The combined use of imaging approaches to assess drug release from multicomponent solid dispersions

PURPOSE: Imaging methods were used as tools to provide an understanding of phenomena that occur during dissolution experiments, and ultimately to select the best ratio of two polymers in a matrix in terms of enhancement of the dissolution rate and prevention of crystallization during dissolution. METHODS: Magnetic resonance imaging, ATR-FTIR spectroscopic imaging and Raman mapping have been used to study the release mechanism of a poorly water soluble drug, aprepitant, from multicomponent amorphous solid dispersions. Solid dispersions were prepared based on the combination of two selected polymers - Soluplus, as a solubilizer, and PVP, as a dissolution enhancer. Formulations were prepared in a ratio of Soluplus:PVP 1:10, 1:5, 1:3, and 1:1, in order to obtain favorable properties of the polymer carrier. RESULTS: The crystallization of aprepitant during dissolution has occurred to a varying degree in the polymer ratios 1:10, 1:5, and 1:3, but the increasing presence of Soluplus in the formulation delayed the onset of crystallization. The Soluplus:PVP 1:1 solid dispersion proved to be the best matrix studied, combining the abilities of both polymers in a synergistic manner. CONCLUSIONS: Aprepitant dissolution rate has been significantly enhanced. This study highlights the benefits of combining imaging methods in order to understand the release process

Advanced surface chemical analysis of continuously manufactured drug loaded composite pellets

The aim of the present study was to develop and characterise polymeric composite pellets by means of continuous melt extrusion techniques. Powder blends of a steroid hormone (SH) as a model drug and either ethyl cellulose (EC N10 and EC P7 grades) or hydroxypropyl methylcellulose (HPMC AS grade) as polymeric carrier were extruded using a Pharma 11 mm twin screw extruder in a continuous mode of operation to manufacture extruded composite pellets of 1 mm length. Molecular modelling study using commercial Gaussian 09 software outlined a possible drug-polymer interaction in the molecular level to develop solid dispersions of the drug in the pellets. Solid-state analysis conducted via a differential scanning calorimetry (DSC), hot stage microscopy (HSM) and X-ray powder diffraction (XRPD) analyses revealed the amorphous state of the drug in the polymer matrices. Surface analysis using SEM/energy dispersive X-ray (EDX) of the produced pellets arguably showed a homogenous distribution of the C and O atoms in the pellet matrices. Moreover, advanced chemical surface analysis conducted via atomic force microscopy (AFM) showed a homogenous phase system having the drug molecule dispersed onto the amorphous matrices while Raman mapping confirmed the homogenous single-phase drug distribution in the manufactured composite pellets. Such composite pellets are expected to deliver multidisciplinary applications in drug delivery and medical sciences by e.g. modifying drug solubility/dissolutions or stabilizing the unstable drug (e.g. hormone, protein) in the composite network

Importance of alternative punishmentins in Czech Republic

Tato bakalářská práce se zabývá tématem alternativní tresty v České republice. Je především zaměřena na trest obecně prospěšné práce. Cílem je zjistit jak trest funguje v praxi ve vybrané oblasti a zda mají obecně prospěšné práce pro městské úřady v Praze nějaký význam. V úvodní kapitole se chci zaměřit na obecnou charakteristiku alternativní trestů. Další bod je zasvěcen obecně prospěšným pracím a jejich problematice. Ve třetí části bych ráda představila instituci Probační a mediační služby ČR a ukázala jejich očekávání. Tato instituce apeluje na větší uplatňování alternativních trestů. Ve čtvrté kapitole se budu věnovat Magistrátu hlavního města Prahy a informacím, které mi magistrát poskytne. Tyto údaje porovnám s daty poskytnutými výše zmíněnou institucí.This bachelor thesis deals with subject of alternative punishments in the Czech Republic. It is primarily focused on punishment of the common beneficial work. The aim is to find out how the punishment works in practice in selected areas and whether the common beneficial works in the municipal office in Prague have some significance. In the introductory chapter I want to focus on general characteristics of alternative punishments. Another section is devoted to common beneficial works and their problems. In the third part I would like to introduce the institution of the Probation and Mediation Service of the Czech Republic and show it`s expectations. This institution calls for greater application of alternative punishments. In the fourth chapter I will deal with the Prague City Hall and the information that the municipality provide. These figures I will compare with the data provided by the aforementioned institution

Importance of alternative punishmentins in Czech Republic

This bachelor thesis deals with subject of alternative punishments in the Czech Republic. It is primarily focused on punishment of the common beneficial work. The aim is to find out how the punishment works in practice in selected areas and whether the common beneficial works in the municipal office in Prague have some significance. In the introductory chapter I want to focus on general characteristics of alternative punishments. Another section is devoted to common beneficial works and their problems. In the third part I would like to introduce the institution of the Probation and Mediation Service of the Czech Republic and show it`s expectations. This institution calls for greater application of alternative punishments. In the fourth chapter I will deal with the Prague City Hall and the information that the municipality provide. These figures I will compare with the data provided by the aforementioned institution