Nebivolol, a cardioselective β-blocker undergoes extensive metabolism in the liver after its oral administration resulting in low bioavailability. Oral administration of nebivolol also causes gastrointestinal disturbances characterised by stomach ache. To overcome these short comings, mucoadhesive buccal films of nebivolol were prepared using different concentrations of hydroxypropyl methylcell...

The deformation mechanism of pharmaceutical powders, used in formulating directly compressed matrix tablets, affects the characteristics of the formed tablets. Three polymers of different deformation mechanisms were tested for their impact on theophylline directly compressed tablets namely Kollidon SR (KL SR, plastic deformation), Ethylcellulose (EC, elastic deformation) and Carnauba wax (CW, b...

In previous publications from this laboratory we suggested the use of radioprotective drugs in a sustained-release form as a practical way to cope with their high toxicity and quick metabolism and excretion. Cysteine and cysteamine, well-established radioprotectants, were used as model drugs and compressed at various concentrations (0-65%) into an insoluble tablet matrix, composed of ethylcellu...

Simple ketoprofen microspheres (MS) were prepared by the dry-in-oil method using ethylcellulose (EC) as a matrix polymer. Further, the microspheres modified by addition of polyethylene glycol (PEG) and hydroxypropyl cellulose (HPC), called MS-P and MS-H, respectively, were prepared. The in vitro release from MS, MS-P and MS-H was examined in the JP XIII second fluid, pH 6.8, at 37 degrees C and...

In this study calendering is used as a downstream technique to shape monolithic co-extruded fixed-dose combination products in a continuous way. Co-extrudates with a metoprolol tartrate-loaded sustained-release core and a hydrochlorothiazide-loaded immediate-release coat were produced and immediately shaped into a monolithic drug delivery system via calendering, using chilled rolls with tablet-...

Purpose: To prepare and evaluate metformin microspheres for prolonged release. Methods: Metformin microspheres were prepared by non-aqueous solvent evaporation method using various polymers, including ethylcellulose (EC), hydroxypropyl methylcellulose (HPMC), carbopol 934P (CA) and chitosan (CH). The effect of process variables, viz, drug/polymer ratio, stirring rate and type of polymer on the ...

A Multilayered Multidisk Tablet (MLMDT) comprising two drug-loaded disks enveloped by three drug-free barrier layers was developed for use in chronotherapeutic disorders, employing two model drugs, theophylline and diltiazem HCl. The MLMDT was designed to achieve two pulses of drug release separated by a lag phase. The polymer disk comprised hydroxyethylcellulose (HEC) and ethylcellulose (EC) g...

Purpose: To develop and optimize controlled-release (CR) oxybutynin chloride matrix tablets. Methods: Oxybutynin CR tablets were prepared by embedding drug-containing granules into a hydrogel matrix of hydroxypropyl methylcellulose (HPMC). A coating layer was then applied with a mixture of HPMC, ethylcellulose, shellac, and HPMC phthalate. The effect of several formulation variables on in vitro...

_____________________________________________________________________________ Abstract The objective of this study was to evaluate the effects of slow-release α-amylase in ruminal in vitro digestion of maize and sorghum grains. Digestibility was measured using an in vitro procedure with 40 mL of buffer and 10 mL of ruminal fluid, flushed with CO2 and incubated at 39 °C. The digestibility of sor...

Purpose: The objective of this study was to formulate and evaluate a matrix microsphere system for simultaneous delivery of two anti-asthmatic drugs Salbutamol sulphate and Theophylline which are often indicated for the management of asthma, their frequent dosing may reduce compliance, thus making a prolonged release formulation necessary. Ethylcellulose was used as a retardant polymer and its ...