title: Multifunctional quantum-dot-based siRNA delivery for HPV18 E6 gene silence and intracellular imaging.
abstract: The functional quantum dots (QDs) were specifically designed to overcome barriers in siRNA delivery such as siRNA protection, cellular penetration, endosomal release, carrier unpacking, intracellular transport and gene silencing. In this paper, two l-arginine-functional-modiﬁed CdSe/ZnSe QDs were synthesized as siRNA carriers to silence HPV18 E6 gene in HeLa cells. Using such constructs, these QDs showed significantly low cellular cytotoxicity and good siRNA protection. Flow cytometric and confocal microscopic analyses confirmed that the QDs delivered siRNA into HeLa cells efficiently. Importantly, superior gene silencing efficiency was achieved as evaluated by Reverse Transcription-PCR (RT-PCR) and Western blotting and HeLa cells growth was inhibited in xCELLigence installation analysis and MTT assay when treated with QD-siRNA complexes. Interestingly, the QDs coated with β-CD-l-Arg showed optimized property compared with those coated with l-Arg. Furthermore, these QDs complexes could also be used as nanocrystal probing agents, allowing real-time tracking and localization of QDs during delivery and transfection. The properties and capabilities of these QDs showed that amino acid-modiﬁed QDs could be used as useful siRNA carriers to effectively silence a target gene as well as fluorescence probes to analyze intracellular imaging in vivo.
authors.affiliation: MOE Key Laboratory of Bioinorganic and Synthetic Chemistry, School of Chemistry and Chemical Engineering, Sun Yat-sen University, Guangzhou 510275, China.
authors.forename: Jin-Ming
authors.initials: JM
authors.lastname: Li
authors.forename: Mei-Xia
authors.initials: MX
authors.lastname: Zhao
authors.forename: Hua
authors.initials: H
authors.lastname: Su
authors.forename: Yuan-Yuan
authors.initials: YY
authors.lastname: Wang
authors.forename: Cai-Ping
authors.initials: CP
authors.lastname: Tan
authors.forename: Liang-Nian
authors.initials: LN
authors.lastname: Ji
authors.forename: Zong-Wan
authors.initials: ZW
authors.lastname: Mao
mesh_terms: D000327:Adsorption; D015153:Blotting, Western; D016923:Cell Death; D002470:Cell Survival; D004268:DNA-Binding Proteins; D005434:Flow Cytometry; D005453:Fluorescence; D020868:Gene Silencing; D018014:Gene Transfer Techniques; D006367:HeLa Cells; D006801:Humans; D021621:Imaging, Three-Dimensional / Q000379:methods*; D042541:Intracellular Space / Q000378:metabolism*; D018613:Microscopy, Confocal; D046529:Microscopy, Electron, Transmission; D009856:Oncogene Proteins, Viral / Q000235:genetics*; D045663:Quantum Dots; D034741:RNA, Small Interfering / Q000378:metabolism*; D020133:Reverse Transcriptase Polymerase Chain Reaction; D013997:Time Factors; D014162:Transfection
chemical_list: D004268:DNA-Binding Proteins; C052603:E6 protein, Human papillomavirus type 18; D009856:Oncogene Proteins, Viral; D034741:RNA, Small Interfering