Στη μελέτη αυτή εξετάστηκε η ύπαρξη σχέσης μεταξύ παραμέτρων διαβρεκτικότητας (συντελεστής διασποράς, λ, και έργο συνάφειας, Wa), της αντίστασης κατά την υγρή ανάμιξη (ροπή στρέψης), της ποσότητας του κοκκοποιητικού υγρού που απαιτείται για την επίτευξη ασφαλούς σχηματισμού υγρών κόκκων (χοανοειδής συσσωμάτωση), της αντοχής σε εφελκυσμό και της αντίστασης στη συμπύκνωση υγρών κόκκων ενός απλού κονιοποιημένου υλικού (ενός συστατικού). Επίthe sticking ability of the components. As granulating conditions were evaluated the resistance of wet mixing, expressed as torque exerted on the mixing vessel, and the consumption of granulation liquid, corresponding to optimal production of usable granulation (funicular agglomeration state). The final dried granules were characterised on the basis of their size, shape, friability and content uniformity, as well as on their dissolution rate. Systems of single component powder (lactose and sulfadiazine) with different liquid (water, isopropanol, their mixture and paraffin) were initially examined. Then binary powder mixtures comprising hydrophilic and hydrophobic components we ...
The aim of this work was to elucidate relations between parameters of solid-liquid interactions, of wet granulating conditions and physicomechanical properties of final dried granules. As parameters of solid-liquid interactions were selected the spreading coefficient, λ, the work of adhesion, Wa, the swelling and the sticking ability of the components. As granulating conditions were evaluated the resistance of wet mixing, expressed as torque exerted on the mixing vessel, and the consumption of granulation liquid, corresponding to optimal production of usable granulation (funicular agglomeration state). The final dried granules were characterised on the basis of their size, shape, friability and content uniformity, as well as on their dissolution rate. Systems of single component powder (lactose and sulfadiazine) with different liquid (water, isopropanol, their mixture and paraffin) were initially examined. Then binary powder mixtures comprising hydrophilic and hydrophobic components were studied and finally ternary mixtures containing different drugs (Naproxen, Diclofenac, Indomethacin and Ibuprofen) additional to the hydrophilic and hydrophobic component. Hydroxy-propyl-cellulose (HPC) and hydroxy-propyl-methyl-cellulose (HPMC) were employed as hydrophilic component and hydrogenated vegetable oil (Emvelop) as hydrophobic component. As granulating liquid was used water and isopropanol for the binary and isopropanol for the ternary powder mixes. From the study of single component powders, it was found that, for liquids of similar viscosity, the work of adhesion (Wa) is related to the amount of granulating liquid corresponding to the mean funicular agglomeration state, (S3 + S4)/2 and to the tensile strength and resistance to densification of the wet agglomerates. No correlation was found between the torque and the parameters of solid-liquid interactions examined. This absence of correlation was attributed to the effect of micromeritic properties of wet agglomerates on the torque besides to that of the solid - liquid interactions. The study of binary powder mixes has shown that swellability of the hydrophilic component together with its content determine the consumption of granulating liquid. However, the wet mixing resistance seems to be dependent on both the sticking and the swelling ability of the components. Swelling in a relatively low degree might increase the sticking and result in increased torque (cases of HPC with water and isopropanol and case of HPMC with water). On the contrary, swelling in a relatively high degree might decrease the sticking and result in great increase of the torque (case of HPMC with isopropanol) due to the increased elasticity of swollen particles and greater contact area and stronger interparticle frictional forces. However, the granulating liquid consumption, for the binary systems, depends on the swellability, while the wet mixing resistance depends on the sticking ability and the elastic deformation of the swollen particles of the hydrophilic component. From the study of ternary powder mixes it was found that wet mixing resistance depends on the nature and the content of both the hydrophilic component and the drug incorporated. The consumption of granulating liquid (isopropanol) mainly depends on the content and the swellability of the hydrophilic component and on the solubility and wettability of the drug (third component). As far as the physicomechanical properties of the dried pharmaceutical granules are concerned, the swelling and sticking ability of the wetted solid components determined them. Granules of largest size and narrowest size distribution corresponded to HPMC, which shows highest swellability in isopropanol used as granulating liquid. Fluidity of HPC dissolved in isopropanol during the wet mixing resulted in the formation of granules with highest sphericity, while the great swelling and subsequent elastic deformation of HPMC resulted in granules of least shape uniformity and sphericity. Reduced friability of granules containing HPMC was observed, which was also attributed to higher swelling ability. Furthermore, intergranular porosity was higher for granules containing HPC due to their smaller size and wider size distribution, while the intragranular porosity was higher for granules containing HPMC, probably due to higher swelling ability and subsequent higher elastic deformation.
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Εναλλακτικός τίτλος | Wet granulation and formation controlled released solid dosage forms
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| Συγγραφέας | Κιόρτσης, Ευστράτιος (Πατρώνυμο: Νικόλαος) |
| Ημερομηνία | 2001 |
| Ίδρυμα | Αριστοτέλειο Πανεπιστήμιο Θεσσαλονίκης (ΑΠΘ). Σχολή Επιστημών Υγείας. Τμήμα Φαρμακευτικής. Τομέας Φαρμακευτικής Τεχνολογίας. Εργαστήριο Φαρμακοτεχνίας και Ελέγχου Φαρμάκων |
| Εξεταστική επιτροπή | Μαλαματάρης Σταύρος
Κτίστης Γεώργιος
Μπρούσαλη-Τσιφτσόγλου Θεοδώρα
Καράμπελας Αναστάσιος
Μαχαίρας Παναγιώτης
Γεωργακάκης Εμμανουήλ
Κουντουρέλλης Ιωάννης |
| Επιστημονικό πεδίο | Ιατρική και Επιστήμες Υγείας
Βασική Ιατρική |
| Λέξεις-κλειδιά | Διαβρεκτικότητα; Υγρή κοκκοποίηση; Πρόσληψη υγρού; Κολλητικότητα; Ελεγχόμενη αποδέσμευση; Υδρόφιλη μήτρα; Υδρόφοβη μήτρα |
| Χώρα | Ελλάδα |
| Γλώσσα | Ελληνικά |
| Άλλα στοιχεία | 225 σ., εικ. |
