Floating granules of ranitidine hydrochloride-gelucire 43/01: Formulation optimization using factorial design

The purpose of this research was to develop and optimize a controlled-release multiunit floating system of a highly water soluble drug, ranitidine HCl, using Compritol, Gelucire 50/13, and Gelucire 43/01 as lipid carriers. Ranitidine HCl-lipid granules were prepared by the melt granulation technique and evaluated for in vitro floating and drug release. ethyl cellulose, methylcellulose, and hydroxypropyl methylcellulose were evaluated as release rate modifiers. A 32 full factorial design was used for optimization by taking the amounts of Gelucire 43/01 (X1) and ethyl cellulose (X2) as independent variables, and the percentage drug released in 1(Q1), 5(Q5), and 10 (Q10) hours as dependent variables. The results revealed that the moderate amount of Gelucire 43/01 and ethyl cellulose provides desired release of ranitidine hydrochloride from a floating system. Batch F4 was considered optimum since it contained less Gelucire and was more similar to the theoretically predicted dissolution profile (f2=62.43). The temperature sensitivity studies for the prepared formulations at 40°C/75% relative humidity for 3 months showed no significant change in in vitro drug release pattern. These studies indicate that the hydrophobic lipid Gelucire 43/01 can be considered an effective carrier for design of a multiunit floating drug delivery system for highly water soluble drugs such as ranitidine HCl

Controlled-Release Carbamazepine Granules and Tablets Comprising Lipophilic and Hydrophilic Matrix Components

The objective of this study was to investigate the effect of lipophilic (Compritol® 888 ATO) and hydrophilic components (combination of HPMC and Avicel) on the release of carbamazepine from granules and corresponding tablet. Wet granulation followed by compression was employed for preparation of granules and tablets. The matrix swelling behavior was investigated. The dissolution profiles of each formulation were compared to those of Tegretol® CR tablets and the mean dissolution time (MDT), dissolution efficiency (DE %) and similarity factor (f2 factor) were calculated. It was found that increase in the concentration of HPMC results in reduction in the release rate from granules and achievement of zero-order is difficult from the granules. The amount of HPMC plays a dominant role for the drug release. The release mechanism of CBZ from matrix tablet formulations follows non-Fickian diffusion shifting to case II by the increase of HPMC content, indicating significant contribution of erosion. Increasing in drug loading resulted in acceleration of the drug release and in anomalous controlled-release mechanism due to delayed hydration of the tablets. These results suggest that wet granulation followed by compression could be a suitable method to formulate sustained release CBZ tablets

Preparation and evaluation of diltiazem hydrochloride-gelucire 43/01 floating granules prepared by melt granulation

The basic objective of this study was to explore the application of Gelucire 43/01 for the design of multi-unit floating systems of a highly water-soluble drug diltiazem HCl. Diltiazem HCl-Gelucire 43/01 granules were prepared by melt granulation technique. The granules were evaluated for in vitro and in vivo floating ability, surface topography, and in vitro drug release. Aging effect on storage was vvaluated using scanning electron microscopy, hot stage polarizing microscopy (HSPM), differential scanning calorimetry (DSC), and in vitro drug release. Granules were retained in stomach at least for 6 hours. Approximately 65% to 80% drug was released over 6 hours with initial fast release from the surface. Surface topography, HSPM, DSC study of the aged samples showed phase transformation of Gelucire. The phase transformation also caused significant increase in drug release. In conclusion, hydrophobic lipid, Gelucire 43/01, can be considered as an effective carrier for design of a multi-unit floating drug delivery system of highly water-soluble drugs such as diltiazem HCl

Preparation and characterization of etoricoxib solid dispersions using lipid carriers by spray drying technique

The basic objectives of this study were to prepare and characterize solid dispersions of poorly water-soluble drug etoricoxib using lipid carriers by spray drying technique. The properties of solid dispersions were studied by diffuse reflectance infrared Fourier transform spectroscopy (DRIFTS), differential scanning calorimetry (DSC), hotstage microscopy (HSM), radiograph powder diffraction (XRPD), and dissolution studies. The absence of etoricoxib peaks in XRPD profiles of solid dispersions suggests the transformation of crystalline etoricoxib into an amorphous form. In the HSM examination of solid dispersions, the dissolution of drug in the lipid carriers was observed, which was also confirmed by the absence of etoricoxib peak in DSC curves of solid dispersions. The DRIFTS spectra revealed the presence of hydrogen bonding in solid dispersions. The in vitro dissolution rate of solid dispersions as compared with pure etoricoxib, spray-dried etoricoxib, and physical mixtures of drug with lipid carriers. Therefore, the dissolution rate of poorly water-soluble drug etoricoxib can be significantly enhanced by the preparation of solid dispersions using lipid carriers by spray drying technique