Joining Time-Resolved Thermometry and Magnetic-Induced Heating in a Single Nanoparticle Unveils Intriguing Thermal Properties

authors	Pinol, R; Brites, CDS; Bustamante, R; Martinez, A; Silva, NJO; Murillo, JL; Cases, R; Carrey, J; Estepa, C; Sosa, C; Palacio, F; Carlos, LD; Millan, A
nationality	International
journal	ACS NANO
author keywords	nanothermometers; nanoheaters; magnetic hyperthermia; intracellular temperature; heat diffusion
keywords	IRON-OXIDE NANOPARTICLES; MOLECULAR THERMOMETER; LIVING CELLS; TEMPERATURE; HYPERTHERMIA; NANOSCALE; FIELD
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 Eu3+/Tb3+ lanthanide complexes. The low thermometer heat capacitance (0.021 center dot K-1) and heater/thermometer resistance (1 K center dot W-1), the high temperature sensitivity (5.8%center dot 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 Eu3+/Tb3+ intensities. Time-resolved thermometry under an ac magnetic field evidences the failure of using Macroscopic thermal parameters to describe heat diffusion at the nanoscale.
publisher	AMER CHEMICAL SOC
issn	1936-0851
year published	2015
volume	9
issue	3
beginning page	3134
ending page	3142
digital object identifier (doi)	10.1021/acsnano.5b00059
web of science category	Chemistry, Multidisciplinary; Chemistry, Physical; Nanoscience & Nanotechnology; Materials Science, Multidisciplinary
subject category	Chemistry; Science & Technology - Other Topics; Materials Science
unique article identifier	WOS:000351791800086