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1.
Newly developed, simple, low-cost and sensitive ion-selective electrodes have been proposed for determination of some antiepileptic
drugs such as lamotrigine, felbamate, and primidone in their pharmaceutical preparations as well as in biological fluids.
The electrodes are based on poly(vinyl chloride) membranes doped with drug–tetraphenyl borate (TPB) or drug–phosphotungstic
acid (PT) ion-pair complexes as molecular recognition materials. The novel electrodes displayed rapid Nernstian responses
with detection limits of approximately 10−7 M. Calibration graphs were linear over the ranges 5.2 × 10−7–1.0 × 10−3, 1.5 × 10−6–1.0 × 10−3, and 2.6 × 10−7–1.0 × 10−3 M for drug–TPB and 5.8 × 10−7–1.0 × 10−3, 1.8 × 10−7–1.0 × 10−3, and 6.6 × 10−7–1.0 × 10−3 M for drug–PT electrodes, respectively, with slopes ranging from 52.3 to 62.3 mV/decade. The membranes developed have potential
stability for up to 1 month and proved to be highly selective for the drugs investigated over other ions and excipients. The
results show that the selectivity of the ion-selective electrodes is influenced significantly by the plasticizer. The proposed
electrodes were successfully applied in the determination of these drugs in pharmaceutical preparations in four batches of
different expiry dates. Statistical Student’s t test and F test showed insignificant systematic error between the ion-selective electrode methods developed and a standard method. Comparison
of the results obtained using the proposed electrodes with those found using a reference method showed that the ion-selective
electrode technique is sensitive, reliable, and can be used with very good accuracy and high percentage recovery without pretreatment
procedures of the samples to minimize interfering matrix effects.
Figure Structure of lamotrigine, felbanate and primidone 相似文献
2.
A novel lidocaine ion-selective electrode is prepared, characterized and used in pharmaceutical analysis. The electrode incorporates
PVC-membrane with lidocaine-sulfathiazole ion pair complex. The influences of membrane composition, temperature, pH of the
test solution, and foreign ions on the electrode performance were investigated. The electrode showed a Nernstian response
over a lidocaine concentration range from 1.0 ×10−5 to 1.0 × 10−1 mol L−1 with a slope of 60.1 ± 0.2 mV per decade at 25°C and was found to be very selective, precise, and usable within the pH range
5–9.5. The standard electrode potentials, E
o, were determined at 10, 15, 20, 25, 30, 35 and 40°C, and used to calculate the isothermal temperature coefficient (dE
o/dT=−0.0003 V °C−1) of the electrode. However, the electrode performance is significantly decreased at temperatures higher than 45°C. The electrode
was successfully used for potentiometric determination of lidocaine hydrochloride in pharmaceutical products.
The article is published in the original. 相似文献
3.
Magda M. Ayad Abdalla Shalaby Hisham E. Abdellatef Heba M. Elsaid 《Mikrochimica acta》2002,140(1-2):93-96
The construction of a plasticised PVC matrix-type promazinium cation-selective membrane electrode and its use in the potentiometric
determination of promazine hydrochloride in pharmaceutical preparations are described. It is based on the use of the ion-associate
species, formed by promazinium cation and tetraphenylborate (TPB) counter ion. The basic electrode performance characteristics
are evaluated according to IUPAC recommendations. It exhibited a linear response for 1 × 10−2−1 × 10−5 M of promazine hydrochloride solutions with a cationic Nernstian slope over the pH range 2–6. Common organic and inorganic
cations showed negligible interference. Direct potentiometric determination of 1 × 10−2−1 × 10−5 M aqueous promazine hydrochloride using this membrane electrode system showed an average recovery of 99.5% with a mean standard
deviation of 1.5%. This electrode was successfully used for monitoring the titration of promazine hydrochloride with sodium
tetraphenyl borate and for determining promazine hydrochloride in ampoules.
Received June 15, 2001 Revision November 6, 2001 相似文献
4.
Won-Sik Han Young-Hoon Lee Soon-Nyeo Lee Tae-Kee Hong 《Journal of Analytical Chemistry》2011,66(9):854-858
Iodide ion selective poly(aniline) solid contact electrode based on quinine-Cu ionophore as a sensing material has been successfully
developed. The electrode exhibits good linear response of 52.0 mV/decade (at 20 ± 0.2°C, r
2 = 0.9998) within the concentration range of 1 × 10−6.4–1 × 10−1.0 M KI. The composition of this electrode was quinine-Cu 2.0: PVC 30.0: bis(2-ethylhexyl)sebacate 68.0 (mass). This plasticizer
provides the best response characteristics. The electrode shows good selectivity for iodide ion in comparison with any other
anions and is suitable for use with aqueous solutions of pH 3.3–9.4. The standard deviations of the measured EMF difference
were ±1.4 and ±1.3 mV for iodide sample solutions of 1.0 × 10−2 M and 1.0 × 10−3 M, respectively. The stabilization time was less than 10 min and response time was less than 15 sec. 相似文献
5.
M. Mazloum Ardakani P. Ebrahimi M. R. Mansournia 《Russian Journal of Electrochemistry》2008,44(9):1065-1072
A new salicylate-selective electrode based on the complex (2,3;6,7;10,11;14,15-tetraphenyl-4,9,13,16-tetraoxo-1,5,8,12-tetraazacyclohexadecane)
copper(II) [CuL] as the membrane carrier was developed. The electrode exhibits a good Nernstian slope of −60.9 ± 1.0 mV/decade
and a linear range from 1.0 × 10−6 to 1.0 × 10−1 M for salicylate. The detection limit is 5.0 × 10−7 M. The electrode has a fast response time (5–15 s) and can be used for more than three months. The selective coefficients
were determined by the fixed interference method (FIM) and separate solution method (SSM). The salicylate-selective electrode
could be used in the pH range 3.5–10.5. It was employed as an indicator electrode for direct determination of salicylate in
pharmaceutical samples.
Published in Russian in Elektrokhimiya, 2008, Vol. 44, No. 9, pp. 1147–1154.
The text was submitted by the authors in English. 相似文献
6.
《Fresenius' Journal of Analytical Chemistry》1992,344(1-2):34-38
Summary The anodic voltammetric behaviour of pentachlorophenol at a silica gel-modified carbon paste electrode in aqueous solution
is reported. Adsorption of the fungicide onto the electrode under open-circuit conditions is followed by application of either
differential or square wave voltammetry. The results obtained by differential pulse voltammetry at pH 2.9, with a modifier
concentration of 10% and accumulation times of 120 and 300 s, allowed the development of a method to determine pentachlorophenol
in the ranges of 1.0×10−6–1.0×10−5 and 1.0×10−7–1.0×10−6 mol l−1. The relative standard deviation is 2.6% for a concentration of 2.0×10−7 mol l−1, with a detection limit of 1.8×10−8 mol l−1 (5 ppb). The effect of other chlorophenols was studied. The results obtained by square wave voltammetry showed a behaviour
typical of an irreversible electron transfer. Amplitude, step height and frequency were optimised, taking into account the
resolution of the voltammetric response. No improvement in sensitivity was obtained with respect to DPV. Good results were
obtained by applying the proposed differential-pulse voltammetric method to the determination of pentachlorophenol in a commercial
fungicide. 相似文献
7.
Won-Sik Han Jang-Ki Kim Koo-Chun Chung Joo-Yeon Hong Jong-Ki Hong Jeong-Hoon Kim Tae-Kee Hong 《Journal of Analytical Chemistry》2010,65(10):1035-1040
Udenafil is an oral agent for treating male erectile dysfunction. The poly(aniline) solid contact selective electrodes for
udenafil have been fabricated from PVC cocktail solutions with three ion selective ion pairs. This solid contact electrode
contains three layers of Pt/electro-conductive poly(aniline) polymer/PVC film with an ionophore with a thickness of 2.5 ±
0.1 mm. We compared the slopes of EMF responses and the response range of a solid contact electrode based on Udenafil-TmCIPB
ion pair with those based on Udenafil-PMA and Udenafil-TPB ion pairs and showed that the response slopes were influenced by
plasticizers. The EMF response slopes of Udenafil-TmCIPB-based solid contact electrodes equalled 58.0 mV/decade (at 20 ± 0.2°C)
and their linear response dynamic ranges were 1.0 × 10−2∼1.0 × 10−5.85 M (r
2 = 0.9984). When electrodes with 6 different plasticizers based on Udenafil-TmCIPB were compared, as the dielectric constant
of PVC plasticizer increased, so was the response slope at the same time. Having applied the electrodes to artificial serum
directly, we could get same satisfactory results [Nernstian slope: 60.3 mV/decade, dynamic range: 1.0 × 10−2∼1.0 × 10−5.78 M (r
2 = 0.9978) in artificial serum]. Solid contact electrodes with Udenafil-TmCIPB have shown the best selectivity, reproducibility
of EMF, long-term stability, and short response time (< 20 s). 相似文献
8.
Maha El-Tohamy Sawsan Razeq Magda El-Maamly Abdalla Shalaby 《Central European Journal of Chemistry》2010,8(4):937-945
The construction and performance characteristics of phenytoin sodium selective electrodes are detailed. Two types of electrodes:
plastic membrane I and coated wire II, were constructed based on the incorporation of phenytoin sodium with tungstosilicic
acid. The influence of membrane composition, kind of plasticizer, pH of the test solution, soaking time and the electrodes’
foreign ions were investigated. The electrodes showed a Nernstian response with a mean calibration graph slope of 30.9±0.1
and 28.9±0.1 mV decade−1 at 25°C for electrode I and II respectively, over a phenytoin sodium concentration range of 5×10−3−5×10−6 M and 1×10−3−1×10−6 M with a detection limit 1.3×10−6 M and 2.5×10−7 M for electrode I and II, respectively. The electrodes gave average selective precision and were usable within the pH range
6–10. Interference studies from common cations, alkaloids, sugars, amino acids and drug excipients are reported. The results
obtained by the proposed electrodes were also applied successfully for the determination of the drug in pharmaceutical preparations
and biological fluids. 相似文献
9.
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
10.
The fabrication and electrochemical characteristics of a penicillamine (PCA) self-assembled monolayer modified gold electrode
were investigated. The electrode can enhance the electrochemical response of uric acid (UA), and the electrochemical reaction
of UA on the PCA electrode has been studied by cyclic voltammetry and differential pulse voltammetry. Some electrochemical
parameters, such as diffusion coefficient, standard rate constant, electron transfer coefficient and proton transfer number
have been determined for the electrochemical behavior on the PCA self-assembled monolayer electrode. The electrode reaction
of UA is an irreversible process, which is controlled by the diffusion of UA with two electrons and two protons transfer at
the PCA/Au electrode. In phosphate buffer (pH 5.0), the peak current is proportional to the concentration of UA in the range
of 6.0 × 10−5–7.0 × 10−4 mol L−1 and 2.0 × 10−5–7.0 × 10−4 mol L−1 for the cyclic voltammetry and differential pulse voltammetry methods with the detection limits of 5.0 × 10−6 and 3.0 × 10−6 mol L−1, respectively. The method can be applied to determine UA concentration in real samples. 相似文献
11.
Multiwalled carbon nanotubes-polymeric alizarin film modified electrode was made. The electrochemical behavior of levofloxacin
hydrochloride on modified electrode was studied with cyclic voltammetry, linear sweep voltammetry and chronopotentiometry.
The results indicated that the electrical oxidation of levofloxacin hydrochloride on MWNT-PAR electrode, in HAc-NaAc buffer
solution at pH 4.2 was irreversible and was controlled by diffusion. Some important parameters m, n, D, E
D, ΔS
rc and ΔH
rc of the electrochemical process were evaluated. Good linearity relationship between peak current and its concentration in
the range of 5.0 × 10−6–1.0 × 10−4 mol l−1 was found, of which the equation was I
p(A) = −5.456 × 10−6 0.2667c, the correlative coefficient r = −0.9976 and detect limitation was 4.0 × 10−7 mol l−1. The recovery of levofloxacin hydrochloride in levofloxacin hydrochloride injection was between 94.6 and 104.7%. 相似文献
12.
M. R. Ganjali P. Norouzi R. Dinarvand F. Faribod A. Moghimi 《Journal of Analytical Chemistry》2008,63(7):684-689
In this work, for the first time, we introduce a highly selective and sensitive Be(II) microsensor. 4-nitrobenzo-9-crown-3-ether
(NBCE) was used as a membrane-active component to prepare a Be(II)-selective polymeric membrane microelectrode. The electrode
exhibits a Nernstian response toward Be(II) ions over a very wide concentration range (1.0 × 10−4–1.0 × 10−10 M), with a detection limit of 3.5 × 10−11 M (∼350 pg/L). In fact, the electrode presents a fast response time in the whole concentration range (6 s). The proposed
microelectrode can be used for at least six weeks without any considerable divergence in the potentials. The proposed membrane
sensor revealed a selectivity toward Be(II) ions over a wide variety of other metal ions including common alkali, alkaline-earth,
and rare-earth ions. It could be used in the pH range of 3.0–11.5. The microelectrode was successfully used as an indicator
electrode for the titration of 20 mL of 1.0 × 10−6 M Be2+ solution with 1.0 × 10−4 M of EDTA. It was also applied to the direct determination of beryllium ions in beryl and binary mixtures.
The text was submitted by the authors in English. 相似文献
13.
Dong Mei Gao Yuan Yuan Sun Qiongyan Zhao Jing Bo Hu Qi Long Li 《Mikrochimica acta》2008,160(1-2):241-246
A novel electrode was prepared by implanting NH2
+ into an ITO film (NH2/ITO). Gold nanoparticles were deposited on the surface of NH2/ITO electrode. The NH2/ITO and Au/NH2/ITO electrodes were used to determine hemoglobin (Hb) immobilized on the electrodes surfaces. The relationship of the reductive
peak current value of Hb among different electrodes was: Hb/ITO:Hb/Au/ITO:Hb/NH2/ITO:Hb/Au/NH2/ITO=1:1.5:2:4. The linkage between the –NH2 implanted into ITO film and the –COOH of Hb was recognized to be the reason for the increase of active Hb coverage on NH2/ITO electrode compared with the ITO electrode. Increase of active Hb coverage on Au/NH2/ITO compared with Au/ITO was attributed to the different amount of gold nanoparticles deposited. The determination of Hb
at an Au/NH2/ITO electrode was optimized. Calibration curve was obtained over the range of 1.0 × 10−8 – 1.0 × 10−6 mol · L−1 with a detection limit of 1.0 × 10−8 mol · L−1. Results showed that the novel NH2/ITO and Au/NH2/ITO electrodes exhibited good stability, reproducibility besides better electrochemical performance.
Correspondence: Jing Bo Hu, Department of Chemistry, Beijing Normal University, Beijing 100875, China 相似文献
14.
Jun Yue Bai Liang Wang Hong Jing Wang Peng Fei Huang Yu Qing Zhao Sheng Di Fan 《Mikrochimica acta》2006,156(3-4):321-326
The electrochemical behavior of epinephrine (EP) at a mercaptoacetic acid (MAA) self-assembled monolayer modified gold electrode
was studied. The MAA/Au electrode is demonstrated to promote the electrochemical response of epinephrine by cyclic voltammetry.
The possible reaction mechanism is also discussed. The diffusion coefficient D of EP is 6.85 × 10−6 cm2 s−1. In 0.1 mol L−1 phosphate buffer (pH 7.20), a sensitive oxidation peak was observed at 0.177 V, and the peak current is proportional to the
concentration of EP in the range of 1.0 × 10−5–2.0 × 10−4 mol L−1 and 1.0 × 10−7–1.0 × 10−6 mol L−1. The detection limit is 5 × 10−8 mol L−1. The modified electrode is highly stable and can be applied to the determination of EP in practical injection samples. The
method is simple, quick, sensitive and accurate. 相似文献
15.
Reza Ansari Ali Fallah Delavar Alireza Aliakbar Ali Mohammad-khah 《Journal of Solid State Electrochemistry》2012,16(3):869-875
A pencil graphite electrode coated by copper (II)–carmoisine dye complex in polyaniline (emeraldine base form) matrix (termed
as PGE/PA/Cu-Car) was prepared and used as copper ion-selective electrode. The introduced electrode was found to have high
selectivity toward copper ion (II) and exhibited wide working concentration range, low response time, and good shelf life.
The sensor electrode showed a linear Nernstian response over the range of 5.0 × 10−6 to 1.0 × 10−1 M with a slope of 29.7 ± 1 mV per decade change in concentration. A detection limit of 2.0 × 10−6 M was obtained. The optimum pH working range of the electrode was found to be 4.0–7.0. 相似文献
16.
A Pt wire coated with a bentonite–carbon composite in a poly(vinyl chloride) membrane was used for detection of lead. The
sensor has a Nernstian slope of 29.42±0.50 mV per decade over a wide range of concentration, 1.0×10−7 to 1.0×10−3 mol L−1 Pb(NO3)2. The detection limit is 5.0×10−8 mol L−1 Pb(NO3)2 and the electrode is applicable in the pH range 3.0–6.7. It has a response time of approximately 10 s and can be used at
least for three months. The electrode has good selectivity relative to nineteen other metal ions. The practical analytical
utility of the electrode is demonstrated by measurement of Pb(II) in industrial waste and river water samples. 相似文献
17.
Mojtaba Shamsipur Sohrab Ershad Naser Samadi Abloghasem Moghimi Hossein Aghabozorg 《Journal of Solid State Electrochemistry》2005,9(11):788-793
A new modified carbon paste electrode based on a recently synthesized mercury (II) complex of a pyridine containing proton
transfer compound as a suitable carrier for Br− ion is described. The electrode has a linear dynamic range between 3.00×10−2 and 1.0×10−5 M with a near-Nernastian slope of 61.0±0.9 mV per decade and a detection limit of 4.0×10−6 M (0.32 ppm). The potentiometric response is independent of the pH of the solution in the pH range 4.0–8.3. The electrode
possesses the advantages of low resistance, fast response and good over a variety of other anions. It was applied as an indicator
electrode in potentiometric titration of bromide ions and for the recovery of Br− from tap water. 相似文献
18.
Panpan Gai Zhiyong Guo Fei Yang Jing Duan Tingting Hao Sui Wang 《Russian Journal of Electrochemistry》2011,47(8):940-947
In this work, a highly-sensitive polymeric membrane ion selective electrode for determination of tetracycline was constructed
by using molecularly imprinted polymer (MIP) particles as quasi-ionophore. The water-compatible MIP particles targeting tetracycline
were synthesized with tetracycline as a template molecule, methacrylic acid as a functional monomer, ethylene glycol dimethacrylate
as a cross-linker, 2,2′-azobisisobutyronitrile as an initiator and lanthanum ion as a mediator. Benefited from the distinctive
performance of the quasi-ionophore and the optimized composition of the membrane and the inner filling solution, the lower
detection limit of the electrode was decreased to about 1 × 10−8 mol/l. It exhibited a good electrode slope 59.8 mV/decade near the theoretical Nernstian one, with a wide linear working
range from 2.0 × 10−8 to 1.0 × 10−3 mol/l. Due to the specific recognition of tetracycline by the MIP particles, the selectivity coefficients for routine interferences
were less than 10−4. The fabricated electrode should be used in pH 2–4, response time of which was less than 200 s when the concentration of
tetracycline was higher than 1.0 × 10−6 mol/l and no more than 30 min at the concentration of 1.0 × 10−8 mol/l. Finally, the proposed highly-sensitive ion selective electrode has been successfully applied to the determination
of tetracycline in aqueous samples. 相似文献
19.
A new post-chemiluminescence (PCL) phenomenon was observed when phenothiazine medications were injected into the reaction
mixture after the chemiluminescence (CL) reaction of luminol and potassium ferricyanide had finished. A possible reaction
mechanism was proposed based on studies of the kinetic characteristics of the CL, CL spectra, fluorescence spectra, and on
other experiments. The feasibility of determining various phenothiazine medications by utilizing these PCL reactions was examined.
A molecular imprinting–post-chemiluminescence (MI-PCL) method was established for the determination of chlorpromazine hydrochloride
using a chlorpromazine hydrochloride-imprinted polymer (MIP) as the recognition material. The method displayed high selectivity
and high sensitivity. The linear range of the method was 1.0×10−8∼1.0×10−6, with a linear correlation coefficient of 0.9985. The detection limit was 3×10−9 g/ml chlorpromazine hydrochloride, and the relative standard deviation for a 1.0×10−7 g/ml chlorpromazine hydrochloride solution was 4.0% (n=11). The method has been applied to the determination of chlorpromazine hydrochloride in urine and animal drinking water
with satisfactory results.
相似文献
20.
By combining the layer-by-layer (LBL) self-assembly technique with the electrochemical polymerization method, multilayer Ni(II)-polyluminol
films were modified on the surface of a vaseline-impregnated graphite electrode. It was found that, compared with an electrode
modified by direct electrochemical polymerization, this modified electrode offered a suitable ECL reaction micro-environment
created by the special multilayer films, which was beneficial to the ephedrine hydrochloride enhancing effect for luminol
ECL intensity. The ECL enhancing effect of ephedrine hydrochloride on the electro-oxidation luminol was improved on this modified
electrode. Based on this finding, a new sensitive ECL method was developed for ephedrine hydrochloride determination under
the optimal conditions. At the same time, a new idea is proposed for improving the analytical performance of the luminol ECL
system by modifying the ECL reaction micro-environment with the layer-by-layer self- assembly method. Under the optimum experimental
conditions, the ephedrine hydrochloride concentration in the range of 2.0 × 10−8–7.0 × 10−6 mol L−1 was proportional to the enhanced ECL signal, and it offered an 8.0 × 10−9 mol L−1 detection limit for ephedrine hydrochloride. 相似文献