Division of Pharmaceutics, Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032, India.
Division of Pharmaceutics, Department of Pharmaceutical Technology, Jadavpur University, Kolkata 700032, India.
Carbohydr Polym. 2014 Jun 15;106:414-21. doi: 10.1016/j.carbpol.2014.01.033. Epub 2014 Jan 21.
Partially carboxymethylated guar gum (PCMGG) was crosslinked in situ by Ca(2+) ions during wet massing step of tablet preparation. The resulting tablets were evaluated for the effect of the extent of crosslinking on drug release and matrix swelling. Increase in the concentration of Ca(2+) ions increased the viscosity of gel layer and reduced the water penetration velocity into the matrix with subsequent decrease in swelling of the tablets and drug release. Beyond a certain concentration of Ca(2+) ions, the viscosity of the gel layer decreased and the drug release rate increased primarily due to erosion of the matrix. The mechanism of drug release appeared to be non-Fickian or anomalous transport. The release data also best fitted in zero order equation. The model drug, metronidazole, was compatible with the matrix materials as evident from instrumental analyses. Such formulation may provide flexibility in achieving the desired drug release rate from crosslinked matrix tablets.
部分羧甲基化瓜尔胶（PCMGG）在片剂制备的湿混步骤中通过 Ca（2+）离子原位交联。研究了交联程度对药物释放和基质溶胀的影响。随着 Ca（2+）离子浓度的增加，凝胶层的粘度增加，水进入基质的渗透速度降低，随后片剂的溶胀和药物释放减少。超过一定浓度的 Ca（2+）离子后，凝胶层的粘度降低，药物释放速率增加，主要是由于基质的侵蚀。药物释放的机制似乎是非菲克扩散或异常扩散。释放数据也最符合零级方程。仪器分析表明，模型药物甲硝唑与基质材料相容。这种制剂可以灵活地控制交联基质片剂的药物释放速率。
