Wolf B, Finke I
Sektion Biowissenschaften, Lehrstuhl Pharmazeutische Technologie der Universität, Leipzig.
Pharmazie. 1992 Feb;47(2):121-5.
In the case of ionic binding of drugs to bead cellulose and its derivatives there was no pronounced retardation obvious. Because of this lack benzocaine as a model drug was covalent bound to dialdehyde bead cellulose by an azomethine bond in analogy with enzyme immobilisation methods. The rate of liberation in phosphate buffer was low and incomplete compared with the dissolution rate of pure benzocaine under the same conditions. A further decrease of liberation rate was obtained by reduction of the azomethine to the amine bond. Retardation of drug liberation strictly speaking was not achieved. The main amount of liberated drug was liberated during the first 20 min, but after 6 h the rate was still under 50% of the drug available. The physical properties of the beads like spherical shape and porosity are not significantly influenced by oxidation of cellulose and by loading with drug.
对于药物与珠状纤维素及其衍生物的离子结合情况，没有明显的显著阻滞现象。由于存在这种不足，作为模型药物的苯佐卡因通过与酶固定化方法类似的甲亚胺键共价结合到二醛珠状纤维素上。与相同条件下纯苯佐卡因的溶解速率相比，在磷酸盐缓冲液中的释放速率较低且不完全。通过将甲亚胺还原为胺键，释放速率进一步降低。严格来说，并未实现药物释放的阻滞。释放药物的主要部分在最初20分钟内释放，但6小时后释放速率仍低于可用药物的50%。珠状颗粒的物理性质，如球形形状和孔隙率，不受纤维素氧化和药物负载的显著影响。
