Thiolated DAB dendrimers and CdSe quantum dots nanocomposites for Cd(II) or Pb(II) sensing

• Published in: Talanta (Oxford) Vol. 88; pp. 403 - 407
• Main Authors: Algarra, M., Campos, B.B., Alonso, B., Miranda, M.S., Martínez, Á.M., Casado, C.M., Esteves da Silva, J.C.G.
• Format: Journal Article
• Language: English
• Published: Amsterdam Elsevier B.V 15.01.2012; Elsevier
• Subjects: Analytical chemistry; Cadmium selenides; Cd(II); CdSe quantum dots; Chemistry; DAB dendrimer; Dendrimers; Exact sciences and technology; Fluorescence; General, instrumentation; Mathematical analysis; Nanocomposite sensor; Nanocomposites; Pb(II); Quantum dots; Quenching; Sensors; Spectrometric and optical methods; Thiolated DAB dendrimer; Pb(II); DAB dendrimer; Nanocomposite sensor; Thiolated DAB dendrimer; Cd(II); CdSe quantum dots; Thiol; CD(II); Fluorescence; Metal ion; Selectivity; PB(II); Concentration; Chemical sensor; Fluorescence spectrometry; Lead II; Cadmium II; Limitation; Detection limit; Nanocomposite
• ISSN: 0039-9140; 1873-3573
• DOI: 10.1016/j.talanta.2011.11.007

► Four different generation of thiol-DAB dendrimers were synthesized. ► Fluorescent nanocomposites of the thiol-DAB dendrimers with CdSe quantum dots were obtained. ► The fluorescent S-DAB-G5-CdSe nanocomposites are sensors for Cd(II) and Pb(II) ions. Four different generation of thiol-DAB dendrimers were synthesized, S-DAB-Gx (x=1, 2, 3 and 5), and coupled with CdSe quantum dots, to obtain fluorescent nanocomposites as metal ions sensing. Cd(II) and Pb(II) showed the higher enhancement and quenching effects respectively towards the fluorescence of S-DAB-G5-CdSe nanocomposite. The fluorescence enhancement provoked by Cd(II) can be linearized using a Henderson–Hasselbalch type equation and the quenching provoked by Pb(II) can be linearized by a Stern–Volmer equation. The sensor responds to Cd(II) ion in the 0.05–0.7μM concentration range and to Pb(II) ion in the 0.01–0.15mM concentration range with a LOD of 0.06mM. The sensor has selectivity limitations but its dendrimer configuration has analytical advantages.