具有靶向抗癌作用的Ag2S＠碳量子点复合物的合成与性能研究

Cancers with their various kinds, in recent years, bypassing cerebrovascular disease, have become the number one killer of human health. However, the drugs used in chemotherapy have exhibited great limit. Using a combination of the physical and chemical methods, the present project choses the green and environment friendly carbon sources such as potato and beet to synthesize the specific element doped carbon nanodots with small and evenly distributed particle size, which also possess high fluorescence quantum yield and high stability. Induced by an ultra violet light source, the present project will synthesize nanocomposites of carbon nanodots, Ag2S, as well as the natural product such as flavonoids through a facial ligand exchange, modification, or grafts. The nanocomposite products in the present project are expected to have anticancer effect themselves and meanwhile, be able to perform targeted drug delivery. Because of their photoluminescence, those nanocomposites can be monitored as they transport in and interact with various parts of the cell. Thus, the mechanism of the cancer cell growth, drug delivery, as well as the interaction between anticancer drug and cell can be potentially revealed. The results of the present project will provide theoretical guidance to the development of anticancer medicines and build a strong foundation for the similar research.

近年来，癌症已超过心脑血管疾病成为人类健康的头号杀手，针对目前治疗癌症所用化疗药物普遍存在的局限性，本项目拟选择绿色环保、简单易得、西部地区资源丰富的生物质（如马铃薯、甜菜根）为碳源，以物理和化学手段相结合的方法合成具有高荧光产率，高稳定性，粒径小且分布均匀的碳量子点；采用紫外光照射表面配体交换技术、表面修饰和表面接枝等方法将碳量子点与Ag2S量子点以及具有抗癌作用的天然有机物（如黄酮类）复合，形成同时具有靶向药物传递和抗癌作用的纳米粒子复合物。然后作用于癌细胞，通过动物体内荧光特性进行跟踪观察药物释放过程以及与癌细胞相互作用的过程，研究作用机理，从而为癌症的治疗和药物研发提供理论指导和实验依据。

细菌对传统抗生素产生耐药性，而且在全球迅速扩散，给人类生命健康带来巨大威胁，对新的可替代抗菌剂的需求愈发迫切。纳米科学的快速发展为抗菌治疗提供了潜在的替代方法。与传统的抗生素相比，由于纳米材料具有较强的膜渗透性，以及多种抗菌作用的潜力，因此不易引起细菌耐药性。但是单一纳米材料的抗菌性能并不理想，如基于金属的纳米材料具有良好的抗菌性能，却由于细胞毒性限制了其使用；碳基纳米材料具有良好的生物相容性，但抗菌性能却并不理想。将不同的纳米材料进行复合，制备具有优良的抗菌性能，低细胞毒性的纳米复合材料是解决这一问题的关键。. 本项目以生物质材料为碳源，硫脲为氮源和硫源，采用水热法合成氮硫共掺杂碳量子点（NS-CQDs）。并基于碳量子点（CQDs）和硫化银(Ag2S)，制备了CQDs/Ag2S/CS复合抗菌材料、CS/Ag2S/CQDs抗菌水凝胶和g-C3N4/CQDs/Ag2S光催化抗菌材料，优化了复合物的制备且进行了活性检测。测试复合药物在生物医学方面的性质时，主要进行了体外抗氧化，抗炎症等测试和比较研究。同时进行反馈调节，优化反应过程和各成分的摩尔比，结合各种表征手段和生物医学性质检测手段，考察其热稳定性和化学稳定性，最终得到性能优异的杂化复合物。采用MTT法检测CS/Ag2S/CQDs水凝胶对HePG2的细胞毒性。并进一步对大肠杆菌，金黄色葡萄球菌和耐甲氧西林金黄色葡萄球菌三类菌株做了抗菌性能测试，最后进行了抗肿瘤性能的测试。顺利完成了计划，取得了部分成果，为后续的研究奠定了技术基础。