Tablet Coating Lecture Flashcards
Wurster Fluid Bed Process
Tablets are placed into a vertical cylinder that suspended in column of air supplied from the bottom
Tablet rotates vertically and horizontally
Coating is applied from the bottom
Top Spray coating
Sprayed downward onto the particles
Tangential spray coating
Spray nozzle is arranged tangentially to the rotor
Compression coating
Compressed onto a core of drug with a special press
More uniform and less material –> lighter, smaller, less expensive tablets
Blistering
Coated tablets are over dried because of quick evaporation
Orange-peeling
Uneven spread causes a bumpy or orange peel effect
Sticking and picking
Occurs due to excessive wetting of the tablets sticking to each other (multiple pills)
Mottling
Unequal or uneven distribution of color
Bridgin
Film shrinks and pulls away from sharp corners of bisect, producing a briding on surface depression
Filling
Too much coating solution or a thick coating is applied and engravings are filled
Film Peeling
Cohesiveness of a coating fails and peels back from the surface
Cracking
Swell of the core causes cracking
Edge wearing
Fracture on the tablet edges
Marbling
Collection of wax in the small surface depression of a rough coating
Twinning
One tablet sticks to another
