title: Luminescent Helical Nanofiber Self-Assembled from a Cholesterol-Based Metalloamphiphile and Its Application in DNA Conformation Recognition.
abstract: Compared to pure organic amphiphiles, metalloamphiphiles display distinctive features, including luminescence, magnetism and catalytic properties. However, the self-organization of metalloamphiphiles is commonly driven by solvophobic effects. Alkyl chains and oligomeric ethylene glycol moieties are thus the most frequently used aggregation units to drive the self-assembly of metalloamphiphiles. We expect novel metallo-supramolecular structures with exciting functions to be created if additional noncovalent interaction modes are incorporated. In this work, a new type of metalloamphiphile, consisting of a Tb(III) complex head and a cholesteryl unit (TbL3+(I)), was designed and synthesized. TbL3+(I) spontaneously self-assembles into helical nanofibers (d = 6 nm) in water. This synthetic multivalent nanoscale binding array displays powerful capability for the recognition of DNA conformations through a turn-on luminescence sensing mechanism. ssDNA-kit1 triggered a 26-fold increase in the luminescence intensity of TbL3+(I). Its corresponding G-quadruplex structure (G-quadruplex-kit1), however, induced a 6.6-fold enhancement under the same conditions. Consequently, TbL3+(I) nanofibers can monitor DNA folding. In contrast, neither ssDNA-kit1 nor G-quadruplex-kit1 markedly promoted the luminescence of molecularly dispersed TbL3+(II), illustrating that the multivalent electrostatic interactions between the phosphate groups on the backbone of DNA and TbL3+(I) self-assembled into nanofibers could greatly improve the efficiency of the energy transfer between the guanine units and the organized TbL3+(I). The TbL3+(I) nanofibers could bind and distinguish not only the kit1-ssDNA/G-quadruplex but also the conformations of other G-rich DNA, such as spb1, htelo, and intermolec-htelo. The self-assembly of luminescent metalloamphiphiles thus provides a general and convenient strategy for the efficient recognition and conversion of molecular information.
authors.affiliation: Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University , Xi'an 710062, People's Republic of China.
authors.forename: Hairui
authors.initials: H
authors.lastname: Lei
authors.affiliation: Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University , Xi'an 710062, People's Republic of China.
authors.forename: Jing
authors.initials: J
authors.lastname: Liu
authors.affiliation: Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University , Xi'an 710062, People's Republic of China.
authors.forename: Junlin
authors.initials: J
authors.lastname: Yan
authors.affiliation: Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University , Xi'an 710062, People's Republic of China.
authors.forename: Jingmiao
authors.initials: J
authors.lastname: Quan
authors.affiliation: Key Laboratory of Applied Surface and Colloid Chemistry, Ministry of Education, School of Chemistry & Chemical Engineering, Shaanxi Normal University , Xi'an 710062, People's Republic of China.
authors.forename: Yu
authors.initials: Y
authors.lastname: Fang
mesh_terms: D002784:Cholesterol / Q000031:analogs & derivatives* / Q000138:chemical synthesis / Q000737:chemistry; D056831:Coordination Complexes / Q000138:chemical synthesis / Q000737:chemistry*; D004277:DNA, Single-Stranded / Q000737:chemistry* / Q000235:genetics; D054856:G-Quadruplexes; D049449:Luminescence; D049408:Luminescent Agents / Q000138:chemical synthesis / Q000737:chemistry*; D057139:Nanofibers / Q000737:chemistry*; D009690:Nucleic Acid Conformation; D013501:Surface-Active Agents / Q000138:chemical synthesis / Q000737:chemistry*; D013725:Terbium / Q000737:chemistry
chemical_list: D056831:Coordination Complexes; D004277:DNA, Single-Stranded; D049408:Luminescent Agents; D013501:Surface-Active Agents; D013725:Terbium; D002784:Cholesterol