title: Analysis of the Particle Formation Process of Structured Microparticles.
abstract: The particle formation process for microparticles of cellulose acetate butyrate dried from an acetone solution was investigated experimentally and theoretically. A monodisperse droplet chain was used to produce solution microdroplets in a size range of 55-70 μm with solution concentrations of 0.37 and 10 mg/mL. As the droplets dried in a laminar air flow with a temperature of 30, 40, or 55 °C, the particle formation process was recorded by two independent optical methods. Dried particles in a size range of 10-30 μm were collected for morphology analysis, showing hollow, elongated particles whose structure was dependent on the drying gas temperature and initial solution concentration. The setup allowed comprehensive measurements of the particle formation process to be made, including the period after initial shell formation. The early particle formation process for this system was controlled by the diffusion of cellulose acetate butyrate in the liquid phase, whereas later stages of the process were dominated by shell buckling and folding.
authors: Department of Mechanical Engineering, University of Alberta, 4-9 Mechanical Engineering Building, Edmonton, AB, T6G 2G8, Canada.
authors: Alberto
authors: A
authors: Baldelli
authors: Department of Mechanical Engineering, University of Alberta, 4-9 Mechanical Engineering Building, Edmonton, AB, T6G 2G8, Canada.
authors: Mohammed A
authors: MA
authors: Boraey
authors: Department of Mechanical Engineering, University of Alberta, 4-9 Mechanical Engineering Building, Edmonton, AB, T6G 2G8, Canada.
authors: David S
authors: DS
authors: Nobes
authors: Department of Mechanical Engineering, University of Alberta, 4-9 Mechanical Engineering Building, Edmonton, AB, T6G 2G8, Canada.
authors: Reinhard
authors: R
authors: Vehring
mesh_terms: D002482:Cellulose / Q000031:analogs & derivatives / Q000737:chemistry; D002626:Chemistry, Pharmaceutical / Q000295:instrumentation / Q000379:methods*; D003890:Desiccation; D004339:Drug Compounding / Q000379:methods; D016503:Drug Delivery Systems; D058995:Dry Powder Inhalers; D008863:Microspheres; D053758:Nanoparticles / Q000737:chemistry*; D010316:Particle Size; D013499:Surface Properties; D013696:Temperature
chemical_list: D002482:Cellulose; C014396:cellulose acetate-butyrate
keywords: cellulose acetate butyrate; drug delivery; evaporation process; particle engineering; particle formation; structured microparticles