评价软胶囊中明胶交联反应的相关指标间的相关性及影响因素

Evaluation of correlation between gelatin crosslinking indicators and influence factors

目的 评价明胶交联反应指标间的相关性,考察影响软胶囊中明胶交联反应的因素,探讨软胶囊溶出迟缓机理。方法 采用甲醛处理软胶囊囊壳模拟交联反应,进行明胶溶胀动力学和溶出度实验,采用TNBS法测定ε氨基酸含量。应用差示热扫描分析明胶结构的变化。结果明胶交联后,平衡膨胀量(Seq)、百分溶出量和氨基酸含 量之间呈良好线性关系;平衡膨胀量、氨基酸含量与软胶囊崩解时间呈良好线性关系;在40℃或光照[(4500±500) lx]条件下放置的软胶囊囊壳的Seq显著低于室温避光下放置的软胶囊(P<0.01);甘氨酸和焦亚硫酸钠能有效阻止Seq的降低;明胶发生交联后,分子中螺旋 卷曲转变消失。结论明胶平衡膨胀量(Seq)、百分溶出量和氨基酸含量从 不同角度反映交联反应程度,有良好相关关系(r=0.9953-0.9985);高温、光线会促发明胶交联反应;抗氧剂能延缓交联反应的发生;明胶分子中螺旋 卷曲转变消失,水化作用减弱,是软胶囊溶出迟缓的主要原因。

Aim To evaluate the correlation between the swelling equilibrium quantity (S eq), dissolution rate and amino g roup content which were used to estimate the degree of gelatin crosslinking, and the factors which influence the crosslinking, and to investigate the crosslinki ng mechanism of delayed dissolution of soft capsules. Methods The swelling equilibrium quantity, dissolution rate and amino group content of formaldehyde-crosslinked capsule shells were determined . Gelatin structure was analyzed by means of DSC. Results A good lineal relativity was found between the swelling equilibrium quantity, dissolution rate and amino group content (r= 0.995 3- 0.998 5). The S eq of capsule shells was influenced by high te mperature, lighting and some additives. Glycine and sodium pyrosulfite might ret ard the decrease of S eq of capsule shells. Conclusion The swelling equilibrium quantity, dissolution rate and amino group content exhibited the same rule in gelatin crosslinking extent. High temperature, lighting and some additives might induce gelatin crosslinking. Antioxidant such as glycine and sodium pyrosulfite might retard the crosslinkin g.