片剂成型对蒜酶稳定性的影响

Compression of influence of tablet compaction on the stability of alliinase

目的研究片剂成型对蒜酶稳定性的影响。方法以Heckel方程评价蒜酶的压缩成型性,研究成型过程中压力、填充剂、崩解剂及水分含量等因素对蒜酶活性的影响。结果蒜酶在压缩成型过程中主要发生弹性形变,可压性较差。蒜酶的活性开始随压力升高而降低,在720 Mpa时活性达到最低,继续增加压力后活性基本保持不变,表明压力可能是通过改变空间位阻使蒜酶的构象发生改变,进而影响其活性。填充剂和崩解剂均能缓解蒜酶活性的降低;一定的水分含量有助于蒜酶片剂的稳定。结论蒜酶压缩成型性较差且不稳定,塑性填充剂、崩解剂可改善其压缩行为,增强片剂的稳定性。

OBJECTIVE To investigate the influence of tablet compaction on the stability of alliinase in pharmaceutical formulations. METHODS The compression properties of alliinase powder were characterized by using Heckel equation. The influences of tableting factors including compaction pressures, fillers, disintegrating agents and humidity on the activity of alliinase were investigated. RESULTS Alliinase powder was found to be an elastic substance. The loss of activity of free enzyme was obvious even at the smallest tested compaction pressure,and there was a 50% activity loss at the pressure of 720 MPa. But when the pressure increased continually, the loss remained constant. The tablet porosity showed a parallet behavior with the alliinase which indicated that steric hindrance may result in the loss of activity. The extent of enzyme activity loss decreased with the addition of a plastic or a brittle excipient. It was also found that the tablet exhibited high activity in the presence of disintegrating agent. And leaving a small amount of water in tablet had positive influences on the activity of enzyme. CONCLUSION Alliinase presented poor compressibility and stability during compressing. This property could be improved when plastic fillers and disintegrating agents were used.