title: Simple, sensitive and selective detection of dopamine using dithiobis(succinimidylpropionate)-modified gold nanoparticles as colorimetric probes.
abstract: In this paper, we report a simple, sensitive and selective colorimetric visualization of dopamine (DA) using dithiobis(succinimidylpropionate) (DSP)-modified gold nanoparticles (AuNPs) as probes and ferric ions as cross-linkers. Via the standard amine coupling reaction between the amino groups of DA and activated carboxyl groups of DSP, DA molecules can be assembled onto the surface of DSP-AuNPs. Accordingly, Fe(3+) ions induce a change of DSP-AuNPs in color and UV-vis absorbance by coordinating to the catechol groups of the anchored DA. The pH dependence and mechanism of this method are discussed. A detection limit of 2 nM was obtained, which is lower than those achievable with currently used chromatographic and electrochemical techniques. The feasibility for the detection of DA in artificial cerebrospinal fluid has been demonstrated.
authors: College of Chemistry and Chemical Engineering, Anyang Normal University, Anyang, Henan 455000, People's Republic of China. liulin82414@yahoo.com.cn
authors: Lin
authors: L
authors: Liu
authors: Sujuan
authors: S
authors: Li
authors: Leilei
authors: L
authors: Liu
authors: Dehua
authors: D
authors: Deng
authors: Ning
authors: N
authors: Xia
mesh_terms: D003124:Colorimetry / Q000379:methods*; D004298:Dopamine / Q000032:analysis* / Q000737:chemistry; D006046:Gold / Q000737:chemistry*; D006863:Hydrogen-Ion Concentration; D053768:Metal Nanoparticles / Q000737:chemistry*; D013388:Succinimides / Q000737:chemistry*
chemical_list: D013388:Succinimides; D006046:Gold; C011240:dithiobis(succinimidylpropionate); D004298:Dopamine