Unexpected Chirality of Nanoparticle Dimers and Ultrasensitive Chiroplasmonic Bioanalysis.
Chiral assemblies of nanoparticles (NPs) are typically constructed with helical or tetrahedral geometries. Simple pairs of NPs are not expected to display chirality due to basic symmetry considerations made under the assumption of their spherical geometry. In this study we demonstrate that assemblie...
| Publicado en: | Journal of the American Chemical Society Vol. 135; no. 49; pp. 18629 - 18637 |
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| Autores principales: | , , , , , , , , |
| Formato: | Artículo |
| Publicado: |
American Chemical Society
12/11/2013
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| Materias: | |
| Acceso en línea: | Ver este registro en EBSCOhost |
| fields | @attributes: recordID: 1 pdfLink: plink: https://search.ebscohost.com/login.aspx?direct=true&db=hlh&AN=93379885&site=ehost-live header: @attributes: shortDbName: hlh uiTerm: 93379885 longDbName: Humanities International Complete uiTag: AN controlInfo: bkinfo: jinfo: jid: 00027863 ACS jtl: Journal of the American Chemical Society issn: 00027863 maglogo: N pubinfo: dt: 12/11/2013 vid: 135 iid: 49 pid: 997 pub: American Chemical Society artinfo: ui: 93379885 10.1021/ja4095445 ppf: 18629 ppct: 8 formats: tig: atl: Unexpected Chirality of Nanoparticle Dimers and Ultrasensitive Chiroplasmonic Bioanalysis. aug: au: Xiaoling Wu Liguang Xu Liqiang Liu Wei Ma Honghong Yin Hua Kuang Libing Wang Chuanlai Xu Kotov, Nicholas A. affil: State Key Lab of Food Science and Technology, School of Food Science and Technology, Jiangnan University, Wuxi, JiangSu 214122, P.R. China Departments of Chemical Engineering, Materials Science, and Biomedical Engineering, and Biointerfaces Institute, University of Michigan, Ann Arbor, Michigan 48109, United States su: Chirality Nanoparticles Dimers Antigens Optical polarization Immunoglobulins Biocomplexity sug: subj: Chirality Nanoparticles Dimers Antigens Optical polarization Immunoglobulins Biocomplexity ab: Chiral assemblies of nanoparticles (NPs) are typically constructed with helical or tetrahedral geometries. Simple pairs of NPs are not expected to display chirality due to basic symmetry considerations made under the assumption of their spherical geometry. In this study we demonstrate that assemblies consisting of two metallic NPs do possess chirality and strongly rotate polarization of light. Their chiroplasmonic properties are attributed to the prolate geometry of individual colloidal particles. When bridged by biomolecules, the NP pairs acquire scissor-like geometry, with the long axes of NPs forming an angle of ∼9°. This small dihedral angle results in chirality of the NP pair, while the consistency of its sign due to the specific conformation of the bridging biomacromolecules breaks the enantiomeric equivalence of the NP pairs. Strong polarization rotation in these nanoassemblies makes possible their utilization in biological analysis. Heterodimers of gold and silver NPs were made using antibody-antigen bridges. Taking advantage of their chiroplasmonic properties, we investigated their bioanalitical potential for detection of an environmental toxin, microcystin-LR, and a cancer biomarker, prostate-specific antigen. The order-of-magnitude improvements in limits of detection compared to all other analytical techniques are attributed to plasmonic enhancement of intrinsic chirality of biological compounds, strong optical coupling of photons with NP assemblies with twisted geometries, and signal amplification due to the bisignate nature of circular dichroism bands. pubtype: Academic Journal doctype: Article src: R language: English refInfo: copyright: @attributes: flag: Y dt: @attributes: year: 2013 holdings: @attributes: islocal: N |
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