title: Fabricating a reversible and regenerable Raman-active substrate with a biomolecule-controlled DNA nanomachine.
abstract: A DNA configuration switch is designed to fabricate a reversible and regenerable Raman-active substrate. The substrate is composed of a Au film and a hairpin-shaped DNA strand (hot-spot-generation probes, HSGPs) labeled with dye-functionalized silver nanoparticles (AgNPs). Another ssDNA that recognizes a specific trigger is used as an antenna. The HSGPs are immobilized on the Au film to draw the dye-functionalized AgNPs close to the Au surface and create an intense electromagnetic field. Hybridization of HSGP with the two arm segments of the antenna forms a triplex-stem structure to separate the dye-functionalized AgNPs from the Au surface, quenching the Raman signal. Interaction with its trigger releases the antenna from the triplex-stem structure, and the hairpin structure of the HSGP is restored, creating an effective "off-on" Raman signal switch. Nucleic acid sequences associated with the HIV-1 U5 long terminal repeat sequences and ATP are used as the triggers. The substrate shows excellent reversibility, reproducibility, and controllability of surface-enhanced Raman scattering (SERS) effects, which are significant requirements for practical SERS sensor applications.
authors.affiliation: Molecular Science and Biomedicine Laboratory, College of Chemistry and Chemical Engineering, College of Biology, Hunan University, Changsha, 410082, China.
authors.forename: Jing
authors.initials: J
authors.lastname: Zheng
authors.forename: Anli
authors.initials: A
authors.lastname: Jiao
authors.forename: Ronghua
authors.initials: R
authors.lastname: Yang
authors.forename: Huimin
authors.initials: H
authors.lastname: Li
authors.forename: Jishan
authors.initials: J
authors.lastname: Li
authors.forename: Muling
authors.initials: M
authors.lastname: Shi
authors.forename: Cheng
authors.initials: C
authors.lastname: Ma
authors.forename: Ying
authors.initials: Y
authors.lastname: Jiang
authors.forename: Li
authors.initials: L
authors.lastname: Deng
authors.forename: Weihong
authors.initials: W
authors.lastname: Tan
mesh_terms: D004247:DNA / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D036103:Nanotechnology; D012834:Silver / Q000737:chemistry*; D013059:Spectrum Analysis, Raman; D013499:Surface Properties
chemical_list: D012834:Silver; D006046:Gold; D004247:DNA