title: Plasmon Coupling Enhanced Raman Scattering Nanobeacon for Single-Step, Ultrasensitive Detection of Cholera Toxin.
abstract: We report the development of a novel plasmon coupling enhanced Raman scattering (PCERS) method, PCERS nanobeacon, for ultrasensitive, single-step, homogeneous detection of cholera toxin (CT). This method relies on our design of the plasmonic nanoparticles, which have a bilayer phospholipid coating with embedded Raman indicators and CT-binding ligands of monosialoganglioside (GM1). This design allows a facile synthesis of the plasmonic nanoparticle via two-step self-assembly without any specific modification or chemical immobilization. The realization of tethering GM1 on the surface imparts the plasmonic nanoparticles with high affinity, excellent specificity, and multivalence for interaction with CT. The unique lipid-based bilayer coated structure also affords excellent biocompatibility and stability for the plasmonic nanoparticles. The plasmonic nanoparticles are able to show substantial enhancement of the surface-enhanced Raman scattering (SERS) signals in a single-step interaction with CT, because of their assembly into aggregates in response to the CT-sandwiched interactions. The results reveal that the developed nanobeacon provides a simple but ultrasensitive sensor for rapid detection of CT with a large signal-to-background ratio and excellent reproducibility in a wide dynamic range, implying its potential for point-of-care applications in preventive and diagnostic monitoring of cholera.
authors.affiliation: State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Chong-Hua
authors.initials: CH
authors.lastname: Zhang
authors.affiliation: State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Ling-Wei
authors.initials: LW
authors.lastname: Liu
authors.affiliation: State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Ping
authors.initials: P
authors.lastname: Liang
authors.affiliation: State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Li-Juan
authors.initials: LJ
authors.lastname: Tang
authors.affiliation: State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Ru-Qin
authors.initials: RQ
authors.lastname: Yu
authors.affiliation: State Key Laboratory of Chemo/Bio-Sensing and Chemometrics, College of Chemistry and Chemical Engineering, Hunan University , Changsha, Hunan 410082, P. R. China.
authors.forename: Jian-Hui
authors.initials: JH
authors.lastname: Jiang
mesh_terms: D015060:1,2-Dipalmitoylphosphatidylcholine / Q000737:chemistry; D015374:Biosensing Techniques / Q000379:methods*; D002772:Cholera Toxin / Q000032:analysis* / Q000737:chemistry; D005677:G(M1) Ganglioside / Q000737:chemistry; D006046:Gold / Q000737:chemistry; D008051:Lipid Bilayers / Q000737:chemistry; D053768:Metal Nanoparticles / Q000737:chemistry*; D013059:Spectrum Analysis, Raman / Q000379:methods*; D020349:Surface Plasmon Resonance; D014280:Triglycerides / Q000737:chemistry
chemical_list: C520656:1,2-dipalmitoyl-sn-glycero-3-phosphothioethanol; D008051:Lipid Bilayers; D014280:Triglycerides; D015060:1,2-Dipalmitoylphosphatidylcholine; D005677:G(M1) Ganglioside; D006046:Gold; D002772:Cholera Toxin