Incorporation of calcium salts into xanthan gum matrices: hydration, erosion and drug release characteristics

Abstract

Xanthan gum, a hydrophilic biopolymer with modified release properties, was used to produce directly compressed matrix tablets containing a model drug, Sodium paminosalicylate. Three formulations were prepared, each containing a different calcium dihydrate salt: Calcium Chloride, Calcium Sulfate or Dibasic Calcium Phosphate. The aim of the investigation was to relate the calcium ion content and solubility of the calcium salt to the in vitro drug release profile of the xanthan matrices. Tablet hydration, erosion and drug release were determined in distilled water using the BP paddle method. The data showed that the overall drug release was the greatest with addition of calcium Sulfate, followed by Calcium Chloride and dibasic Calcium Phosphate. The chloride salt formulation displayed the greatest percentage erosion due to rapid mass loss during the initial phase, followed by those with sulfate or phosphate salts. As xanthan gel viscosity increased and drug release was also found to be lower. It can be concluded that drug release is influenced by the solubility of the salt present in the formulation, since these parameters determine the viscosity and structure of the gel layer.

Mixed solvent system as binder for the production of silicified microcrystalline cellulose‐based pellets

“…35 This was because hydration of MCC differs from HPMC. 38 As expected with our pellets, applying low viscosity grade HPMC produces gel with less resistance to mechanical 35 At the end of 8th hour, D1 and D2 gave approximately 55 and 90% drug release, respectively.…”

“…The diffusional exponent (n) values for D1 and D2 based on KS model were 0.65 and 0.86, respectively, indicated a non-Fickian or anomalous transport (0.45 < n < 0.89) for the drug release mechanism. 38 As expected with our pellets, applying low viscosity grade HPMC produces gel with less resistance to mechanical…”

“…A study has shown that there were immediate and steady drug release for MCC-and HPMC-based tablets, respectively. 38 From our analysis, D1 is best described with Higuchi model (R 2 = 0.9966), while D2 adhered best to Kosmeyer-Peppas (KS) model (R 2 = 0.9915). Water molecules were trapped within the MCC sponge to induce local swelling of matrix 36 meanwhile a regular hydration was seen in Methocel E15LV granules as fully amorphous HPMC allowed greater water mobility to occur than MCC.…”

“…37 The pellet dissolution profiles were further analyzed for the best fitted kinetic models. 38 From our analysis, D1 is best described with Higuchi model (R 2 = 0.9966), while D2 adhered best to Kosmeyer-Peppas (KS) model (R 2 = 0.9915). However D1 also fitted to KS model (R 2 = 0.9922).…”

Attenuation of Intestinal Efflux Pump thru Polymers and Preservatives

“…XG has been used in combination with other polymers to increase viscosity of the solutions. Cross linking structure of xanthan controls the release of drugs and it exhibits a near zero order drug release [17]. Tragacanth gum which is a biodegradable and biocompatible polymer that is used as an emulsifying agent, rheology enhancer, etc.…”