Posts tagged with "state"
04. October 2018
Praziquantel is an antiparasitic drug used for decades. Currently, the praziquantel commercial preparation is a racemic mixture, inwhich only the levo-enantiomer possesses anthelmintic activity. The knowledge of its properties in the solid state and other chemical-physical properties is necessary for improving its efficacy andapplications. Drug solid dispersions were prepared with calcium carbonate at 1:5 drug to excipient weight ratio by solventevaporation method. Then, the modification of the...
28. March 2018
Production of nanosuspension for drug bioavailability improvement has been accepted and frequently used in pharmaceutical industry. Normally, the preparation started from crystalline drug. However, some previous studies found that amorphous drug powder obtained from processes such as spray-drying might contribute to nanosizing process, i.e. reduced homogenization cycles and smaller achievable particle size. The mechanism behind this improved behavior was still unclear. In order to...
21. December 2016
Abstract Synergetic role of polymer blending on dissolution of amorphous solid dispersion was investigated. Dissolution rates of hypromellose (HPMC) and methacrylic acid copolymer (EUD) from the HPMC/EUD spray-dried sample (SPD) were improved compared to those of each single polymer SPD. Differential scanning calorimetry measurements revealed that the structural change in HPMC following heating was inhibited by co-spray-drying with EUD, suggesting an intermolecular interaction between the...
14. September 2016
Abstract This study investigated how the inclusion of magnesium oxide (MgO) maintained tablet hardness during storage in an unpackaged state. Tablets were prepared with a range of MgO levels and stored at 40°C with 75% relative humidity for up to 14 d. The hardness of tablets prepared without MgO decreased over time. The amount of added MgO was positively associated with tablet hardness and mass from an early stage during storage. Investigation of the water sorption properties of the tablet...
27. July 2016
Granules with release-sustaining properties were developed by twin screw hot melt granulation (HMG) using a combination of stearic acid (SA) and high molecular weight polyethylene oxide (PEO) as matrix for a highly water soluble model drug, metoprolol tartrate (MPT). Earlier studies demonstrated that mixing molten SA and PEO resulted in hydrogen bond formation between hydroxyl groups of fatty acid molecules and ether groups in PEO chains. These molecular interactions might be beneficial in...
18. March 2016
Aminoglycosides are scarcely absorbed via the gastro-intestinal tract, and for that reason they are often administered by injection, which is an invasive administration technique. Tobramycin for the treatment of pulmonary infections is currently also nebulised after early inhalation studies with this drug in the 1980s showed promising results against Pseudomonas aeruginosa in Cystic Fibrosis patients. However, nebulisation has many disadvantages. The technique is ineffective, laborious and...
06. January 2016
The structural and thermodynamic properties of glassy carbohydrate matrices for the encapsulation and biostabilization of sensitive bioactive compounds, such as pharmaceutically active proteins and oxidation-sensitive compounds, are reviewed in the context of the plasticization and antiplasticization of glassy carbohydrates of intermediate and high molecular weight by low molecular weight diluents. More
29. November 2015
An increasing number of newly discovered drugs are poorly water-soluble and the use of natural and synthetic lipids to improve the oral bioavailability of these drugs by utilizing the digestion pathway in-vivo has proved an effective formulation strategy. The mechanisms responsible for lipid digestion and drug solubilisation during gastrointestinal transit have been explored in detail, but the implications of drug precipitation beyond the potential adverse effect on bioavailability have...