Preparation and optimization of formulation for lappaconitine hydrobromide push-pull osmotic pump controlled release tablets / 第二军医大学学报

ABSTRACT

Objective To prepare lappaconitine hydrobromide push-pull osmotic pump controlled release tablets and screen for the optimal formulation. Methods The percent of cumulative release was used as the evaluation index for the drug release profile in vitro. The effects of PEO N750, PEO WSR303, and plasticizer amounts and coating weight gain on the releasing behavior were investigated through single-factor method. Based on single-factor study on the compositions, the optimal formulation for lappaconitine hydrobromide push-pull osmotic pump controlled release tablet was selected via orthogonal design. The in vitro release of the optimized formulation was also fitted to different models. Results The results of orthogonal design indicated that coating weight gain had a significant effect on the drug release in vitro —<0. 05). The optimal formula was as follows; lappaconitine hydrobromide 20 mg, PEO N750 160 mg, NaCl 30 mg in drug layer; PEO WSR303 75 mg, NaCl 20 mg in the push layer; and plasticizer PEG 4000 was 10% and weight gain was 5% in the coating composition The release rate of the tablets with optimized formulation was constant within 12 h, and the cumulative release could reach 95. 02 %. Conclusion The current method to prepare lappaconitine hydrobromide push-pull osmotic pump controlled release tablets is stable, and the in vitro drug release has an excellent zero-release profile within 12 h (r=0. 992 1), which meets the standard for controlled release.