Isomalt, a sugar alcohol, was melt-extruded prior to compression in order to improve its tabletting properties. After fusion, crystalline isomalt was transformed into an amorphous form as shown by X-ray diffraction and differential scanning calorimetry (DSC). The tabletting properties of amorphous isomalt were dramatically improved.
View Article and Find Full Text PDFJ Control Release
August 2001
The objective of developing a double matrix system consisting of a hot stage extruded starch pipe surrounding a hot stage extruded and drug-containing starch core, was to obtain a monolithic matrix system applicable in the domain of sustained drug release. The behaviour of the systems was evaluated through dissolution testing and through a randomised crossover bioavailability study on nine male volunteers. All double matrix systems showed in vitro a nearly constant drug release profile after an initial slower release phase of 4 h.
View Article and Find Full Text PDFThe aim of this study was to evaluate the influence of the formulation composition on the characteristics of starch based hot stage extrudates in order to obtain high quality and high efficacy matrices for controlled drug delivery. Their characteristics were compared to those of a reference formulation, for which in vivo data were available. The influence of the starch type, the plasticizer and the lubricant were investigated.
View Article and Find Full Text PDFIsomalt is a sugar substitute with a wide range of potential pharmaceutical applications as a result of its physicochemical properties. Four grades of this material were evaluated for their physical characteristics. Only Palatinit(R) C and F exhibited potential characteristics for direct compression.
View Article and Find Full Text PDFThe influence of the process parameters on the characteristics of matrix formulations produced by means of hot stage extrusion was investigated using three experimental designs. The first one was designed to evaluate the importance of the screw speed (150-450 rpm) and the feed rate (2-12 kg/h), while the second and the third were designed to study the importance of the temperature profile (60-120 degrees C). The extrudates were produced with a laboratory twin screw extruder equipped with a 3-mm cylindrical die.
View Article and Find Full Text PDFThe aim of the study was to develop a starch based hot stage extrusion formulation for controlled drug delivery and to evaluate its in vivo behavior. The extrusion mixture consisted of 53% corn starch as the matrix forming agent, 15% sorbitol as a plasticizer, 30% theophylline monohydrate as the model drug and 2% glyceryl monostearate as a lubricant. The extrudates were produced by means of a corotating twin screw extruder of APV Baker equipped with a twin screw powder feeder and a 3-mm cylindrical die.
View Article and Find Full Text PDFKetoprofen (KTP) is a chiral non-steroidal anti-inflammatory drug (NSAID) of the propionic acid class, approved by the FDA for the allevation of pain associated with musculoskeletal disorders in horses. The present study was designed to examine the bioavailability of ketoprofen enantiomers after rectal administration of the racemate to healthy horses. One gram of racemic ketoprofen was injected intravenously and administered rectally as a fat based suppository in a cross-over design study (n = 4).
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