Evaluation of the Drug Release Mechanism of pH-Sensitive Calcium Alginate Hydrogels in Simulated Physiological Fluids

酸鹼敏感型海藻酸鈉在模擬腸胃液之藥物控制釋放行為探討

饒文娟(Win-Chun Jao) ； 胡志明(Liao-Chia Ho) ； 陳震暐(Zhen-Wei Chen)

《中華科技大學學報》 42期 (2010/01) Pp. 37-61

https://doi.org/10.7095/JCUST.201001.0037

摘要

本論文以海藻酸鈉(Alg)為主要材料，氯化鈣為交聯劑製備水膠薄膜，並探討其在模擬腸胃液之藥物控制釋放行為。海藻酸鈉水膠薄膜其特性可用傅利葉轉換紅外光光譜儀檢測。Ca(上标2+)交聯劑的影響可利用有效交聯密度及高分子－溶劑之交互作用參數(χ)由Flory theory 來計算。海藻酸鈉水膠薄膜作為安比西林的控制釋放載體，並比較不同混摻比水膠在模擬腸胃液中控制釋放特性上的差異。此海藻酸鈉水膠薄膜對安比西林的載藥量符合Langmuir 吸附等溫線，其安比西林藥物在模擬胃液(pH1.2)及模擬腸液(pH7.5)的釋放動力學遵循Fickian diffusion機制。海藻酸鈉水膠薄膜釋放安比西林速率及裂解與其Ca(上标 2+)交聯度、海藻酸鈉含量及生理的pH值有相關性。穿透式電子顯微鏡顯示在模擬腸胃液被侵蝕的表面。實驗結果證明海藻酸鈉水膠可適用於腸道的藥物區域傳遞系統。

關鍵字

水膠 ； 安比西林 ； 藥物控制釋放 ； 模擬胃液 ； 模擬腸液 ； 裂解

並列摘要

Calcium alginate hydrogels were prepared and loaded with ampicillin to evaluate their release mechanism in simulated physiological fluids. The calcium alginate hydrogels were characterized using FTIR spectroscopy and the Flory-Rehner equation of equilibrium swelling to calculate the molecular weight between crosslinks and crosslinking density. The loading capacity of ampicillin was followed the Langmuir isotherm model. The drug release and degradation of crosslinked alginate hydrogels were performed in simulated gastric fluid (pH 1.2) and simulated intestinal fluid (pH 7.5). The alginate with higher calcium content exhibited lower drug release rate and degradation rate. The release rate of ampicillin in SIF was higher than that in SGF and followed a Fickian diffusion mechanism. The results were shown that the release kinetics and degradation were significantly dependent on the crosslinking degree of the alignate hydrogels and the physiological pH. SEM micrographs were shown an eroded surface after in the simulated intestinal fluid. The results were indicated that calcium alginate hydrogels might be useful for the localized delivery of drug in the intestinal environment.

並列關鍵字

hydrogel ； ampicillin ； drug release ； simulated gastric fluid ； simulated intestinal fluid ； degradation