Abstract：
A sodium alginate (Alg) based REDOX (reduction and oxidation)-responsive and fluorescent active microgel was prepared via water in oil (w/o) mini-emulsion polymerization technique. Here, we initially synthesized sodium alginate-based disulfide cross linked microgels and after that those microgels were tagged with rhodamine amine derivative (RhB-NH2) by ionic interaction to get the pH-responsive fluorescent property. Functionalized microgels were characterized using 1H NMR, FTIR, DLS, HRTEM, FESEM, UV-vis, and fluorescence spectroscopy analyses. Presence of the REDOX-responsive disulfide-containing crosslinkers in the microgels enhances the release of doxorubicin (DOX), an anti-cancer drug in the reducing environment of the cancer-cells (simulated). Existence of the rhodamine-amine derivative in the microgels triggers the pH-dependent fluorescence property by showing fluorescence emission at 560-580 nm at pH 5.5 (cancer cell pH). The cytotoxicity of the biopolymer based microgel was assessed over both cancerous HeLa (IC50 100 µg/mL) and non-cancerous MDCK (IC50 200 µg/mL) cells by MTT assay which showed the synthesized microgel is non-toxic whereas DOX-loaded microgels showed significant toxicity. FACS and cell uptake (in vitro) analyses were conducted to understand the cell apoptosis cycle and behavior of the cancer cells in presence of the DOX-loaded microgels. This pH-responsive fluorescent active alginate-based biomaterial could be a promising material for the anti-cancer drug delivery and other medical fields.
摘要：
通过油包水（w/o）微乳液聚合技术制备了基于海藻酸钠（Alg）的REDOX（还原和氧化）响应性和荧光活性微凝胶。这里,我们最初合成了基于海藻酸钠的二硫化物交联微凝胶，然后通过离子相互作用用罗丹明胺衍生物（RhB-NH2）标记这些微凝胶，以获得pH响应性荧光特性。使用1HNMR表征功能化的微凝胶，FTIR,DLS,HRTEM,FESEM，UV-vis,和荧光光谱分析。微凝胶中REDOX响应的含二硫化物交联剂的存在增强了阿霉素（DOX）的释放，一种在癌细胞还原环境中的抗癌药物（模拟）。微凝胶中罗丹明-胺衍生物的存在通过在pH5.5(癌细胞pH)下在560-580nm处显示荧光发射而触发pH依赖性荧光性质。通过MTT测定,在癌性HeLa(IC50100μg/mL)和非癌性MDCK(IC50200μg/mL)细胞上评估基于生物聚合物的微凝胶的细胞毒性,其显示合成的微凝胶是无毒的,而装载DOX的微凝胶显示出显著的毒性。进行FACS和细胞摄取(体外)分析以了解细胞凋亡周期和在负载DOX的微凝胶存在下癌细胞的行为。这种pH响应性荧光活性基于藻酸盐的生物材料可能是用于抗癌药物递送和其他医学领域的有前途的材料。
