title: Regioselective plasmonic nano-assemblies for bimodal sub-femtomolar dopamine detection.
abstract: Reliable and ultrasensitive quantification of dopamine (DA) is essential in the precise diagnotherapy of neurological diseases. In this study, dual mode counterpropagating-responsive gold@silver nanoparticle-gold nanorod (Au@AgNP-AuNR) nano-assemblies were fabricated for the precise quantification of DA. The plasmonic Au@AgNP-AuNR assemblies possessed high surface-enhanced Raman scattering (SERS) activity and strong fluorescence quenching, due to the prominent electromagnetic enhancement between the hotspots of the assemblies. In the presence of a DA target, the Au@AgNP-AuNR assemblies dissociated, leading to an increase in fluorescence intensity and a decrease in SERS intensity. The limit of detection (LOD) of DA was 0.04 fM and 0.02 fM by the fluorescence method and SERS method, respectively. The linear range was 0.1-10 fM. These findings demonstrated that the simultaneous positive fluorescence response and negative SERS response ensured the accurate detection of DA, which opens up a new avenue for the early diagnotherapy of neurological diseases.
authors.affiliation: State Key Laboratory of Food Science and Technology, Jiangnan University, Wuxi, Jiangsu 214122, People's Republic of China. wuxiaoling@jiangnan.edu.cn kuangh@jiangnan.edu.cn.
authors.forename: Fengli
authors.initials: F
authors.lastname: Gao
authors.forename: Liqiang
authors.initials: L
authors.lastname: Liu
authors.forename: Gang
authors.initials: G
authors.lastname: Cui
authors.forename: Liguang
authors.initials: L
authors.lastname: Xu
authors.forename: Xiaoling
authors.initials: X
authors.lastname: Wu
authors.forename: Hua
authors.initials: H
authors.lastname: Kuang
authors.forename: Chuanlai
authors.initials: C
authors.lastname: Xu
mesh_terms: D004298:Dopamine / Q000032:analysis* / Q000097:blood; D005453:Fluorescence; D006046:Gold; D006801:Humans; D053768:Metal Nanoparticles; D012834:Silver; D013059:Spectrum Analysis, Raman
chemical_list: D012834:Silver; D006046:Gold; D004298:Dopamine