Effects of Weak and Strong Cation Exchange Resins on MoistureUptake Behaviorof Ranitidine Hydrochloride: Effect of resins on hygroscopicity of ranitidine

The aim of the present research was to study the effects of weak cation exchangeresins, polacrilex with exchangeable H+and polacrillin potassium and strong cationexchange resin sodium polystyrene sulfonate on water uptake behavior of ranitidinehydrochloride. Drug resin complexes (DRC) were prepared and evaluated for thepercentage of moisture gain when placed in a humidity chamber at 40E2 °C and75E5% RH for 17 h as compared to drug and free resins under the same condition.Equilibrium moisture content (EMC) under different humidity conditions and therate and extent of moisture uptake in the presence (15 watt florescence light) andabsence of light under 40E2 °C and 75E5% RH were also calculated for DRCs,drug and unloaded resins. DRC 264 (containing polacrilex with H+) gained minimumweight (10.22%) maintaining free flowing characteristics whereas other resinatesshowed higher weight gain and formation of sticky mass while ranitidine HClturned liquid with gain of 28.11% weight. The rate of moisture uptake by ranitidineHCl was found to increase in the presence of light with slight difference in extent,whereas moisture uptake rate was independent of light in the case of resins. Eventhough DRC 264 contained ranitidine HCl, the moisture uptake rate was unaffectedby light and saturation in moisture gain was seen just at 6 h. Thus, loading ranitidineHCl on polacrilex resin with exchangeable H+significantly improves its moistureresistance and may not require very tight environmental controls during itsformulation

Taste masking of ondansetron hydrochloride by polymer carrier system and formulation of rapid-disintegrating tablets

The purpose of this research was to mask the intensely bitter taste of ondansetron HCl and to formulate a rapiddisintegrating tablet (RDT) of the taste-maske drug. Taste masking was done by complexing ondansetron HCl with aminoalkyl methacrylate copolymer (Eudragit EPO) in different ratios by the precipitation method. Drug-polymer complexes (DPCs) were tested for drug content, in vitro taste in simulated salivary fluid (SSF) of pH 6.2, and molecular property. Complex that did not release drug in SSF was considered taste-masked and selected for formulation RDTs. The complex with drug-polymer ratio of 8∶2 did not show drug release in SSF; therefore, it was selected. The properties of tablets such as tensile strength, wetting time, water absorption ratio, in vitro disintegration time, and disintegration in the oral cavity were investigated to elucidate the wetting and disintegration characteristics of tablets. Polyplasdone XL-10 7% wt/wt gave the minimum disintegration time. Tablets of batch F4 containing spray-dried mannitol and microcrystalline cellulose in the ratio 1∶1 and 7% wt/wt Polyplasdone XL-10 showed faster disintegration, within 12.5 seconds, than the marketed tablet (112 seconds). Good correlation between in vitro disintegration behavior and in the oral cavity was recognized. Taste evaluation of RDT in human volunteers revealed considerable taste masking with the degree of bitterness below threshold value (0.5) ultimately reaching to 0 within 15 minutes, whereas ondansetron HCl was rated intensely bitter with a score of 3 for 10 minutes. Tablets of batch F4 also revealed rapid drug release (t90, 60 seconds) in SGF compared with marketed formulation (t90, 240 seconds;P<.01). Thus, results conclusively demonstrated successful masking of taste and rapid disintegration of the formulated tablets in the oral cavity