摘要
利用改进的Hummers法氧化鳞片石墨,获得富含羟基和羧基的氧化石墨烯量子点(GOQDs).通过透射电子显微镜、X射线衍射、红外光谱及拉曼光谱测试表征其理化性质.此外,利用鸡卵清蛋白(OVA)作为模式抗原,构筑GOQDs/OVA纳米疫苗并评估其载量、安全性、免疫效力等.结果显示,GOQDs/OVA纳米疫苗直径在5 nm左右,具有高度的水分散性和稳定性.其对OVA的最大负载量约为500mg·g-1,在pH=5.5和7.4环境下24 h的释放率分别为74.65％和56.93％,表现出pH刺激响应释放性能.当GOQDs浓度在500 μg·mL-1以下时,不会引起溶血、细胞损伤、重要组织发生病变等现象.免疫后,与OVA单独免疫对照组相比,GOQDs/OVA纳米疫苗可以诱导产生高水平的免疫球蛋白G(IgG)、免疫球蛋白 G1(IgG1)及免疫球蛋白G2a(IgG2a)抗体,提高白细胞介素(IL)-1β、IL-2、IL-4和IL-6、肿瘤坏死因子-α(TNF-α)和γ干扰素(IFN-γ)的分泌,同时促进脾中辅助性(CD4+)和细胞毒性(CD8+)T淋巴细胞百分比的增加.
Abstract
The improved Hummers method was used to obtain GOQDs from flake graphite,which contained rich hydroxyl and carboxyl groups.With the as-fabricated GOQDs in hand,we constructed a GOQDs/OVA nano-vaccine using chicken ovalbumin(OVA)as a model antigen to evaluate the immune efficacy and safety.Results showed that GOQDs/OVA nano-vaccine had high water dispersibility and stability with a diameter of around 5 nm for 30 d.The maximum loading capacity of GOQDs for OVA was about 500 mg·g-1,and release rates of OVA were 74.65％and 56.93％in pH 5.5 and 7.4 after 24 h,respectively,displaying pH stimulus responsive release merits.With the con-centration of GOQDs below 500 μg·mL-1,the biosecurity of GOQDs indicated that they were not causing hemolysis,cell damage,and pathological changes in important tissues.After immunization,GOQDs/OVA nano-vaccines could excite the high levels of immunoglobulin G(IgG),immunoglobulin G1(IgG 1),and immunoglobulin G2a(IgG2a)anti-bodies and improve secretions of interleukin-1 β(IL-1β),interleukin-4(IL-2),interleukin-4(IL-4),interleukin-6(IL-6),tumor necrosis factor-α(TNF-α),and interferon-γ(IFN-γ),compared with the group of OVA alone.Mean-while,GOQDs promoted an increase in the percentage of CD4+and CD8+T lymphocytes in the spleen.
基金项目
江苏省重点研发计划(BE2020336)
江苏省农业科技自主创新资金项目(CX222018)
维普
万方数据