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Open access

Dana Sabadková, Aleš Franc, Jan Muselík and David Neumann

Abstract

Patients tend to prevent hypoglycemia by excessive saccharide intake leading to poorer glycemic control with potentially fatal consequences. This problem could be resolved by means of pellets with glucose release delayed by 120–360 min as a compensation of the antidiabetic drug peak effect. No glucose is released before; hence there is no risk of hyperglycemia and secondary complications. The pellets contain glucose in combination with an osmotically active ingredient and are coated with an ethylcellulose dispersion, which forms an insoluble semipermeable membrane and ensures delayed release. The release of glucose was assessed using dissolution and high-performance liquid chromatography. Dissolution profiles indicated the possibility of achieving the requested lag time using a combination of adequate compositions and coating concentrations. Lag times of 60, 240 and 360 min were achieved. The sample containing carboxymethyl starch was found to be most suitable for the intent of this work.

Open access

Aleš Franc, Jan Muselłk, Roman Goněc and David Vetchý

Abstract

Substances in the form of weak acid salts have been found to be problematic for dissolution testing. Their absorption can start only after they are turned into the form of an acid following the gastric passage although they were administered in the form of a salt. Due to poor solubility, they cannot be tested in acidic gastric environment for a biased dissolution profile. The biphasic dissolution method is promising for overcoming this obstacle. Tablets with warfarin clathrate sodium salt in two concentrations and two different particle size distributions were tested as a suitable model for finding the medium and process conditions of dissolution. The dissolution method based on the use of the upper organic layer (1-octanol) and the lower aqueous layer 0.1 mol L−1 HCl) was found suitable and discriminatory for tablets containing active substances in the form of salts of weak acids. The method also reflects physical differences in the quality of used substances.

Open access

Aleš Franc, Slavomir Kurhajec, Sylvie Pavloková, Dana Sabadková and Jan Muselík

Abstract

The aim of this study was to find the optimal tablet composition with maximum content of dried fruits (Cornus mas L.). The effect of three different concentrations (12.5, 25 and 50 %) of two types of microcrystalline cellulose (Avicel® PH 101 and Avicel® PH 200) and three different compression pressures (20, 60 and 100 MPa) on the physical properties of tablet blends and tablets was studied. Tablets containing 50 % Avicel® PH 101 compressed under 100 MPa were found to have the best physical properties. This combination of composition and compression pressure resulted in stable tablets even after storage under accelerated stability conditions (6 months, 40 °C and 75 % RH).

Open access

Jan Muselík, Aleš Franc, Petr Doležel, Roman Goněc, Anna Krondlová and Ivana Lukášová

Abstract

The article describes the development and production of tablets using direct compression of powder mixtures. The aim was to describe the impact of filler particle size and the time of lubricant addition during mixing on content uniformity according to the Good Manufacturing Practice (GMP) process validation requirements. Processes are regulated by complex directives, forcing the producers to validate, using sophisticated methods, the content uniformity of intermediates as well as final products. Cutting down of production time and material, shortening of analyses, and fast and reliable statistic evaluation of results can reduce the final price without affecting product quality. The manufacturing process of directly compressed tablets containing the low dose active pharmaceutical ingredient (API) warfarin, with content uniformity passing validation criteria, is used as a model example. Statistic methods have proved that the manufacturing process is reproducible. Methods suitable for elucidation of various properties of the final blend, e.g., measurement of electrostatic charge by Faraday pail and evaluation of mutual influences of researched variables by partial least square (PLS) regression, were used. Using these methods, it was proved that the filler with higher particle size increased the content uniformity of both blends and the ensuing tablets. Addition of the lubricant, magnesium stearate, during the blending process improved the content uniformity of blends containing the filler with larger particles. This seems to be caused by reduced sampling error due to the suppression of electrostatic charge.

Open access

Franc Janžekovič, Franc Bračko, Aleš Tomažič, Tina Klenovšek and Nastja Mencinger

Abstract

The article presents dietary habits of the Peregrine Falcon in the urban environment of Maribor. The diet was studied with an analysis of prey remnants at the nesting site. In October 2015, prey remnants were collected after the nesting in and around the nest built on top of the grain storage silo. Prey remnants, mostly bones and feathers, were sorted into body parts: skull with the beak, wings, and legs. Wings were the most numerous remnants with 41.7%, followed by legs and skulls with 28.1% each. In total, 96 units of prey were found, belonging to five different species of birds. The number of specimens and biomass was dominated by Feral Pigeons Columba livia domestica with 64.6% in number and 89.5% in prey biomass. The second most frequent prey of falcons were Starlings Sturnus vulgaris.