Yong Ken-Tye, Ding Hong, Roy Indrajit, Law Wing-Cheung, Bergey Earl J, Maitra Anirban, Prasad Paras N
Institute for Lasers, Photonics and Biophotonics, University at Buffalo, The State University of New York, Buffalo, New York 14260-4200, USA.
ACS Nano. 2009 Mar 24;3(3):502-10. doi: 10.1021/nn8008933.
In this paper, we report the successful use of non-cadmium-based quantum dots (QDs) as highly efficient and nontoxic optical probes for imaging live pancreatic cancer cells. Indium phosphide (core)-zinc sulfide (shell), or InP/ZnS, QDs with high quality and bright luminescence were prepared by a hot colloidal synthesis method in nonaqueous media. The surfaces of these QDs were then functionalized with mercaptosuccinic acid to make them highly dispersible in aqueous media. Further bioconjugation with pancreatic cancer specific monoclonal antibodies, such as anticlaudin 4 and antiprostate stem cell antigen (anti-PSCA), to the functionalized InP/ZnS QDs, allowed specific in vitro targeting of pancreatic cancer cell lines (both immortalized and low passage ones). The receptor-mediated delivery of the bioconjugates was further confirmed by the observation of poor in vitro targeting in nonpancreatic cancer based cell lines which are negative for the claudin-4-receptor. These observations suggest the immense potential of InP/ZnS QDs as non-cadmium-based safe and efficient optical imaging nanoprobes in diagnostic imaging, particularly for early detection of cancer.
在本文中，我们报道了成功使用非镉基量子点（QDs）作为高效且无毒的光学探针来对活的胰腺癌细胞进行成像。通过在非水介质中采用热胶体合成法制备了具有高质量和明亮发光特性的磷化铟（核）-硫化锌（壳），即InP/ZnS量子点。然后用巯基琥珀酸对这些量子点的表面进行功能化处理，使其在水介质中具有高度分散性。将胰腺癌特异性单克隆抗体，如抗claudin 4和抗前列腺干细胞抗原（anti-PSCA），进一步与功能化的InP/ZnS量子点进行生物偶联，从而实现对胰腺癌细胞系（包括永生化细胞系和低传代细胞系）的特异性体外靶向。通过观察在对claudin-4受体呈阴性的非胰腺癌基础细胞系中体外靶向性较差，进一步证实了生物偶联物的受体介导递送。这些观察结果表明InP/ZnS量子点作为非镉基安全高效的光学成像纳米探针在诊断成像中，特别是在癌症早期检测方面具有巨大潜力。
