氧化还原/pH双响应性蔗渣纤维素基水凝胶的制备及药物缓释性能

Preparation and Drug Release of Redox/pH Dual-Responsive Bagasse Cellulose-Based Hydrogels

为制备具有氧化还原和pH双响应性水凝胶,以甘蔗渣纤维素为原料,溶解在N,N-二甲基乙酰胺/氯化锂(DMAc/LiCl)溶剂体系中,然后在催化剂条件下,与乙酰乙酸叔丁酯(t-BAA)进行酯交换反应获得乙酰乙酸蔗渣纤维素(BCAA),然后与胱胺二盐酸盐(CYS)反应制得水凝胶。根据红外光谱和扫描电镜分析结果,表明已成功制备出具有烯胺键和二硫键的水凝胶。稳定性和保水性测试表明,水凝胶在生理条件下具有一定的稳定性和保水性。以盐酸四环素作为药物模型,研究了在不同的氧化还原和pH条件下水凝胶的药物释放性能,证明了氧化还原条件和pH会影响水凝胶的药物释放。抗菌实验结果表明,该载药水凝胶对大肠杆菌和金黄色葡萄球菌具有良好的抗菌效果。该氧化还原/pH双响应水凝胶在药物缓释方面具有潜在的应用前景。

In order to prepare redox/pH responsive hydrogels,sugarcane bagasse cellulose was used as raw material and dissolved in N,N-dimethylacetamide/lithium chloride(DMAc/LiCl)solvent system.The as-prepared cellulose was then coupled with tert-butyl acetoacetate(t-BAA)via catalytic transesterification to obtain bagasse cellulose acetoacetate(BCAA),followed by reacting with cystamine dihydrochloride(CYS)to generate dual-responsive hydrogels.The results of FT-IR and SEM demonstrate the successful incorporation of enamine and disulfide bonds in the hydrogels and porous structure.The stability and water retention tests show that the hydrogels are stable and have a definite water retention under physiological conditions.Moreover,the drug release behaviors of hydrogels were studied under conditions of different redox and pH using tetracycline hydrochloride(TH)as model drug.The results indicate that both redox and pH conditions could control the drug release of hydrogels.Meanwhile,the drug-loaded hydrogel exhibits a excellent antibacterial activity against a broad spectrum of bacteria,i.e,both S.aureus and E.coli.Therefore,the redox/pH dual-responsive hydrogels developed in this work have great potential in the applications associated with drug release.