Europium-doped NaGd(WO4)2 nanophosphors: synthesis, luminescence and their coating with fluorescein for pH sensing. Issue 35 (7th August 2017)

• Record Type: Journal Article
• Authors: Laguna, Mariano; Escudero, Alberto; Núñez, Nuria O.; Becerro, Ana I.; Ocaña, Manuel
• Is Part Of: Dalton transactions. Volume 46:Issue 35(2017)
• Page Start: 11575
• Page End: 11583
• Publication Date: 2017-08-07
• Subjects: Chemistry, Inorganic -- Periodicals; Chemistry, Physical and theoretical -- Periodicals; Chemistry, Inorganic -- Periodicals; 546.05
• DOI: 10.1039/c7dt01986f
• Languages: English
• ISSNs: 1477-9226

Abstract

Abstract : Uniform nanospheres of Eu : NaGd(WO4 )2 have been synthesized and further coated with fluorescein to develop a ratiometric pH sensor for biotechnological applications. Abstract : Uniform Eu-doped NaGd(WO4 )2 nanophosphors with a spherical shape have been synthesized for the first time by using a wet chemistry method based on a homogeneous precipitation process at low temperature (120 °C) in ethylene glycol/water mixtures. The obtained nanoparticles crystallized into the tetragonal structure and presented polycrystalline character. The europium content in such phosphors has been optimized through the analysis of the luminescence dynamics (lifetime measurements). By coating the Eu 3+ -doped wolframate based nanoparticles with fluorescein through a layer-by-layer (LbL) approach, a wide range (4–10) ratiometric pH-sensitive sensor has been developed, which uses the pH insensitive emission of Eu 3+ as a reference.