Eudragit(®) RS PO/RL PO as rate-controlling matrix-formers via roller compaction: Influence of formulation and process variables on functional attributes of granules and tablets.

The influence of plasticizer level, roll pressure and sintering temperature was investigated on the granule properties, tablet breaking force and theophylline release from tablets. Nine formulations using theophylline as a model drug, Eudragit(®) RL PO, Eudragit(®) RS PO, or both as a matrix former and triethyl citrate (TEC) as a plasticizer were prepared. The formulations were roller compacted and the granules obtained were evaluated for particle size distribution and flowability.

Quality by design, part III: study of curing process of sustained release coated products using NIR spectroscopy.

This study investigated the potential of near infrared spectroscopy (NIRS) to assess film coat curing for tablets coated with methacrylate copolymers. The ability of NIRS to monitor film coat curing was studied and compared to conventional methods like differential scanning calorimetry (DSC) and hot-stage microscopy (HSOM). This study showed that variation in the curing temperature and duration affected the NIR spectra for all formulations.

Quality by design, part II: application of NIR spectroscopy to monitor the coating process for a pharmaceutical sustained release product.

Ammonio methacrylate copolymers are commercially available as Eudragit RL/RS; they differ in the degree of quaternary ammonium group substitution, which gives them different permeabilities. These closely related polymers can be combined in various ratios to control release rate; consequently, release rate is controlled by the polymer composition and coating thickness. Therefore, predicting drug release from methacrylate copolymers using near infrared spectroscopy (NIRS) can be technically difficult.

Quality by design, part I: application of NIR spectroscopy to monitor tablet manufacturing process.

To monitor tableting production using near infrared (NIR) spectroscopy, chemometric models were developed to analyze peak compression force, crushing strength and content uniformity. To measure tablet content uniformity, orbifloxacin tablets with drug content ranging from 60 to 90 mg were made and analyzed using ultraviolet (UV) and NIR spectroscopy. To assess the compression force and crushing strength, several batches of tablets were made on a Stokes B2 rotary tablet press and compression force was varied from 360 to 3500 lb.

Assessment of NIR spectroscopy for nondestructive analysis of physical and chemical attributes of sulfamethazine bolus dosage forms.

The goal of this study was to assess the utility of near infrared (NIR) spectroscopy for the determination of content uniformity, tablet crushing strength (tablet hardness), and dissolution rate in sulfamethazine veterinary bolus dosage forms. A formulation containing sulfamethazine, corn starch, and magnesium stearate was employed. The formulations were wet granulated with a 10% (wt/vol) starch paste in a high shear granulator and dried at 60 degrees C in a convection tray dryer.

Dissolution test development for complex veterinary dosage forms: oral boluses.

Fundamental aspects of electrolyte chemistry were used to design an appropriate dissolution medium with the capacity to maintain sink conditions throughout the test. Dissolution of various bolus dosage forms was studied using USP Apparatus II at various stirring speeds. Complete dissolution of each drug in the designed medium was achieved, and there is evidence that such a dissolution test could be discriminating.