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Öğe New voltammetric strategy for determination and electrochemical behaviors of metformin by pencil graphite electrode in the NaOH(Indian Chemical Society, 2020) Altunkaynak, Yalçın; Yavuz, Ömer; Levent, AbdulkadirMetformin(MET), an oral antidiabetic drug commonly used in the treatment of diabetes, is a drug that increases insulin sensitivity in the biguanide group [1]. MET shows its pharmacological effect by lowering the glucose level in the blood. In the literature research, there are studies using electrochemical techniques for the analysis of MET in biological fluid and drug forms[1-6]. In this study, the electrochemical properties of MET, one of the drugs used in the treatment of diabetes, were performed using a pencil graphite electrode in NaOH (0.1 M) solution. This compound was recorded with an irreversible and diffusion controlled adsorption oxidation peak at approximately +1.28 V by cyclic voltammetry. With square wave stripping voltammetry, it was observed that the peak current signals of MET in the concentration range of 2.76-24.8 µM in 0.1M NaOH solution increased linearly. At a concentration of 2.76 µM (n = 9), the limit of detection and relative standard deviation were calculated as 9.03 nM (1.495 ngmL-1 ) and 3.25 %, respectively. This method has been successfully applied for MET analysis in pharmaceutical preparations and urine samples without any separation.Öğe Extraction of lanthanum and cerium from a bastnasite ore by direct acidic leaching(TMMOB Maden Mühendisleri Odası, 2020-06-01) Özsaraç, Şafak; Kurşunoğlu, Sait; Hussaini, Shokrullah; Gökçen, Hasan Serkan; Kaya, Muammer; Altıner, Mahmut; Top, SonerThe extraction of lanthanum (La) and cerium (Ce) from a bastnasite ore by direct acidic leaching was investigated. The effects of acid concentration and leaching temperature on the extraction of La and Ce from the ore were tested. Using nitric (NHO3 ), more than 85% of the La and Ce were simultaneously extracted into leach solution whereas the La and Ce dissolutions were determined as less than 85% by using sulfuric acid (H2 SO4 ). The La dissolution exceeded 90% by using hydrochloric acid (HCl); however, the Ce dissolution remained below 85% under the following conditions: solid-to-liquid ratio of 20% (w/v), the acid concentration of 20%, leaching temperature of 25 °C and leaching time of 1 h. The result revealed that HNO3 could be used as a solvent for the maximum simultaneous extraction of the La and Ce from the bastnasite ore. The leaching temperature had no crucial effect on the dissolution of La and Ce when HNO3 or HCl solutions were preferred as a solvating agent. However, the leaching temperature had a slight positive effect on the dissolutions of La and Ce when H2 SO4 was used as a solvent.Öğe New voltammetric strategy for determination and electrochemical behaviors of oxaliplatin by CPT-BDD electrode(Indian Chemical Society, 2020) Aslan, Mehmet; Levent, AbdulkadirVarious drugs made of metal compounds have been used in many diseases including cancer[1]. Studies on Oxaliplatin in the literature are these [2-6]. Oxaliplatin (OxPt), which is a platinum analogue with anti-cancer effect, was accentuated. OxPt is separated from cisplatin, one of analogues of platinum, by replacing 1,2-diaminocyclohexane with amine groups. In this study, a simple, fast and sensitive voltammetric method was developed for OxPt which shows anticancer effects with cytotoxic properties. The boron-doped diamond (BDD) electrode was activated electrochemically in cathodic direction in 0.5 M H2SO4 medium. Electrochemical properties of OxPt were investigated on BDD electrode surface using square-wave and cyclic voltammetry techniques. OxPt in Britton-Robinson(BR) buffer (pH 5.0) gave a well-determined voltammetric response at +1.01 V (vs. Ag/AgCl) using the square-wave voltammetry technique. The developed voltammetric technique was found to be linear with the concentration range of 1.0-3.5 μM in the BR (pH 5.0) medium and the limit of detection was 0.276 μM (0.109 μg mL-1 ). Recommended method was successfully applied to drug forms of OxPt.
