ROTARY TANGENTIAL SPRAY TECHNIQUE FOR AQUEOUS FILM COATING OF INDOBUFEN PELLETS

Indobufen pellets, previously prepared by direct pelletization employi ng the rotary tangential spray fluidized bed (Rotoprocessor), were coa ted using the same equipment setup as for the film coating process. Di fferent amounts of the aqueous-based ethylcellulose dispersion (Aquaco at) were easily applied on the active cores of different compositions with no spray blocking or pellet sticking. The coating process was not influenced by changing the ethylcellulose (Aquacoat(R) ECD-30) formul ation with soft acrylic resin (Eudragit(R) NE 30D) or by adding water- soluble polymers (Pharmacoat(R) 606 and PEG 6000) to the coating dispe rsions. Simple setup, flexibility of operation, and short manufacturin g times were the advantageous features of the tangential spray equipme nt. These benefits were verified during the pellet coating process. Th e composition of the cores and membranes were confirmed as the determi ning parameters with respect to the performances in terms of the drug release rate. The morphological and functional results clearly demonst rated the tangential spray rotary system as a promising one-step techn ique for the preparation of indobufen prolonged-release multiple-unit dosage forms.