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Analytical & Bioanalytical Electrochemistry - Volume:7 Issue: 5, Oct 2015

Analytical & Bioanalytical Electrochemistry
Volume:7 Issue: 5, Oct 2015

  • تاریخ انتشار: 1394/09/10
  • تعداد عناوین: 10
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  • Magadi Puttaswamy Deepak, Ganjeenahalli Puttagiddappa Mamatha* Pages 523-538
    The tin oxide (SnO2) nanoparticles were synthesized by the gel combustion method. The synthesized SnO2 nanoparticles & L-tyrosine were used for the modification of carbon paste electrode. The voltammetric behavior of ciprofloxacin hydrochloride (CIP) on the poly(L-tyrosine)/SnO2 nanoparticles modified carbon paste electrode was investigated by using cyclic voltammetry (CV) and differential pulse voltammetry (DPV). The proposed sensor was successfully applied for the determination of CIP in real samples such as CIP in ciprodac tablets. The practical application of the modified electrode in the determination of CIP has good selectivity and high sensitivity.
    Keywords: Ciprofloxacin hydrochloride, Modified carbon paste electrode, Cyclic voltammetry
  • Jayant I. Gowda, Sharanappa T. Nandibewoor* Pages 539-554
    A sensitive determination of paclitaxel (PAC) at physiological pH was developed by carbon paste electrode using cyclic, linear sweep and differential pulse voltammetric techniques. The voltammetric response of paclitaxel was excellent with carbon paste electrode at sweep rate of 50 mV/s in the potential range from 0.8 V to 1.4 V. The voltammogram of paclitaxel was irreversible. The effect of scan rate showed that the electrode process was diffusion controlled. The concentration and pH effects on the voltammogram of paclitaxel were studied. Under optimized conditions, the concentration range and detection limit were 2.0×10−6 to 2.0×10−5 M and 4.6×10−9 M, respectively. The analytical performance of this electrode was evaluated for the detection of paclitaxel in pharmaceutical and real samples.
    Keywords: Voltammetry, Paclitaxel, Carbon paste electrode, Pharmaceutical dosage, Human biological fluids
  • Manimangalam Lavanya, Yenugu Veera Manohara Reddy, Sundupalle Kiranmai, Manthrapudi Venu, Gajulapalle Madhavi* Pages 555-568
    In this, we have studied the preparation, characterization and application of a poly Safranin Triton X-100 (SFRTX-100) modified carbon paste electrode for the simultaneous determination of dopamine (DA) in presence of ascorbic acid (AA) without any interference in 0.1 M phosphate buffer solution (PBS) with a scan rate of 50 mV/s by using cyclic and differential pulse voltammetry techniques. Modified electrode was successfully applied for the determination of DA in pharmaceutical and human serum samples with good results. Bare carbon paste electrode (BCPE) and modified carbon paste electrode (MCPE) was characterized by scanned micrographs. Modified electrode exhibited a well-defined redox peak of dopamine (DA) due to electrostatic interaction of poly(SFRTX-100) monolayer. Limit of detection (LOD) and quantification (LOQ) of DA was found to be 1.78×10-7 M and 5.43×10-6 M respectively. The poly(SFRTX-100) showed excellent sensitivity, selectivity and stability which are more favorable for the detection of DA in physiological matrices.
    Keywords: Dopamine, Ascorbic acid, Safranin, Triton X, 100, Cyclic voltammetry, Differential pulse voltammetry
  • Ali A. Ensafi*, Alireza Allafchian, Behzad Rezaei Pages 569-581
    A new coated–wire membrane selective electrode as a potentiometric sensor was developed for the determination of isoproterenol. Naphthylethylenediamine dihydrochloride–tetraphenyl boranuide ion–exchangers was used as an electroactive material on the membrane. The sensor displays a linear response with a slope of 56.9 mV decade–1 for isoproterenol in the concentration range of 1.0×10–2–5.0×10–6 mol L–1, with detection limit of 3.3×10–6 mol L–1. The potentiometric response is independent of the pH of the solution in the pH range of 3.0 – 6.8. Selectivity coefficient data for some common inorganic cations, sugars and components of the mixed drugs were investigated and showed negligible interference. The response time of <5 s was displayed. The sensor can be used for more than 2 months without any considerable divergence in the potential. For the practical purposes, the efficiency of the method in the extraction and determination of isoproterenol for biological fluids such as urine and blood serum samples was evaluated without any special pretreatment.
    Keywords: Isoproterenol, Potentiometry, Coated wire electrode, Potentiometric titration
  • Jahan Bakhsh Raoof*, Mohammad Ali Karimi, Leila Asadian, Zarrinabadi, Mohaddeseh Amiri, Aref Pages 582-594
    The utilization of acetaminophen (AC) as a homogeneous electrocatalyst in the presence of N-acetyl-L-cysteine (NAC) at the surface of carbon paste electrode (CPE) modified with multi-walled carbon nanotubes (MWCNT) has been surveyed in aqueous medium using double step potential chronoamperometry (CHA), cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. Though, NAC itself shows a very negligible electrochemical response at bare CPE, the response could be greatly increased in the presence of acetaminophen at MWCNT paste electrode (MWCNT-CPE) which enables a sensitive electrochemical determination of the NAC. The kinetic parameters such as transfer coefficient (α), the apparent diffusion coefficient (Dapp) and the chemical reaction rate constant (kh) were calculated 0.33, 5.56×10-6 cm2 s-1 and 1.35×102 cm3 mol-1 s-1, respectively. A linear calibration range of 1.0×10-6 M-3.0×10-5 M and detection limit of 3.9×10-7 M were obtained for determination of NAC at MWCNT-CPE using DPV. The offered method is useful for the routine analysis of NAC in real sample.
    Keywords: N, acetyl, L, cysteine, Acetaminophen, Multi, Walled Carbon Nanotubes, Homogeneous electrocatalyst
  • Patri Jeevan Jyoti, Yenugu Veera Manohara Reddy, Kalluru Gangadhara Reddy, Manimangalam Lavanya, Gajulapalle Madhavi* Pages 595-609
    A voltammetric electro chemical sensor was developed for the resolution study of dopamine and ascorbic acid by the electrochemically deposited succinic acid polymer on a carbon paste electrode at 50 mVs−1/Ag–AgCl. This modified electrode exhibited an excellent electrochemical catalytic activity towards the resolution of ascorbic acid (AA), dopamine (DA) and uric acid (UA) compared with bare carbon paste electrode. The effect of pH range from 5.5 to 8.0 was studied and the redox peak was pH dependent with a slope of 60 mV/pH and from the regression coefficient of the effect scan rate was shows the process is diffusion controlled. The DPV study of 57 to 438 μM concentration range of DA shows 34 μM detection limit. The oxidation potentials of AA, DA and UA at the poly succinic acid modified carbon paste electrode were shifted slightly negatively and the peak currents were much larger than the bare carbon paste electrode. The limit of detection for AA, DA and UA were 0.7 mM, 1.0 μM and 79 μM respectively. This succinic acid modified carbon paste electrode showed many merits in constancy, sensitivity, capability, economy and also applicable for real sample analysis.
    Keywords: Succinic acid, Ascorbic acid, Uric acid, Dopamine, Cyclic voltammetry, Differential pulse voltammetry
  • Mohan Kumar, Bahaddurghatta E. Kumara Swamy*, Tammanekar V. Sathisha, Ramachandra Deepa Pages 610-622
    Zinc oxide (ZnO) modified carbon paste electrode (MCPE) was used for the electrochemical studies of potassium ferrocyanide (K4[Fe(CN)6]) and uric acid (UA). The effect of amount of ZnO in carbon paste electrode (CPE), scan rate and concentration studies of K4[Fe(CN)6] and UA were carried out. The electrochemical sensitivity of CPE/Triton X-100(TX-100), CPE/ZnO/TX-100, CPE/cetyltrimethyl ammonium bromide (CTAB), CPE/ZnO/CTAB, CPE/Polyglycine (PG) and CPE/ZnO/PG were studied towards uric acid.
    Keywords: Zinc oxide, Polyglycine, Uric acid, Modified Carbon paste electrode, Cyclic voltammogram
  • Sayed Zia Mohammadi*, Hadi Beitollahi, Sareh Moharrer, Ali Akbari Pages 623-634
    A carbon paste electrode (CPE) modified with 3-(4'-amino-3'-hydroxy-biphenyl-4-yl)-acrylic acid and multi-walled carbon nanotubes (MWCNTs), was prepared for simultaneous determination of ascorbic acid (AA) and acetaminophen (AC). The electrochemical response characteristics of the modified electrode toward AA and AC were investigated by cyclic voltammetry and square wave voltammetry (CV and SVW). The results showed an efficient catalytic role for the electro-oxidation of AA and AC, leading to a remarkable peak resolution (~320 mV) for two compounds. The mechanism of the modified electrode was analyzed by monitoring the CVs at various potential sweep rates and pHs of the buffer solutions. Under the optimum conditions, the calibration curve for AA was obtained in the range of 1.0×10-8-4.0×10-5 M. The proposed method was applied to determination of AA and AC in commercial drugs and in urine samples and the obtained results were satisfactory.
    Keywords: Ascorbic acid, Acetaminophen, Simultaneous determination, Carbon nanotube paste electrode
  • Mohammad Reza Ganjali*, Bagher Larijani Pages 635-646
    Citalopram (CP), which is a selective serotonin reuptake inhibitor (SSRI), is used for the treatment depression. Due to the importance of the analysis of this compound, an all-solid-state polymeric membrane electrode (ASS-PME) has been devised using an ion-pair agent as the sensing element of the device. The experimental results proved that the best sensor response is observed using membranes including 7%wt CP-tetraphenyl borate (the sensing element), 57%wt dibutyl phthalate as the solvent mediator, 33%wt poly(vinyl chloride) and 3%wt of an ionic liquid. The ASS element of the device is a conductive composite of graphite, multiwall carbon nanotubes (MWCNTs), and epoxy resin which is coated on a Cu wire, which is finally coated with a thin film of the PME. The response of the ASS-PME was linear in the range of 1.0×10-7 to 1.0×10-3 mol L-1 and reached the slope of 57.3±0.3 mV/decade under optimal conditions. The experiments revealed that the optimized Citalopram ASS-PME is applicable in the quality control analyses, which was validated by its application for measurement of Citalopram in its tablets.
    Keywords: Citalopram, Sensor, All solid state, Potentiometry, Pharmaceutical formulation
  • Rekha, Bahaddurghatta Eshwaraswamy Kumara Swamy*, Pattan Siddappa Ganesh Pages 647-656
    The multi-walled carbon nanotube modified carbon paste electrode (MWCNTMCPE) was used for the voltammetric investigation of folic acid (FA) and uric acid (UA) in physiological pH of 7.4. The scan rate and concentration study reveals that the electrode process was controlled by diffusion of the analytes. The sensitive separation for the binary mixture of FA and UA was observed by cyclic voltammetric and differential pulse voltammetric techniques. A simple modification procedure was reported for the determination of FA and UA.
    Keywords: Folic acid, Uric acid, Multi, walled Carbon Nanotube, Voltammetry