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Purpose: Controlled-release pharmaceuticals have been usually manufactured by wet spray-coating processes with various types of fluidized bed coaters.These spray-coating processes are known to be time and energy-consuming.Therefore, dry coating process was investigated as a method of solving the problems encountered in the spray processes.Methods: A dry powder process was carried out using an elliptical-rotor type of high-speed powder mixer.A pulverized lauric acid powder (LA, mp.44℃) was first layered on 177-210 μm core-particles of crystalline cellulose.Next, a micronized drug powder (CCSS, water-soluble carbazochrome sodium sulfonate, 5.5 μm) was layered on the LA-layered core-particles and, subsequently, newly designed poly(ethyl acrylate/methyl methacrylate/2-hydroxyethyl methacrylate) powder was coated.Results: The maximum core-charging, the stepwise addition of fine powder in a small amount and the stepwise elevation of the rotational speed of rotor 1ed to improvement of process performance.When the polymer suspensions synthesized by emulsion polymerization were freeze-dried after salting out, the products were obtained as lightly agglomerated powder of the polymeric nanoparticles.Use of these nano-powders led to a high efficiency in the dry powder coating process.The prolonged release of drug from 6∶12∶9 poly(EA/MMA/HEMA)-coated microcapsules was achieved by curing at 60℃.The established technique was also applied to continuous mass production with a specially designed twin axial kneader.The precise temperature control led to a high performance of dry powder coating process.Conclusion: These studies have demonstrated that use of well designed nano-powders leads to success in the dry powder coating process.