title: Thiolated DAB dendrimer/ZnSe nanoparticles for C-reactive protein recognition in human serum.
abstract: A nanocomposite obtained by a thiol DAB-dendrimer (generation 5), coated with fluorescent ZnSe quantum dots, was successfully synthesized for the selective recognition of C-reactive protein. The procedure presented was carried out by a novel, cheap and non-toxic bottom up synthesis. The nanocomposite showed an excitation at 180 nm, with two emission bands at 411 and 465 nm, with a full-width at half-maximum of 336 nm. The Stokes shift was influenced by the presence of coating molecules and the intensity was dependent on pH due to the presence of a charge transfer process. The transmission electron microscopy images demonstrated that the spherical nanoparticles obtained displayed a regular shape of 30 nm size. The fluorescence intensity was markedly quenched by the presence of C-reactive protein, with a dynamic Stern-Volmer constant of 0.036 M(-1). The quenching profile shows that about 51% of the ZnSe QDs are located in the external layer of the thiol dendrimer accessible to the quencher. The precision of the method obtained as relative standard deviation was 3.76% (4 mg L(-1), n=3). This water soluble fluorescent nanocomposite showed a set of favorable properties to be used as a sensor for the C-reactive protein in serum samples, at concentrations of risk levels.
authors.affiliation: Centro de Geología, Departamento de Geociências, Ambiente e Ordenamento do Território do Porto, Faculdade de Ciências da Universidade do Porto, Porto, Portugal. magonzal@fc.up.pt
authors.forename: M
authors.initials: M
authors.lastname: Algarra
authors.forename: B B
authors.initials: BB
authors.lastname: Campos
authors.forename: D
authors.initials: D
authors.lastname: Gomes
authors.forename: B
authors.initials: B
authors.lastname: Alonso
authors.forename: C M
authors.initials: CM
authors.lastname: Casado
authors.forename: M M
authors.initials: MM
authors.lastname: Arrebola
authors.forename: M J
authors.initials: MJ
authors.lastname: Diez de los Rios
authors.forename: M E
authors.initials: ME
authors.lastname: Herrera-Gutiérrez
authors.forename: G
authors.initials: G
authors.lastname: Seller-Pérez
authors.forename: J C G
authors.initials: JC
authors.lastname: Esteves da Silva
mesh_terms: D001774:Blood Chemical Analysis / Q000379:methods*; D002097:C-Reactive Protein / Q000032:analysis*; D050091:Dendrimers / Q000737:chemistry*; D004983:Ethanolamines / Q000737:chemistry; D006801:Humans; D006863:Hydrogen-Ion Concentration; D053758:Nanoparticles / Q000737:chemistry*; D009994:Osmolar Concentration; D011126:Polypropylenes / Q000737:chemistry*; D018036:Selenium Compounds / Q000737:chemistry*; D013050:Spectrometry, Fluorescence; D013438:Sulfhydryl Compounds / Q000737:chemistry*; D017967:Zinc Compounds / Q000737:chemistry*
chemical_list: D050091:Dendrimers; D004983:Ethanolamines; D011126:Polypropylenes; D018036:Selenium Compounds; D013438:Sulfhydryl Compounds; D017967:Zinc Compounds; C443641:poly(propyleneimine); C005448:phosphorylethanolamine; D002097:C-Reactive Protein; C044696:zinc selenide