Studies on the Vitrified and Cryomilled Bosentan.

In this paper, several experimental techniques [X-ray diffraction, differential scanning calorimetry (DSC), thermogravimetry, Fourier transform infrared spectroscopy, and broad-band dielectric spectroscopy] have been applied to characterize the structural and thermal properties, H-bonding pattern, and molecular dynamics of amorphous bosentan (BOS) obtained by vitrification and cryomilling of the monohydrate crystalline form of this drug. Samples prepared by these two methods were found to be similar with regard to their internal structure, H-bonding scheme, and structural (α) dynamics in the supercooled liquid state. However, based on the analysis of α-relaxation times (dielectric measurements) predicted for temperatures below the glass-transition temperature (), as well as DSC thermograms, it was concluded that the cryoground sample is more aged (and probably more physically stable) compared to the vitrified one.

Application of Dominance-Based Rough Set Approach for Optimization of Pellets Tableting Process.

Multiple-unit pellet systems (MUPS) offer many advantages over conventional solid dosage forms both for the manufacturers and patients. Coated pellets can be efficiently compressed into MUPS in classic tableting process and enable controlled release of active pharmaceutical ingredient (APIs). For patients MUPS are divisible without affecting drug release and convenient to swallow.

Compressibility of gastroretentive pellets coated with Eudragit NE using a single-stroke and a rotary tablet press.

In this study, 15 kinds of powders with different compression mechanisms were used in the process of filling-binding substances in tablets with pellets. Applied substances possessed dominant brittle time-independent mechanism or time-dependent viscoplastic, viscoelastic mechanism of compression. Using 6 kN compression force in a single-stroke tablet press during 150 ms of compression, damage to the polymer film and pellet core was found in all formulations.

Influence of the type of cellulose on properties of multi-unit target releasing in stomach dosage form with verapamil hydrochloride.

Microcrystalline cellulose (MCC) and powdered cellulose (PC) are commonly used excipients for solid dosage forms e.g., pellets.

Influence of acrylic esters and methacyrlic esters on flotation of pellets and release rate of verapamil hydrochloride.

Eudragit RL (ERL) and Eudragit RS (ERS) are biocompatible cationic copolymers, pH-independent and insoluble in aqueous environment. In this study drug delivery system consisting of a capsule filled with floating pellets with verapamil hydrochloride (VH) is proposed. The release of VH in the stomach results in better solubility in an acid gastric environment in vivo and may result in greater amount of the VH absorbed and its higher concentration in plasma.

Compressibility of floating pellets with verapamil hydrochloride coated with dispersion Kollicoat SR 30 D.

The purpose of this study was to work out a method of compression of floating pellets with verapamil hydrochloride (VH) in a dose of 40 mg. It was assumed that this form should reside in the stomach floating for several hours and gradually release the drug in a controlled way. Compression of pellets into tablets, being a modern technological process, is much more perfect than enclosing them in a hard gelatin capsule.