新型铜系等离子量子点的生物医学应用及其毒性研究

Plasmonic quantum dots (PQDs) are a novel class of nanomaterial that can be applied in a variety of fields because they exhibit both plasmonic and semiconductor features that enable tuning by synthetic chemistry. This grant proposal aims to fully explore the potential of PQDs for nanomedicine applications, as well as to examine their toxicity. Firstly, the synthesis of Cu2-xE(E = S, Se and Te), will be optimized by changing the ratio of stabilizing agents in the oleic acid and oleylamine system so that PQDs with different physical properties can be obtained. PQDs appear to be superior to the conventional QDs due to three distinct features that originate from their size and the collective oscillations of the free hole carriers i.e. small diameter, and photothermal and photoacoustic effects. PQDs are only 3 – 16 nm in diameter which is excellent for in vivo applications due to a capability of being cleared from the body. The photothermal effect of PQDs can convert the near infrared radiation into heat. In addition, PQDs can be used in photoacoustic imaging as they can convert the near infrared radiation into acoustic waves. The detection mechanism for the PA signal is similar to that used in a clinical ultrasonic transceiver..In order to fully explore the potential of PQDs for nanomedicine applications, the as-synthesized PQDs will be surface modified and functionalized to make them dispersible in water and to serve as drug carriers. The photothermal effect of PQDs can then utilized as a controlled release mechanism that triggers the release of a drug through a near infrared light source. The feasibility of integrating the PA and the ultrasonic system will also be addressed in this proposal, providing useful information as a foundation for utilizing PQDs in a clinical setting..

等离子量子点(Plasmonic quantum dots， PQDs)是一种全新纳米材料， 其独特性质可被广泛应用。 本项目将开发这新材料在生医上的应用， 探讨其潜在毒性。 首先会采用oleic acid 和 oleylamine 系统合成， 通过适当改变实验条件，获得具有不同物理特性的PQD。 PQD同时拥有三个的特质: 粒径小， 光热效应和光声交应。 PQD的粒径只有3 - 16nm， 有利於活体排出， 代谢； 光热效应可把近红外光源转化成热能； 其光声效应的产生则跟临床使用的超声波成像机理相近。 .本项目将PQD注入小老鼠体内， 观察其体内分布和侦测潜在毒性， 建立量子点毒性研究平台。 加入功能基团， 使PQD可携带药物， 构成纳米运药载体， 再以红外光源作控制释放。 结合光声成像与超声波成像系统， 探讨PQD用於临床仪器的可行性， 为开发PQD的临床应用潜能提供基础研究。

等离子量子点(Plasmonic quantum dots， PQDs)是一种全新纳米材料， 其独特性质可被广泛应用。 本项目将开发这新材料在生医上的应用， 探讨其潜在毒性。 .　　我们利用3D打印技术制造模板，通过倒模，采用聚甲基丙烯酸甲酯材料搭建微流体平台。这个平台可以简单地通过改变前驱体的流速以及比例，控制Cu2-xS半导体纳米颗粒的合成过程，获得不同大小和形状的颗粒。纳米晶体的局域表面等离子体共振（LSPR）峰值可以在1115-1644nm之间调整。还利用Cu2-xS纳米晶体的光热效应，在近红外激光照射下湮灭RAW264.7细胞。.　　此外，我们采用复合合成法，制备了近红外发射纳米晶体。这种纳米晶体，不仅在近红外发光上有很高的量子效率（~14%），同时也能够实现核磁共振成像。通过表面修饰RGD短肽链，这种纳米探针已经被用在细胞标记，肿瘤靶向以及淋巴结显像。另外，给小鼠静脉注射25mg / kg QDs。 3周后，收集主要器官组织进行病理学评估。与仅接受缓冲溶液的对照动物相比时，在接受QD的动物组中没有观察到毒性的迹象，表明QD在该剂量下在体内是无毒的。