Akande O F, Ford J L, Rowe P H, Rubinstein M H
Drug Delivery and Pharmaceutical Technology Group, School of Pharmacy and Chemistry, Liverpool John Moores University, UK.
J Pharm Pharmacol. 1998 Jan;50(1):19-28. doi: 10.1111/j.2042-7158.1998.tb03300.x.
The effects of lag-time and dwell-time on the compaction properties of tablets compressed from a 1:1 blend of paracetamol and microcrystalline cellulose have been examined using a compaction simulator. Increases in lag-times (from 0.06 to 0.53 s) resulted in small increases in the tensile strengths of the tablets when combinations of 80 and 160 MPa were used as the compression pressures. Further increases in lag-time did not alter the tablet strengths. When combinations of 240 and 320 MPa were used for pre-compression and main compression, the effects on the tensile strengths were more complex, partly because the high elastic recoveries of the tablets resulted in greater variability in the data. Increases in lag-times from 0.06 to 0.97 s resulted in an increase of between 12 and 28% in tensile strength. Longer lag-times (1.24 or 1.52 s) did not result in further increases in tensile strength. The application of a dwell-time of 0.26 s during pre-compression or main compression pressures of 80 and 160 MPa generally led to a decrease (14-22%) in tensile strength compared with tablets where no dwell-time was used. This was because of increases in both the elastic recoveries and elastic energies. Subsequent increases in dwell-time from 0.26 to 0.9 s resulted in increases in tablet strength compared with that obtained when no dwell-time was applied. The tensile strengths of tablets made with a pre-compression of 160 MPa then a main compression of 80 MPa were 11-33% higher than those of tablets made with a pre-compression of 80 MPa then a main compression of 160 MPa. This was because higher plastic energies and more plastic deformation occurred at the higher pre-compression. Generally, the application of dwell-time resulted in greater increases in tensile strengths than lag-time, which had less effect on the compaction properties.
使用压片模拟器研究了延迟时间和保压时间对由对乙酰氨基酚和微晶纤维素1:1混合物压制而成片剂的压实特性的影响。当使用80和160 MPa的组合作为压缩压力时，延迟时间增加（从0.06秒增加到0.53秒）会导致片剂的抗张强度略有增加。延迟时间的进一步增加并未改变片剂强度。当使用240和320 MPa的组合进行预压和主压时，对抗张强度的影响更为复杂，部分原因是片剂的高弹性回复导致数据的变异性更大。延迟时间从0.06秒增加到0.97秒导致抗张强度增加了12%至28%。更长的延迟时间（1.24或1.52秒）并未导致抗张强度进一步增加。在80和160 MPa的预压或主压过程中施加0.26秒的保压时间，与未使用保压时间的片剂相比，通常会导致抗张强度降低（14%-22%）。这是因为弹性回复和弹性能量都增加了。随后保压时间从0.26秒增加到0.9秒，与未施加保压时间时相比，片剂强度增加。先进行160 MPa预压然后80 MPa主压制成的片剂的抗张强度比先进行80 MPa预压然后160 MPa主压制成的片剂高11%-33%。这是因为在较高的预压下发生了更高的塑性能量和更多的塑性变形。一般来说，保压时间的应用导致抗张强度的增加比延迟时间更大，延迟时间对压实特性的影响较小。
