title: Joining time-resolved thermometry and magnetic-induced heating in a single nanoparticle unveils intriguing thermal properties.
abstract: Whereas efficient and sensitive nanoheaters and nanothermometers are demanding tools in modern bio- and nanomedicine, joining both features in a single nanoparticle still remains a real challenge, despite the recent progress achieved, most of it within the last year. Here we demonstrate a successful realization of this challenge. The heating is magnetically induced, the temperature readout is optical, and the ratiometric thermometric probes are dual-emissive Eu(3+)/Tb(3+) lanthanide complexes. The low thermometer heat capacitance (0.021·K(-1)) and heater/thermometer resistance (1 K·W(-1)), the high temperature sensitivity (5.8%·K(-1) at 296 K) and uncertainty (0.5 K), the physiological working temperature range (295-315 K), the readout reproducibility (>99.5%), and the fast time response (0.250 s) make the heater/thermometer nanoplatform proposed here unique. Cells were incubated with the nanoparticles, and fluorescence microscopy permits the mapping of the intracellular local temperature using the pixel-by-pixel ratio of the Eu(3+)/Tb(3+) intensities. Time-resolved thermometry under an ac magnetic field evidences the failure of using macroscopic thermal parameters to describe heat diffusion at the nanoscale.
authors.affiliation: †Departamento de Fisica de la Materia Condensada, Facultad de Ciencias and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Piñol
authors.affiliation: ‡Departamento de Física and CICECO Aveiro Institute of Materials, Universidade de Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Carlos D S
authors.initials: CD
authors.lastname: Brites
authors.affiliation: †Departamento de Fisica de la Materia Condensada, Facultad de Ciencias and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
authors.forename: Rodney
authors.initials: R
authors.lastname: Bustamante
authors.affiliation: §Departamento de Electrónica de Potencia. I3A, Universidad de Zaragoza, 50018 Zaragoza, Spain.
authors.forename: Abelardo
authors.initials: A
authors.lastname: Martínez
authors.affiliation: ‡Departamento de Física and CICECO Aveiro Institute of Materials, Universidade de Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Nuno J O
authors.initials: NJ
authors.lastname: Silva
authors.affiliation: †Departamento de Fisica de la Materia Condensada, Facultad de Ciencias and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
authors.forename: José L
authors.initials: JL
authors.lastname: Murillo
authors.affiliation: †Departamento de Fisica de la Materia Condensada, Facultad de Ciencias and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
authors.forename: Rafael
authors.initials: R
authors.lastname: Cases
authors.affiliation: ∥Laboratoire de Physique et Chimie des Nano-Objets (LPCNO)Université de Toulouse, INSA, UPS, CNRS (UMR 5215), F-31077, Toulouse, France.
authors.forename: Julian
authors.initials: J
authors.lastname: Carrey
authors.affiliation: †Departamento de Fisica de la Materia Condensada, Facultad de Ciencias and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
authors.forename: Carlos
authors.initials: C
authors.lastname: Estepa
authors.affiliation: ⊥Departamento de Toxicología, Facultad de Veterinaria, Universidad de Zaragoza, 50013 Zaragoza, Spain.
authors.forename: Cecilia
authors.initials: C
authors.lastname: Sosa
authors.affiliation: †Departamento de Fisica de la Materia Condensada, Facultad de Ciencias and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
authors.forename: Fernando
authors.initials: F
authors.lastname: Palacio
authors.affiliation: ‡Departamento de Física and CICECO Aveiro Institute of Materials, Universidade de Aveiro, 3810-193 Aveiro, Portugal.
authors.forename: Luís D
authors.initials: LD
authors.lastname: Carlos
authors.affiliation: †Departamento de Fisica de la Materia Condensada, Facultad de Ciencias and Instituto de Ciencia de Materiales de Aragón, CSIC-Universidad de Zaragoza, 50009 Zaragoza, Spain.
authors.forename: Angel
authors.initials: A
authors.lastname: Millán
mesh_terms: D000818:Animals; D002460:Cell Line; D005063:Europium / Q000737:chemistry; D006358:Hot Temperature; D042541:Intracellular Space; D060526:Magnetic Fields; D053758:Nanoparticles; D036103:Nanotechnology / Q000379:methods*; D013725:Terbium / Q000737:chemistry; D013821:Thermometers; D013997:Time Factors
chemical_list: D013725:Terbium; D005063:Europium
keywords: heat diffusion; intracellular temperature; magnetic hyperthermia; nanoheaters; nanothermometers