ethyl-cellulose and glyceryl-behenate

In this study, once-daily, sustained-release matrix tablets of tolterodine l-tartrate (TOL) for treatment of overactive bladder (OAB) were prepared by direct compression using various amounts of hydrophilic polymers such as HPMC 2910 and HPMC 2208 along with other tablet excipients; the tablets were then coated. In vitro dissolution studies were carried out under different pH conditions. The dissolution data were fitted into zero-order, first-order, Higuchi and Korsemeyer-Peppas models to identify the pharmacokinetics and mechanism of drug release. Among the four formulations (F1-F4), the dissolution profiles of formulation F2 were most similar to the marketed product with similarity and difference factors of 70.25 and 1.59 respectively. Furthermore, pharmacokinetic studies were carried out in healthy human volunteers after oral administration of the prepared TOL sustained-release matrix-coated tablet and the marketed product. The results revealed that the pharmacokinetic parameters of AUC, Cmax, Tmax, t1/2, Kel, and MRT of TOL for the developed formulation (F2) were not significantly different from that for the marketed product, suggesting that they were bioequivalent. Therefore, the developed sustained-release tablet formulation of TOL could be an alternative dosage form to the SR capsule for treatment of OAB.

Topics: Benzhydryl Compounds; Cellulose; Cresols; Cross-Over Studies; Delayed-Action Preparations; Drug Administration Schedule; Drug Compounding; Excipients; Fatty Acids; Hardness; Humans; Hypromellose Derivatives; Methylcellulose; Phenylpropanolamine; Solubility; Tablets; Therapeutic Equivalency; Tolterodine Tartrate; Urological Agents

The objective was to develop eperisone HCl sustained-release pellets through extrusion spheronization technique and to determine the influence of different hydrophobic (polymeric based and wax-based) and hydrophilic (polymeric based) matrix former on the release of eperisone HCl (BCS class I drug) and on pellet sphericity. The pellet formulations consisted of different hydrophobic and hydrophilic matrix formers like HPMC K4M (10-20%) HPMC K15M (10%), EC (7cps) (10-20%), Carnauba wax (10-20%), Compritol ATO 888 (10-20%), Glyceryl monostearate (10%), lactose and microcrystalline cellulose. The initial burst release of the drug from matrix pellet formulations was effectively controlled by coating with 5% EC (ethylcellulose) dispersion. The dissolution profile and drug release kinetics of coated pellet formulations were determined at both acidic and basic pH medium. SEM (Scanning electron microscope) technique was used to determine the surface morphology and cross-section of F5 and F7 pellet formulation. The mechanism of drug release of coated formulation followed non-Fickian diffusion. FTIR spectroscopy was conducted and no drug and excipients interaction was observed. The results had shown that optimized coated formulation was F5 and F7 which effectively extend the drug release for 12 hours.

Topics: Cellulose; Chemistry, Pharmaceutical; Delayed-Action Preparations; Drug Development; Drug Liberation; Excipients; Fatty Acids; Glycerides; Lactose; Methylcellulose; Microscopy, Electron, Scanning; Muscle Relaxants, Central; Polymers; Propiophenones; Spectroscopy, Fourier Transform Infrared; Waxes

Even though ion-exchange resins are good drug carriers to get sustained release properties, it may not be good enough only with themselves. For further sustained release effect, a diffusion barrier or coating on the resins' surface can be utilized. Initially, microencapsulation using a w/o/w double emulsion method was used to apply ethylcellulose (EC) onto the drug/resin complexes. Typical pharmaceutical waxes can be alternative materials to delay the drug release from the complex. After the coating, the coated resin particles were incorporated into fast-disintegrating tablets to get an idea regarding the effects of wet granulation and compression on the release. Among the different grades of ECs tested (Ethocel 20, 45, and 100), more viscous EC resulted in better morphologies and sustained release effects. Because the drug release rate was significantly dependent on the coating level, the release rate can be modified easily by changing different levels of the coating. The drug release rate was also strongly dependent on the granulation and compaction process as the coated particles were incorporated into the tablet dosage form. Among the tested waxes, stearic acid had an effect on the sustained release together with lubrication and wetting properties. Even though microencapsulation or wax coating may not be practical for real manufacturing, the results may give valuable information how to formulate sustained release dosage forms and their properties on the tablet preparation.

Topics: Algorithms; Cellulose; Chemistry, Pharmaceutical; Delayed-Action Preparations; Diffusion; Drug Carriers; Drug Compounding; Emulsions; Fatty Acids; Ion Exchange Resins; Microscopy, Electron, Scanning; Powders; Resins, Synthetic; Solubility; Solvents; Stearic Acids; Tablets; Waxes

The present research was directed towards fabrication of modified-release captopril oral formulation. A 3(2) full factorial design was employed for optimization using captopril to Compritol ATO 888 ratio (X1) and extragranular fraction of ethyl cellulose (X2) as independent variables. The percentage drug released in 1 h (Y1) and the time required to release 80% of the drug (Y2) were selected as dependent variables. Eutectic blend of camphor and menthol was used as a solvent to facilitate the drug distribution in matrix. The optimized batch containing 50 mg captopril, 160 mg Compritol ATO 888 and 220 mg ethyl cellulose was formulated by overlapping the contour plots of Y1 and Y2. The responses Y1 and Y2 of optimized batch were 25% and 520 min, respectively. The kinetics of drug release was best explained by Korsmeyer-Peppas model. The results of artificial neural network were superior in prediction power than the factorial design for both the responses (Y1 and Y2).

Topics: Administration, Oral; Algorithms; Analysis of Variance; Biological Availability; Camphor; Captopril; Cellulose; Chemistry, Pharmaceutical; Delayed-Action Preparations; Drug Stability; Excipients; Fatty Acids; Humans; Kinetics; Menthol; Models, Biological; Models, Statistical; Neural Networks, Computer; Regression Analysis; Spectroscopy, Fourier Transform Infrared