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Stability of vesicular complexes against changes in their concentration
Velichová, Veronika ; Marková, Kateřina (referee) ; Mravec, Filip (advisor)
This bachelor thesis is focused on the stability of vesicular systems that consist of ion pair amphiphile. These catanionic vesicles were prepared from single-chained surfactants CTAB cetyltrimethylammonium bromide) and SDS (sodium dodecyl sulphate), which were stabilized by adding double-chained surfactant DODAC (dimethyldioctadecylammonium chloride) with 43 mol.% cholesterol. The aim of the thesis was to verify the stability of vesicular systems against changes in their concentration. For the measurement, a concentration series was prepared by diluting vesicles with deionized water. The stability was evaluated by dynamic (DLS) and electrophoretic (ELS) light scattering measurements at weekly intervals for four weeks. By DLS method were determined the average values of the size of vesicles and their changes during the measurement, the method ELS provided the information about changes of charge with different concentration in time. Samples with a higher concentration, i.e. no dilution till tenfold dilution of the vesicle solution, were marked as stable, higher values of average sizes and lower values of zeta potential were measured at solution with lower concentrations, according to which such diluted vesicles can be described as unstable. There were also visual observations made, but no visible aggregation in the solutions was observed. Furthermore, the aggregation behavior of the vesicles was observed by fluorescence spectroscopy using pyrene as fluorescent probe.
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Stability of vesicular complexes against changes in their concentration
Velichová, Veronika ; Marková, Kateřina (referee) ; Mravec, Filip (advisor)
This bachelor thesis is focused on the stability of vesicular systems that consist of ion pair amphiphile. These catanionic vesicles were prepared from single-chained surfactants CTAB cetyltrimethylammonium bromide) and SDS (sodium dodecyl sulphate), which were stabilized by adding double-chained surfactant DODAC (dimethyldioctadecylammonium chloride) with 43 mol.% cholesterol. The aim of the thesis was to verify the stability of vesicular systems against changes in their concentration. For the measurement, a concentration series was prepared by diluting vesicles with deionized water. The stability was evaluated by dynamic (DLS) and electrophoretic (ELS) light scattering measurements at weekly intervals for four weeks. By DLS method were determined the average values of the size of vesicles and their changes during the measurement, the method ELS provided the information about changes of charge with different concentration in time. Samples with a higher concentration, i.e. no dilution till tenfold dilution of the vesicle solution, were marked as stable, higher values of average sizes and lower values of zeta potential were measured at solution with lower concentrations, according to which such diluted vesicles can be described as unstable. There were also visual observations made, but no visible aggregation in the solutions was observed. Furthermore, the aggregation behavior of the vesicles was observed by fluorescence spectroscopy using pyrene as fluorescent probe.
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Influence of formulation factors on the characteristics of terbinafine loaded nanoparticles.
Barák, Vlastimil ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL TECHNOLOGY Author: Vlastimil Barák Title of Diploma thesis The influence of formulation factors on the characteristics of terbinafine loaded nanoparticles Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Consultant: Mgr. Juraj Martiška The diploma thesis is focused on biodegradable polymer nanoparticles loaded by terbinafine based on the copolymer of glycolic and lactic acid branched on polyacrylic acid. The nanoprecipitation method was employed, and the influence of formulation factors on nanoparticle characteristics was studied. The following formulation factors were the concentration of the polymer, the amount of terbinafine, and the concentration of surfactant. Nanoparticles of 120 nm to 300 nm were obtained depending on the preparation conditions. The nanoparticle polydispersity was in all cases from 0.080 to 0.230. The prepared nanoparticles were stable, as evidenced by zeta potential values above 38 mV. A positive zeta potential is desirable for dermal and mucosal adhesion in the topical and ocular application of nanoparticles with terbinafine. The amount of polymer used to form nanoparticles has the greatest effect on particle size. With increasing polyester concentration in the internal phase, the size of the...
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Terbinafine-loaded biodegradable polymeric systems for topical administration
Pokorná, Tereza ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL TECHNOLOGY Author: Tereza Pokorná Title of Diploma thesis Terbinafine-loaded biodegradable polymeric systems for topical administration Supervisor: PharmDr. Eva Šnejdrová, Ph.D. In the diploma thesis the released properties of solid dispersions with terbinafine, based on polyesters of D,L-lactic acid and glycol acid, branched with pentaerythritol and tripentaerythritol are studied. The theoretical part deals with solid dispersions, their classification and methods of preparation, methods of drug dissolution testing, properties, effect, use of terbinafine and preparations containing terbinafine. In the experimental part, solid dispersions were prepared by the melting method. The drug was incorporated into the polyester in the form of a hydrochloride or a base in a concentration of 10 % or 20 %. Some systems were plasticized with 30% triethyl citrate. Thin layers were formulated from solid dispersions, and drug dissolution tests were performed on phosphate buffer pH 7.4 at 37 řC. Assay of terbinafine released was performed spectrophotometrically at 223 nm and ultra-high performance liquid chromatography. Based on the results of this diploma thesis, it can be clearly stated that the suitable carrier of terbinafine...
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Influence of formulation factors on the characteristics of terbinafine loaded nanoparticles.
Barák, Vlastimil ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL TECHNOLOGY Author: Vlastimil Barák Title of Diploma thesis The influence of formulation factors on the characteristics of terbinafine loaded nanoparticles Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Consultant: Mgr. Juraj Martiška The diploma thesis is focused on biodegradable polymer nanoparticles loaded by terbinafine based on the copolymer of glycolic and lactic acid branched on polyacrylic acid. The nanoprecipitation method was employed, and the influence of formulation factors on nanoparticle characteristics was studied. The following formulation factors were the concentration of the polymer, the amount of terbinafine, and the concentration of surfactant. Nanoparticles of 120 nm to 300 nm were obtained depending on the preparation conditions. The nanoparticle polydispersity was in all cases from 0.080 to 0.230. The prepared nanoparticles were stable, as evidenced by zeta potential values above 38 mV. A positive zeta potential is desirable for dermal and mucosal adhesion in the topical and ocular application of nanoparticles with terbinafine. The amount of polymer used to form nanoparticles has the greatest effect on particle size. With increasing polyester concentration in the internal phase, the size of the...
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Influence of formulation factors on the characteristics of terbinafine loaded nanoparticles.
Barák, Vlastimil ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL TECHNOLOGY Author: Vlastimil Barák Title of Diploma thesis The influence of formulation factors on the characteristics of terbinafine loaded nanoparticles Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Consultant: Mgr. Juraj Martiška The diploma thesis is focused on biodegradable polymer nanoparticles loaded by terbinafine based on the copolymer of glycolic and lactic acid branched on polyacrylic acid. The nanoprecipitation method was employed, and the influence of formulation factors on nanoparticle characteristics was studied. The following formulation factors were the concentration of the polymer, the amount of terbinafine, and the concentration of surfactant. Nanoparticles of 120 nm to 300 nm were obtained depending on the preparation conditions. The nanoparticle polydispersity was in all cases from 0.080 to 0.230. The prepared nanoparticles were stable, as evidenced by zeta potential values above 38 mV. A positive zeta potential is desirable for dermal and mucosal adhesion in the topical and ocular application of nanoparticles with terbinafine. The amount of polymer used to form nanoparticles has the greatest effect on particle size. With increasing polyester concentration in the internal phase, the size of the...
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Influence of formulation factors on the characteristics of terbinafine loaded nanoparticles.
Barák, Vlastimil ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL TECHNOLOGY Author: Vlastimil Barák Title of Diploma thesis The influence of formulation factors on the characteristics of terbinafine loaded nanoparticles Supervisor: PharmDr. Eva Šnejdrová, Ph.D. Consultant: Mgr. Juraj Martiška The diploma thesis is focused on biodegradable polymer nanoparticles loaded by terbinafine based on the copolymer of glycolic and lactic acid branched on polyacrylic acid. The nanoprecipitation method was employed, and the influence of formulation factors on nanoparticle characteristics was studied. The following formulation factors were the concentration of the polymer, the amount of terbinafine, and the concentration of surfactant. Nanoparticles of 120 nm to 300 nm were obtained depending on the preparation conditions. The nanoparticle polydispersity was in all cases from 0.080 to 0.230. The prepared nanoparticles were stable, as evidenced by zeta potential values above 38 mV. A positive zeta potential is desirable for dermal and mucosal adhesion in the topical and ocular application of nanoparticles with terbinafine. The amount of polymer used to form nanoparticles has the greatest effect on particle size. With increasing polyester concentration in the internal phase, the size of the...
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Terbinafine-loaded biodegradable polymeric systems for topical administration
Pokorná, Tereza ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL TECHNOLOGY Author: Tereza Pokorná Title of Diploma thesis Terbinafine-loaded biodegradable polymeric systems for topical administration Supervisor: PharmDr. Eva Šnejdrová, Ph.D. In the diploma thesis the released properties of solid dispersions with terbinafine, based on polyesters of D,L-lactic acid and glycol acid, branched with pentaerythritol and tripentaerythritol are studied. The theoretical part deals with solid dispersions, their classification and methods of preparation, methods of drug dissolution testing, properties, effect, use of terbinafine and preparations containing terbinafine. In the experimental part, solid dispersions were prepared by the melting method. The drug was incorporated into the polyester in the form of a hydrochloride or a base in a concentration of 10 % or 20 %. Some systems were plasticized with 30% triethyl citrate. Thin layers were formulated from solid dispersions, and drug dissolution tests were performed on phosphate buffer pH 7.4 at 37 řC. Assay of terbinafine released was performed spectrophotometrically at 223 nm and ultra-high performance liquid chromatography. Based on the results of this diploma thesis, it can be clearly stated that the suitable carrier of terbinafine...
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Terbinafine-loaded biodegradable polymeric systems for topical administration
Pokorná, Tereza ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY FACULTY OF PHARMACY IN HRADEC KRÁLOVÉ DEPARTMENT OF PHARMACEUTICAL TECHNOLOGY Author: Tereza Pokorná Title of Diploma thesis Terbinafine-loaded biodegradable polymeric systems for topical administration Supervisor: PharmDr. Eva Šnejdrová, Ph.D. In the diploma thesis the released properties of solid dispersions with terbinafine, based on polyesters of D,L-lactic acid and glycol acid, branched with pentaerythritol and tripentaerythritol are studied. The theoretical part deals with solid dispersions, their classification and methods of preparation, methods of drug dissolution testing, properties, effect, use of terbinafine and preparations containing terbinafine. In the experimental part, solid dispersions were prepared by the melting method. The drug was incorporated into the polyester in the form of a hydrochloride or a base in a concentration of 10 % or 20 %. Some systems were plasticized with 30% triethyl citrate. Thin layers were formulated from solid dispersions, and drug dissolution tests were performed on phosphate buffer pH 7.4 at 37 řC. Assay of terbinafine released was performed spectrophotometrically at 223 nm and ultra-high performance liquid chromatography. Based on the results of this diploma thesis, it can be clearly stated that the suitable carrier of terbinafine...
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