Simultaneous Determination of Three 5-HT3Receptor Antagonists Accompanied by Stability Study Using Thin-Layer Chromatography–Densitometry

Abstract

A thin-layer chromatographic (TLC)—densitometric method for the separation and simultaneous determination of 3 5-HT3 receptor antagonists, namely, tropisetron hydrochloride (TRP), granisetron hydrochloride (GRN), and ondansetron hydrochloride dihydrate (OND) was developed. Densitometric measurements were done at 285 nm for TRP and 305 nm for both OND and GRN using the reflectance—absorbance mode. Separation was carried out on silica gel TLC plates using chloroform—methanol—ammonia (10 m) (8:2:0.1, V/V) as the mobile phase. The three drugs have been separated with RF values of 0.23 ± 0.01, 0.63 ± 0.01, and 0.76 ± 0.01 for TRP, GRN, and OND, respectively. The limits of detection and quantification for linear regression analysis of the studied drugs ranged from 2.79 to 12.05 and from 8.45 to 36.50 ng per band, respectively, while for polynomial regression, the limits of detection and quantification for the studied drugs ranged from 3.40 to 15.51 and from 10.31 to 46.99 ng per band, respectively. The developed method was applied for determination of the studied drugs in pharmaceuticals and human plasma with good precision and accuracy. Stability-indicating thin-layer chromatographic method for the determination of OND in the presence of its degradation products under different conditions and subsequent kinetic study had been successfully applied.