title: Enhanced cell uptake via non-covalent decollation of a single-walled carbon nanotube-DNA hybrid with polyethylene glycol-grafted poly(l-lysine) labeled with an Alexa-dye and its efficient uptake in a cancer cell.
abstract: The use of single-walled carbon nanotubes (SWNTs) for biomedical applications is a promising approach due to their unique outer optical stimuli response properties, such as a photothermal response triggered by near-IR laser irradiation. The challenging task in order to realize such applications is to render the SWNTs biocompatible. For this purpose, the stable and homogeneous functionalization of the SWNTs with a molecule carrying a biocompatible group is very important. Here, we describe the design and synthesis of a polyanionic SWNT/DNA hybrid combined with a cationic poly(l-lysine) grafted by polyethylene glycol (PLL-g-PEG) to provide a supramolecular SWNT assembly. A titration experiment revealed that the assembly undergoes an approximately 1 : 1 reaction of the SWNT/DNA with PLL-g-PEG. We also found that SWNT/DNA is coated with PLL-g-PEG very homogeneously that avoids the non-specific binding of proteins on the SWNT surface. The experiment using the obtained supramolecular hybrid was carried out in vitro and a dramatic enhancement in the cell uptake efficiency compared to that of the SWNT/DNA hybrid without PLL-g-PEG was found.
authors.affiliation: Department of Applied Chemistry, Graduate School of Engineering, Kyushu University, 744 Motooka, Fukuoka, Japan.
authors.forename: Tsuyohiko
authors.initials: T
authors.lastname: Fujigaya
authors.forename: Yuki
authors.initials: Y
authors.lastname: Yamamoto
authors.forename: Arihiro
authors.initials: A
authors.lastname: Kano
authors.forename: Atsushi
authors.initials: A
authors.lastname: Maruyama
authors.forename: Naotoshi
authors.initials: N
authors.lastname: Nakashima
mesh_terms: D045744:Cell Line, Tumor; D004247:DNA / Q000737:chemistry*; D005456:Fluorescent Dyes / Q000737:chemistry*; D006801:Humans; D018625:Microscopy, Atomic Force; D037742:Nanotubes, Carbon / Q000737:chemistry*; D009369:Neoplasms / Q000378:metabolism / Q000473:pathology; D011092:Polyethylene Glycols / Q000737:chemistry*; D011107:Polylysine / Q000031:analogs & derivatives* / Q000737:chemistry; D013059:Spectrum Analysis, Raman
chemical_list: D005456:Fluorescent Dyes; D037742:Nanotubes, Carbon; C443714:polylysine-graft-(poly(ethylene glycol)); D011107:Polylysine; D011092:Polyethylene Glycols; D004247:DNA