title: Polyamine-capped gold nanorod as a localized surface Plasmon resonance probe for rapid and sensitive copper(II) ion detection.
abstract: Polyamine-capped gold nanorods (AuNRs) were developed as nanoprobes for localized surface Plasmon resonance (LSPR)-based simple, selective, and sensitive detection of Cu(2+) ions. Poly(sodium-4-styrenesulfonate) (PSS) and polyethylenimine (PEI) was successively adsorbed on the positively charged AuNRs via electrostatic adsorption, resulting in polyamine-capped AuNRs (called "PEI-PSS-AuNRs" thereafter), in which PEI offered bifunctions of providing sufficient positive charges and static hindrance to ensure stability of the AuNRs and serving as a Cu(2+) ion recognition molecule via specific chelation. The as-prepared PEI-PSS-AuNRs were characterized by UV-vis spectroscopy, zeta potential analyzer, and transmission electron microscopy (TEM). Experimental results show that the polyelectrolytes PSS and PEI have been successfully adsorbed on AuNRs. The PEI-PSS-AuNRs were then employed as nanoprobes for Cu(2+) ion detection. A linear range from 1μM to 5mM and a detection limit (3σ/k) of 0.24μM were achieved in PBS. The concentration dependent shifts of longitudinal extinction peak of PEI-PSS-AuNRs notably results from the specific PEI-Cu(2+) chelation-induced changes of dielectric property of polyelectrolyte film attached on nanoprobes. The negligible interference from other metal ions demonstrates good selectivity of the PEI-PSS-AuNRs for Cu(2+) sensing. Moreover, the developed probes were successfully used to detect Cu(2+) in river water, demonstrating their feasibility for analysis of surface water sample.
authors.affiliation: Institute for Clean Energy & Advanced Materials, Faculty of Materials & Energy, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center for Rapid Diagnosis of Dread Disease, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies, Southwest University, Chongqing 400715, China. Electronic address: ysliu@swu.edu.cn.
authors.forename: Yingshuai
authors.initials: Y
authors.lastname: Liu
authors.affiliation: Institute for Clean Energy & Advanced Materials, Faculty of Materials & Energy, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center for Rapid Diagnosis of Dread Disease, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies, Southwest University, Chongqing 400715, China.
authors.forename: Yanan
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: Institute for Clean Energy & Advanced Materials, Faculty of Materials & Energy, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center for Rapid Diagnosis of Dread Disease, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies, Southwest University, Chongqing 400715, China.
authors.forename: Yuchen
authors.initials: Y
authors.lastname: Wang
authors.affiliation: Institute for Clean Energy & Advanced Materials, Faculty of Materials & Energy, Southwest University, Chongqing 400715, China; Chongqing Engineering Research Center for Rapid Diagnosis of Dread Disease, Southwest University, Chongqing 400715, China; Chongqing Key Laboratory for Advanced Materials and Technologies of Clean Energies, Southwest University, Chongqing 400715, China.
authors.forename: Chang Ming
authors.initials: CM
authors.lastname: Li
mesh_terms: D002623:Chemistry Techniques, Analytical / Q000295:instrumentation*; D003300:Copper / Q000032:analysis*; D006046:Gold / Q000737:chemistry*; D057230:Limit of Detection; D053768:Metal Nanoparticles / Q000737:chemistry; D043942:Nanotubes / Q000737:chemistry*; D011073:Polyamines / Q000737:chemistry*; D020349:Surface Plasmon Resonance
chemical_list: D011073:Polyamines; D006046:Gold; D003300:Copper
keywords: Cu(2+) detection; Gold nanorods; Localized surface Plasmon resonance; Polyethylenimine