Molecular Properties and Evaluation of Indion 234–Ondansetron Resinates

Ondansetron is a serotonin 5HT3 antagonist; anti-emetic drug. Bitter taste of the ondansetron is a major problem in ensuring patient compliance. The study was designed to formulate tasteless complexes of ondansetron with ion exchange resin and evaluate molecular properties of drug complex. The drug-loading process was carried out using various resins and was optimized using different drug:resin ratio and pH. Resinates were characterized by infrared spectroscopy, thermal analysis, and X-ray powder diffraction (XRPD). Indion 234 gave the best loading efficiency at drug resin ratio of 1:1.5. pH had no effect on drug loading. XRPD studies revealed that drug is in amorphous state in complex. The Infrared studies revealed complexation of secondary amine group of drug with carboxylic functional group of resin. Taste evaluation by using semiquantitative method found resonates as tasteless and agreeable. The release of drug from resinates in simulated gastric fluid was complete in 30 min. Thus, ion exchange resinates offer an effective tool for masking of bitterness and improve drug release.