Particulate medicated systems

Univerzita Karlova Farmaceutická fakulta v Hradci Králové Katedra farmaceutické technologie Školitel: doc. RNDr. Milan Dittrich, CSc. Student: Josef Mašek Název diplomové práce: Částicové medikované systémy Diplomová práce byla zaměřena na experimentální studium vlivu technologických parametrů na charakteristiku nanočástic z terpolymeru alifatických hydroxykyselin s tripentaerythritolem. V teoretické části je pozornost věnována pojednání o nanočásticích jako systémech pro cílenou distribuci léčiv a metodám jejich přípravy, o mikroenkapsulačních technikách, o targetingu a také o základních parametrech nanočástic, jejich velikosti a zeta potenciálu. Zaměření experimentů se týkalo vlivu některých formulačních faktorů, jako tenzidu, koncentrace léčivé látky a polymerního nosiče na velikost a polydisperzitu nanočástic, jejich zeta potenciál a enkapsulační efektivitu. Byl prokázán vliv složení tenzidu na vznik a parametry nanočástic. Pro další postup se osvědčil methylsulfonylmethan jako vhodné netoxické rozpouštědlo v kompozicích biodegradabilních polymerů.Charles University Faculty of Pharmacy in Hradec Králové Department of Pharmaceutical Technology Consultant: doc. RNDr. Milan Dittrich, CSc. Student: Josef Mašek Title of Thesis: Particulate medicated systems This diploma thesis was focused on experimetal study of influence of technological parameters on the characteristics of nanoparticles made of terpolymer of aliphatic hydroxy acids with tripentaerythritol. In the theoretical part of this thesis nanoparticles as a system for targeted drug distribution were described. Methods of preparation of these nanoparticles, microencapsulation techniques, targeting, basic parameters of the nanoparticles, their size and zeta potential were mentioned in the theoretical part. The experiments were focused on influence of formulation factors, as detergent, concentration of the drug and polymer device on polydispersity of the nanoparticles, their zeta potential and encapsulation effectivity. The influence of detergent formulation on formation and parameters of the nanoparticles was proved. Methylsulfonylmethan was proved for the next experimental procedure as a suitable non-toxic solvent in compositions of biodegradable polymers.Katedra farmaceutické technologieDepartment of Pharmaceutical TechnologyFaculty of Pharmacy in Hradec KrálovéFarmaceutická fakulta v Hradci Králov

Adaptive discretization refinement for discrete models of coupled mechanics and mass transport in concrete

An adaptive discretization refinement strategy for steady state discrete mesoscale models of coupled mechanics and mass transport in concrete is presented. Coupling is provided by two phenomena: the Biot's theory of poromechanics and an effect of cracks on material permeability coefficient. The model kinematics is derived from rigid body motion of Voronoi cells obtained by tessellation of the domain. Starting with a coarse discretization, the density of Voronoi generator points is adaptively increased on the fly in regions where the maximum principal stress exceeds a chosen threshold. Purely elastic behavior is assumed in the coarse discretization, therefore no transfer of history/state variables is needed. Examples showing (i) computational time savings achieved via the adaptive technique and (ii) an agreement of the outputs from the fine and adaptive models during simulations of hydraulic fracturing and three-point bending combined with a fluid pressure loading are presented.Comment: 25 pages, 13 figure

Nanofibers in Mucosal Drug and Vaccine Delivery

Successful mucosal administration and delivery of drugs still pose a great challenge. However, the possibility to deliver not only small drug molecules but also macromolecular drugs and nanoparticles via mucosal surfaces represents a great opportunity. Rapid onset of drug action, avoidance of first-pass metabolism, and high immunocompetence of mucosa are some of the important features for mucosal drug and vaccine delivery. The use of mucoadhesive drug delivery systems, systems with fast dissolving properties, and nanomaterials with mucus penetration properties are examples of successful strategies to achieve effective mucosal drug and vaccine delivery. Non-keratinized mucosa of the oral cavity, the nasal and vaginal mucosa represent favorable sites of drug administration. Polymer nanofibers have attracted much attention because of remarkable characteristics such as a large surface area to volume ratio and high porosity. Nanofibers have been extensively used for different biomedical applications including wound dressing, tissue engineering, and drug delivery. Among their fabrication methods, the introduction of electrospinning technique was an important step toward achieving the goal of large scale industrial production of nanofiber-based drug delivery systems used in mucosal applications. This chapter provides an overview on all aspects of mucosal drug and vaccine delivery using nanofibers

Upgrade of The Langendorff Apparatus Using The Infrared Thermo-Control System and An Intelligent Heater

Biological experiments involving isolated organs and tissues demand precise temperature monitoring and regulation. An automatic temperature control system was proposed and optimised on real isolated swine hearts and the prototype is described in this work. The traditional Langendorff apparatus consists of a heart holder, a reservoir of perfusion solution flowing to aortic cannula and a heating bath allowing passive heat transfer to the reservoir of perfusion solution. The commercial infrared camera FLIR T62101 was added to this basic set-up and used for very precise monitoring of the temperature kinetic of the organ and connected with an electronic feedback loop, which allowed real-time and precise regulation of heat transfer from the heating bath to the perfusion solution and in turn indirectly to the heart tissue. This provides real time control and active regulation of the myocardial tissue temperature. The infrared camera was tested in several modes and several variants of detection were optimised for ideal measurement of the region of interest of the ex vivo organ. The kinetics of the temperature changes and temperature stability of the tissue were recorded and calibrated by external electronic thermometers (type Pt100, inserted in tissue). The time lapse from the hang-up of the hypo termed organ (30 °C) until optimal warming (37 °C) was less than eight minutes in the final instrument prototype. The final stability of the 37 °C tissue temperature was approved; the temperature fluctuation of left ventricle tissue was characterised as 36.8 ± 0.5 °C. This upgraded traditional instrument could be used in specific preclinical and clinical transplantation and analytical projects in future

The influence of different formulations and process parameters during the preparation of drug-loaded PLGA microspheres evaluated by multivariate data analysis

The main objective of this study was to evaluate the influence of the formulation and process parameters on PLGA microparticles containing a practically insoluble model drug (ibuprofen) prepared by the o/w solvent evaporation method. Multivariate data analysis was used. The effects of altered stirring speed of a mechanical stirrer (600, 1000 rpm), emulsifier concentrations (PVA concentration 0.1 %, 1 %) and solvent selection (dichlormethane, ethyl acetate) on microparticles characteristics (encapsulation efficiency, drug loading, burst effect) were observed. It was found that with increased stirring speed, the PVA concentration or the use of ethyl acetate had a significantly negative effect on encapsulation efficiency. In addition, ethyl acetate had an adverse effect on the burst effect, while the increased stirring speed had the opposite effect. Drug load was not affected by any individual variable, but rather by the interactions of evaluated variables

The Contemporary Managemen of Secondary Schools in the Pilsen Region from a Gender Perspective

Centrum školského managementuPedagogická fakultaFaculty of Educatio