Protective coating of highly porous alginate aerogel particles in a Wurster fluidized bed

Abstract

Alginate aerogel particles were successfully coated with a copovidone and hydroxypropyl cellulose based polymer in a Wurster fluidized bed. The results indicate that the pores of aerogels were not damaged during the process. Several sets of experiments were conducted at three different temperatures and atomizing air pressures. Coating time for all the runs ranged from 5 min to 40 min and the coating thickness ranged from 12.4 +/- 4.6 mu m to 170.6 +/- 43.3 mu m.Changing bed temperature led to significant changes in coating thickness whereas both bed temperature and atomizing pressure affected coating layer surface morphology. The smoothest coating layer surface and the highest coating efficiency which was 69.2 +/- 0.4% were achieved at 50 degrees C with 1.7 bar atomizing pressure. At this condition, the coating layer thickness increased linearly with coating time.(c) 2022 Elsevier B.V. All rights reserved.