SEMINAR
The State Key Lab of
High Performance Ceramics and Superfine Microstructure
Shanghai Institute of Ceramics, Chinese Academy of Sciences
中 国 科 学 院 上 海 硅 酸 盐 研 究 所 高 性 能 陶 瓷 和 超 微 结 构 国 家 重 点 实 验 室

　　基于多功能磁性纳米颗粒的肿瘤靶向诊断与治疗

　　Speaker

　　侯仰龙 教授

　　北京大学

　　时间：2015年08月27日（星期四）下午 15: 00

　　地点： 2号楼607会议室 （国家重点实验室）

　　欢迎广大科研人员和研究生参与讨论！

　　报告人简介：

　　侯仰龙：教育部长江学者特聘教授，北京大学教授、博士生导师。主要从事多功能磁性材料、新能源材料的控制合成及其在纳米生物医学与能源领域的应用探索研究。发展了单分散磁性纳米材料的通用制备方法，提出了自下而上的纳米耦合磁体化学制备新策略、探索了磁性纳米颗粒在肿瘤等重大疾病的诊断与治疗的应用。迄今发表学术论文100余篇，在国际和各类双边会议上作大会或分会邀请报告30余次。荣获北京市科技新星（2008）、教育部新世纪优秀人才（2009）、北京市优秀人才（2009）、霍英东优秀青年教师奖（2009）、青年科学之星新人奖（2010）、国家杰出青年基金获得者（2011）、北京茅以升青年科技奖（2011）、绿叶生物医药杰出青年学者奖（2012）、中国化学会-英国皇家化学会青年化学奖（2013）、教育部长江学者特聘教授（2014）和科技部中青年科技创新领军人才（2014）。正主持或参加国家杰出青年基金、国家重大基础研究计划（973）等课题。现任Scientific Reports(NPG)、Advanced Science (Wiley)、Science China Materials、Rare Metals等期刊编委，中国材料研究会理事、中国化学会理事、中国生物材料学会理事、中国化学会青年化学工作者委员会副主任委员等。

　　报告摘要：

　　Magnetic nanoparticles (NPs), which possess controlled size, shape and magnetic moments, have been applied as multifunctional probes in biomedical field, including MRI, drug delivery and magnetic hyperthermia, by enhancement of contrast in magnetic resonance imaging (MRI) and emote manipulation.^[1] In this talk, we will first present general protol of monodisperse magnetic NPs, and then give an example of hollow manganese phosphate (HMP) NPs with particle size of 18 nm and a 10 nm hollow structure, for pH-modulated cancer cell targeted MRI and drug delivery. ^[2] Folic acid (FA) was selected as a target molecular for specific binding with cancer cells, and doxorubicin was loaded into the hollow structure for cancer therapy. This multifucntional probe can speci?cally target cancer cells overexpressing FA receptors, and be engulfed by lysosomes. The HMP NPs were dissolved at low pH environment in lysosomes, which can release Mn2+ for sensitive MRI, and DOX loaded for effective killing of cancer cells. ^[3]

　　We then talk about Hagg iron carbide (Fe₅C₂) magnetic NPs for bimodal tumor imaging and therapy (Scheme). ^[4-6] Interestingly, due to the presence of carbon layers of NPs, with high absorption in near-infrared (NIR) optical region, Fe5C2 NPs can be used for photoacoustic tomography (PAT) and photothermal therapy (PTT). The probe exhibits high saturation magnetization, r2 relaxivity and temperature increasing after exposure to NIR. The conjugation of Herceptin enabled the targeting to Her2-overexpressed cells (SK-OV-3 cells). After incubation with NPs in vitro, SK-OV-3 cells showed much lower MRI T₂ signal, and no noticeable in vitro toxicity has been observed. Determined by using a fluorescent viability stain, cells incubated with NPs and exposed to NIR light were found to have undergone photothermally induced morbidity. The in vivo experiments were carried out on nude mice with ovarian cancer modal. After injection of NPs through the tail vein, it showed long-lasting negative-contrast enhancement MRI as well as high PAT signal at the tumor site. High tumore ablation was achieved after NIR irritation. From the loss of body weight, morphological and pathological examinations, almost no systematic toxicity has been observed. Our results highlight the great potential of Fe₅C₂ NPs as a multifunctional probe for cancer theranostic applications.

　　References:

1. Hao R, Xing R & Hou Y*, et al., Adv. Mater., 2010, 22, 2729-2742.
2. Hao R, Yu J & Hou Y*, et al., Chem. Commun., 2011, 47, 9095-9097.
3. Yu J, Hao R & Hou Y*, et al., Nano Res., 2012, 5, 679-694.
4. Yang C, Zhao & Hou Y*, et al., J. Am. Chem. Soc., 2012, 134, 15814-15821.
5. Tang W, Zhen Z & Hou Y*, et al., Small 2014, 7, 1245–1249.
6. Yu J, Yang C & Hou Y*, et al, Adv. Mater., 2014, 26, 4114-4120.