Pongjanyakul T, Rojtanatanya S
Department of Pharmaceutical Technology, Faculty of Pharmaceutical Sciences, Khon Kaen University, Khon Kaen-40002, Thailand.
Indian J Pharm Sci. 2012 Jul;74(4):292-301. doi: 10.4103/0250-474X.107048.
The objective of the present study was to investigate the use of propranolol-magnesium aluminium silicate intercalated complexes as drug reservoirs in hydroxypropylmethylcellulose tablets. The matrix tablets containing the complexes were prepared and characterised with respect to propranolol release and were subsequently compared with those loading propranolol or a propranolol-magnesium aluminium silicate physical mixture. Additionally, the effects of varying viscosity grades of hydroxypropyl methylcellulose, compression pressures and calcium acetate incorporation on the drug release characteristics of the complex-loaded tablets were also examined. The results showed that the complex-loaded tablets have higher tablet hardness than those containing propranolol or a physical mixture. The drug release from the complex-loaded tablets followed a zero-order release kinetic, whereas an anomalous transport was found in the propranolol or physical mixture tablets. The drug release rate of the complex tablet significantly decreased with increasing hydroxypropylmethylcellulose viscosity grade. Increase in the compression pressure caused a decrease in the drug release rate of the tablets. Furthermore, the incorporation of calcium ions could accelerate propranolol release, particularly in acidic medium, because calcium ions could be exchanged with propranolol molecules intercalated in the silicate layers of magnesium aluminium silicate. These findings suggest that propranolol-magnesium aluminium silicate intercalated complexes show strong potential for use as drug reservoirs in matrix tablets intended for modifying drug release.
本研究的目的是考察普萘洛尔 - 硅酸镁铝插层复合物作为羟丙基甲基纤维素片剂中药物储库的应用。制备了含有该复合物的基质片剂，并对其普萘洛尔释放情况进行了表征，随后与装载普萘洛尔或普萘洛尔 - 硅酸镁铝物理混合物的片剂进行了比较。此外，还研究了不同粘度等级的羟丙基甲基纤维素、压片压力以及醋酸钙的加入对载有复合物片剂药物释放特性的影响。结果表明，载有复合物的片剂比含有普萘洛尔或物理混合物的片剂具有更高的片剂硬度。载有复合物片剂的药物释放遵循零级释放动力学，而在普萘洛尔或物理混合物片剂中发现了非正规转运。随着羟丙基甲基纤维素粘度等级的增加，复合物片剂的药物释放速率显著降低。压片压力的增加导致片剂的药物释放速率降低。此外，钙离子的加入可以加速普萘洛尔的释放，特别是在酸性介质中，因为钙离子可以与插层在硅酸镁铝硅酸盐层中的普萘洛尔分子进行交换。这些发现表明，普萘洛尔 - 硅酸镁铝插层复合物在用作旨在调节药物释放的基质片剂中的药物储库方面具有很大的潜力。
