Electroanalytic Investigation of Some Drugs Used in Cancer Chemotherapy by Voltammetric Method
Abstract
Vinka alkaloitleri, 40 yıldan fazla bir süredir kanser tedavisinde kullanılmaktadır. Bu çalışmada, Vinka alkaloitlerinin yarı-sentetik türevlerinden biri olan Vinorelbin tayini için tekkullanımlık kalem-ucu grafit (PG) elektrotunun yeni bir uygulaması sunulmuştur. Vinorelbin′in elektrokimyasal yükseltgenmesi ilk olarak bu elektrot kullanılarak sulu çözeltiler içerisinde dönüşümlü voltametri tekniği ile incelenmiştir. Özel ilgi ise, geniş bir pH aralığında (2.0-12.0) sürfaktansız ve sürfaktan içeren sulu çözeltilerde PG ve camımsı karbon (GC) (kıyas amaçlı) elektrotlarının yüzeyinde adsorptif sıyırma voltametrisinin kullanılmasına gösterilmiştir. PG elektrotunun kullanıldığı sıyırma voltametrisi ölçümlerinin duyarlılığı, Vinorelbin içeren elektrolit çözeltilerine pH 2.0-4.0 ve pH 9.0-10.0 ortamında sırasıyla anyonik (sodyum dodesilsülfat, SDS) ve katyonik (tetra-n-bütilamonyum bromür, TBAB) sürfaktan eklendiğinde önemli ölçüde artmıştır. Kare-dalga sıyırma voltametrisi tekniği kullanılarak 3×10-3 M TBAB içeren Britton Robinson tamponu (pH 10.0) içerisinde Vinorelbin, +0.75 V (vs. Ag/AgCl) gerilim değerinde (0.0 V′da 120 s ön-deriştirme sonrası) iyi belirlenmiş voltametrik bir yanıt vermiştir. Bu işlem, gözlenebilirlik sınırı 7.5×10-9 M (baz-5.8 ng mL-1) olan 2.3×10-8 – 5.8×10-6 M derişim aralığında bileşiğin tayini için kullanılmıştır. Önerilen yöntem, ilaç şekillerine ve Vinorelbin-ekli (spike) insan idrar örneklerine başarıyla uygulanmıştır.
Vinca alkaloids have been used in the treatment of human cancers for more than 40 years. In this study, a novel application of single-use pencil graphite (PG) electrode is introduced for the determination of Vinorelbine, one of the semisynthetic derivatives of Vinca alkaloids. The electrochemical oxidation of Vinorelbine was first investigated by cyclic voltammetry using this electrode in aqueous solutions. Special attention was given to the use of adsorptive stripping voltammetry at a surface of PG electrode and glassy carbon (GC) one (for comparison purpose) in aqueous solutions over the pH range of 2.0-12.0 both with and without the addition of surfactants. The sensitivity of the stripping voltammetric measurements was significantly improved when the anionic (sodium dodecylsulfate, SDS) and cationic (tetra-n-butylammonium bromide, TBAB) surfactants were present in the Vinorelbine-containing electrolyte solution at pH 2.0-4.0 and pH 9.0-10.0, respectively, by using PG electrode. Using square-wave stripping mode, Vinorelbine yielded a well-defined voltammetric response in Britton-Robinson buffer pH 10.0 containing 3×10-3 M TBAB at +0.75 V (vs. Ag/AgCl) (after 120 s accumulation at +0.0 V). The process could be used to determine this compound in the concentration range of 2.3×10-8 – 5.8×10-6 M, with a detection limit of 7.5×10-9 M (base-5.8 ng mL-1). The proposed method was successfully applied to pharmaceutical formulations and the spiked human urine samples.
Vinca alkaloids have been used in the treatment of human cancers for more than 40 years. In this study, a novel application of single-use pencil graphite (PG) electrode is introduced for the determination of Vinorelbine, one of the semisynthetic derivatives of Vinca alkaloids. The electrochemical oxidation of Vinorelbine was first investigated by cyclic voltammetry using this electrode in aqueous solutions. Special attention was given to the use of adsorptive stripping voltammetry at a surface of PG electrode and glassy carbon (GC) one (for comparison purpose) in aqueous solutions over the pH range of 2.0-12.0 both with and without the addition of surfactants. The sensitivity of the stripping voltammetric measurements was significantly improved when the anionic (sodium dodecylsulfate, SDS) and cationic (tetra-n-butylammonium bromide, TBAB) surfactants were present in the Vinorelbine-containing electrolyte solution at pH 2.0-4.0 and pH 9.0-10.0, respectively, by using PG electrode. Using square-wave stripping mode, Vinorelbine yielded a well-defined voltammetric response in Britton-Robinson buffer pH 10.0 containing 3×10-3 M TBAB at +0.75 V (vs. Ag/AgCl) (after 120 s accumulation at +0.0 V). The process could be used to determine this compound in the concentration range of 2.3×10-8 – 5.8×10-6 M, with a detection limit of 7.5×10-9 M (base-5.8 ng mL-1). The proposed method was successfully applied to pharmaceutical formulations and the spiked human urine samples.
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Kimya, Chemistry
Turkish CoHE Thesis Center URL
WoS Q
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