A flow injection chemiluminescence system for the determination of isoniazid

A chemiluminescence (CL) flow system is described for the determination of isoniazid based on its enhancement on the chemiluminescence (CL) emission produced upon mixing a hexacyanoferrate(III) solution with an alkaline luminol solution. The system responds linearly to isoniazid concentration in the range 0-1 mg/L with a detection limit (3sigma) of 0.03 microg/L, relative standard deviation (RSD) of 1.2% for 0.1 mg/L isoniazid (n = 11). The system has been successfully applied to the determination of isoniazid in pharmaceutical preparations.     

A chemiluminescence flow injection system for nitrite ion determination

A chemiluminescence system is described for the determination of nitrite ion based on new designs for an ozone generator, liquid-gas separator and chemiluminescence reaction cell. The method is based on the gas-phase chemiluminescence reaction between ozone and nitric oxide, which is generated from the reduction of nitrite with iodide in sulfuric acid solution. The efficiency of the system was evaluated by investigation of the analytical performance characteristics of the system for nitrite determination in batch and flow injection procedures. Under optimal conditions, the chemiluminescence response of the system was linear against the nitrite concentration over the range 1 to 1 × 10⁴ ng ml^?1 in the batch procedure and 10 to 5 × 10³ ng ml^?1 in the flow injection procedure, with detection limits of 1 and 10 ng ml^?1, respectively. The method is highly selective and allows for the determination of nitrite in the presence of high concentrations of several cationic, anionic and nitrogen containing species. It has been successfully applied to the analysis of nitrite in natural water and soil extracts.     

N-bromosuccinimide-fluorescein system for the determination of protein by flow injection chemiluminescence

A method for flow injection with chemiluminescence (CL) detection has been developed for the determination of proteins. It is based on the luminescence of the N-bromosuccinimide-fluorescein-protein system, where fluorescein is used as an energy transfer reagent in alkaline medium. The CL of the system is strongly enhanced by hexadecyl trimethyl ammonium bromide. Optimum conditions and possible mechanisms have been investigated. Under optimum experimental conditions, the linear range is from 0.4 to 40 µg·mL^?1 for egg albumin, 0.2 to 20 µg·mL^?1 for bovine serum albumin, and from 1 to 100 µg·mL^?1 for bovine hemoglobin. The detection limits are 37, 62, and 240 ng·mL^?1, respectively.     

A novel sensitized chemiluminescence flow injection system for the determination of adriamycin and mitomycin

A novel chemiluminescence (CL) method was established for two anticancer drugs, adriamycin (ADM) and mitomycin (MMC), based on potassium permanganate oxidation in the presence of formaldehyde. The sensitized CL emission mechanism was developed by comparing the fluorescence emission with CL spectra. Illuminant was the singlet state bi-molecule oxygen, ¹O₂ ¹O₂ (¹Δ_g ¹Δ_g), from ¹O₂ (¹Δ_g) which was produced in the reaction system, and emitted CL spectra at 639 nm or 649 nm. The presence of formaldehyde may accelerate the generation of ¹O₂ (¹Δ_g) and sensitized CL emission. The optimum conditions for CL emission were investigated and optimized. The relationships between the relative CL intensity and the concentration of the studied analytes found to be linear. The detection limit was 3 × 10^?8 g ml^?1 for ADM and 3 × 10^?9 g ml^?1 for MMC. The relative standard deviations are 2.2% and 1.8% for determinations of ADM at 2.0 × 10^?6 g ml^?1 and MMC at 2.0 × 10^?7 g ml^?1, respectively. The proposed sensitized CL system was successfully applied to the determination of ADM and MMC in their injections with satisfactory results.     

Flow injection chemiluminescence determination of isoniazid with electrogenerated hypochlorite

A flow-injection chemiluminescence method for the determination of isoniazid based on the sensitizing effect of isoniazid on the chemiluminescence generating luminol-hypochlorite reaction is described. The hypochlorite was electrogenerated on-line by constant current electrolysis, thus, eliminating instability of hypochlorite solution prepared from commercially available sodium hypochlorite. The calibration graph is linear in the range 1 × 10^–8 to 1 × 10^–6 g mL^–1, and the detection limit is 6 × 10^–9 g mL^–1. The relative standard deviation for determination of 5 × 10^–8 g mL^–1 is 2.8%. The proposed method has been successfully applied to the determination of isoniazid in pharmaceutical preparations.     

Flow injection chemiluminescence determination of isoniazid with electrogenerated hypochlorite

A flow-injection chemiluminescence method for the determination of isoniazid based on the sensitizing effect of isoniazid on the chemiluminescence generating luminol-hypochlorite reaction is described. The hypochlorite was electrogenerated on-line by constant current electrolysis, thus, eliminating instability of hypochlorite solution prepared from commercially available sodium hypochlorite. The calibration graph is linear in the range 1 × 10^–8 to 1 × 10^–6 g mL^–1, and the detection limit is 6 × 10^–9 g mL^–1. The relative standard deviation for determination of 5 × 10^–8 g mL^–1 is 2.8%. The proposed method has been successfully applied to the determination of isoniazid in pharmaceutical preparations. Reveived: 2 May 1998 / Revised: 27 July 1998 / Accepted: 7 August 1998     

Ultrasound-enhanced flow injection chemiluminescence for determination of hydrogen peroxide

A novel ultrasonic flow injection chemiluminescence (FI-CL) manifold for determining hydrogen peroxide (H2O2) has been designed and evaluated. Chemiluminescence obtained from the luminol-H2O2-cobalt(II) reaction was enhanced by applying 120 W of ultrasound for a period of 4 s to the reaction coil in the FI-CL system and this enhancement was verified by comparison with an identical manifold without ultrasound. The system was developed for determining ultra-trace levels of H2O2 and a calibration curve was obtained with a linear portion over the range of 10-200 nmol L(-1) H2O2 (correlation coefficient 0.9945). The detection limit (3sigma) and the quantification limit (LOQ) were found to be 1 x 10(-9) and 3.3 x 10(-9) mol L(-1) respectively and the relative standard deviation was 1.37% for 2 x 10(-7) mol L(-1) H2O2 (n = 10). The method was applied to the determination of trace amounts of H2O2 in purified water and natural water samples without any special pre-treatments.     

Flow injection chemiluminescence determination of isoniazid using luminol and silver nanoparticles

The effect of silver colloidal nanoparticles (AgNPs) on the luminol–isoniazid system was investigated. It was found that AgNPs could act as a nanocatalyst on the luminol–isoniazid system to generate chemiluminescence (CL). The CL emission spectrum of the luminol–isoniazid–AgNPs system showed a peak with a maximum at 425 nm. It was suggested that the luminophor species was the excited state 3-aminophthalate. The reduction of dissolved O₂ to H₂O₂ by isoniazid and decomposition of H₂O₂ to the oxygen-related radicals were attributed to the catalytic effect of AgNPs. Under optimized conditions, the CL signal intensity was linear with the isoniazid concentration in the range of 10–1000 ng mL^{− 1}, with the correlation coefficient of 0.9996. The limit of detection was 2.7 ng mL^{− 1} isoniazid. The relative standard deviations for seven repeated measurements of 60 and 200 ng mL^{− 1} isoniazid were 1.4 and 2.4%, respectively. The effect of potent interfering compounds on the CL signal intensity of the proposed luminol–isoniazid–AgNPs system was investigated. The proposed method was successfully applied to the determination of isoniazid in a pharmaceutical sample.     

The determination of sulfite in a flow injection system with chemiluminescence detection

The emission produced by sulfite on oxidation by permanganate in acidic solution in the presence of riboflavin phosphate or brilliant sulfaflavine is used to determine 0.9–35 ng of sulfite. Only sulfide and thiosulfate also give emissions.     

快速化学发光联用流动注射技术测定西咪替丁

在NaOH-NaHCO3介质中,铁氰化钾氧化西咪替丁产生快速化学发光反应,0.5 s后发光达到最大,2 s后迅速衰减至零。本文结合流动注射技术,建立了一种化学发光测定西咪替丁的新方法。针对这一快速发光反应,设计了与之相应的管路系统和最短的反应管道来捕捉最大化学发光信号,发光强度与西咪替丁质量浓度在5×10-7~1×10-4g/mL范围内呈线性关系,检出限为1.1×10-7g/mL。对5×10-6g/mL西咪替丁进行11次平行测定,相对标准偏差为1.8%。本法已用于西咪替丁片剂的测定。     

纳米银增敏鲁米诺液相化学发光分析法测定4-乙酰氨基酚的研究

研究发现在碱性条件下,纳米银对鲁米诺-铁氰化钾液相化学发光体系发光信号具有明显的增敏作用,而4-乙酰氨基酚对该体系具有强烈的抑制作用。结合流动注射技术,建立了流动注射化学发光分析法测定对乙酰氨基酚的新方法。该方法测定对乙酰氨基酚的线性范围为9.0×10-12～1.0×10-10g/mL(0.9947)和1.0×10-1...     

反相流动注射胶束增敏化学发光分析法测定硝苯地平

基于胶束介质中硝苯地平对碱性鲁米诺-过氧化氢化学发光体系的增敏作用,结合反相流动注射技术,建立了流动注射化学发光分析法测定硝苯地平的新方法.硝苯地平浓度在3.5×10-10～4.0×10-8 g·mL-1范围内时,化学发光强度与硝苯地平的浓度呈良好的线性关系,其相对标准偏差为1.4%(n=11,c=3.5×10-9 g...     

NBS-二氯荧光素化学发光体系测定西索米星

在碱性奈件下，西索米星被NBS（N-溴代琥珀酰亚胺）氧化，其能量可激发共存的二氯荧光素（DCF）而产生化学发光，发光强度与西索米星的质量浓度在一定范围内呈良好的线性关系，基于此，结合流动注射技术，建立了一种直接测定西索米星的化学发光新方法。该方法具有较高的灵敏度，检出限为73μg／L（IUPAC），线性范围为0．1～10mg／L，对5．0mg／L西索米星平行测定11次，其相对标准偏差为2．3％。已用于针剂中西索米星的测定。     

流动注射电化学发光分析法测定甲磺酸培氟沙星

甲磺酸培氟沙星为第三代喹诺酮类抗菌药,疗效好,抗菌谱更广,且对青霉素、头孢菌素、氨基苷类耐药菌株均有效,在临床上被广泛使用。本文发现,在Na2CO3-NaHCO3碱性溶液中,1．40V电解电位下,鲁米诺在铂电极上的弱电化学发光信号可以被甲磺酸培氟沙星强烈地增敏,据此建立了甲磺酸培氟沙星的流动注射电化学发光分析方法。     

流动注射阻抑化学发光法测定己烯雌酚

基于在碱性介质中,己烯雌酚对N-溴代丁二酰亚胺-鲁米诺化学发光体系的阻抑作用,建立了测定己烯雌酚的流动注射化学发光分析新方法,探讨并优化了流动注射化学发光的分析条件。该方法测定己烯雌酚的线性范围为1.5×10-8~2.6×10-7g/mL,检出限为5.0×10-9g/mL,对1.0×10-7g/mL的己烯雌酚标准溶液进行11次测定,相对标准偏差为2.6%。并应用于饲料、己烯雌酚片剂中的己烯雌酚的测定。     

Rapid determination of subnanogram urapidil using flow injection enhancement chemiluminescence

A sensitive flow-injection (FI) chemiluminescence (CL) for the determination of urapidil is described in this paper. It is based on the enhancement effect of urapidil on the CL reaction between luminol and hydrogen peroxide. The increment of CL intensity is proportional to the concentration of urapidil in the range 0.1−10 ng/mL (R ²=0.9986), with a detection limit (3σ) of 0.03 ng/mL. The whole process, at a flow rate of 2.0 mL/min, including sampling and washing, could be completed in 0.5 min, and the relative standard deviation (RSD) at the concentration of 0.1, 1.0, and 10.0 ng/mL was less than 3.0% (n = 5). The proposed method has been successfully applied for the determination of urapidil in pharmaceutical preparation, human urine, and serum. The text was submitted by the authors in English.     

流动注射化学发光法测定有机磷农药残留量

基于K2S2O8在紫外光催化下可将有机磷消解为正磷酸盐,而正磷酸盐在酸性条件下可与钼酸盐、钒酸盐形成具有氧化性的磷钼钒杂多酸,其可直接氧化碱性鲁米诺产生强的化学发光,本文结合流动注射技术,提出了一种测定有机磷农药残留量的化学发光新方法。其线性范围为1.0×10-9~1.0×10-5g/mL,检出限为8.0×10-10g/mL。对2.0×10-7g/mL的磷进行11次平行测定,其RSD为4.8%。并分别测定了3种有机磷农药。     

A simple flow injection system with bead injection for trace iron determination

A simple and low cost flow injection (FI) system with bead injection (BI) was developed for determination of low concentration (mumol l(-1)) of iron in water samples. Chelex-100 chelating resin beads, trapped in a jet ring cell, were employed. The intensity of red complex of 1,10-phenanthroline with Fe(2+) was monitored using colorimetric detector with a LED green light source. Amount of total Fe (Fe(2+) and Fe(3+)) and Fe(2+) can be evaluated by with and without reduction of Fe(3+) using ascorbic acid. Lowest detectable levels of Fe(2+) were 0.90 and 0.45 mumol l(-1) for sample loading time of 3 and 5 min, respectively. Working range was up to 3.90 mumol l(-1) using 0.3% w/v 1, 10-phenanthroline. Percent recoveries of spiked water samples (0.90-2.33 mumol l(-1) of Fe(2+)) were 100-110%.     

A comparison of spectrophotometric and chemiluminescence methods for the determination of blood glucose by flow injection analysis

A flow-injection manifold for the determination of plasma glucose (0–25 mM), incorporating a dialysis unit and a wall-coated enzyme reactor, is described. Spectrophotometric and chemiluminescence methods of detection are compared in terms of precision, accuracy, sample throughput, cost and reliability, and the results obtained from both methods are compared with those obtained from an electrochemical star analyser.     

K3Fe(CN)6-钙黄绿素体系后化学发光反应测定盐酸氯丙嗪

发现了盐酸氯丙嗪在K3Fe(CN)6-钙黄绿素化学发光反应体系中的后化学发光反应,优化了反应条件,建立了一种利用后化学发光反应测定盐酸氯丙嗪的流动注射化学发光分析法.方法的检出限为3×10-8/mL,相对标准偏差为2.0%(2.0×10-6 g/mL盐酸氯丙嗪,n=11),线性范围为1.0×10-7～1.0×10-5 g/mL.此法已用于盐酸氯丙嗪片剂中盐酸氯丙嗪含量的测定,结果与药典方法测定值一致.