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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 Bor katkılı elmas elektrot ile naftalin’in voltametrik davranışı: Kare dalga anodik sıyırma voltametrisi ile miktar tayini(Süleyman Demirel Üniversitesi, 2017-04-28) Levent, AbdulkadirBu çalışmada, Naftalin bor katkılı elmas elektrot yüzeyindeki elektrokimyasal özellikleri, değişik çözelti ortamları ve geniş bir pH aralığında incelenmiştir. İlk olarak çalışma elektrotun performansını etkileyen değişkenler (destek elektrolitinin seçimi, elektrot temizleme yöntemi, iyon şiddeti ve pH, biriktirme/ölçüm çözeltisinin bileşimi, biriktirme gerilimi/süresi, voltametrik dalga formu değişkenleri); voltametri ve/ya da sıyırma voltametrisi teknikleri kullanılarak ayrıntılı olarak araştırılmıştır. Daha sonra önerilen yöntemlerin elde edilen optimum koşullarda Naftalin için doğrusallık (0.9-4.5 µM), saptama sınırı (LOD; 0.225 µM) ve kesinlik (% BSS 2.26) açısından validasyonu gerçekleştirilmiştir. Geliştirilen KD-ASV yöntemi, çeşme suyunda naftalinin analizi için standart katma yöntemi kullanılarak başarılı bir şekilde uygulanmıştır.Öğe Electroanalytical determination of progesterone hormone using borondoped diamond electrode(ICNTC, 2020) Levent, Abdulkadir; Uçar, MuhlisProgesterone is synthesized from pregnenolone, a derivative of cholesterol like other steroids. It is a steroid hormone that has a vital importance in human and animal health. In case of progesterone imbalance, it causes problems such as fertility and infertility. In this study, electrochemical properties of Progesterone hormone Boron doped diamond (BDD) on electrode surface were investigated in strongly acidic environment (HClO4 and H2SO4). A fast, sensitive, selective and simple electroanalytical method was developed for cathodically pre-treated BDD electrodes. A good linear analytical curve in the concentration range of 10 μM to 100 μM at a voltage value of +1.51 V (vs. Ag / AgCl) (after 120 s deposition at +0.1 V voltage) in 0.5 M HClO4 using the square wave stripping technique for the quantification of progesterone hormone obtained. The observability limit is 0.012 µM(3.77 µg L-1); The relative standard deviation value (RSD) for the concentration of 3.1 µM (n = 11) was calculated to be 4.87%. In addition, the developed voltammetric method has been successfully applied to drug and blood serum.Öğe New voltammetric strategy for determination and electrochemical behaviors of metformin by pencil graphite electrode(ICNTC, 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 Kurşun kalem elektrot ile etoposide’nin elektrokimyasal özelliklerinin incelenmesi ve miktar tayini(Batman Üniversitesi Lisansüstü Eğitim Enstitüsü, 2022-07-22) Atay, Büşra; Levent, AbdulkadirBu tez çalışmasında, bitkisel kaynaklı ve antineoplastik bir ajan olan, antikanser etki gösteren eto-posid için basit, hızlı ve duyarlı bir voltametrik yöntem geliştirilmiştir. Etoposid’in elektrokimyasal özellikleri ve miktar tayini tek kullanımlık kurşun kalem elektrot (PGE) kullanılarak kare dalga (SW) ve dönüşümlü voltametri (CV) yöntemlerinden yararlanılarak incelenmiştir. SW voltametri yöntemi ile Britton Robinson (BR) tamponu (5 mM SDS içeren pH =3.0) ortamında Etoposid’in +0.563 V (vs. Ag/AgCl) geriliminde (0.00 V ve 60 s ön-deriştirme sonrası) anlamlı voltametrik bir yanıt vermiştir. PG elektrot kullanılarak geliştirilen elektroanalitik yöntem idrar ve ilaç numunelerine başarılı bir şekilde uygulanmıştır.Öğe Kalem grafit elektrot kullanılarak edoksaban etken maddesinin elektrokimyasal davranışları ve miktar tayini için voltametrik yöntem uygulaması(Batman Üniversitesi Lisansüstü Eğitim Enstitüsü, 2022-09-13) Kılıç, Abdulkadir; Levent, AbdulkadirBu tez çalışmasında, kan sulandırıcı etki gösteren Edoksaban etken maddesinin BR (pH 9.0) çözelti ortamında kalem grafit elektrot kullanarak kare dalga ve dönüşümlü voltametri teknikleri ile elektrokimyasal özelikleri araştırılmıştır. Edoksaban’nın dönüşümlü voltametri ile alınan ölçümlerinde yaklaşık olarak +0.97 V’ ta iyi tanımlanmış tersinmez bir yanıt vermiştir. Karakterize edilen cihaz parametreleriyle BR (pH 9.0) ortamında 0.2 µM-1.8 µM aralığında doğrusal bir çalışma aralığı sunduğu ve LOD, LOQ sırsıyla değerleri 0.073 μM (0.133 μg mL-1 ) ve 0.243 μM (0.443 μg mL-1 ) olarak saptanmıştır. Tez çalışmasında geliştirilen voltametrik tekniğin uygulama sonuçları UV/Vis tekniği sonuçları ile kıyaslanmış ve birbirlerine göre uyumlu oldukları tespit edilmiştir.Öğe Kurşun kalem elektrot ile podofilotoksin′in elektroanalitik özelliklerinin incelenmesi ve miktar tayini(Batman Üniversitesi Fen Bilimleri Enstitüsü, 2019-11-19) Özer, Mehmet; Levent, AbdulkadirBu tez kapsamında antineoplastik ilaçlar içinde yer alan bitkisel kaynaklı podofilotoksin kanser (meme kanseri, prostat kanseri, kolon kanseri, küçük hücreli akciğer kanseri, lenfomalar, ve genital tümörler) ve siğil tedavilerinde kullanılmaktadır. Podofilotoksin’in miktar tayini için tek kullanımlık olan kalem grafit elektrot (PGE) kullanılarak hassas, duyarlı ve basit bir voltametrik yöntem geliştirilmiştir. Podofilotoksin’in elektrokimyasal özellikleri PG elektrot kullanılarak kare-dalga (SW) ve dönüşümlü voltametri (CV) tekniğiyle incelenmiştir. SW voltametri tekniği kullanılarak Britton Robinson (BR) tamponunda (pH 4.0) içerisinde, podofilotoksin’in +1.242 V (vs. Ag/AgCI) gerilim değerinde (0.0 V’da ve 60 s ön-deriştirme sonrası) çok iyi voltametrik bir yanıt vermiştir. Bu işlem, gözlenebilirlik sınırı 2.55 nM (1.06 µg/L) olan 1.24x10-8 – 29.4x10-8 M (12.4-299.5 nM) derişim aralığında bileşiğin miktar tayini için kullanılmıştır. Önerilen yöntem, insan idrar örneklerinde başarılı bir şekilde uygulanmıştır.Öğe Application of bismuth film electrode in determination of Loratadine by cathodic stripping voltammetry in the presence of cationic surfactant(ICNTC, 2020) Önal, Günay; Altunkaynak, Yalçın; Levent, AbdulkadirLoratadine, histamine - H1 antihistamine receptors it is being used for many years in the treatment of an allergic condition illustrating the effects on[1]. When the literature is reviewed, there are limited number of studies on Loratadine based on electrochemistry [2-5]. Stripping voltammetry is a very sensitive and selective method for determining drugs and organic / inorganic substances in biological fluids. The electrochemical behavior of Loratadine with BiFE in different supporting electrolyte and pH values, and its performance characteristics in electroanalytical determinations were investigated by cyclic voltammetry and linear sweep cathodic stripping voltammetry (LS-CSV) methods. LS-CSV measurements on the BiFE surface of 6.5x10-4 M Loratadine in 0.04 M BR buffer (pH 7.0) and 4 mM cationic surfactant (CTAB) were taken between 0.0 V and -2.0 V. Loratadine gave a voltammetric response about at -1.486 V. The limit of detection was found LOD = 1.2x10-7 M* at the BIFE surface at liner concentration range [1.305x10-6 M – 14.3x10-6 M, r = 0,998* (n = 11)]. This voltammetric method, developed under optimum conditions, has been successfully applied to pharmaceutical formulations of Loratadin as fast, easy to apply, sensitive and environmentally friendly.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.Öğe New voltammetric method for determination and electrochemical behaviors of oxaliplatin by CPT-BDD electrode(ICNTC, 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.
