共查询到20条相似文献,搜索用时 15 毫秒
1.
Jiachu Huang Chengxiao Zhang Zhujun Zhang 《Analytical and bioanalytical chemistry》1999,363(1):126-128
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. 相似文献
2.
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. 相似文献
3.
A direct chemiluminescence method for the determination of nucleic acids has been developed based on the enhancement of
nucleic acids on the chemiluminescence light emission of the reaction between Ru(phen)3
2+(phen = 1,10-phenanthroline) and Ce(IV). Under the optimum conditions, the calibration graphs are linear in the range of 5.0
× 10–8–5.0 × 10–5 g/mL for calf thymus DNA, 8.0 × 10–8–5.0 × 10–5 g/mL for fish sperm DNA and 1.0 × 10–7–3.0 × 10–5 g/mL for yeast RNA, respectively. The limits of detection are 1.0 × 10–8 g/mL for calf thymus DNA, 3.1 × 10–8 g/mL for fish sperm DNA and 5.2 × 10–8 g/mL for yeast RNA, respectively. The final procedure allows the successful determination of calf thymus DNA, fish sperm
DNA and yeast RNA in six synthetic samples. This method is simple, rapid and specific.
Received: 22 January 1999 / Revised: 29 April 1999 / Accepted: 3 May 1999 相似文献
4.
In this article, novel chemiluminescence mechanisms between norfloxacin and cerium(IV) in an acidic medium were studied. Chemiluminescence
spectra of the present system were recorded observing three maximum emissions at about 475 nm, 550 nm, and 620 nm, respectively.
The results indicate that the chemiluminescence peaks located at 475 nm and 620 nm can be ascribed to the emission of a singlet
oxygen, while the chemiluminescence emission at 550 nm occurred in course of the reaction between acidic cerium(IV) and the
phenolic intermediate. Under optimum conditions, the chemiluminescence intensity was linear with the concentration of norfloxacin
over the range of 2.0 × 10−8−1.0 × 10−5 g mL−1 and the detection limit of 1.0 × 10−8 g mL−1 (S/N = 3). The relative standard deviation was 1.94 % for a 4.0 × 10−7 g mL−1 norfloxacin solution considering eleven repeated measurements. The present chemiluminescence system was successfully applied
in the determination of norfloxacin in pharmaceutical preparations and concentration-time profiles in urine. 相似文献
5.
Manliang Feng Guofang Zhang Zhujun Zhang 《Fresenius' Journal of Analytical Chemistry》1999,363(3):320-322
Chemiluminescence was observed by mixing acidic potassium permanganate solution with pyruvate in the presence of quinine.
A new simplified method for pyruvate determination based on this phenomenon was established. The chemiluminescence intensity
is a linear function of the concentration of pyruvate in the range of 2 × 10–6 to 1 × 10–3 g/mL with a detection limit of 0.8 μg/mL and a relative standard deviation of less than 2.3%. The method has been successfully
used to determine pyruvate in serum.
Received: 3 April 1998 / Revised: 20 July 1998 / Accepted: 17 September 1998 相似文献
6.
Andreas Rahm Evgeni M. Kaidashev Heidemarie Schmidt Mariana Diaconu Andreas Pöppl Rolf Böttcher Christoph Meinecke Tilman Butz Michael Lorenz Marius Grundmann 《Mikrochimica acta》2006,153(1-2):21-25
A flow injection chemiluminescence method is proposed for the determination of cobalt, based on the strong catalytic effect
of Cobalt(II) (1,10-phenanthroline)3 complex on the lucigenin-periodate reaction in alkaline medium. Under the optimum experimental conditions, the chemiluminescence
signal responded linearly to the concentration of cobalt(II) in the 1.0 × 10−9–3.0 × 10−7 g mL−1 range with a detection limit of 4.4 × 10−10 g mL−1 cobalt(II). The relative standard deviation for the determination of 5.0 × 10−8 g mL−1 of cobalt was 2.3% in eleven replicated measurements. The method was successfully applied to the determination of cobalt(II)
in pharmaceutical preparations. 相似文献
7.
Feng QZ Zhao LX Yan W Ji F Wei YL Lin JM 《Analytical and bioanalytical chemistry》2008,391(3):1073-1079
Highly sensitive flow-injection chemiluminescence (CL) combined with molecularly imprinted solid-phase extraction (MISPE)
has been used for determination of 2,4-dichlorophenol (2,4-DCP) in water samples. The molecularly imprinted polymer (MIP)
for 2,4-DCP was prepared by non-covalent molecular imprinting methods, using 4-vinylpyridine (4-VP) and ethylene glycol dimethacrylate
(EGDMA) as the monomer and cross-linker, respectively. 2,4-DCP could be selectively adsorbed by the MIP and the adsorbed 2,4-DCP
was determined by its enhancing effect on the weak chemiluminescence reaction between potassium permanganate and luminol.
The enhanced CL intensity was linear in the range from 1 × 10−7 to 2 × 10−5g mL−1. The LOD (S/N = 3) was 1.8 × 10−8g mL−1, and the relative standard deviation (RSD) was 3.0% (n = 11) for 1.4 × 10−6g mL−1. The proposed method had been successfully applied to the determination of 2,4-DCP in river water.
Figure Effect of 4-VP content on the ultraviolet spectrum of 2,4-DCP in chloroform 相似文献
8.
A novel and simple chemiluminescence (CL) method has been developed and validated for determination of metformin. This method
is based on hydroxyl radical chemiluminescence—the hydroxyl radical generated by reaction of Cu(II) and hydrogen peroxide
oxidizes rhodamine B (RhB) to produce weak CL which can be enhanced by metformin. At the same time, metformin molecularly
imprinted polymer (MIP) was synthesized. After enrichment based on the selectivity of metformin-MIP, the CL method was successfully
applied to the determination of metformin in human serum. The linear range was from 1.0×10−8 to 1.0×10−6 g mL−1 and the detection limit was 4×10−9 g mL−1. The relative standard deviation at 2.0×10−7 g mL−1 by use of MIP was 3.67% (n=7). 相似文献
9.
S. M. Sultan Aladdin M. Almuaibed A. Townshend 《Fresenius' Journal of Analytical Chemistry》1998,362(1):167-169
A new flow injection chemiluminescence method for the assay of medazepam is explored. The method involves the use of permanganate
in sulfuric acid for the oxidation of medazepam with the emission of chemiluminescence detected by a photomultiplier tube.
A simplex procedure was employed for optimising the conditions for high sensitivity detection, which were found to be 1.03
× 10–3 mol L–1 permanganate, 0.153 mol L–1 sulfuric acid and 3.43 mL min–1 flow rate. The linear calibration range was 3.7 × 10–5 to 1.7 × 10–3 mol L–1. The detection limit (3σ) and the sample throughput were 1.85 × 10–5 mol L–1 and 100 per hour, respectively. The relative standard deviation for 5 replicate determinations of 1.9 × 10–4 mol L–1 medazepam was 0.15%. Common excipients (starch, glucose, maltose, lactose) used in pharmaceutical preparations had no effect.
Received: 2 February 1998 / Revised: 20 May 1998 / Accepted: 25 May 1998 相似文献
10.
A new chemiluminescence (CL) method combined with flow injection technique is described for the determination of Cr(III) and
total Cr. It is found that a strong CL signal is generated from the reaction of Cr(III), lucigenin and KIO4 in alkaline condition. The determination of total Cr is performed by pre-reduction of Cr(VI) to Cr(III) by using H2SO3. The CL intensity is linearly related to the concentration of Cr in the range 4.0 × 10−10–1.0 × 10−6 g mL−1. The detection limit (3s
b) is 1 × 10−10 g mL−1 Cr and the relative standard deviation is 1.9% (5.0 × 10−8 g mL−1 of Cr(III) solution, n = 11). The method was applied to the determination of Cr(III) and total Cr in water samples and compared satisfactorily with
the official method. 相似文献
11.
A novel chemiluminescence(CL) flow system for sulfite is described based on electrostatically immobilized luminol on an anion
exchange column. Sulfite is detected by the CL reaction with luminol bleeding from the column by hydrolysis. The calibration
graph is linear in the range 3 × 10–7 to 1 × 10–5 mol/L, and the detection limit is 1 × 10–7 mol/L. Interfering metal ions co-existing in sample solutions could be effectively eliminated on-line by an upstream cation
exchanger. A complete analysis could be performed in 1 min with a relative standard deviation of less than 5%. The system
could be reused for over 50 h and has been applied successfully to the determination of sulfur dioxide in air.
Received: 21 October 1997 / Revised: 23 February 1998 / Accepted: 26 February 1998 相似文献
12.
Spectrofluorometric determination of hesperidin by manual and flow-injection methods 总被引:1,自引:0,他引:1
T. Pérez-Ruíz C. Martínez-Lozano V. Tomás J. Fenoll 《Fresenius' Journal of Analytical Chemistry》1999,364(3):279-283
A reliable and highly sensitive method for the determination of hesperidin is described. It involves the formation of a highly
fluorescent complex between hesperidin and aluminium (III) in a micellar medium. There is a linear relationship between fluorescence
intensity (λem = 496 nm, λex = 391 nm) and hesperidin concentration over the range 5 × 10–7– 2 × 10–5 mol L–1. The detection limit is 79 μg L–1. The method can easily be adapted to a flow system using a three-channel manifold, the peak height being proportional to
the hesperidin concentration over the range 1 × 10–6– 1 × 10–4 mol L–1. Manual and flow-injection procedures have been successfully applied to the determination of hesperidin in orange peel and
orange juice.
Received: 21 October 1998 / Revised: 16 December 1998 / Accepted: 25 December 1998 相似文献
13.
A. Ruiz-Medina M. L. Fernández-de Córdova A. Molina-Díaz 《Fresenius' Journal of Analytical Chemistry》1999,363(3):265-269
A flow-through optosensor has been prepared for the sensitive and selective determination of pyridoxine (vitamin B6) in aqueous solutions. The sensor was developed in conjunction with a monochannel flow-injection analysis system with fluorimetric
detection using Sephadex SP-C25 resin as an active sorbent substrate. This method of determination is carried out without
any derivatization. The wavelengths of excitation and emission were 295 and 385 nm, respectively. When a HCl (10–3 mol L–1) / NaCl (3 × 10–2 mol L–1) solution is used as carrier solution, the sensor responds linearly in the measuring range of 5–200, 10–400 and 50–1800 ng
mL–1 with detection limits of 0.33, 0.67, and 5.70 ng mL–1 for 2000, 1000 and 200 μL of sample volume, respectively. The relative standard deviation for ten independent determinations
is less than 0.75% for 0.2 and 1.0 mL of sample volumes used, and 1.31% for 2.0 mL of sample volume used. The method was satisfactorily
applied to the determination of vitamin B6 in pharmaceutical preparations.
Received: 4 June 1998 / Revised: 16 July 1998 / Accepted: 6 August 1998 相似文献
14.
Y. Jiang N. Lu Feng Yu Qing Li Hongding Xu 《Analytical and bioanalytical chemistry》1999,364(8):786-787
A method for sampling and determination of hydrogen cyanide in cigarette smoke is described. Cigarette smoke is filtered
through a glass fiber filter paper, and only gaseous compounds, such as hydrogen cyanide, are collected in a dilute sodium
hydroxide solution. The cyanide is determined spectrophotometrically at 550 nm by the isonicotinic acid–pyrazolone method.
Maximum absorbance is achieved within 10 min at room temperature, and remains constant for about 20 min. Beer’s law is obeyed
in the range 0.04∼0.80 μg mL–1 cyanide, with a molar absorptivity of 3.48 × 104 L mol–1 cm–1.
Received: 30 November 1998 / Revised: 21 April 1999 / Accepted: 30 April 1999 相似文献
15.
Y. Jiang N. Lu Feng Yu Qing Li Hongding Xu 《Fresenius' Journal of Analytical Chemistry》1999,364(8):786-787
A method for sampling and determination of hydrogen cyanide in cigarette smoke is described. Cigarette smoke is filtered
through a glass fiber filter paper, and only gaseous compounds, such as hydrogen cyanide, are collected in a dilute sodium
hydroxide solution. The cyanide is determined spectrophotometrically at 550 nm by the isonicotinic acid–pyrazolone method.
Maximum absorbance is achieved within 10 min at room temperature, and remains constant for about 20 min. Beer’s law is obeyed
in the range 0.04∼0.80 μg mL–1 cyanide, with a molar absorptivity of 3.48 × 104 L mol–1 cm–1.
Received: 30 November 1998 / Revised: 21 April 1999 / Accepted: 30 April 1999 相似文献
16.
Manuel H. Blanco María del Carmen Quintana L. Hernández 《Fresenius' Journal of Analytical Chemistry》1999,364(3):254-260
Analytical methods for determining both dihydrozeatin (DHZ) and dihydrozeatin riboside (DHZR) are optimized via voltammetric
anodic stripping using a carbon fiber microelectrode, working in 0.05 M AcH/Ac– buffer pH 4.0, previously accumulated at 0.00 V (vs. Ag/AgCl/ KCl 3 M) for 400 s, at a scan rate of 800 mV · s–1. A detection limit of 40.0 ng · mL–1 and a determination limit of 46.0 ng · mL–1 for the DHZ are obtained. Using the same supporting electrolyte and accumulation potential conditions, but for periods of
70 s and carrying out a stripping scan rate of 900 mV s–1, the detection limit calculated for the DHZR was 14.0 ng · mL–1 and the determination limit obtained was 153 ng · mL–1. The proposed methods were successfully applied to determine minute amounts of cytokinins in apples during their growth period.
Received: 22 July 1998 / Revised: 9 December 1998 / Accepted: 14 December 1998 相似文献
17.
A novel molecularly imprinted polymer solid-phase extraction (MISPE) with flow-injection chemiluminescence (CL) was developed
for the determination of pazufloxacin mesilate (PZFX). The molecularly imprinted polymer (MIP) was synthesized by using PZFX
as the imprinting molecule. A glass tube packed the particles of the MIP was employed as MISPE micro-column, which was connected
into the sampling loop of the eight-way injection valve for on-line selective preconcentration and extraction of PZFX. The
eluent of acetonitrile:acetic acid (9:1, v:v) was used as carrier for eluting the adsorbed PZFX to react with the mixture
of cerium(IV) and sodium sulfite in the flow cell to produce strong CL. The relative intensity of CL was linear to PZFX concentration
in the range from 2.5 × 10−9 to 2.5 × 10−7 g mL−1. The limit of detection was 7 × 10−10 g mL−1 (3 σ) and the relative standard deviation for 5 × 10−8 g mL−1of PZFX solution was 3.7% (n = 7). This method has been applied to the determination of PZFX in human urine. 相似文献
18.
A simple reversed-phase high-performance liquid chromatographic (HPLC) method has been developed for the simultaneous determination
of the antiepileptic drugs (AEDs) zonisamide (ZNS), primidone (PRI), lamotrigine (LTG), phenobarbital (PB), phenytoin (PHT),
oxcarbazepine (OXC), and carbamazepine (CBZ) and two of their active metabolites, monohydroxycarbamazepine (MHD) and carbamazepine
10,11-epoxide (CBZE) in human plasma. Plasma (100 μL) was pretreated by deproteinization with 300 μL methanol containing 20 μg mL−1 propranolol hydrochloride as internal standard. HPLC was performed on a C8 column (4.6 mm × 250 mm; particle size 5 μm) with methanol–acetonitrile–0.1% trifluoroacetic acid, 235:120:645 (v/v), as mobile phase at a flow rate of 1.5 mL min−1. ZNS, OXC, and CBZ were monitored by UV detection at 235 nm, and PRI, LTG, MHD, PB, PHT, and CBZE by UV detection at 215 nm.
Relationships between response and concentration were linear over the concentration ranges 1–80 μg mL−1 for ZNS, 5–50 μg mL−1 for PRI, 1–25 μg mL−1 for LTG, 1–50 μg mL−1 for MHD, 5–100 μg mL−1 for PB, 1–10 μg mL−1 for CBZE, 0.5–25 μg mL−1 for OXC, 1–50 μg mL−1 for PHT, and 1–25 μg mL−1 for CBZ. Intra-day and inter-day reproducibility were adequate (coefficients of variation were ≤11.6%) and absolute recovery
ranged from 95.2 ± 6.13 to 107.7 ± 7.76% for all the analytes; for the IS recovery was 98.69 ± 1.12%. The method was proved
to be accurate, reproducible, convenient, and suitable for therapeutic monitoring of the nine analytes. 相似文献
19.
The electrochemical behavior of the ofloxacin–copper complex, Cu(II)L2, at a mercury electrode, and the interaction of DNA with the complex have been investigated. The experiments indicate that
the electrode reaction of Cu(II)L2 is an irreversible surface electrochemical reaction and that the reactant is of adsorbed character. In the presence of DNA,
the formation of the electrochemically non-active complexes Cu(II)L2-DNA, results in the decrease of the peak current of Cu(II)L2. Based on the electrochemical behavior of the Cu(II)L2 with DNA, binding by electrostatic interaction is suggested and a new method for determining nucleic acid is proposed. Under
the optimum conditions, the decrease of the peak current is in proportional to the concentration of nucleic acids in the range
from 3 × 10−8 to 3 × 10−6 g · mL−1 for calf thymus DNA, from 1.6 × 10−8 to 9.0 × 10−7 g · mL−1 for fish sperm DNA, and from 3.3 × 10−8 to 5.5 × 10−7 g · mL−1 for yeast RNA. The detection limits are 3.3 × 10−9, 6.7 × 10−9 and 8.0 × 10−9 g · mL−1, respectively. The method exhibits good recovery and high sensitivity in synthetic samples and in real samples. 相似文献
20.
A simple flow injection chemiluminescence (CL) method was developed for the determination of atenolol using Eu3+ as the probe. It was found that the weak CL generated by the KMnO4-Na2SO3 reaction can be significantly enhanced by the atenolol-Eu3+ complex. The experimental conditions were optimized. The CL intensity was linearly related to atenolol concentration in the
range from 8.0 × 10−9 to 1.0 × 10−5 g mL−1. The detection limit (3s
b) was 3 × 10−9 g mL−1 and the relative standard deviation for 1.0 × 10−7 g mL−1 atenolol solution was 2.4% (n = 11). The method has high sensitivity, wide linear range, inexpensive instrumentation, and has been applied to the determination
of atenolol in spiked human urine and plasma samples with recoveries within the range 95.5–104.0%.
Supplementary material to this paper is available in electronic form at
Electronic supplementary material: Discussion of the reaction mechanism and additional figures are available online as electronic
supplementary material (ESM) at .
Correspondence: Jianxiu Du, Key Laboratory of Analytical Chemistry for Life Science of Shaanxi Province, School of Chemistry
and Materials Science, Shaanxi Normal University, Xi’an 710062, P.R. China 相似文献