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Nanotube-structured TiO2 electrodes on Ti plates were formed in ethylene glycol solution by the anodic oxidation method applied for different times and calcined at 500 °C. Different amounts of WO3 were decorated on the nanotube surfaces electrochemically. The electrodes were characterized, and the effects of the nanotube length on the Ti plate, decorated WO3 amount, electrolyte concentration, applied potential, and type of radiation source on the oxidation of 3-methylpyridine were investigated, together with the product distribution/selectivity. In a photoelectrocatalytic system, the vitamin B3 yield increased significantly (ca. 17 fold) under UVA by decorating nanotube-structured TiO2 with WO3, whilst low reaction rates and no products were found under Vis irradiation, as only unselective photolytic reactions occurred. This unexpected result was clarified for the first time in the literature.

Mean platelet volume (MPV) has been related to erectile dysfunction (ED). However, its value in predicting therapeutic response to phosphodiesterase-5 inhibitors is not evaluated. This study aimed to investigate the value of MPV as a marker for the prediction of the response of the tadalafil treatment of ED. A retrospective analysis of patients who were admitted to the andrology outpatient clinic between 2020-2022 were performed. The inclusion criteria were, ≥40 years old male, International Index of Erectile Function-Erectile Function domain score 26, not received any ED treatment before, have a stable heterosexual relationship, and prescribed 5 mg daily tadalafil for primary treatment of ED. A total of 116 patients were included in the study. The mean age of the patients was 53.7 ± 8.7 years. The response rate to 5 mg tadalafil treatment was 52.6% (Group-1; N = 61). An MPV value

Carbon paste electrodes (CPE) were modified with commercial (Degussa P25, BDH, Merck, Hombikat) and home-prepared rutile TiO2 (HPRT) nanoparticles for the electrochemical determination of arbutin (AR) by differential pulse voltammetry technique. The optimization experiments were performed in Britton-Robinson buffer at pH 2–7 using modified CPEs. 15%-HPRT(25 °C)/CPE and 15%-HPRT(400 °C)/CPE showed the highest current values among all electrodes at optimum pH, accumulation potential, and duration time values (pH 2, 0.70V and 45 s); consequently, the electrodes were characterized by SEM-EDX, while TiO2 samples by BET and XRD techniques. Electrochemical surface areas of the electrodes were also determined. HPRT(25 °C) and HPRT(400 °C) samples have the lowest crystallinity which is the reason for their high performance. The linear working range of 15%-HPRT(25 °C)/CPE and 15%-HPRT(400 °C)/CPE electrodes was 0.5–120 μM. The detection limit for these electrodes was 32 and 40 nM, and the quantification limit was 107 and 135 nM, respectively. Interference studies, repeatability, reproducibility and the stability of the electrodes were examined, and a reaction mechanism for AR oxidation was proposed and promising results were obtained. The AR determination in a real sample, in the anti-blemish skin serum, was also performed successfully.

The photoelectrocatalytic (PEC) oxidation of 3-pyridinemethanol to 3-pyridinemethanal and vitamin B3 was investigated by using Pt, Au and Pd loaded (as single or bimetallic) nanotube structured TiO2 on Ti plate in water under UVA irradiation. Nanotube structured TiO2 on Ti plate samples were prepared as anode by anodic oxidation method in ethylene glycol solution in different times, and then they were calcined at 500 °C to be obtained in crystalline form. The anodes were loaded with noble metals by electrochemical reduction method and characterized by XRD, XPS, SEM, and photocurrent techniques. The TiO2 on the plates was in the anatase phase. The loaded metals were in metallic form and heterogeneously dispersed on the TiO2 surface in different sizes. The results indicate that a high amount of metal loading negatively affected the PEC activity of the metal loaded samples because UVA irradiation inside the nanotubes was inhibited by the presence of the metal. On the contrary, low amount of Pd showed high PEC activity and high product selectivity values with respect to the pristine sample. PEC experiments were also more selective than the photocatalytic ones for vitamin B3 production. Electrocatalytic (EC) and photocatalytic (PC) experiments were also conducted, however no or low activity was obtained, respectively. PEC experiments showed to be more selective than the PC ones for vitamin B3 production.

Bu calismada, kalem ucu elektrot yuzeyinde elektrokimyasal sentezlenerek asiri yukseltgenen polipirol nanofiber elektrotlar hazirlanmis ve (KUE/AYPP-NF) epinefrin tayinlerinde elektrokimyasal sensor olarak kullanimi arastirilmistir. Modifiye elektrodun epinefrin (adrenalin) tayinlerine yonelik elektrokimyasal incelenmesinde ve analitik performanslarinin belirlenmesinde donusumlu voltametri ve diferansiyel puls voltametri (DPV) teknigi kullanilmistir. Epinefrin tayinlerine pH’nin etkisi fosfat tamponu cozeltisinde KUE/AYPP-NF kullanilarak incelenmis ve en yuksek pik akimina pH 4,0 degerinde ulasildigi tespit edilmistir. Nanofiber yapida olmayan asiri yukseltgenis polipirol ile karsilastirildiginda nanofiber yapinin epinefrin yukseltgenmesini arttirdigi belirlenmistir. DPV teknigi kullanilarak KUE/AYPP-NF icin epinefrin yukseltgenmesine ait pik akimi 10-200 µM arasinda 0,998 korelasyon katsayisi ile dogrusallik gostermektedir . Tayin siniri (LOD) 2,2 µ M olarak hesaplanmistir (S/N=3). Sonuclar KUE/AYPP-NF elektrotlarin epinefrin tayinlerinde elektrokimyasal sensor olarak kullanilabilecegini gostermistir.

Photoelectrocatalytic (PEC) oxidation of glycerol to commercially valuable compounds was carried out using nanotube, nanobelt and nanosponge TiO2 on Ti plates prepared by anodic oxidation method. The plates were characterized by XRD, SEM and electrochemical methods (photocurrent profiles and EIS). Glycerol oxidation experiments were carried out under environmentally friendly conditions using air/water as oxidant and water as solvent under UVA irradiation. Glyceraldehyde, 1,3-dihydroxyacetone, formic acid and CO2 were determined as glycerol products. The effects of photoanode morphology, TiO2 crystallinity, applied potential, pH, solution mixing speed, electrolyte type (and concentration) and gas atmosphere on the glycerol oxidation activity and product selectivity were investigated in detail. In addition, the hole trap effect of methanol was also investigated. Optimum conditions were achieved with anatase phase nanotube structured TiO2 photoanodes in the presence of 20 mM Na2SO4, by applying 1.5 V bias, and 400 rpm solution mixing speed at pH 7 in air atmosphere. Electrocatalytic and photocatalytic experiments were performed in order to compare them, and in the first case no activity was observed, while in the second case it was low. The disappointing results obtained by using the single methods demonstrated the presence of a synergistic effect in the PEC experiments. Moreover, the electrode prepared by simple thermal oxidation of the Ti plate showed no activity in the PEC tests, unlike the structures in which TiO2 nanotubes, nanosponges and nanobelts were present which showed significant activity due to the high specific surface area and their other morphological and structural characteristics.

Porous magnetic nanomaterials have attracted great attention in a variety of applications, particularly in the magnetically targeted and/or controlled release of various species. In this study, a new route was determined to prepare magnetic and mesoporous montmorillonite/magnetite nanocomposites (Mt-Mag NCs). The changes of textural properties of Mt-Mag NCs as a function of the surfactant and silica precursor composition ratios were investigated for the first time. The NCs were then investigated for loading and release performance of 5-Fluorouracil (5-Fu). The NCs, selected for 5-Fu loading and release studies, showed a high surface area about 340.8 m(2)/ g, an average pore diameter of 8.24 nm, and a magnetization saturation of 18.7 emu/g. Interesting new information was also obtained in the method of determining 5-Fu by UV and the method was slightly modified according to obtained results. In vitro release experiments revealed that the NCs showed sustained release profiles of 5-Fu lasting approximately 8 h. Release profiles of 5-Fu from NCs could be fitted by Korsmeyer-Peppas and Hixson kinetics. In vitro cytotoxic study using MCF7 and CRL-4010 cell lines showed that the NCs are good candidates to delivery 5-Fu. Afyon Kocatepe University

In this paper, the first photoelectrocatalytic (PEC) 3-pyridinemethanol oxidation to 3-pyridinemethanal and vitamin B-3 was investigated. To meet this aim, efficient nanotube structured TiO2 on a Ti plate as a photoanode was prepared by an anodic oxidation method in ethylene glycol and characterized by XRD, SEM, and photocurrent techniques. The effect of nanotube morphology, applied potential, Na2SO4 concentration, stirring speed of solution, and pH on the reaction activity and product selectivities were investigated. The TiO2 phase of all of the anodes was mainly the anatase one. The PEC activity, the intensity of the XRD peak and the photocurrent increased by increasing the nanotube length. The activity decreased by decreasing both the Na2SO4 concentration and the applied potential, whereas 3-pyridinemethanal selectivity increased. By increasing the stirring speed of the solution, both the activity and the 3-pyridinemethanal selectivity increased. A lower or no activity was observed for photocatalytic (PC) and electrocatalytic runs, respectively, which were carried out for the sake of comparison. No PC activity was obtained in the presence of N-2, but PEC reactions in the presence of N-2 were faster than those in the presence of O-2. The produced 3-pyridinemethanal in both N-2 and O-2 atmosphere was reduced at the cathode in the PEC reaction, but its oxidation appeared to be much more favourable. The PC reactions could not be carried out under acidic conditions, whilst the PEC ones could be performed in the pH range of 2-12. Moreover, the results indicate that the PEC method allows higher conversions and selectivities to vitamin B-3 to be obtained at pH 7 with respect to those reported in the literature.

This chapter reports on some characterization techniques that are commonly used for catalysts and photocatalysts. Brunauer–Emmett–Teller (BET), scanning electron microscopy (SEM), Fourier-transform infrared spectroscopy (FTIR), UV–visible (UV–Vis), photoluminescence (PL), and electrochemical characterization techniques are presented with experimental details and actual case studies from literature are discussed. The chapter starts with adsorption phenomena on (photo)catalysis and adsorption isotherms are presented. Then BET analysis technique and its applications in (photo)catalysis are explained. Morphological properties (SEM), functional groups, and the interaction of substrate (and intermediates) with the catalyst under dark or under irradiation are discussed using the FTIR technique. The discussion moves on with estimation of band-gap energies and oxidation states of loaded or metal-doped catalysts (through UV–Vis), and to the identification of impurity/defects levels and the investigation of recombination mechanisms by PL. Finally, as electrochemical characterizations, linear sweep and cyclic voltammetry, chronoamperometry (photocurrent), electrochemical impedance spectroscopy, and Fermi level estimation are presented. Special attention is given to comparative assessment between catalysts and photocatalysts, for both powder and supported samples.

N-doped anatase/rutile photocatalysts were prepared by a sol-gel method, using TiCl4 as TiO2 precursor and urea as N-dopant source. The catalysts required a thermal treatment at temperature higher than 300 degrees C to achieve actual nitrogen doping; this treatment also allowed obtaining crystalline and hydrophobic samples. Moreover, nitrogen doping modified the surface of samples by increasing the anatase to rutile phase ratio and hydrophilicity. The catalysts were characterized by BET specific surface area, XRD, ESEM, TGA, FT-IR, DRS and XPS measurements, with particular attention to the assessment of the N-doping effect. It was found that XPS analysis should be used together with DRS and FT-IR to discriminate whether N had been incorporated in TiO2 lattice or N species had just adsorbed on the TiO2 surface. Moreover, XPS analysis could be also used for determining the crystallinity of TiO2. The photocatalytic activity of the samples was tested for the partial oxidation of 4-methoxybenzyl alcohol to p-anisaldehyde in water under near-UV, visible, UV-visible and simulated solar light, respectively. Commercial (Degussa P25) and undoped home-prepared TiO2 anatase-rutile catalysts were also used for comparison. The results show that N-doping improves absorption of visible light by the catalysts, but the reaction rate does not increase accordingly. Selectivity was higher in the presence of poorly crystallized catalysts, whereas doping seemed to have a slightly improving effect.

Nanotube structured TiO2 on Ti surface were prepared in ethylene glycol (Ti/TiO2NTEG) medium by anodic oxidation method with different times and then the plates were calcinated at different temperatures. Non-nanotube structured Ti/TiO2, prepared by thermal oxidation method, and nanotube structured TiO2 on Ti plate in hydrogen fluoride solution were also prepared for comparison. Pt loaded Ti/TiO2NTEG photoanodes were also prepared by cyclic voltammetry method with different cycles and the optimum loaded Pt amount was determined. Photoanodes were characterized by using X-ray Diffraction (XRD), Scanning Electron Microscopy-Energy-Dispersive X-ray Analysis (SEM-EDX), and photocurrent methods. XRD analyses proved that almost all TiO2 is in anatase phase. SEM analyses show that nanotubes and Pt nanoparticles on nanotube surface are dispersed quite homogeneously. The longest nanotubes were obtained in the ethylene glycol medium and the nanotube length increased by increasing applied anodic oxidation time. In addition, a linear correlation between nanotube length and XRD peak intensity was found. Moreover, SEM-EDX and XRD analyses evidence that Pt nanoparticles on nanotube surface are metallic and in cubic structure. Photoelectrocatalytic degradation of paraquat was performed using the prepared photoanodes. Moreover, electrocatalytic and photocatalytic degradations of paraquat were also investigated for comparison, however lower activities were observed. These results evidence that the photoanodes show a significant synergy for photoelectrocatalytic activity.

Selective photocatalytic oxidation of 3-pyridinemethanol to 3-pyridinemethanal and vitamin B-3 by using pristine and Pt loaded home prepared (HP) rutile and commercial TiO2 photocatalysts, under UV, UV-vis and visible irradiations in water, was performed in friendly environmental conditions. The photocatalysts were characterized by XRD, SEM-EDAX, BET, DRS, XPS and TGA techniques. The influence of pH on reactivity and total selectivity to 3-pyridinemethanal and vitamin B3 was studied. Under very acidic conditions (pH = 2) no or low activity (depending on photocatalyst) was observed, whereas by increasing the pH from 4 to 12 very high total selectivity was achieved. The Pt loading was beneficial for selectivity whereas the reactivity was positively affected only for crystalline HP sample. This last sample showed good activity under visible irradiation, exhibing an about 4 times higher conversion than the other samples. The influence of the position of the benzylic group in pyridine (2-pyridinemethanol and 4-pyridinemethanol) was also studied. The results showed that to synthesize vitamin B3 in green conditions the photocatalyst should be poorly crystalline or Pt loaded. (C) 2016 Elsevier B.V. All rights reserved.

Photoelectrocatalytic (PEC) synthesis of 2,5-furandicarbaldehyde (FDC) from 5-(hydroxymethyl)-2-furaldehyde (HMF) has been performed in water by using TiO2 films on Ti layer prepared by thermal annealing of Ti (Ti/TiO2) and TiO2 nanotube on Ti (Ti/TiO2NT) prepared by anodic oxidation as photoanodes. The latter ones showed better activity. In order to improve both activity and selectivity, Ti/TiO2NT was loaded with Pt by photoreduction method. 5-Formyl-2-furoic acid (FFA) was also produced by using Pt loaded Ti/TiO2NT photoanodes. The photoanodes were characterised by using XRD, SEM and XPS techniques. Allotropic phase of TiO2 photoanodes was mainly rutile, whereas trace amounts of anatase phase were found in some samples of TiO2 nanotube photoanodes. The distribution of TiO2 nanotubes on Ti are well organised. In addition, primary particle sizes of TiO2 were increased by increasing thermal treatment temperature; however primary particle sizes of TiO2 in Ti/TiO2NT are higher than that of other samples. The photoanode preparation temperature, bias and medium pH were optimised by following PEC HMF oxidation reaction. Photocatalytic and electrocatalytic HMF oxidations were also performed for comparison and negligible activities were observed. Finally efficient Pt loaded Ti/TiO2NT photoanodes were investigated for PEC selective and active FDC (selectivity up to 40%) and FFA (selectivity up to 18%) syntheses in environmental friendly conditions. (C) 2016 Elsevier B.V. All rights reserved.

The derivatives of styrene monomer, 4-chlorophenyl-4-vinylbenzyl ether (M1), 4-methoxyphenyl-4-vinylbenzyl ether (M2), 4-ethylphenyl-4-vinylbenzyl ether (M3) and 1-naphtylphenyl-4-vinylbenzyl ether (M4) were synthesized. The normal free radical polymerization of monomers in 1,4-dioxane were performed by using 2,2'-azobisisobutyronitrile as an initiator at 65 A degrees C. The monomers and their homopolymers were characterized by FT-IR, NMR and elemental analyses measurements. The thermal stability of polymers was investigated by thermogravimetric and differential scanning calorimetric analysis. Thermal degradation activation energies of the polymers were calculated by the Ozawa and Kissinger methods. In addition, photo-stability tests of the polymers under near-UV irradiation were performed.

A new type of styrene monomer, 1-{4-[(4-vinylbenzyl)oxy]phenyl}ethanone (VBOPE), was synthesized. The oxime, phenylhydrazone, toluol-4-sulfonic acid hydrazone, and thiosemicarbazone (TSC) derivatives of VBOPE were prepared with hydroxylamine hydrochloride, phenylhydrazine, toluol-4-sulfonic acid hydrazine, and TSC hydrochloride, respectively. Radical homopolymerization of the monomers were prepared at 65°C in 1,4-dioxane solution with benzoylperoxide as an initiator. The compounds was characterized with Fourier transform infrared and NMR techniques. The thermal properties of polymers were investigated with thermogravimetric analysis and differential scanning calorimetry. The activation energies of the thermal degradation of the polymers were calculated with the Ozawa and Kissinger method. The antibacterial and antifungal effects of the monomer and the polymer and its derivatives were also investigated on various bacteria and fungi. POLYM. ENG. SCI., 2013. © 2012 Society of Plastics Engineers

It has been recently reported by Palmisano et al. (2015) [1] that the oxidation of 2-methoxybenzyl alcohol (2-MBA) to 2-methoxybenzaldehyde (2-MBAD) proceeds in water under near-UV light with an unexpected catalytic effect of 2-MBAD. In order to investigate the catalytic role of aldehyde in photolytic oxidation of ortho-substituted benzyl alcohols (OSBAs), reactivity runs were carried out with 2-methylbenzyl alcohol (2-MeBA), 2-nitrobenzyl alcohol (2-NBA), 2-hydroxybenzyl alcohol (2-HBA) and 2-chlorobenzyl alcohol (2-CIBA) in the absence and in the presence of their corresponding aldehyde. None of those alcohols showed a measurable oxidation rate even in the presence of their aldehydes but 2-NBA was oxidised very fast, although no corresponding carbonyl product was obtained. The possible catalytic role of 2-MBAD was investigated for the photolytic oxidation of 4-methoxybenzyl alcohol (4-MBA), 4-nitrobenzyl alcohol (4-NBA), 2-CIBA, 2-HBA, 2-MeBA and ferulic acid (FA). The results showed that 2-MBAD acts as a catalyst only for 4-MBA, 2-HBA and FA. The photocatalytic oxidation of OSBAs in the presence of powdered TiO2 has been also carried out in order to investigate the mutual influences, if any, between homogeneous and heterogeneous processes. The reactivity runs were carried out with TiO2 photocatalyst in water and under near-UV irradiation; a home-prepared (HP) TiO2 sample was used along with Degussa P25. HP catalyst showed the best performance: the 2-MBA half-life time was 5 times smaller and the selectivity to aldehyde 13 times higher than in the presence of Degussa P25. (C) 2016 Elsevier B.V. All rights reserved.

WOS: 000382184900011, PubMed ID: 27506715, Pencil graphite electrodes modified with Co(II), Ni(II), Cu(II) and Fe(II) metallophthalocyaninetetrasulfonates (MePcTSs) were investigated for an electrochemical determination of bisphenol A (BPA). The electrochemical performances of the modified electrodes for different pH values in phosphate and the Britton-Robinson buffers were determined by cyclic voltammetry; the electrode performances were better in the Britton-Robinson buffer. NiPcTS and CoPcTS modifications of the electrodes had remarkable enhancements on their performances. The differential pulse voltammetry parameters for the electrodes were optimized, and we found that the electrochemical response versus the concentration of BPA is linear from 5.0 x 10(-7) to 1.0 x 10(-5) M for the NiPcTS and CoPcTS modified electrodes. The detection limits of these modified electrodes are 2.9 x 10(-7) and 4.3 x 10(-7) M, respectively, and the effects of interfering species are less than 5%. The results show that NiPcTS and CoPcTS modified pencil graphite electrodes could be used for electrochemical determinations of BPA for analytical purposes., Scientific Research Project Council of Afyon Kocatepe University (BAP Project) [11.FEN.BIL.01], The authors thank the Scientific Research Project Council of Afyon Kocatepe University (BAP Project Number: 11.FEN.BIL.01) for financial support and Dr. Justin Beck (Pennsylvania State University) for his useful suggestions.

The free radical copolymerization of 2-oxo-2-[(4-sulfamoylphenyl)amino]ethyl-2-methylpropenoate (SAEMA) with 4-methyl-2-oxo-2H-chromen-7-yl-2-methylpropenoate (MCMA) has been carried out in 1, 4-dioxane at 65 °C ± 1 °C and the copolymers were analyzed by Fourier-transform infrared, 1 H-NMR, 13 C-NMR and gel permeation chromatography. 1 H-NMR and elemental analysis was used to determine the molar fractions of SAEMA and MCMA in the copolymers. The monomer-reactivity ratios were calculated according to the general copolymerization equation using Kelen-Tudos and Fineman-Ross linearization methods. The reactivity ratios indicated a tendency toward random copolymerization. The polydispersity indices of the polymers, determined with gel permeation chromatography, suggested a strong tendency for chain termination by disproportionation. The thermal behaviors of copolymers with various compositions were investigated by differential scanning calorimetry and thermogravimetric analysis. The glass-transition temperature of the copolymers increased with increasing MCMA content in the copolymers. Also, the apparent thermal decomposition activation energies were calculated by the Ozawa method with a Shimadzu TGA 60 thermogravimetric analysis thermobalance. All the products showed moderate activity against different strains of bacteria and fungi. The photochemical properties of the polymers were investigated by UV spectra.

In this work, poly(2-fluoroaniline), poly(2-chloroaniline), poly(2-methylaniline), and poly(N-ethylaniline) were prepared by a self-assembly method using an oxidizing system consisting of a dopant anion, p-toluene sulfonate with ammonium peroxydisulfate. The effects of substituents on the surface morphology, conductivity, molecular weight, spectral and thermal properties of the polymers were studied. SEM results revealed that the surface morphology of the resulting polymers changed from nanofiber to spherical structure by changing the substituent on the aniline monomers. The structure and properties of these conducting films were characterized by FTIR, UV-vis, elemental analysis, TGA, conductivity, and cyclic voltammetry. The polymer films show electroactivity in monomer free solution. Molecular weight of the polymers was determined by gel permeation chromatography. The dry electrical conductivity values of the substituted-polyanilines were found to be lower than that of PANI. The results revealed that the molecular structures of the polymers were similar to those of the emeraldine form of polyaniline. © 2009 Wiley Periodicals, Inc. J Appl Polym Sci, 2010

WOS: 000259735700030, PubMed ID: 27873840, A molecularly imprinted polymer (MIP) polypyrrole (PPy)-based film was fabricated for the determination of ascorbic acid. The film was prepared by incorporation of a template molecule (ascorbic acid) during the electropolymerization of pyrrole onto a pencil graphite electrode (PGE) in aqueous solution using a cyclic voltammetry method. The performance of the imprinted and non-imprinted (NIP) films was evaluated by differential pulse voltammetry (DPV). The effect of pH, monomer and template concentrations, electropolymerization cycles and interferents on the performance of the MIP electrode was investigated and optimized. The molecularly imprinted film exhibited a high selectivity and sensitivity toward ascorbic acid. The DPV peak current showed a linear dependence on the ascorbic acid concentration and a linear calibration curve was obtained in the range of 0.25 to 7.0 mM of ascorbic acid with a correlation coefficient of 0.9946. The detection limit (3 sigma) was determined as 7.4x10(-5) M (S/N=3). The molecularly-imprinted polypyrrole-modified pencil graphite electrode showed a stable and reproducible response, without any influence of interferents commonly existing in pharmaceutical samples. The proposed method is simple and quick. The PPy electrodes have a low response time, good mechanical stability and are disposable simple to construct., Anadolu University Research Fund [031064], Financial support from the Anadolu University Research Fund (Project No: 031064) is gratefully acknowledged.

WOS: 000251228600009, Preparation of a molecularly imprinted polymer (MIP) film and its recognition property for paracetamol are investigated. The polypyrrole (PPy) film was prepared by the cyclic voltammetric deposition of pyrrole (Py) in the presence of a supporting electrolyte (LiClO4) with and without a template molecule (paracetamol) through on a pencil graphite electrode (PGE). The performance of the imprinted and non-imprinted (NIP) films was evaluated by differential pulse voltammetry (DPV). Several important parameters controlling the performance of the PPy was investigated and optimized. The molecularly imprinted film exhibited a high selectivity and sensitivity toward paracetamol. The calibration curve for the DPV peak current observed for paracetamol oxidation versus paracetamol concentration at MIP electrode shows two linear regions. The first region demonstrates linearity over a concentration range of 5 mu M to 0.50 mM with a correlation coefficient of 0.996. The slope of the second linear region was smaller than the first region's slope with a wide concentration range of 1.25-4.5 mM (R-2 = 0.990). The detection limit (3 sigma) of paracetamol is 7.9 x 10(-7) M (S/N = 3). Molecularly imprinted polypyrrole modified pencil graphite electrode showed a stable and reproducible response without any influence of interferents commonly existing in pharmaceutical samples

The photoelectrocatalytic partial oxidation of 4-methoxybenzyl alcohol in aqueous solution irradiated by near-UV light was carried out in a three-electrode batch reactor. TiO2 films were either deposited by dip-coating of a TiO2 sol onto a Ti foil and subsequent calcination or generated on Ti plates by thermal oxidation in air at 400-700 degrees C. The effects of the anode preparation method and bias potential values on conversion and selectivity to the corresponding aldehyde were investigated. The photoelectrocatalytic results were compared with the photocatalytic and electrocatalytic ones. The results indicated that no reaction occurred during the electrocatalytic experiments, whereas the photocatalytic reactivity was positively influenced by the application of a small bias (0.75 V vs. saturated calomel electrode). By applying the previous bias the highest initial degradation rates, r(0), and selectivities to 4-methoxybenzaldehyde, S, were obtained in photoelectrocatalytic experiments by using Ti plate calcined at 500 degrees C (r(0) = 0.1507 mM h(-1), S=85%) or TiO2 film prepared by dip-coating and calcined at 700 degrees C (r(0) = 0.1339 mM h(-1), S=90%). In order to investigate the influence of the substituent groups on reactivity and selectivity, photoelectrocatalytic runs with benzyl alcohol, 2-methoxybenzyl alcohol, 3-methoxybenzyl alcohol, 2,4-dimethoxybenzyl alcohol, 2,3,4-trimethoxybenzyl alcohol, 4-nitrobenzyl alcohol and 4-hydroxybenzyl alcohol have been performed. The selectivity and reactivity values increased by increasing the electron-donor properties of the substituent groups. This positive effect, however, was obtained only if the electron-donor group is in para or ortho position with respect to the alcoholic group. (C) 2012 Elsevier B.V. All rights reserved.

Three derivatives of styrene monomer, 4-chlorophenyl-4-vinylbenzyl ether (I), 4-methoxyphenyl-4-vinylbenzyl ether (II) and 4-ethylphenyl-4-vinylbenzyl ether (III) were synthesized. The synthesized two novel compounds (I and III) and one with undefined structural features were identified by experimental spectroscopic techniques and density functional approach. The optimized geometrical structure, vibrational and electronic transitions along with chemical shifts of those compounds were presented in this study. The vibrational spectra of investigated compounds were recorded in solid state with FT-IR spectrometry in the range of 4000-400 cm-1. The computational vibrational wavenumbers and also ground state equilibrium conformations were carried out by using density functional method with 6-311++G(d,p) basis set. Assignments of the fundamental vibrational modes were examined on the basis of the measured data and total energy distribution (TED) of the vibrational modes, calculated with scaled quantum mechanical (SQM) method. Isotropic chemical shift of hydrogen and carbon nuclei were investigated via observed 1H and 13C NMR spectra in deuterated DMSO solution and predicted data applied with gauge-invariant atomic orbitals (GIAOs) method. The UV absorption spectra of monomers were observed in the range of 200-800 nm in ethanol, and time dependent DFT method was used to obtain the electronic properties. A detailed description of spectroscopic behaviors of compound was given based on the comparison of experimental measurements and theoretical computations. © 2013 Elsevier B.V. All rights reserved.

WOS: 000269278300015, PubMed ID: 19493669, A potentiometric detector, based on electrodeposition of polypyrrole onto Pt electrode, was investigated in this study. The chromatographic performance of the PPy detector was investigated in ion chromatography. The resulting PPy detector exhibited good performance for AA determination with a wide linear range (1.0 x 10(-6) to 1.0 x 10(-2) M), a highly reproducible response (R.S.D. of 2.45%), without any interference and long-term stability. The calculated detection limit was 7.0 x 10(-5) mM at 3 sigma. The calibration results showed good Nernstian behavior and also satisfactory low detection limit. In order to verify the reliability of the PPy detector, it was applied to the determination of AA in pharmaceutical samples. The results were satisfactory and agreed closely with the manufacturers' stated contents. The PPy electrode can be used as an alternative novel potentiometric detector material for determination of AA in standards and pharmaceutical samples, Anadolu University Research Projects Commission [031064], Financial support of Anadolu University Research Projects Commission (Project No.: 031064) is gratefully acknowledged. Y.S. would like to thank Prof Dr. Servet Turan and Res. Asst. Hilmi Yurclakul for taking the SEM pictures of the polymer films.

WOS: 000261262000002, PubMed ID: 18599285, An enzymeless biosensor, based on electrode position of overoxidized polypyrrole nanofiber onto pencil graphite electrode and modified with cobalt(II) phthalocyanine tetrasulfonate (CoPcTS), was investigated in this study. CoPcTS showed electrocatalytic activity for the oxidation of glucose in alkaline solution. The electrochemical performance of the modified electrodes was investigated by differential pulse voltammetric (DPV) method. The resulting biosensor exhibited excellent performance for glucose determination with a wide linear range (0.25-20 mM), a highly reproducible response (R.S.D. of 2.7%), low percentage of the interferences and long-term stability. The calculated detection limit was 0.1 mM at 3 sigma. in order to verify the reliability of the biosensor, it was applied to the determination of glucose in serum samples. The results were satisfactory and agreed closely with those measured in a hospital, Anadolu University Research Found [031064, 051060], Financial support of Anadolu University Research Found (Project Nos.: 031064 and 051060) is gratefully acknowledged. YS would like to thank Prof. Dr. Servet Turan and Res. Asst. Hilmi Yurdakul for taking the SEM pictures of the polymer films.

WOS: 000292842100020, The electrochemical behaviours of five sulfonamides (sulfanilamide, sulfadiazine, sulfamerazine, sulfamonomethoxine, sulfamethoxazole) were investigated with overoxidized polypyrrole (OPPy) modified pencil graphite electrodes. The performance of the OPPy electrode was evaluated by differential pulse voltammetry in Britton-Robinson buffer solutions prepared in different ratio of acetonitrile-water binary mixture, between pH 1.5 and 7.0. The highest anodic signals of sulfonamides were obtained in Britton-Robinson buffer solution prepared in 50% (v/v) acetonitrile-water at pH 2.5 and 3.0. The OPPy electrodes exhibited good performance for sulfonamides with wide linear ranges (approximate to 10(-5)-10(-3) M), highly reproducible responses (RSD% = 0.9990). The calculated limits of detection were similar to 10(-6) or 10(-7) M at 3 sigma. In order to verify the reliability of the OPPy electrode as a sensor, it is used for determination of sulfamethoxazole in a pharmaceutical tablet. The recovery was found as 95.96% with the RSD% of 0.68. The overoxidized polypyrrole modified pencil graphite electrode showed a stable and reproducible response without any influence of interferent commonly existing in pharmaceutical containing sulfamethoxazole., Suleyman Demirel University [1202-D-05]; Anadolu University [031064], Financial support from Suleyman Demirel University (Projects No: 1202-D-05) and Anadolu University (Project No: 031064) Research Funds is gratefully acknowledged.