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Design, Developement and Implementation of a Round Timber Evidence Software Application
Štanglica, Jiří ; Dittrich, Milan (referee) ; Dydowicz, Petr (advisor)
This thesis is focused on requirements analysis of a sawmill company for a new timber stock evidence system and based on the analysis describes the process of development of the system. The process covers architecture and structure design as well as data storage solution. Apart from the development stage itself, it also covers the implementation of the system in the company’s environment and economic evaluation of the process. The system is being developed using the Javascript programming language and uses modern technologies such as React, Node.js and MongoDB.
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Nanofibrous membranes as drug delivery systems II
Stránská, Denisa ; Doležal, Pavel (advisor) ; Dittrich, Milan (referee) ; Maťha, Vladimír (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department: Pharmaceutical technology Candidate: Ing. Denisa Stránská Supervisor: Doc. RNDr. Pavel Doležal, CSc. Title of Doctoral Thesis: Nanofibrous membranes as drug delivery systems Nanofibres are material structures of unique properties that are well-useable in many exciting areas, including medical products. In the field of air filtration, different types of nanofibre filters are produced industrially. On the other hand, in the area of medicated nanofibres, there is still a major barrier for production, and hence the commercial use of nanofibres, especially due to the low weight and required content uniformity of the final products. Electrospinning technology is the most promising in this context, however, no results on the evaluation of nanofibrous products intended for the systemic administration of drugs obtained by certified manufacturing process have been published. In this doctoral thesis the individual steps of the nanofibrous products production are described, experimentally evaluated in compliance with good manufacturing practice and documented with an emphasis on the validation procedures and thus on the desired repeatability of all steps leading to the production of the final product. Validation processes included...
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Evaluation of rheological and adhesive properties of semisolid excipients
Trhlíková, Anna ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
Charles University, Faculty of Pharmacy in Hradci Králové Department of Pharmaceutical Technology Candidate Mgr. Anna Trhlíková Consultant PharmDr. Eva Šnejdrová, Ph.D. Title of Thesis Evaluation of rheological and adhesive properties of semisolid excipients Thesis deals with the evaluation of rheological and adhesive properties of semisolid excipients by rotary rheometer Kinexus. In the theoretical part, bioadhesion is defined, testing methods of bioadhesion of semisolid excipients are described, and methods for testing of rheological properties. Rheological behaviour of semisolid excipients was evaluated by flow and viscosity curves analysed using Power Law and Herschel - Bulkley model. Squeeze and pull off test with analyses was used to evaluate the adhesion properties on a rotary rheometer. As model excipients Adeps lanae, Adeps lanae cum aqua, Alcoholis cetylici unguentum, Alcoholis cetylici cremor, Cremor basalis, Vaselinum album and Vaselinum album after adding 5% of Cera alba, 10%, of Cera alba, or 5% of Paraffinum solidum were used. Consistency characterized by a coefficient K of Power law model decreases in the order Adeps lanae cum aqua, Adeps lanae, Vaselinum album, Cremor basalis. Spreadability assessed by flow behaviour index n of Power law model decreases in the order Vaselinum...
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Degradation of branched polyesters in the aqueous medium with various ionic force
Nolová, Veronika ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Candidate: Veronika Nolová Supervisor: Doc. RNDr. Milan Dittrich, CSc. Title of diploma thesis: Biodegradation of branched polyesthers in the aquous medium with various ionic force The theoretical part of the diploma thesis deals with the physical and chemical properties of the copolymer of lactid and glycolic acid (PLGA). It is also mentioned mechanism of biodegradation and factors influencing this process and biocompatibility. It also deals with the implants, the use of PLGA and other polymers in in situ forming implants. Then briefly mentioned the use of biopolymers in medicine. Within the experimental part, the influence of ionic strength on the degradation of branched polyesters, namely the PLGA branched mannitol and linear PLGA. Polymeric matrices were stored at 37 ř C in phosphate buffer at various concentrations and in an aqueous medium without addition of ions. Subsequently, the calculated value of degree of swelling and the degree of erosion during a period of 1, 3, 7, 14 and 21 days. The results confirmed that the tested linear polymer PLGA swells more with decreasing ionic strength, but in an aqueous medium swells limited. Branched polymers also swell more in an environment...
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Influence of reduction agent on granulometric parameters of silver nanoparticles
Vojtková, Katarína ; Dittrich, Milan (advisor) ; Berka, Pavel (referee)
Charles University in Prague Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Candidate: Katarína Vojtková Supervisor: Doc.RNDr. Milan Dittrich, CSc. Title of diploma thesis: Influence of reduction agent on granulometric parameters of silver nanoparticles The aim of this work is to test the influence of different technological parameters on the production of silver nanoparticles. The method used along the experiments was the Tollens reduction method. As reduction agents, there were used various monosaccharides, mainly glucose, oligosaccharides, maltose, lactose and branched polysaccharide Litesse® Ultra in different concentrations. There were used mixtures of two reducing agents as well as addition of surfactants. The concentration of silver reducing ions was increased also. The work contains comparison of the effects of different concentrations of the reducing agents used and also comparison of any changes of the conditions used for the preparation samples (e.g. freezing). Both phases of nucleation and growth were modified either by microwave radiation or ultrasound irradiation. In case of the later the samples showed very small nanoparticles with an average intensity diameter of 20 nm. The outcoming results are presented in tables and pictures. The resulting products...
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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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Intrinsic viscosity and interfacial tension of solutions polyester and polyesteramides drug carriers
Šanderová, Martina ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
Viscosity and interfacial tension of the solutions of polyesters and polyesteramides carriers of drugs. Student: Mgr. Martina Šanderová Tutor: Assoc. Prof. Dr. Milan Dittrich, PhD. Depart od Pharmaceutical Technology, Faculty of Pharmacy in Hradec Králové, Charles University in Prague, Czech Republic Surface activity and intrinsic viscosity of the solutions of various carriers of the type of polyesters and polyesteramides were studied. The theoretical part of the thesis is focused on the basic informations concerning viscosity as phenomenon, surface activity of the solutions of polymers, biodegradable polymers and their properties, and polyesters of aliphatic hydroxyacids. In the experimental part of the thesis was evaluated viscosity and interfacial tension of the solutions of various carriers in chloroform used as solvent. Interfacial tension was measured by Wilhelmy plate method, and intrinsic viscosity was calculated from kinematic viscosity, from their one-point values, by the Solomon-Ciuta method. All the studied oligomeric and polymeric carries were tensioactive. Interfacial tension between aqueous and chloroform phases was influenced by molecular weight of the used compounds, their degree of branching, by flexibility of their chains and their concentracion also. Calculated values of...
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Adhesivity and Viscosity of the Branched Oligoesters
Bacílková, Anna ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
Theoretic part deals with theories of bioadhesion, characteristics of bio- and mucoadhesives. Routs of application are analysed in more detail. Theoretic part is concluded with testing of bioadhesion. Experimental part of thesis investigates rheological and adhesive properties of plasticized oligoesters of D,L - lactic acid and glycolic acid in ratio 1:1 branched with pentaerythritol or tripentaerythritol. Adhesivity was measured on the Material testing machine T1-FR050TH.A1K Zwick/Roell as maximal force Fmax required to detach the polymer system from substrate. These values were converted to the size of the contact area. Viscosity of samples was measured using viscosimeter Brookfield DV-E with an adaptor for small sample amount by 37řC and 50řC temperature. From the outcomes of made experiments follow that carriers with higher molar mass possess higher dynamic viscosity, the lowest dynamic viscosity was found at carrier with the lowest molar mass. The lowest adhesive force was found at carrier 1P with relative low degree of branching g'= 0,59 and middle molar mass Mw = 8400 g/mol. Adhesivity of other carriers was significantly higher, in range from 49.26 mN/mm2 to 65.97 mN/mm2 . Acyclovir release from branched carriers differs particularly at initial phase. Carrier 3P with the digest molar mass...
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Formulation of Submicroscopical Particles from Branched Oligoesters
Seidlová, Marie ; Dittrich, Milan (advisor) ; Šnejdrová, Eva (referee)
Charles University in Prague, Faculty of Pharmacy in Hradec Králové Department of farmaceutical technology Candidate Mgr. Marie Seidlová Consultant Doc. RNDr. Milan Dittrich, CSc. Title of Thesis Formulation of submicroscopical particles from branched oligoesters The aim of the thesis was directed to the nanoparticles preparation and optimization method. As the carriers were used oligoesters and polyesters of aliphatic alpha hydroxyacids with branched constutution of chain. Emulsion method solvent distribution and evaporation was used as preparation procedure. The process of oil phase dispersion in the aqueous one was modified in the aspect of velocity of the pouring of this phase into water and in the aspect of continuity of the process. Various solvents of carriers were tested, as emulsifiers were used lecithins and pure phophatidylcholine with the possibility of localisation of these emulsifiers into outer phase or into both the immiscible phases at the same time. The actual acidity change of outer phase by alcalisation was evaluated also. It was demonstrated effect of molecular parameters of carrier, effect of solvent quality and the type of emulsifier and its situation in the heterogeneous system, and effect of modification of the dispersion process on size parameters and on zeta potential of...
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Acyclovir release from plasticized oligoesters
Hlavsová, Lucie ; Šnejdrová, Eva (advisor) ; Dittrich, Milan (referee)
Hlavsová Lucie: Acyclovir release from plasticized oligoesters. Diploma thesis. Faculty of Pharmacy in Hradec Králové, 2008. Summary The aim of this work was the study of the Acyclovir release from oligoester carriers branched with various concentration of either mannitol (3M, 5M, 8M) or dipentaerythritol (3D, 5D, 8D) and plasticized with 30 % triethyl citrate (TEC) or 20 % ethyl pyruvate (EP). Theoretical part is occupied with physical-chemical properties of the lactic-glycolic polyesters, biodegradation and formation of the stereo complexes. It is also directed at the herpetic viruses, properties of ACV and other virostatics. The 150,0 mg matrices composed of carrier, Acyclovir of 4% and plasticizer either TEC of 30% or EP of 20% were prepared. They were put to the static dissolution test using phosphate citrate buffer pH 6,0 at 37řC. The ACV released was determined spectrophotometricaly at 256 nm. The best release behaviour was found at the carrier 3M with the linear ACV released during 20 day. Significant acceleration at the 6th hour going on to the 1st day was observed.
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