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Adhesive and rheological properties of chitosan-based mixtures
Korpasová, Marie ; Šnejdrová, Eva (advisor) ; Mužíková, Jitka (referee)
CHARLES UNIVERSITY IN PRAGUE Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Name and surname: Marie Korpasová Title of diploma thesis: Adhesive and rheological properties of mixtures based on chitosan Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Diploma thesis deals with evaluation of rheological and adhesive properties of compounds for matrix tablets formulation, based on Chitosan with addition of retardant compound. The retardant compound consists of Sodium Alginate and Hypromellose in concentrations of 30 %, 40 % and 50 %. Theoretical part describes Chitosan, Sodium Alginate and Hypromellose. As next is division of matrix tablets. Theoretically is also described evaluation of rotational, oscillational and adhesive testing which was used in practical part. From viscosity curves can be seen, that viscosity is decreasing with increasing stress. Viscosity increases with increasing concentration of Sodium Alginate and Hypromellose. Oscillational testing is better for gel characterization, because it provides lower stress on test samples. Samples of given compound were prepared by hydrating with phosphate buffer of pH 6,8. Coefficient of consistency K and index flow rate n characterize rheological behaviour of gels. Viscoelastic compounds behave like solids with plastic...
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Adhesive and rheological properties of chitosan-based mixtures
Korpasová, Marie ; Šnejdrová, Eva (advisor) ; Mužíková, Jitka (referee)
CHARLES UNIVERSITY IN PRAGUE Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Name and surname: Marie Korpasová Title of diploma thesis: Adhesive and rheological properties of mixtures based on chitosan Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Diploma thesis deals with evaluation of rheological and adhesive properties of compounds for matrix tablets formulation, based on Chitosan with addition of retardant compound. The retardant compound consists of Sodium Alginate and Hypromellose in concentrations of 30 %, 40 % and 50 %. Theoretical part describes Chitosan, Sodium Alginate and Hypromellose. As next is division of matrix tablets. Theoretically is also described evaluation of rotational, oscillational and adhesive testing which was used in practical part. From viscosity curves can be seen, that viscosity is decreasing with increasing stress. Viscosity increases with increasing concentration of Sodium Alginate and Hypromellose. Oscillational testing is better for gel characterization, because it provides lower stress on test samples. Samples of given compound were prepared by hydrating with phosphate buffer of pH 6,8. Coefficient of consistency K and index flow rate n characterize rheological behaviour of gels. Viscoelastic compounds behave like solids with plastic...
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Rheological behaviour of mixtures for freeze-drying
Vavřich, Dominik ; Šnejdrová, Eva (advisor) ; Šklubalová, Zdeňka (referee)
CHARLES UNIVERSITY Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Name of author: Dominik Vavřich Title of diploma thesis: Rheological behaviour of mixtures for freeze-drying Supervisor: PharmDr. Eva Šnejdrová, Ph.D. The diploma thesis deals with the evaluation of rheological properties of aqueous dispersions of fish gelatin and carrageenans intended for lyophilization. Theoretical part of this work is dedicated to the characterization of fish gelatin and carrageenans which were used for preparation of the mixtures in experimental part of this work. Characterization of an oral cavity from an application of medicaments point of view and an orally disintegrating tablets of the medicine with a focus on the lyophilized tablets are also presented. Mixtures of the fish gelatin and the carrageenans were prepared in the experimental part of the work. Their rheological behaviour employing an absolute rotational rheometer Kinexus Pro+ was measured and evaluated. Also, the testing of the rheological characteristics of these materials transformed into the freeze-dried tablets was performed. Nonlinear viscous curves were obtained, and they were mathematically evaluated by the Power law model. Pseudoplastic behaviour of the mixtures can be derived from the results of acquired...
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