(311b) Improvement in Flowability and Bulk Density of Pharmaceutical Powders Thorough Surface Modification

The cohesive nature of Active Pharmaceutical Ingredients (API) gives rise to operational problems such as feeding, blending, tabletting etc, which ultimately influences the product uniformity and performance of the drug product. To reduce cohesive properties, surface of three API powders (Acetaminophen, Micronized Acetaminophen, and Ibuprofen) was modified by dry coating of nano-size silica using the Magnetic Assisted Impaction Coater (MAIC). A complete Design of Experiment (DOE) was performed to establish a standard operating protocol for the dry coating of API. To quantify the flow improvement, the Angle of repose (AOR) of the as received powders and the surface modified powders was measured using the Hosokawa Powder Tester. Powder characteristics like the bulk density, flow function coefficient (FFC), compressibility and aerability were measured for same powders using the Freeman Powder Rheometer (FT4). The results show substantial improvement of bulk density, FFC and compressibility of surface modified APIs with respect to as received APIs. The results also indicate that surface modification of APIs by dry coating is a very useful tool for the improvement of key powder properties like flowability, bulk density etc. that are due to powder cohesion. To illustrate the main impact of surface modification, a phase diagram is proposed that classifies powders based on flowability based on the FFC and bulk density indicating improvements in handling as well as packing tendency.