采用挤出- 滚圆法制备盐酸文拉法辛丸芯，并以单因素试验和Box-Behnken 设计优化处方及工艺参数。所得最佳工艺为：挤出速度35 r/min、润湿剂用量25％、滚圆速度1 050 r/min、滚圆时间8 min。按此工艺制得的含药丸芯收率及圆整度实测值均与模型预测值较接近。采用流化床包衣法对所得含药丸芯包隔离衣层及缓释衣层，填充入胶囊后得到仅需日服1 次的水溶性药物缓释制剂。以市售缓释胶囊( 怡诺思) 作参比制剂进行体外释放度考察，结果3 批自制品与参比制剂释放曲线的相似因子(f2) 均大于50，提示两种制剂的体外释放行为基本一致。

The pellet cores loaded with venlafaxine hydrochloride were prepared by extrusion-spheronization technique. The formulation and process parameters were optimized with single factor test and Box-Behnken design. The optimal process was as follows: extrusion speed was 35 r/min, the amount of wetting agent was 25％, spheronization speed was 1 050 r/min and the spheronization time was 8 min. The measured values of yield and roundness for the drugloading pellet cores prepared by the optimal process were close to the model predicted values. The isolation layer and sustained-release layer were coated on the above pellet cores by fluid bed coating process. Then the obtained particles were filled into capsules to get a sustained-release formulation taken only once a day for water-soluble drug. The in vitro
release was carried out with the commercial sustained-release capsules (Effexor XR®) as a reference preparation. The results showed that the release profiles of three self-made products were all consistent with the reference preparation according to the similarity factor (f2) values which were all over 50.