title: Iron(III)-quantity-dependent aggregation-dispersion conversion of functionalized gold nanoparticles.
abstract: Developing gold nanoparticles (AuNPs) with well-designed functionality is highly desirable for boosting the performance and versatility of inorganic-organic hybrid materials. In an attempt to achieve ion recognition with specific signal expressions, we present here 4-piperazinyl-1,8-naphthalimide-functionalized AuNPs for the realization of quantitative recognition of Fe(III) ions with dual (colorimetric and fluorescent) output. The research takes advantage of 1) quantity-controlled chelation-mode transformation of the piperazinyl moiety on the AuNPs towards Fe(III), thereby resulting in an aggregation-dispersion conversion of the AuNPs in solution, and 2) photoinduced electron transfer of a naphthaimide fluorophore on the AuNPs, thus leading to reversible absorption and emission changes. The functional AuNPs are also responsive to pH variations. This strategy for realizing the aggregation-dispersion conversion of AuNPs with returnable signal output might exhibit application potential for advanced nanoscale chemosensors.
authors.affiliation: Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, 21 Nanyang Link, Singapore 637371 (Singapore).
authors.forename: Linyi
authors.initials: L
authors.lastname: Bai
authors.forename: Liangliang
authors.initials: L
authors.lastname: Zhu
authors.forename: Chung Yen
authors.initials: CY
authors.lastname: Ang
authors.forename: Xin
authors.initials: X
authors.lastname: Li
authors.forename: Shaojue
authors.initials: S
authors.lastname: Wu
authors.forename: Yongfei
authors.initials: Y
authors.lastname: Zeng
authors.forename: Hans
authors.initials: H
authors.lastname: Ågren
authors.forename: Yanli
authors.initials: Y
authors.lastname: Zhao
mesh_terms: D006046:Gold / Q000737:chemistry*; D007501:Iron / Q000737:chemistry*; D053768:Metal Nanoparticles / Q000737:chemistry*; D020349:Surface Plasmon Resonance
chemical_list: D006046:Gold; D007501:Iron
keywords: gold; iron; nanoparticles; sensors; surface plasmon resonance