Browsing by Author "Kanberoglu, Gulsah Saydan"

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Advances in Nanomaterial Based Optical Biosensing and Bioimaging of Apoptosis Via Caspase-3 Activity: a Review
(Springer Wien, 2018) Khalilzadeh, Balal; Shadjou, Nasrin; Kanberoglu, Gulsah Saydan; Afsharan, Hadi; de la Guardia, Miguel; Charoudeh, Hojjatollah Nozad; Rashidi, Mohammad-Reza
Caspase-3 plays a vital role in intrinsic and extrinsic pathways of programed cell death and in cell proliferation. Its detection is an important tool for early detection of some cancers and apoptosis-related diseases, and for monitoring the efficacy of pharmaceuticals and of chemo- and radiotherapy of cancers. This review (with 72 references) summarizes nanomaterial based methods for signal amplification in optical methods for the determination of caspase-3 activity. Following an introduction into the field, a first large section covers optical assays, with subsections on luminescent and chemiluminescence, fluorometric (including FRET based), and colorimetric assays. Further section summarize methods for bioimaging of caspase-3. A concluding section covers current challenges and future perspectives.
Application of Deep Eutectic Solvent in Ultrasound-Assisted Emulsification Microextraction of Quercetin From Some Fruits and Vegetables
(Elsevier Science Bv, 2019) Kanberoglu, Gulsah Saydan; Yilmaz, Erkan; Soylak, Mustafa
A deep eutectic solvent ultrasound-assisted emulsification microextraction (USAEME-DES) procedure for the separation and preconcentration of quercetin in vegetable and fruit samples has been established. An alcohol-based extraction has been applied as sample pre-treatment step prior to microextraction procedure. Quercetin was extracted into DES phase (tetrabutylammonium chloride: decanoic acid (TBACI-DA, 1:3 M ratio) and analyzed by UV-VIS spectrophotometry at 370 nm. For the quantitative recoveries of quercetin, optimal pH, sample solution volume, volume and kind of DES, and ultrasonication time were 3.0, 15 mL, 250 mu L. of 1:3 M ratio of TBACI-DA acid and 5 min, respectively. The influences of matrix constituents were also studied. The developed method has a limit of detection (LOD) of 18.8 mu g L-1 and a relative standard deviation (RSD) of 5.1%. The developed procedure was applied to analysis of vegetable and fruit samples, which prepared by alcohol based extraction step. (C) 2019 Elsevier B.V. All rights reserved.
The Calculation of Some Gamma Shielding Parameters for Semiconductor Cspbbr3
(Amer inst Physics, 2017) Oto, Berna; Gulebaglan, Sinem Erden; Kanberoglu, Gulsah Saydan
Recently, researchers produced perovskites structures used in optoelectronic devices as substrates, sensors. CsPbBr3 crystal is found in the cubic perovskite structure and its space group is Pm-3m. CsPbBr3 is a developing material for detection of X- and gamma-ray radiations and the knowledge of the attenuation parameters of CsPbBr3 crystal is important. In this study, some photon shielding parameters such as mass attenuation coefficient (mu(p)), effective atomic number (Z(eff)), and electron density (N-el) have been investigated for CsPbBr3 compound. The theoretical values of mu(p) have been calculated in the energy range from 1 keV to 100 GeV using WinXCom computer code and these values have been used in order to calculate the values of Z(eff) and N-el in the same energy range.
Chromium Based Metal-Organic Framework Mil-101 Decorated Palladium Nanoparticles for the Methanolysis of Ammonia-Borane
(Royal Soc Chemistry, 2020) Caner, Nurdan; Yurderi, Mehmet; Bulut, Ahmet; Kanberoglu, Gulsah Saydan; Kaya, Murat; Zahmakiran, Mehmet
Palladium nanoparticles stabilized by an MIL-101 metal-organic framework (Pd@MIL-101) are synthesized by a novel synthesis approach. A Pd@MIL-101 catalyst facilitates H(2)generation from the methanolysis of ammonia-borane with record catalytic activity (TOF = 1080 min(-1)) at room temperature. Moreover, the exceptional stability of Pd@MIL-101 makes it a reusable heterogeneous catalyst in this catalytic transformation.
Cobalt Nanoparticles Supported on Alumina Nanofibers (co/Al2o3): Cost Effective Catalytic System for the Hydrolysis of Methylamine Borane
(Pergamon-elsevier Science Ltd, 2019) Baguc, Ismail Burak; Yurderi, Mehmet; Bulut, Ahmet; Celebi, Metin; Kanberoglu, Gulsah Saydan; Zahmakiran, Mehmet; Baysal, Akin
Amongst different amine-borane derivatives, methylamine-borane (CH3NH2BH3) seems to be one of the capable aspirants in the storing of hydrogen attributable to its high hydrogen capacity, stability and aptitude to generate hydrogen through its catalytic hydrolysis reaction under ambient conditions. In this research paper, we report that cobalt nano-particles supported on alumina nanofibers (Co/Al2O3) are acting as active nanocatalyst for catalytic hydrolysis of methylamine-borane. Co/Al2O3 nanocatalyst was fabricated by double-solvent method followed with wet-chemical reduction, and was characterized by utilizing various spectroscopic methods and imaging techniques. The results gathered from these analyses showed that the formation Al2O3 nanofibers supported cobalt(0) nanoparticles with a mean diameter of 3.9 +/- 1.2 nm. The catalytic feat of these cobalt nanoparticles was scrutinized in the catalytic hydrolysis of methylamine-borane by considering their activity and durability performances. They achieve releasing of 3.0 equivalent of H-2 via methylamine-borane hydrolysis at room temperature (initial TOF = 297 mol H-2/mol metal x h). Along with activity the catalytic durability of Co/Al2O3 was also studied by carrying out recyclability tests and it was found that these supported cobalt nanoparticles have good durability during the course of the catalytic recycles so that Co/Al2O3 preserves almost its innate activity at 5th catalytic recycle. The studies presented here also contains kinetic investigation of Co/Al2O3 catalyzed methylamine borane hydrolysis depending on the temperature, cobalt and methylamine borane concentrations, which were used to define rate expression and the activation energy of the catalytic reaction. (C) 2019 Hydrogen Energy Publications LLC. Published by Elsevier Ltd. All rights reserved.
Complete Dehydrogenation of Hydrazine Borane on Manganese Oxide Nanorod-Supported Ni@ir Core-Shell Nanoparticles
(Amer Chemical Soc, 2020) Yurderi, Mehmet; Top, Tuba; Bulut, Ahmet; Kanberoglu, Gulsah Saydan; Kaya, Murat; Zahmakiran, Mehmet
Hydrazine borane (HB; N2H4BH3) has been considered to be one of the most promising solid chemical hydrogen storage materials owing to its high hydrogen capacity and stability under ambient conditions. Despite that, the high purity of hydrogen production from the complete dehydrogenation of HB stands as a major problem that needs to be solved for the convenient use of HB in on-demand hydrogen production systems. In this study, we describe the development of a new catalytic material comprised of bimetallic Ni@Ir core-shell nanoparticles (NPs) supported on OMS-2-type manganese oxide octahedral molecular sieve nanorods (Ni@Ir/OMS-2), which can reproducibly be prepared by following a synthesis protocol including (i) the oleylamine-mediated preparation of colloidal Ni@Ir NPs and (ii) wet impregnation of these ex situ synthesized Ni@Ir NPs onto the OMS-2 surface. The characterization of Ni@Ir/OMS-2 has been done by using various spectroscopic and visualization techniques, and their results have revealed the formation of well-dispersed Ni@Ir core-shell NPs on the surface of OMS-2. The catalytic employment of Ni@Ir/OMS-2 in the dehydrogenation of HB showed that Ni-0.22@Ir-0.78/OMS-2 exhibited high dehydrogenation selectivity (>99%) at complete conversion with a turnover frequency (TOF) value of 2590 h(-1) at 323 K, which is the highest activity value among all reported catalysts for the complete dehydrogenation of HB. Furthermore, the Ni-0.22@Ir-0.78/OMS-2 catalyst enables facile recovery and high stability against agglomeration and leaching, which make it a reusable catalyst in the complete dehydrogenation of HB. The studies reported herein also include the collection of wealthy kinetic data to determine the activation parameters for Ni-0.22@Ir-0.78/OMS-2-catalyzed dehydrogenation of HB.
Developing a New and Simple Ultrasound-Assisted Emulsification Liquid Phase Microextraction Method Built Upon Deep Eutectic Solvents for Patent Blue V in Syrup and Water Samples
(Elsevier Science Bv, 2019) Kanberoglu, Gulsah Saydan; Yilmaz, Erkan; Soylak, Mustafa
In this study, Deep Eutectic Solvents (DESs) were utilized for ultrasound -assisted emulsification liquid phase microextraction (UA-ELPME) of Patent Blue V in syrup and water samples. Patent Blue V in sample solution of pH 4.0 was extracted into DES phase prepared from choline chloride and phenol. Concentration of Patent Blue V in final DES phase was measured at 627.5 nm with Uv-Vis spectrophotometry. Sample volume, pH, matrix effect, volume and type of DES, ultrasonication and centrifugation times were investigated and optimized. The developed UA-ELPME method presents a limit of detection (LOD) of 0.37 mu g L-1, preconcentration factor of 15 and a relative standard deviation (RSD, %) of 6.0% under the optimum conditions. The validation was carried out with standard addition-recovery experiments for syrup and water samples. The obtained recovery results showed that the developed UA-ELPME method was applicable for routine Patent Blue V analysis in syrup and water samples.
Developing a Potentiometric Sunset Yellow Selective Electrode and Its Applications
(2020) Aydın, Mehmet; Kanberoglu, Gulsah Saydan
We developed a potentiometric ion-selective electrode (ISE) for detecting the food dye sunsetyellow (SY). Sunset yellow-Methyltrioctylammonium chloride ion pairs were synthesized.The ion pair that was synthesized was employed as ionophorein the configuration of theelectrode membrane. PVC membrane ion-selective electrodes in various compositions wereproduced using the ion pairs that were synthesized and then, potentiometric performancecharacteristics of these electrodes were investigated. It was determined that the electrode withthe composition of 3.0 % sunset yellow-Methyltrioctylammonium (Sunset-MTOA) ion pair,64.8 % nitrophenyloctyl ether (NPOE), 32.0 % polyvinylchloride (PVC) and 0.2 % potassiumtetrakis (4-chlorophenylborate) (KTpClPB) demonstrated the best potentiometric performanceproperties. The linear range, slope, limit of quantification, pH range, and the response time ofthe electrode were determined as 1.0 × 10-5-5.0 × 10-2 M, 23.6 mV,1.0 × 10-5 M,6.4-9.1, and≈ 5 sec, respectively. The electrode exhibited a highly repeatable potentiometric response.
Development of a Potentiometric Maprotiline-Selective Electrode and Its Application in Pharmaceutical Samples
(Elsevier, 2019) Cavus, Ibrahim; Kanberoglu, Gulsah Saydan
A potentiometric ion selective electrode (ISE) was developed to determine the maprotiline, a tetracyclic pharmaceutical drug substance. Maprotiline-Tetraphenylborate ion pair was synthesized. Elemental analysis results showed that combination rate of Maprotiline-Tetraphenylborate ion pair was 1:1. The synthesized ion pair was used as sensing material in the structure of the electrode membrane. For membrane optimization, Polyvinylchloride (PVC) membrane ion selective electrodes were fabricated in different compositions using the synthesized ion pair and the potentiometric performance properties of these electrodes were investigated. We found that an electrode with a composition of 3.0% Maprotiline-Tetraphenylborate ion pair, 65.0% Dibutylphthalate, 32.0% Polyvinylchloride exhibited the best potentiometric performance properties. The linear working range of this electrode was 1.0 x 10(-5)-1.0 x 10(-2) M and slope in 10-fold concentration change was 55.4 mV; detection limit was 5.0 x 10(-6) M, pH working range was 3-5; and finally response time was 5 s. The electrode has demonstrated a highly repeatable potentiometric response. The maprotiline content of two different pharmaceutical tablets that are used to treat depression was determined using this electrode. The obtained results were compared with the results obtained by the GC method, which is our comparison method. We found that the results obtained using the potentiometric technique is consistent with the results obtained using GC method at 95% confidence level.
Development of a Pvc Membrane Potentiometric Sensor With Low Detection Limit and Wide Linear Range for the Determination of Maprotiline in Pharmaceutical Formulations
(Wiley-v C H verlag Gmbh, 2022) Tekce, Serkan; Subasi, Yaver; Coldur, Fatih; Kanberoglu, Gulsah Saydan; Zahmakiran, Mehmet
Maprotiline (MAP), is an active ingredient of some antidepressants which has been broadly used for the therapy of depression. The overdose of MAP in the treatment of patients with depression can lead to significant side effects, even lethal intoxication. Therefore, it is very important to develop simple, inexpensive, fast and reliable detection methods for MAP in interested samples. In our present study, we have offered a novel poly(vinylchloride) (PVC) membrane maprotiline-selective potentiometric sensor based on a type of MOFs, known as MIL-53(Al), as electroactive ionophore substance. The sensor prepared at the optimum membrane composition exhibited a linear response for maprotiline hydrochloride in the concentration range of 1,0x10(-9) M-1,0x10(-2) M with a slope of 59,1 mV/decade and detection limit of 9,0x10(-10) M. The pH working range of the sensor was determined as 2,0-9,5. The response time of the sensor was very fast and less than 5 s. With these performance features, it has been shown that the current sensor has quite superior features compared to the potentiometric MAP-selective sensor available in the literature. The potentiometric application of the sensor was successfully carried out with the detection of MAP in pharmaceutical tablets containing MAP-HCl.
Development of a Reliable Microrna Based Electrochemical Genosensor for Monitoring of Mir-146a, as Key Regulatory Agent of Neurodegenerative Disease
(Elsevier Science Bv, 2019) Khalilzadeh, Balal; Rashidi, Mohammad; Soleimanian, Alireza; Tajalli, Habib; Kanberoglu, Gulsah Saydan; Baradaran, Behzad; Rashidi, Mohammad-Reza
A MicroRNA (miR) based electrochemical method for quantification of miR-146a, a known biomarker for neurodegenerative disease, was developed. In this bioassay, the capture microRNA (C-miR) was self-assembled on the gold surface and used for quantification of target microRNA (T-miR) of miR-146a. For this purpose, an optimized concentration of C-miR was immobilized on the surface of gold electrode and used for capture of target analyte (T-miR). All of preparation steps were characterized by electrochemical techniques (cyclic voltammetry (CV) and electrochemical impedance spectroscopy (EIS)) and atomic force microscopy (AFM). At the optimized conditions, the linear dynamic range, limit of quantification and relative standard deviation of the proposed bioassay were obtained as 10 pM to 1 mu M, 10 pM and 1.59%, respectively. The unprocessed human serum sample was used as a real sample and the results fully confirm that the designed microRNA based biosensor is capable for detection of miR-146a as neurodegenerative disease biomarker. The developed method offers a more precise and high sensitive tool to be used in clinical applications for early detection of neurodegenerative disease like Alzheimer's and Parkinson. (C) 2019 Elsevier B.V. All rights reserved.
Electrochemical Biosensors as a Novel Platform in the Identification of Listeriosis Infection
(Mdpi, 2023) Mehrannia, Leila; Khalilzadeh, Balal; Rahbarghazi, Reza; Milani, Morteza; Kanberoglu, Gulsah Saydan; Yousefi, Hadi; Erk, Nevin
Listeria monocytogenes (L.M.) is a gram-positive bacillus with wide distribution in the environment. This bacterium contaminates water sources and food products and can be transmitted to the human population. The infection caused by L.M. is called listeriosis and is common in pregnant women, immune-deficient patients, and older adults. Based on the released statistics, listeriosis has a high rate of hospitalization and mortality; thus, rapid and timely detection of food contamination and listeriosis cases is necessary. During the last few decades, biosensors have been used for the detection and monitoring of varied bacteria species. These devices are detection platforms with great sensitivity and low detection limits. Among different types of biosensors, electrochemical biosensors have a high capability to circumvent several drawbacks associated with the application of conventional laboratory techniques. In this review article, different electrochemical biosensor types used for the detection of listeriosis were discussed in terms of actuators, bioreceptors, specific working electrodes, and signal amplification. We hope that this review will facilitate researchers to access a complete and comprehensive template for pathogen detection based on the different formats of electrochemical biosensors.
Electrodeposition of Cerium Oxide Nanoparticles on the Graphenized Carbon Ceramic Electrode (Gcce) for the Sensitive Determination of Isoprenaline in Human Serum by Differential Pulse Voltammetry (Dpv)
(Taylor & Francis inc, 2022) Shafaei, Sepideh; Akbari Nakhjavani, Sattar; Kanberoglu, Gulsah Saydan; Khalilzadeh, Balal; Mohammad-Rezaei, Rahim
Cerium oxide nanoparticles (CeO2) are widely used as the electrocatalyst in solar cells, fuel cells, water splitting, and electroanalytical experiments. Therefore, controlled electrodeposition of CeO2 on the surface of electrodes may improve the performance of electrochemical devices. CeO2 was electrochemically deposited on the surface of a graphenized carbon ceramic electrode (GCCE) for the determination of isoprenaline in biological samples. The pH, temperature, deposition time, and applied potential were optimized for the electrodeposition. According to differential pulse voltammetry, the linear range, detection limit, and sensitivity of the designed assay were from 5 to 310 nM, 3.03 nM and 25.21 x 10(-5 )mu A mu M(-1 )cm(-2), respectively. Easy preparation, low cost, and high production repeatability of the developed CeO2/GCCE suggest further applications. The prepared modified electrode was successfully utilized for the determination of isoprenaline in human serum with satisfactory results.
Flow Injection Potentiometric Determination of Silver(I) in Photographic Film Developing Solution Samples by Polyvinylchloride Membrane Silver(I) Selective Electrode
(Chem Soc Pakistan, 2016) Topcu, Cihan; Coldur, Fatih; Andac, Muberra; Cubuk, Osman; Kanberoglu, Gulsah Saydan; Caglar, Bulent; Isildak, Ibrahim
A polyvinylchloride (PVC) membrane silver(I) selective electrode was developed for the determination of silver(I) ions in photographic film developing solutions. The electrode was embedded into a home-made flow cell and successfully used as a potentiometric detector in a flow injection potentiometric (FIP) system. Under the optimized flow injection conditions, the electrode exhibited a non-Nernstian slope of 67.20 +/- 0.80 mV in the linear range from 1.0x10(-5) to 1.0x10(-1) mol/L (R-2 = 0.9961) and the lowest value for limit of detection (LOD) was calculated as 7.1x10(-6) mol/L. The electrode displayed good sensitivity, selectivity, repeatable and rapid response towards silver(I) ions. Lifetime of the electrode was determined as at least two months in FIP system. The electrode was also successfully applied for the potentiometric determination of silver(I) ions in photographic film developing solution samples in FIP system. The results attained from FIP system were compared with the atomic absorption spectrophotometry (AAS) results by using student's t-test at 95 % confidence level and relative deviation (RD) between the two methods was < 8 %.
Gamma Shielding Properties of Tamoxifen Drug
(Amer inst Physics, 2017) Kanberoglu, Gulsah Saydan; Oto, Berna; Gulebaglan, Sinem Erden
Tamoxifen (MW=371 g/mol) is an endocrine therapeutic drug widely prescribed as chemopreventive in women to prevent and to treat all stages of breast cancer. It is also being studied for other types of cancer. In this study, we have calculated some gamma shielding parameters such as mass attenuation coefficient (mu(rho)), effective atomic number (Z(eff)) and electron density (N-el) for Tamoxifen drug. The values of lip were calculated using WinXCom computer program and then the values of Z(eff) and N-el were derived using lip values in the wide energy range (1 keV - 100 GeV).
Highly Efficient Electrochemical Biosensing Platform in Breast Cancer Detection Based on Mof-Cof@au Core-Shell Like Nanostructure
(Nature Portfolio, 2024) Dezhakam, Ehsan; Vayghan, Roya Faraghi; Dehghani, Sarina; Kafili-Hajlari, Taha; Naseri, Abdolhossein; Dadashpour, Mehdi; Kanberoglu, Gulsah Saydan
Nowadays, rapid and facile diagnosis of cancer using user friendly processes has attracted much attention. In this regard, an electrochemical (EC) biosensor with high sensitivity was fabricated by merging MIL156 MOF@COF nanocomposite with Au nanoparticles for the detection of CA15-3. Herein, metal clusters of MIL-156 as a Metal organic frameworks (MOF) were coated by a crystalline covalent organic frameworks (COF) through covalent bonding and created core-shell-like structures. The active part of the working electrode was modified in two consecutive steps. First, MIL-156 MOF@COF and then Au nanoparticles were electrodeposited on the glassy carbon electrode (GCE). The porosity of nanocomposite has significantly increased the surface area and improved the conductivity. Au nanoparticles also form an acceptable substrate for bonding antibodies due to their high affinity with amino groups. In addition, Au nanoparticles amplify the EC signal of the biosensor with their undeniable conductivity. Nanocomposite was characterized with XRD, SEM, and EDAX techniques. To investigate the proposed biosensor, differential pulse voltammetry (DPV) was used as an analytical technique. The CA15-3 calibration provided a linear range between concentrations of 30 and 100 nU/mL, thus expressing the powerful diagnostic potential of the designed biosensor. Furthermore, the suggested biosensor has been used in serum samples and discriminate breast cancer sufferers from healthy individuals with high confidence levels.
Hydrotalcite Framework Stabilized Ruthenium Nanoparticles (ru/Htal): Efficient Heterogeneous Catalyst for the Methanolysis of Ammonia-Borane
(Tubitak Scientific & Technological Research Council Turkey, 2020) Baguc, Ismail Burak; Yurderi, Mehmet; Kanberoglu, Gulsah Saydan; Bulut, Ahmet
Ruthenium nanoparticles stabilized by a hydrotalcite framework (Ru/HTaL) were prepared by following a 2-step procedure comprising a wet-impregnation of ruthenium(III) chloride precatalyst on the surface of HTaL followed by an ammonia-borane (NH3BH3) reduction of precatalyst on the HTaL surface all at room temperature. The characterization of Ru/HTaL was done by using various spectroscopic and visualization methods including ICP-OES, P-XRD, FTIR, B-11 NMR, XPS, BFTEM, and HRTEM. The sum of the results gained from these analyses has revealed the formation of well-dispersed and highly crystalline ruthenium nanoparticles with a mean diameter of 1.27 +/- 0.8 nm on HTaL surface. The catalytic performance of Ru/HTaL in terms of activity, selectivity, and stability was investigated in the methanolysis of ammonia-borane (NH3BH3, AB), which has been considered as one of the most promising chemical hydrogen storage materials. It was found that Ru/HTaL can catalyse methanolysis of AB effectively with an initial turnover frequency (TOF) value of 392.77 min(-1) at conversion (>95%) even at room temperature. Moreover, the catalytic stability tests of Ru/HTaL in AB methanolysis showed that Ru/HTaL acts as a highly stable and reusable heterogeneous catalyst in this reaction by preserving more than 95% of its initial activity even at the 5th recycle.
Inhibition Effects of Isoproterenol, Chlorpromazine, Carbamazepine, Tamoxifen Drugs on Glutathione S-Transferase, Cholinesterases Enzymes and Molecular Docking Studies
(Taylor & Francis inc, 2021) Turkan, Fikret; Calimli, Mehmet Harbi; Kanberoglu, Gulsah Saydan; Karaman, Muhammet
Nowadays, inhibition of acetylcholinesterase (AChE), butyrylcholinesterase (BChE) and glutathione S-transferases (GSTs) have been a very crucial issue for pharmacological treatments of several disasters. Herein, we investigated inhibition effects of Tamoxifen (TAM), Isoprenaline (ISO), Chlorpromazines (CPZ) and Carbamazepine (CBZ) on GST, AChE, BChE and then molecular structures and active sides of the tested drugs by molecular docking process. The enzyme activity results showed that nearly the whole tested drugs inhibited GST, BChE, AChE efficiently. Chlorpromazine was found to be the best inhibitor for the GST enzyme and the Ki value of this drug was found to be 42.83 +/- 8.52 nM. Besides, Isoproterenol drug with the Ki value of 51.80 +/- 9.44 nM was found to be the most effective inhibitor on the AChE enzyme. Molecular docking studies showed that the receptor-binding sites of GST, AChE, and BChE were found to 1.069, 1.090, and 1.15 of Sitecore and 0.992, 1.113, and 1.217 of Dscore, respectively. The method was validated by doing validation studies and these validations revealed that re-docked ligands located a very closed position with co-crystallized ligand into the active site for all receptors. Calculation studies for determining the possible enzyme inhibition mechanism with the used drugs revealed that amino and aromatic ring in the structure of the drugs used are effective in inhibition reactions. Communicated by Ramaswamy H. Sarma
A Novel Potentiometric Pvc-Membrane Cysteamine-Selective Electrode Based on Cysteamine-Phosphomolybdate Ion-Pair
(Bentham Science Publ Ltd, 2020) Tumur, Merve; Kanberoglu, Gulsah Saydan; Coldur, Fatih
Background: Cysteamine is used as an orphan drug in the treatment of cystinosis to prevent long-term cystine accumulation in lysosomes. Dosing in cysteamine treatment is extremely important and overdose may cause some side effects. Up to now, various analytical methods have been used for cysteamine determination. Many of these methods require sophisticated instniments, expert operators, time-consuming measurement procedures and manipulation steps, expensive supplies and long analysis time. Aims and Objective: The present study deals with the development of a potentiometric PVC-membrane cysteamine-selective electrode based on an ion-pair of cysteamine and its application in a pharmaceutical formulation. Methods: Cysteamine (Cys)-Phosphomolybdate (PM) ion-pair was synthesized by mixing the equal volumes of 10-2 M Cysteamine HC1 and sodium phosphomolybdate aqueous solutions. The obtained precipitate was used as ionophore in the structure of PVC-membrane. Results and Discussion: The electrode exhibited a linear response in the concentration range of 1.0x10(-1).0 10(-5) M cysteamine with a slope of 51,7 mV per decade and detection limit of 1.0x10-5 M. The potentiometric response of the electrode Was very rapid (5 s), adequately repeatable, stable and selective. pH working range and life-time of the electrode were also determined as 3.0-7.0 and 25 days, respectively. Conclusion: A PVC-membrane cysteamine selective electrode was easily prepared. Cysteatnine determination in a pharmaceutical formulation was performed. Analysis results indicated that it can be successfully used in dnig quality control laboratories for routine analysis of cysteamine in pharmaceutical preparations alternative to more sophisticated, expensive and time-consuming analytical methods.
Potansiyometrik Raktopamin Seçici Elektrot Geliştirilmesi ve Uygulaması
(2019) Kanberoglu, Gulsah Saydan
Bu çalışmada, raktopamin miktarını belirlemek için potansiyometrik iyon seçici bir elektrot (ISE) geliştirildi. Raktopamin, aslında solunum yolu hastalıklarının tedavisi için geliştirilmiş ve veterinerlikte ve insan tıbbında tokolitik, bronkodilatör ve kalp tonik olarak kullanılmakta olan ß2-adrenerjik agonist özelliklere sahip bir feniletanolamindir (1). Raktopamin-Tetrafenilborat iyon çifti sentezlendi. Sentezlenen iyon çifti, elektrot membranının yapısında iyonofor olarak kullanıldı. Membranların optimizasyonu için, PVC membran iyon seçici elektrotları, sentezlenen iyon çiftleri kullanılarak çeşitli bileşimlerde üretildi ve bu elektrotların potansiyometrik performans özellikleri araştırıldı. % 5 Rak-TPB +% 32 PVC +% 62,6 DBF +% 0,4 KTpClPB (Potasyum tetrakis (4-klorofenil borat) bileşimine sahip olan elektrodun en iyi potansiyometrik performans özelliklerini gösterdiği tespit edildi. Bu elektrodun doğrusal çalışma aralığı, eğimi, tayin limiti, pH aralığı ve cevap zamanı aralığı sırasıyla 1.0 x $10^{-5}$ -1.0 x $10^{-1}$ M; 51.0 mV; 1.0 x $10^{-5}$ M, 3.0-5.0 ve <5s olarak belirlendi. Elektrot son derece tekrarlanabilir bir potansiyometrik cevap gösterdi. Raktopamin seçici elektrodu domuz yemine uygulandı.