Реологические исследования мягких лекарственных средств

Abstract

Исследованы реологические свойства мягких лекарственных средств, изготовленных на разных основах- носителях. Для каждой мягкой лекарственной формы установлены пределы текучести, исследовано изменение структурной вязкости в зависимости от скорости сдвига, определены площади петель гистерезиса, значение которых характеризует механическую устойчивость структурированных систем, установлена степень тиксотропии.

RHEOLOGICAL STUDIES OF SEMISOLID MEDICINES Rheological study of semi-solid dosage forms are required during the design composition, that allows to estimate the influence of excipients and their concentration on the visco-plastic properties, as well as to determine the technological parameters of the production process. Material and methods. The objects of the rheological properties study of of semi-solid dosage forms were used ointment “Levomekol”, ointment “Espoli”, liniment “Chloromycetin”, gel “Troxerutin” made on various suitable vehicles of active substances. Rheological properties (structural and mechanical) were studied by using rheoviscosimeter «Rheolab QC» (Anton Paar, Austria) at 20°C. Results and discussion. The results of the data were plotted transverse strain versus shear rate, which allows us to estimate the visco – plastic properties of semi-solid dosage forms, the type of flow and thixotropic properties that shows the mechanical stability of structured systems. For each semi-solid dosage form was determined liquid limit, defined the square of the hysteretic loops. From tabular and graphical data presents the variation of plastic viscosity on the shear rate in the forward (shear rate increases) and reverse way (shear rate decreases). Conclusions. The studies assist to assess the visco-plastic properties of semi-solid dosage forms in the development phase for prediction their stability, extrusion capacity and consumer properties.