Year: 2006
Type: dissertation
Abstract: Approximately 80% of pharmaceutical products and the ingredients required for their manufacture are in powder form.The solid dosage form (tablets and capsules) is manufactured by either dry-blending of fine powder ingredients or combining the ingredients in a wet granulation step, followed by drying.Arching, ratholing, caking, segregation and flooding are some of the commonly encountered flow problems in the handling of fine powders.These problems lead to losses worth thousands of dollars at production scale.Poor powder flowability is a consequence of the combined effects of many variables, including improper equipment design, particle size, size distribution, shape, moisture content and surface texture.In the present work, a systematic study has been performed to determine the relationship between the flowability of fine powders and their physical properties of mean size and size distribution, density and shape.Flowability studies were done on six different powders: the NutraSweet® Brand sweetener (aspartame), Respitose ML001, Alpha-D-Lactose monohydrate, the pharmaceutical binder Methocel (R) F50 Premium Hydroxypropyl methylcellulose-HPMC, a placebo pharmaceutical granulate, and common pastry flour.Scanning electron microscopy (SEM) and stereomicroscopy were used for particle shape and size analysis.Particle size distribution was determined using the laser light scattering technique.Powder flowability was measured using shear strength, angle of repose, and tapped-to-bulk density measurements.A novel method of measuring the dynamic angle of repose using electrical capacitance tomography (ECT) was developed.Analysis of the images from microscopy revealed that the particles of aspartame and HPMC powders were elongated, the particles of ML001, pastry flour and lactose
Author: Abhaykumar Krishnarao Bodhmage
Language: English
Subfield: Computational Mechanics
Field: Engineering
Domain: Physical Sciences
Open Access status: green
OpenAlex ID: W71795287