Design space for a solventless photocurable pharmaceutical coating

Solventless coating technologies can overcome many of the disadvantages associated with using solvents in pharmaceutical coating. A solventless photocurable film-coating system was investigated in which liquid photocurable prepolymer and powdered pore-forming agents were applied onto non-parell beads in a mini-coating pan. The beads were exposed to light after each coating layer. Using lactose as a filler, an optimum range of filler to photocurable polymer ratio was 1.8 to 3.0 to achieve good process efficiency and uniformity. The ratio was sensitive to particle size and filler type. The initiator concentration and light intensity also were evaluated. The time required to coat a batch was dramatically reduced compared with conventional film coating. © 2006 ISPE. All rights reserved.