Highly sensitive ion-exchanger based polyvinyl chloride membrane sensor for determination of vinpocetine and its use in drugs analysis
Abstract
It has been established that the correct choice of the ion-exchanger, plasticiser and the measurement conditions makes it possible to achieve analytical characteristics of vinpocetine-sensitive electrodes based on commercially available components, far superior to those described in the literature. It has been found, that the effect of pH on the vinpocetine-sensitive electrodes response takes place in much more acidic media than might be expected from protolytic equilibrium and is due to the extraction of the molecular form of vinpocetine into the membrane phase from both external and inner solutions. Very good parameters of selectivity (from –7.4 to – 9.8 in respect to inorganic ions), lower detection limit (1.7 ⋅ 10–7 mol ⋅ L–1), linear response range (1.0 ⋅ 10– 6 mol ⋅ L–1), and potential reproducibility (± 0.06 mV in 1.0 ⋅ 10– 4 mol ⋅ L–1 solution of vinpocetine) are achieved using 2-nitrophenyl octyl ether as a plasticiser, potassium tetrakis(4-chlorophenyl)borate as an ion-exchanger and creating conditions that exclude non-exchangable extraction of vinpocetine into the membrane at the stages of both conditioning the electrode and performing measurements. Methods for the determination of vinpocetine in dosage forms (pills and solutions for injections) using both direct potentiometry and potentiometric titration techniques characterised by simplicity, rapidity and high metrological characteristics have been proposed.
References
- Egorov VV, Nazarov VA, Andronchyk KA, Zdrachek EA. [Ion-selective electrodes application in pharmaceutical analysis]. In: Petrov PT, Romanovskii DI, Dubovik BV, editors. Belorusskie lekarstva. Materialy Mezhdunarodnoi nauchnoprakticheskoi konferentsii; 2–3 noyabrya 2010 g.; Minsk, Belarus’ [Belarusian medicines. Materials of the International scientific and practical conference; 2010 November 2–3; Minsk, Belarus]. Minsk: Institute for Pharmacology and Biochemistry of the National Academy of Sciences of Belarus; 2010. p. 10–13. Russian.
- Vytras K. Potentiometric titrations based on ion-pair formation. IonSelective Electrode Reviews.1985;7(1):77–164. DOI: 10.1016/B978-0-08-034150-7.50007-3.
- Egorov VV. Determination of cationic surface-active antiseptics by ion-selective electrodes. Journal of Analytical Chemistry. 1996;51(10):986–988.
- Kharitonov SV. Ion-selective electrodes in medicinal drug determination. Russian Chemical Reviews. 2007;76(4):361–395. DOI: 10.1070/rc2007v076n04abeh003670.
- Stefan RI, van Staden JR, Aboul-Enein HY. Electrochemical sensors in bioanalysis. New York: CRC Press Inc.; 2001. 312 p.
- Cosofre VV, Buck RP. Recent advances in pharmaceutical analysis with potentiometric membrane sensors. Critical Reviews in Analytical Chemistry. 1993;24(1):1–58. DOI: 10.1080/10408349308048818.
- Gupta VK, Arunima N, Singhal B, Agarwal S. Recent advances on potentiometric membrane sensors for pharmaceutical analysis. Combinatorial Chemistry and High Throughput Screening. 2011;14(4):284–302. DOI: 10.2174/138620711795222437.
- Stefan RJ, Baiulescu GE, Aboul-Enein HY. Ion-selective membrane electrodes in pharmaceutical analysis. Critical Reviews in Analytical Chemistry. 1997;27(4):307–321. DOI: 10.1080/10408349708050589.
- Cosofret VV. Pharmaceutical applications of membrane sensors. Boca Raton: CRC Press; 1992. 443 p. DOI: 10.1201/9781351075497.
- Council of Europe. European Pharmacopoeia. 7th edition. Strasbourg: Council of Europe; 2010. 44 p.
- United States Pharmacopeia. United States Pharmacopeial Convention – 2003. Rockville: United States Pharmacopeia; 2003.
- Sheryakov VV, editor. Kontrol’ kachestva vspomogatel’nykh veshchestv i lekarstvennogo syr’ya [Quality control of excipients and medicinal raw materials]. Maladziechna: Tipografiya «Pobeda»; 2008. 472 p. (Gosudarstvennaya farmakopeya Respubliki Belarus’; volume 2).
- El-Gindy А, Emara S, Mesbah MK, Hadad GM. Spectrophotometric and liquid chromatographic determination of fenofibrate and vinpocetine and their hydrolysis products. Farmaco. 2005;60(5):425–438. DOI: 10.1016/j.farmac.2005.01.013.
- Abdelrahman MM, Abdelwahab NS, Salama FM, Ahmed AB. Different chromatographic methods for the simultaneous determination of vitamin E and vinpocetine in their combined dosage form and in the presence of the alkaline-induced degradation product of vinpocetine. Journal of Planar Chromatography. 2016;29(5):372–379. DOI: 10.1556/1006.2016.29.5.8.
- Elkady EF, Tammam MH, Mohamed AA. Development and validation of an RP-HPLC method for the determination of vinpocetine and folic acid in the presence of a vinpocetine alkaline degradation product in bulk and in capsule form. Journal of AOAC International. 2017;100(3):671–676. DOI: 10.5740/jaoacint.16-0239.
- Mazák K, Vámos J, Nemes A, Rácz A, Noszál B. Lipophilicity of vinpocetine and related compounds characterized by reversed-phase thin-layer chromatography. Journal of Chromatography A. 2003;996(1–2):195–203. DOI: 10.1016/S0021-9673(03)00617-4.
- Zhang YS, Li JD, Yan C. An update on vinpocetine: new discoveries and clinical implications. European Journal of Pharmacology. 2018;819:30–34. DOI: 10.1016/j.ejphar.2017.11.041.
- Ahmed TA. Formulation and clinical investigation of optimized vinpocetine lyoplant-tabs: new strategy in development of buccal solid dosage form. Drug Design, Development and Therapy. 2019;13:205–220. DOI: 10.2147/DDDT.S189105.
- Ding J, Li J, Mao S. Development and evaluation of vinpocetine inclusion complex for brain targeting. Asian Journal of Pharmaceutical Sciences. 2015;10(2):114–120. DOI: 10.1016/j.ajps.2014.08.008.
- Ma YH, Ge SW, Wang W, Zheng Q, Zuo YW, Zhong CJ, et al. Novel perchlorate and phosphate salts of vinpocetine: characterization, relative solid-state stability evaluation and Hirshfeld surface analysis. Journal of Molecular Structure. 2016;1105:1–10. DOI: 10.1016/j.molstruc.2015.10.029.
- Wagdy HAA, Nashar RM. Vinpocetine chemical sensor for its dissolution testing, assay and as HPLC detector. Sensor Letters. 2010;8(6):838–847.
- Lushchik YF. Nekotorye zakonomernosti funktsionirovaniya i analiticheskoe primenenie kationoselektivnykh elektrodov na osnove vysshikh sul’fokislot i ikh kompozitsii s neitral’nymi perenoschikami [Some regularities of the functioning of cation-selective electrodes based either on higher sulfonic acids or their composition with neutral carriers and their analytical application] [dissertation]. Minsk: Belorusskii ordena Trudovogo Krasnogo Znameni gosudarstvennyi universitet imeni V. I. Lenina; 1988. 206 p. Russian.
- Sokalski T, Zwickl T, Bakker E, Pretsch E. Lowering the detection limit of solvent polymeric ion-selective electrodes. 1. Modeling the influence of steady-state ion fluxes. Analytical Chemistry. 1999;71(6):1204–1209. DOI: 10.1021/ac980944v.
- Bakker E. Determination of unbiased selectivity coefficients of neutral carrier-based cation-selective electrodes. Analytical Chemistry. 1997;69(6):1061–1069. DOI: 10.1021/ac960891m.
- Egorov VV, Bolotin AA. Ion-selective electrodes for determination of organic ammonium ions: ways for selectivity control. Talanta. 2006;70(5):1107–1116. DOI: 10.1016/j.talanta.2006.02.025.
- Egorov VV, Astapovich RI, Bolotin AA, Vysotskii DL, Nazarov VA, Matulis VE, et al. The influence of the plasticizer nature on the selectivity of ion-selective electrodes to physiologically active amine cations: regularities and abnormalities. Journal of Analytical Chemistry. 2010;65:404–413. DOI: 10.1134/S1061934810040118.
- Egorov VV, Lyaskovski PL, Il’inchik IV, Soroka VV, Nazarov VA. Estimation of ion-pairing constants in plasticized poly(vinylchloride) membranes using segmented sandwich membranes technique. Electroanalysis. 2009;21(17–18):2061–2070. DOI: 10.1002/elan.200904639.
- Morf WE. The principles of ionselective electrodes and of membrane transport. Budapest: Elsevier; 1981. 433 p.
- Salih FA, Novakovskii AD, Egorov VV. Verapamil-sensitive electrodes: main factors responsible for analytical performance and use in drug analysis. Journal of Analytical Chemistry. 2022;77(12):1586–1594. DOI: 10.1134/S1061934822120127.
- Salih FA, Novakovskii AD, Egorov VV. Insight into response of ion-exchanger-based electrodes sensitive to highly lipophilic physiologically active amines. Journal of Electroanalytical Chemistry. 2022;920:116561. DOI: 10.1016/j.jelechem.2022.116561.
- Egorov VV, Novakovskii AD, Salih FA, Semenov AV, Akayeu YB. Description of the effects of non‐ion‐exchange extraction and intra‐membrane interactions on the ion‐selective electrodes response within the interface equilibria‐triggered model. Electroanalysis. 2020;32(4):674–682. DOI: 10.1002/elan.201900647.
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