Electroanalytical investigation of antineoplastic drug vinorelbine at pencil graphite electrode in surfactant media
CitationÖnal, G., Şentürk, Z., Levent, A. (2019). Electroanalytical investigation of antineoplastic drug vinorelbine at pencil graphite electrode in surfactant media. XX. Euroanalysis Conference, 1-5 September 2019, İstanbul.
Vinorelbine (sold under the brand name Navelbine), one of the semisynthetic derivatives of Vinca alkaloids, has been widely used either alone or in combination with other drugs in the tre- atment of leukemia, lymphoma, advanced testicular cancer and Kaposi's sarcoma. From the electrochemical point of view, only one study that was quite old has been reported on its voltammetric characteris- tics so far (Brett et al.). Keeping the above knowledge in mind, in the present study, a novel application of single-use pencil graphite (PG) electrode is introduced for the determination of Vinorelbine. The electrochemical oxidation of this compound was first investigated by cyclic voltammetry in aqueous solutions. Special attention was given to the use of adsorptive stripping vol- tammetry 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 without and with the addition of different charged surfactants. The sensitivity of the stripping voltammet- ric measurements was significantly improved when the anionic (sodium dodecylsulfate, SDS) and cationic (tetra-n-butylammo- nium bromide, TBAB) surfactants were present in the Vinorelbi- ne-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 mL1−). The proposed method was successfully applied to pharmaceutical formulations and the spiked human urine samples.