title: An engineered coiled-coil polypeptide assembled onto quantum dots for targeted cell imaging.
abstract: Quantum dot (QD)-polypeptide probes have been developed through the specific metal-affinity interaction between polypeptides appended with N-terminal polyhistidine sequences and CdSe/ZnS core-shell QDs. The size and charge of a QD-polypeptide can be tuned by using different coiled-coil polypeptides. Compared to glutathione-capped QDs (QD-GSH), QD-polypeptide probes showed an approximately two- to three-fold luminescence increase, and the luminescence increase was not obviously related to the charge of the polypeptide. QD-polypeptide probes with different charge have a great effect on nonspecific cellular uptake. QD-polypeptide probes with negative charge exhibited lower nonspecific cellular uptake in comparison to the QD-GSH, while positively charged QD-polypeptide probes presented higher cellular uptake than the QD-GSH. A targeted QD-ARGD probe can obviously increase targeted cellular uptake in α v β 3 overexpressing HeLa cells compared to QD-A. In addition, QD-polypeptide probes showed lower in vitro cytotoxicity compared to the original QDs. These results demonstrate that these QD-polypeptide probes with high specific cellular uptake, high fluorescence intensity and low background noise are expected to have great potential applications in targeted cell imaging.
authors.forename: Ming-Hao
authors.initials: MH
authors.lastname: Yao
authors.forename: Jie
authors.initials: J
authors.lastname: Yang
authors.forename: Ji-Tao
authors.initials: JT
authors.lastname: Song
authors.forename: Lin
authors.initials: L
authors.lastname: Zhang
authors.forename: Bi-Yun
authors.initials: BY
authors.lastname: Fang
authors.forename: Dong-Hui
authors.initials: DH
authors.lastname: Zhao
authors.forename: Rui-Xue
authors.initials: RX
authors.lastname: Xia
authors.forename: Rui-Mei
authors.initials: RM
authors.lastname: Jin
authors.forename: Yuan-Di
authors.initials: YD
authors.lastname: Zhao
authors.forename: Bo
authors.initials: B
authors.lastname: Liu
mesh_terms: D003584:Cytological Techniques / Q000379:methods*; D006367:HeLa Cells; D006801:Humans; D061986:MCF-7 Cells; D061848:Optical Imaging / Q000379:methods*; D010455:Peptides / Q000737:chemistry*; D045663:Quantum Dots / Q000737:chemistry*
chemical_list: D010455:Peptides