-phase extraction (SPE) pre-treatment. Recoveries from urine spiked with NE (4.0×10⁻⁷, 2.0×10⁻⁶ and 4.0×10⁻⁶ mol l⁻¹), E (8.2×10⁻⁸, 4.1×10⁻⁷ and 8.2×10⁻⁷ mol l⁻¹) and DA (1.0×10⁻⁶, 5.0×10⁻⁶ and 1.0×10⁻⁵ mol l⁻¹) varied from 98 to 100% (mean=99.3%), from 106 to 107% (mean=106.3%) and from 98 to 101% (mean=99.3%), respectively. The between-run precision (relative standard deviation, R.S.D.) for the method for three urine samples at different concentration levels of each catecholamine varied from 3.6 to 7.0%.     

CdTe nanocrystals sensitized chemiluminescence and the analytical application

It was found that the mixing of CdTe semiconductor nanocrystals (NCs) with luminol in the presence of KMnO₄ can induce a great sensitized effect on chemiluminescence (CL) emission. When the concentration of luminol, KMnO₄ and NaOH were fixed at 1 μM, 1 μM and 0.05 M, respectively, the most excellent performance can be obtained for the CdTe NCs sensitized CL. By means of CL and photoluminescence spectra, we suppose the enhanced CL signals resulted from the accelerated luminol CL induced by the oxidized species of CdTe NCs. Based on the finding, using thioglycolic acid-capped CdTe NCs as label and immunoglobulin G (IgG) as a model analyte, a CL immunoassay protocol for IgG content detection was developed. The strong inhibition effect of phenol compounds on luminol-KMnO₄-CdTe NCs CL system was also observed. All these findings demonstrated the possibility of semiconductor nanocrystals induced chemiluminescence to be utilized for more practical applications.     

Flow-injection analysis of two fluoquinolones by the sensitizing effect of terbium(III) on chemiluminescence of the potassium permanganate-sodium sulfite system

A simple, rapid and sensitive method for the determination of two fluoquinolones (FQs), enoxacin (ENX) and ofloxacin (OFLX) is described by using flow injection analysis with potassium permanganate-sodium sulfite chemiluminescence detection. The calibration graphs for ENX and OFLX are linear in the range of 8.0×10⁻¹⁰-1.0×10⁻⁵ and 1.0×10⁻⁹-1.0×10⁻⁶ mol l⁻¹, respectively. The 3σ limits of detection are 2.4×10⁻¹⁰ mol l⁻¹ for ENX and 5.6×10⁻¹⁰ mol l⁻¹ for OFLX. The method is applied satisfactorily to the determination of the two FQs in dosage form and urine sample. The possible mechanism is also proposed.     

流动注射化学发光法测定褪黑素

在强碱性介质中,铁氰化钾可直接氧化褪黑素产生化学发光。基于此,建立了一种测定褪黑素的流动注射化学发光分析方法。线性范围为1.9×10-6~2.3×10-4g/mL,检出限为5×10-7g/mL,该法已用于药物中褪黑素的测定。     

流动注射化学发光法测定阿莫西林

在碱性介质中 ,阿莫西林抗生素对鲁米诺 KMnO4化学发光反应有增敏作用 ,据此建立了微量快速测定阿莫西林的流动注射化学发光分析法。该法线性范围为 1 .0× 1 0 -7～ 5 .0× 1 0 -5g mL ,检出限为 3.0× 1 0 -8g mL ;对 1 .0× 1 0 -6g mL阿莫西林 1 1次平行测定 ,其相对标准偏差为 1 .7%。此法已用于阿莫西林胶囊中阿莫西林的测定。     

流动注射化学发光法测定盐酸氟桂利嗪

在酸性条件下,盐酸氟桂利嗪与KMnO4反应可产生弱的化学发光,甲醛的存在对这一反应的化学发光强度具有增强作用。据此,优化了化学发光反应条件,建立了测定盐酸氟桂利嗪的流动注射化学发光分析法。该方法测定盐酸氟桂利嗪的线性范围为8.0×10-7~8.0×10-5g/mL,检出限为8×10-7g/mL,对1.0×10-5g/mL盐酸氟桂利嗪标准溶液进行11次平行测定的相对标准偏差为2.2%。方法已用于盐酸氟桂利嗪胶囊中盐酸氟桂利嗪的测定。     

流动注射-化学发光法测定片剂中氨基比林

采用流动注射技术 ,研究了氨基比林 -高锰酸钾 -连二亚硫酸钠体系的化学发光行为。对影响化学发光强度的诸因素进行了实验探讨 ,建立了化学发光法测定片剂中氨基比林的新方法。方法的检出限为 6× 1 0 -8g/m L,线性范围为2 .0× 1 0 -7～ 8.0× 1 0 -5g/m L。对浓度为 4.0× 1 0 -6g/m L的氨基比林的相对标准偏差为 1 .8%     

Sensitive determination of captopril by flow injection analysis with chemiluminescence detection based on the enhancement of the luminol reaction

This work reports a novel flow injection (FI) method for the determination of captopril, 1-[(2S)-3-mercapto-2-methylpropionyl]-l-proline (CPL), based on the enhancement CPL affords on the chemiluminescence (CL) reaction between luminol and hydrogen peroxide. For this purpose alkaline luminol and hydrogen peroxide solutions were mixed online, the sample containing CPL was injected into an aqueous carrier stream, mixed with the luminol-hydrogen peroxide stream and pumped into a glass flow cell positioned in front of a photomultiplier tube (PMT). The increase in the CL intensity was recorded in the form of FI peaks, the height of which was related to the CPL mass concentration in the sample. Different chemical and instrumental parameters affecting the CL response were investigated. Under the selected conditions, the log-log calibration curve was linear in the range 5-5000 μg l⁻¹ of CPL, the limit of detection was 2 μg l⁻¹ (at the 3σ level), the R.S.D., s_r was 3.1% at the 100 μg l⁻¹ level (n=8) and the sampling rate was 180 injections h⁻¹. The method was applied to the determination of CPL in pharmaceutical formulations with recoveries in the range 100±3%.