Dr. SSB University Institutes of Chemical Engineering and Technology, Panjab University, Chandigarh 160014, India.
Energy Research Centre, Panjab University, Chandigarh 160014, India.
Int J Biol Macromol. 2022 Dec 1;222(Pt A):844-855. doi: 10.1016/j.ijbiomac.2022.09.212. Epub 2022 Sep 26.
Cellulose fibres derived from hemp stalks, a prevalent biowaste in Northern India, were effectively converted into carboxymethyl cellulose (HS-CMC). Novel environmentally benign hydrogels were synthesized from HS-CMC and polyvinyl alcohol (PVA) using citric acid, a green crosslinker employing freeze-drying method. The HS-CMC/PVA hydrogels were successfully used for sustained release of fluoroquinolone antibiotic, norfloxacin. The hydrogels were characterized using FTIR, XRD, FE-SEM, EDS and thermal stability and evaluated for their carbonyl content, swelling ratio, in-vitro drug release behaviour and bactericidal properties. Successful isolation of cellulose from hemp stalks and its conversion into hydrogel with the presence of ester and carbonyl linkages was confirmed by FTIR. Thermal stability was impaired when cellulose fibres were converted into HS-CMC via carboxymethylation, as the crystalline structure was utterly disrupted. For the hydrogel, the equilibrium swelling ratios at pH -1.2 and 7.4 were assessed as 378.4 % and 538.7 %, respectively, higher than reported CMC hydrogels. The norfloxacin (NFX) encapsulated hydrogels exhibited good bactericidal properties with zone of inhibition of 19.2 ± 0.3 mm against E. coli and 16.4 ± 0.4 mm against S. aureus. The in-vitro release of NFX at pH 1.2 was 91 %, higher than pH 7.4 at 82 % with strong adherence to Higuchi kinetics model signifying that the release of NFX is via dissolution and diffusion. The release kinetics at different pH revealed Fickian behaviour establishing the potential of HS-CMC hydrogel for sustained release of norfloxacin.
从印度北部普遍存在的生物废料麻秆中提取的纤维素纤维被有效地转化为羧甲基纤维素（HS-CMC）。使用柠檬酸，一种绿色交联剂，通过冷冻干燥法，从 HS-CMC 和聚乙烯醇（PVA）合成了新型环保水凝胶。HS-CMC/PVA 水凝胶成功地用于氟喹诺酮类抗生素诺氟沙星的缓释。通过傅里叶变换红外光谱（FTIR）、X 射线衍射（XRD）、FE-SEM、EDS 和热稳定性对 HS-CMC/PVA 水凝胶进行了表征，并评估了其羰基含量、溶胀比、体外药物释放行为和杀菌性能。通过 FTIR 证实了从麻秆中成功分离出纤维素，并将其转化为具有酯键和羰基键的水凝胶。当纤维素纤维通过羧甲基化转化为 HS-CMC 时，热稳定性受到损害，因为结晶结构完全被破坏。对于水凝胶，在 pH-1.2 和 7.4 下的平衡溶胀比分别为 378.4%和 538.7%，高于报道的 CMC 水凝胶。包封诺氟沙星（NFX）的水凝胶表现出良好的杀菌性能，对大肠杆菌的抑菌圈为 19.2±0.3mm，对金黄色葡萄球菌的抑菌圈为 16.4±0.4mm。在 pH 1.2 下，NFX 的体外释放率为 91%，高于 pH 7.4 下的 82%，与 Higuchi 动力学模型强烈吻合，表明 NFX 的释放是通过溶解和扩散进行的。不同 pH 值下的释放动力学显示出菲克扩散行为，这表明 HS-CMC 水凝胶具有缓释诺氟沙星的潜力。
