title: Development of fluorescent thermoresponsive nanoparticles for temperature monitoring on membrane surfaces.
abstract: In this work, tris(phenantroline)ruthenium(II) chloride (Ru(phen)3) was immobilized in silica nanoparticles prepared according to the Stöber method. Efforts were devoted on the optimization of the nano-thermometer in terms of size, polydispersity, intensity of the emission and temperature sensitivity. In particular, the immobilization of the luminophore in an external thin shell made of silica grown in a second step on bare silica nanoparticles allowed producing fluorescent monodisperse silica nanoparticles (420±20nm). A systematic study was addressed to maximize the intensity of the emission of the fluorescent nanoparticles by adjusting the concentration of Ru(phen)32+in the shell from 0.2 to 24wt.%, whereas the thickness of the shell is affected by the amount of silica precursor employed. The luminescent activity of the doped nanoparticles was found to be sensitive to the temperature. In fact, the intensity of the emission linearly decreased by increasing the temperature from 20°C to 65°C. The thermoresponsive nanoparticles were functionalized with long aliphatic chains in order to obtain hydrophobic nanoparticles. The developed nanoparticles were immobilized via dip-coating procedure on the surface of hydrophobic porous membranes, such as Polyvinylidene fluoride (PVDF) prepared via Non-Solvent Induced Phase Separation (NIPS), providing local information about the membrane surface temperature.
authors.affiliation: Institute of Nanoscience of Aragon (INA) and Department of Chemical, Engineering and Environmental Technology, University of Zaragoza, C/ Mariano Esquillor, s/n, I+D+i Building, 50018 Zaragoza, Spain; LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
authors.forename: S
authors.initials: S
authors.lastname: Santoro
authors.affiliation: Institute of Nanoscience of Aragon (INA) and Department of Chemical, Engineering and Environmental Technology, University of Zaragoza, C/ Mariano Esquillor, s/n, I+D+i Building, 50018 Zaragoza, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Centro de Investigación Biomédica en Red. C/ Monforte de Lemos 3-5, Pabellón 11, 28029 Madrid, Spain.
authors.forename: V
authors.initials: V
authors.lastname: Sebastian
authors.affiliation: LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
authors.forename: A J
authors.initials: AJ
authors.lastname: Moro
authors.affiliation: LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
authors.forename: C A M
authors.initials: CAM
authors.lastname: Portugal
authors.affiliation: LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
authors.forename: J C
authors.initials: JC
authors.lastname: Lima
authors.affiliation: LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
authors.forename: I M
authors.initials: IM
authors.lastname: Coelhoso
authors.affiliation: LAQV, REQUIMTE, Departamento de Química, Faculdade de Ciências e Tecnologia, Universidade Nova de Lisboa, 2829-516 Caparica, Portugal.
authors.forename: J G
authors.initials: JG
authors.lastname: Crespo
authors.affiliation: Institute of Nanoscience of Aragon (INA) and Department of Chemical, Engineering and Environmental Technology, University of Zaragoza, C/ Mariano Esquillor, s/n, I+D+i Building, 50018 Zaragoza, Spain; CIBER de Bioingeniería, Biomateriales y Nanomedicina (CIBER-BBN), Centro de Investigación Biomédica en Red. C/ Monforte de Lemos 3-5, Pabellón 11, 28029 Madrid, Spain. Electronic address: rmallada@unizar.es.
authors.forename: R
authors.initials: R
authors.lastname: Mallada
keywords: Core-shell silica; Fluorescent nanoparticles; Nanothermometer