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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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Hybrid biopolymer composites for 3D printing applications
Menčík, Přemysl ; Bakoš, Dušan (referee) ; Dzik, Petr (referee) ; Jančář, Josef (advisor)
This dissertation work deals with the thermic and the mechanical behavior of plasticized bio-plastics and bio-composites for the 3D printing applications. The influence of plasticizer chemical structure on thermic and mechanical properties of plasticized polymeric blends from the poly-3-hydroxybutyrate and the poly lactic acid was investigated. Used plasticizers are based on derivative of citric acid. The influence of plasticizers on polymeric matrix and their compatibility was estimated by gear torque rate of melt mixer, respectively rate of plasticizer migration from the material during higher temperature. The plasticizer structure influence on the glass transition temperature and on the kinetics of crystallization of plasticized material was investigated by modulated differential scanning calorimetry. The behavior of material during 3D printing was also observed. Mechanical properties of printed samples, especially their elongation at break, were determined by tensile tests. The largest softening effect was observed using tributylcitrate plasticizer, where the glass temperature decreased by 35 °C and elongation at break increased by 150% compared to non-plasticized reference material. This plasticized polymeric blend showed also sufficient 3D printing properties and was used as the matrix for composites in the next part of this work. Composites were filled by kaolin, limestone, halloysit, fumed silica, talc, magnesium hydroxide and chopped flax fibers. Particle distribution in composites in dependence of used surface treatment of filler was observed by scanning electron microscopy. The influence of composite filler on rheological properties, crystallization kinetics and thermal stability of composites, was observed by viscometry and differential scanning calorimetry. Their mechanical properties and heat deflection temperature were observed on samples prepared by 3D print. Kaolin in composite material showed homogeneous particle distribution and insignificant nucleation effect and influence on thermic stability. Composite filled by kaolin also showed 18% smaller warping during 3D printing compared to non-filled reference. Consequently kaolin was evaluated as suitable inorganic filler for bioplastic composite intended for 3D print and this composite was used in the following part of this thesis. Method of mathematical prediction of Young's modulus was described for composite samples prepared by 3D print. Composites filled by one type of filler – kaolin, or limestone, resp. by combination of both fillers were investigated on the basis of the micromechanic Halpin-Tsai model modified by the semiempiric multiparametric Cerny's equation. Additive and combinational method of Young's modulus evaluation is used for composites with hybrid filling. Deflection of measured and theoretical Young's modulus value of composite filled with kaolin was decreased by established correction from 21% to 1% and for composites filled with limestone from 13% to 9%. In this manner it is possible to predict the Young's modulus of the samples prepared by 3D print.
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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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Acyclovir release from mucoadhesive matrices
Šišáková, Lenka ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Student: Lenka Šišáková Supervisor of Diploma thesis: PharmDr. Eva Šnejdrová, Ph.D. Title of Diploma thesis: Aciclovir release from mucoadhesive matrices The aim of this diploma thesis was the study of the mucoadhesive parameters of plasticized oligoester of lactic acid and glycolic acid and 3% mannitol as a branching monomer. Knowledge of dissolution testing of drug release from dosage form, principal theories and mechanisms of mucoadhesion and mucoadhesion testing of adhesive formulation is described in theoretical part. Matrices formed from terpolymer of D,L-lactic acid, glycolic acid branched with mannitol and 5 % aciclovir were examined in the experimental part. Triethylcitrate (TEC), ethylpyruvate (EP), methylsalicylate (MS) and ethylsalicylate (ES) were used as plasticizers. Dissolution test has been done. Hydrated mucin from porcine stomach was used as a base. Phosphate-citrate buffer pH 7.4 was used as a dissolution medium. Dissolution was defined as a quantity of released aciclovir in to the dissolution medium after 15, 30, 60 and 90 minutes. The quantity of the released aciclovir was defined by a spectrophotometry. In 90 minutes was released 43 % of aciclovir from the matrice...
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Effect of plasticization on rheological properties of oligoester of lactic acid and glycolic acid branched with dipentaerythritol
Bílková, Klára ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
CHARLES UNIVERSITY IN PRAGUE Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical technology Name of the student: Klára Bílková Title of diploma thesis: Influence of plastification on rheological properties of oligoester of lactic acid and glycolic acid branched with dipentaerythritole Consultant: PharmDr. Eva Šnejdrová, Ph.D. The aim of this diploma thesis was the study of rheological properties of the oligoester of DL-lactic and glycolic acids branched with 1% of dipenthaerythritol (1D) and plasticized with 6 various plasticizers in increasing concentrations. Theoretical part was devoted to fundamentals of rheology and measurements of viscosity using rotational viscometers. It describes basic types and constructions of rotational rheometers and summarizes basic facts about bioadhesion and use of rheological method for assessment of bioadhesion. There were prepared matrices from oligoester 1D and plasticizers in concentrations of 20 %, 30 % and 40 % in the experimental part. These plasticizers were tested: ethyl pyruvate, ethyl salicylate, methyl salicylate, triacetin, tributyrin and triethyl citrate. Rheological properties were examinated at 37 řC using spindle viscometer and at 37 řC and 50 řC using rotational rheometer. Rheograms were used to characterize flow properties of tested...
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