کد مقاله | کد نشریه | سال انتشار | مقاله انگلیسی | نسخه تمام متن |
---|---|---|---|---|
238037 | 465738 | 2009 | 9 صفحه PDF | دانلود رایگان |
We study the relation between flow and electrical conductivity of multiple formulations of pharmaceutical powder blends. Ten formulations were tested, consisting of two excipient sets, two active preparations, and a variety of food-grade additives including magnesium stearate (MgSt), and ionic and conductive materials such as ascorbic acid, talc, sodium carbonate, colloidal silica and TiO2. Electrical impedance, flow index and dilation were independently measured for all of the blends, and a strong correlation was found between every pair of these three properties. The relation between flow and dilation has been observed before; we find for the first time that there is an exponential relationship between flow index or dilation and impedance. This indicates that cohesive powder behavior depends on powder electrical properties, raising the questions of whether additives such as MgSt affect friction and conductivity per se and what mechanism and phenomenon links cohesion and conductivity.
We study the relation between flow and electrical conductivity of multiple formulations of pharmaceutical powder blends. Ten formulations were tested, consisting of two excipient sets, two active preparations, and a variety of food-grade additives including magnesium stearate (MgSt), and ionic and conductive materials such as ascorbic acid, talc, sodium carbonate, colloidal silica and TiO2. Electrical impedance, flow index and dilation were independently measured for all of the blends, and a strong correlation was found between every pair of these three properties. The relation between flow and dilation has been observed before; we find for the first time that there is an exponential relationship between flow index or dilation and impedance. This indicates that cohesive powder behavior depends on powder electrical properties, raising the questions of whether additives such as MgSt affect friction and conductivity per se and what mechanism and phenomenon links cohesion and conductivity.Figure optionsDownload as PowerPoint slide
Journal: Powder Technology - Volume 192, Issue 2, 5 June 2009, Pages 157–165