First derivative spectrophotometric determination of granisetron hydrochloride in presence of its hydrolytic products and preservative and application to pharmaceutical preparations

Economical Voltammetric Sensor for Sensitive Rapid Determination of Ondansetron in the Presence of Opioid Antagonist Naltrexone

The electrochemical actions of ondansetron (OND) were investigated on the modified electrode with Polyvinyl Pyrollidone (PVP) and multi-walled carbon nanotube (MWCNTs). The oxidation peak current was enhanced to be doubled when compared to the bare electrode as a result of the synergistic effect of nanomaterial and cation-exchange polymer on the electron transfer rate. Following optimization of the experimental conditions, the Square Wave Voltammograms (SWV) method was employed to determine ondansetron in pharmaceutical formulations. Moreover, the modified electrode MWCNTs/PVP/CPE displayed high selectivity in the voltammetric measurements of ondansetron and co-administrated opioid antagonist drug naltrexone (NAL) with strong potential separation (422 mV). The response peak currents had a linear relationship with drug concentration in the range of (2.00–200.0 nmolL−1) with detection limits 430 pmolL−1 and 456 pmolL−1 for ondansetron and naltrexone, respectively. The electrode was successfully used to detect both medications electrochemically in human plasma samples.

Graphical abstract

Simultaneous Determination of Co-administrated Deflazacort, Aprepitant and Granisetron in Dosage Forms and Spiked Human Plasma by RP-HPLC/PAD

A selective reversed phase high performance liquid chromatography/photodiode array detector (RP-HPLC/PAD) method has been developed for simultaneous determination of the three co-administrated deflazacort, aprepitant and granisetron drugs used with chemotherapy. The three cited drugs have been chromatographed on C18 column using a mobile phase consisting of acetonitrile–0.2% v/v triethylamine (80:20 v/v, pH of 6.6 ± 0.05) with isocratic elution and monitored by photodiode array at 220 nm. International conference on harmonization (ICH) guidelines were followed to validate the developed method. Successful application of the developed method was assessed by the simultaneous determination of the studied drugs in pure forms, dosage forms and plasma samples in the ranges of 0.2–20, 0.4–40 and 0.2–20 μg/mL for deflazacort, aprepitant and granisetron, respectively.

In situ polymerization and FT-IR characterization of poly-glycine on pencil graphite electrode for sensitive determination of anti-emetic drug, granisetron in injections and human plasma

In situ polymerization is a simple and efficient technique for modification and fabrication of modified electrodes in voltammetry. An efficient and highly sensitive square wave voltammetric (SWV) method was developed for analysis of a 5-HT₃ antagonist granisetron (GRN) using in situ polymerized glycine on pencil graphite electrode surface. It was found that the fabricated polymer enhanced the sensitivity by more than two times and enhanced the surface activity by more than three times. Surface area measurements showed that poly-Gly/PGE have large surface area of 44.3 mm², when compared to that of bare PEG (12.1 mm²). Several methods as cyclic voltammetry (CV), electrochemical impedance spectroscopy (EIS) and scanning electron microscopy (SEM) techniques were used to characterize the modified surface. Further, FT-IR spectroscopic study was used to predict the way of glycine polymerization on electrode surface and the possible interaction mechanism with GRN. After optimization, the proposed method showed a linear response of GRN concentrations in the range from 0.08 to 3.00 μmol L⁻¹ with a limit of detection (LOD) of 26.2 nmol L⁻¹ (9.14 ng mL⁻¹). The method was utilized for GRN determination in ampoules and in real human plasma samples.

In situ polymerization is a simple and efficient technique for modification and fabrication of modified electrodes in voltammetry.