title: Plasmonic polymers with strong chiroptical response for sensing molecular chirality.
abstract: We report on the chiroptical transfer and amplification effect observed in plasmonic polymers consisting of achiral gold nanorod monomers linked by cysteine chiral molecules in an end-to-end fashion. A new strategy for controlling the hot spots based circular dichroism (CD)-active sites in plasmonic polymers was developed to realize tailored and reproducible chiroptical activity in a controlled way. We showed that by regulating the bond angles between adjacent nanorods and the degree of polymerization in the linear plasmonic polymer, weak molecular chirality in the ultraviolet spectral region can be amplified by more than two orders of magnitude via the induced CD response in the visible/near infrared region. We demonstrate that this plasmonic polymer can be used to provide not only the Raman "fingerprint" information for identifying the molecular identity but also the CD signatures for (i) resolving the enantiomeric pairs of cysteine molecules at a small quantity level, and (ii) quantifying the enantiomeric purity of the chiral analytes. Chiral analyses by chiroptically responsive plasmonic polymers may find important applications in bioscience and biomedicine.
authors.affiliation: Key Laboratory of Cluster Science of Ministry of Education, School of Physics, Beijing Institute of Technology, Beijing, 100081, P R China. wangry@bit.edu.cn.
authors.forename: Dawei
authors.initials: D
authors.lastname: Zhai
authors.forename: Peng
authors.initials: P
authors.lastname: Wang
authors.forename: Rong-Yao
authors.initials: RY
authors.lastname: Wang
authors.forename: Xiaorui
authors.initials: X
authors.lastname: Tian
authors.forename: Yinglu
authors.initials: Y
authors.lastname: Ji
authors.forename: Wenjing
authors.initials: W
authors.lastname: Zhao
authors.forename: Luming
authors.initials: L
authors.lastname: Wang
authors.forename: Hong
authors.initials: H
authors.lastname: Wei
authors.forename: Xiaochun
authors.initials: X
authors.lastname: Wu
authors.forename: Xiangdong
authors.initials: X
authors.lastname: Zhang
mesh_terms: D003461:Crystallography / Q000379:methods; D006046:Gold / Q000737:chemistry* / Q000528:radiation effects; D008027:Light; D053768:Metal Nanoparticles / Q000737:chemistry* / Q000528:radiation effects; D008968:Molecular Conformation; D015336:Molecular Probe Techniques; D015335:Molecular Probes / Q000737:chemistry; D043942:Nanotubes / Q000737:chemistry* / Q000528:radiation effects; D011108:Polymers / Q000737:chemistry* / Q000528:radiation effects; D013237:Stereoisomerism; D020349:Surface Plasmon Resonance / Q000379:methods*
chemical_list: D015335:Molecular Probes; D011108:Polymers; D006046:Gold