Stability Indicating Electrochemical Methods for the Determination of Meclophenoxate Hydrochloride and Pyritinol Dihydrochloride Using Ion-Selective Membrane Electrodes

Abstract

The construction and electrochemical response characteristics of polyvinyl chloride (PVC) membrane sensors for the determination of meclophenoxate hydrochloride (I) and pyritinol dihydrochloride (II) in presence of their degradation products are described. The sensors are based on the use of the ion-association complexes of (I) and (II) cation with sodium tetraphenyl borate and ammonium reineckate counteranions as ion-exchange sites in the PVC matrix. In addition b-cyclodextrin (b-CD) membranes were used in the determination of I and II. These ion pairs and b-CD were then incorporated as electroactive species with ortho nitrophenyl octyl ether (oNPOE) as a plasticizer. Three PVC sensors were fabricated for each drug, i.e. meclophenoxate tetraphenyl borate (meclo-TPB), meclophenoxate reineckate (meclo-RNC) and meclophenoxate b-cyclodextrin (meclo-b-CD), and the same was done for pyritinol (pyrit-TPB), (pyrit-RNC) and (pyrit-b-CD). They showed near Nernestian responses for meclophenoxate over the concentration range 10 -5 -10 -2 with slopes of 52.73, 51.64 and 54.05 per concentration decade with average recoveries of 99.92± 1.077, 99.96±0.502 and 100.03±0.763 for meclo-TPB, meclo-RNC and meclo-b-CD respectively. Pyritinol also showed near Nernestian responses over the concentration range of 3.162×10 -6 -3.162×10 -4 for pyrit-TPB and pyrit-RNC, and 10 -6 -3.162×10 -4 for pyrit-b-CD with slopes of 30.60, 31.10 and 32.89 per concentration decade and average recoveries of 99.99±0.827, 100.00±0.775 and 99.99±0.680 for pyrit-TPB, pyrit-RNC and pyrit-b-CD respectively. The sensors were used successfully for the determination of I and II in laboratory prepared mixtures with their degradation products, in pharmaceutical dosage forms and in plasma.

Highly sensitive voltamperometric determination of pyritinol using carbon nanofiber/gold nanoparticle composite screen-printed carbon electrode

“…However, at present and to the best of our knowledge, only few studies related to detection of pyritinol by electrochemical methods based on polarographic, 35,36 potentiometric 37 and conductometric 38 methods are reported. To the best of our knowledge, this paper is the first study related to the detection of pyritinol by means of voltamperometric sensors.…”

“…The analytical performance characteristics are superior to those reported for ion-selective membrane electrodes. 37 This fact could be related to different detection principle (potentiometric vs voltamperometric) and to the usage of nanostructurate sensitive materials for the sensor reported here. At present and to our knowledge, voltamperometric sensors for detection of pyritinol are not reported in the literature.…”

Determination of Meclofenoxate Content in Meclofenoxate Hydrochloride for Injection by DSC and <sup>1</sup>H-NMR

“…However, meclofenoxate containing ester is easy to produce hydrolysis reaction, resulting in that its medicinal property becomes poor. Several different methods have been used for the determination of meclofenoxate including electrochemical method [1]- [3], proton magnetic resonance spectroscopy, capillary electrophoresis [4], resonance Rayleigh scattering method [5], and high performance liquid chromatography [6]- [8].…”

Capillary electrophoresis–electrochemiluminescent detection of N,N-dimethyl ethanolamine and its application in impurity profiling and stability investigation of meclophenoxate

“…1) and N,N-dimethyl ethanolamine (DMEA, III in Fig. 1 be dissolved just before use to avoid the degradation [30,31]. Due to the toxic nature of DMEA [32], it is necessary to control the hydrolysis of MCP to ensure the medication safety.…”

“…Furthermore, as a volatile compound with low vapor pressure (0.5 mm Hg at 20 • C), DMEA tends to evaporate at room temperature and is not fit to be treated with TLC until derivation is performed to improve its boiling point [30,31]. Therefore, GC methods using MS [33][34][35] and thermoconductivity [36] detectors seem to be more effective for this compound.…”