title: Nanoscopic assemblies between supramolecular redox active metallodendrons and gold nanoparticles: synthesis, characterization, and selective recognition of H2PO4-, HSO4-, and adenosine-5'-triphosphate (ATP2-) anions.
abstract: Tri- and nonaferrocenyl thiol dendrons have been synthesized and used to assemble dendronized gold nanoparticles either by the ligand-substitution method from dodecanethiolate-gold nanoparticles (AB(3) units) or Brust-type direct synthesis from a 1:1 mixture of dodecanethiol and dendronized thiol (AB(9) units). The dendronized colloids are a new type of dendrimers with a gold colloidal core. Two colloids containing a nonasilylferrocenyl dendron have been made; they bear respectively 180 and 360 ferrocenyl units at the periphery. These colloids selectively recognize the anions H(2)PO(4)(-) and adenosine-5'-triphosphate (ATP(2)(-)) with a positive dendritic effect and can be used to titrate these anions because of the shift of the CV wave even in the presence of other anions such as Cl(-) and HSO(4)(-). Recognition is monitored by the appearance of a new wave at a less positive potential in cyclic voltammetry (CV). The anion HSO(4)(-) is also recognized and titrated by the dendronized colloid containing the tris-amidoferrocenyl units, because of the progressive shift of the CV wave until the equivalence point. These dendronized colloids can form robust modified electrodes by dipping the naked Pt electrode into a CH(2)Cl(2) solution containing the colloids. The robustness is all the better as the dendron is larger. These modified electrodes can recognize H(2)PO(4)(-), ATP(2)(-) and HSO(4)(-), be washed with minimal loss of adsorbed colloid, and be reused.
authors.affiliation: Groupe Nanoscience et Catalyse, LCOO, UMR CNRS Nomicron. 5802, Université Bordeaux I, 33405 Talence Cedex, France.
authors.forename: Marie-Christine
authors.initials: MC
authors.lastname: Daniel
authors.forename: Jaime
authors.initials: J
authors.lastname: Ruiz
authors.forename: Sylvain
authors.initials: S
authors.lastname: Nlate
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Blais
authors.forename: Didier
authors.initials: D
authors.lastname: Astruc
mesh_terms: D000255:Adenosine Triphosphate / Q000032:analysis / Q000737:chemistry*; D000473:Alkanes / Q000138:chemical synthesis / Q000737:chemistry*; D000838:Anions; D003102:Colloids / Q000138:chemical synthesis / Q000737:chemistry; D004563:Electrochemistry; D004566:Electrodes; D005296:Ferrous Compounds / Q000737:chemistry*; D006046:Gold / Q000737:chemistry*; D000075163:Metallocenes; D036103:Nanotechnology / Q000379:methods; D010084:Oxidation-Reduction; D010710:Phosphates / Q000032:analysis / Q000737:chemistry*; D013431:Sulfates / Q000032:analysis / Q000737:chemistry*; D013438:Sulfhydryl Compounds / Q000138:chemical synthesis / Q000737:chemistry*; D017186:Titrimetry
chemical_list: D000473:Alkanes; D000838:Anions; D003102:Colloids; D005296:Ferrous Compounds; D000075163:Metallocenes; D010710:Phosphates; D013431:Sulfates; D013438:Sulfhydryl Compounds; C007548:n-dodecane; D006046:Gold; D000255:Adenosine Triphosphate; C004998:ferrocene