Priese Florian, Frisch Toni, Wolf Bertram
Department of Applied Biosciences and Process Engineering, Anhalt University of Applied Sciences , Bernburg , Germany.
Pharm Dev Technol. 2015 Jun;20(4):417-25. doi: 10.3109/10837450.2013.879883. Epub 2014 Feb 3.
In order to investigate the influence of coatings for controlled active pharmaceutical ingredient (API) release, two types of pellets were used. Microcrystalline pellets were coated with a model API using the Wurster fluidized bed technique in laboratory scale (layered Cellets). Another type of pellets consisting of microcrystalline cellulose and model API was manufactured by fluidized bed rotor pelletization (matrix pellets (MP)). Both kinds of pellets were coated in a Wurster fluidized bed process with a polymer mixture of ethylcellulose to achieve retarded API release. With layered Cellets and an increased thickness of the ethylcellulose layer, the lag-time was increased and the release rate was decreased. In the case of MP, retardation was less pronounced probable due to inhomogeneous polymer film formation as a result of the porous particle surface. To reduce the surface roughness, the MP were coated with polyvinylpyrrolidone (PVP) as an intermediate smoothing layer, in a first trial step by step. In a second trial, pelletization and the coating steps were performed in an uninterrupted process. Intermediate PVP coating improved the ethylcellulose film formation and led to a more pronounced retardation of API release. The uninterrupted process of matrix pellet manufacturing and coating results in a product with only low retarded release.
为了研究包衣对活性药物成分（API）控释的影响，使用了两种类型的微丸。在实验室规模下，采用Wurster流化床技术用模型API对微晶微丸进行包衣（层状微丸）。另一种由微晶纤维素和模型API组成的微丸通过流化床旋转制丸法制备（基质微丸（MP））。两种微丸均在Wurster流化床工艺中用乙基纤维素聚合物混合物进行包衣，以实现API的缓释。对于层状微丸，随着乙基纤维素层厚度的增加，滞后时间延长，释放速率降低。对于MP，由于多孔颗粒表面导致聚合物膜形成不均匀，缓释效果不太明显。为了降低表面粗糙度，在第一个试验步骤中，逐步用聚乙烯吡咯烷酮（PVP）作为中间平滑层对MP进行包衣。在第二个试验中，制丸和包衣步骤在一个不间断的过程中进行。中间PVP包衣改善了乙基纤维素膜的形成，并导致API释放的缓释效果更明显。基质微丸制造和包衣的不间断过程导致产品的缓释效果较低。
