title: Boosting the sensitivity of Nd(3+)-based luminescent nanothermometers.
abstract: Luminescence thermal sensing and deep-tissue imaging using nanomaterials operating within the first biological window (ca. 700-980 nm) are of great interest, prompted by the ever-growing demands in the fields of nanotechnology and nanomedicine. Here, we show that (Gd1-xNdx)2O3 (x = 0.009, 0.024 and 0.049) nanorods exhibit one of the highest thermal sensitivity and temperature uncertainty reported so far (1.75 ± 0.04% K(-1) and 0.14 ± 0.05 K, respectively) for a nanothermometer operating in the first transparent near infrared window at temperatures in the physiological range. This sensitivity value is achieved using a common R928 photomultiplier tube that allows defining the thermometric parameter as the integrated intensity ratio between the (4)F5/2 → (4)I9/2 and (4)F3/2 → (4)I9/2 transitions (with an energy difference between the barycentres of the two transitions >1000 cm(-1)). Moreover, the measured sensitivity is one order of magnitude higher than the values reported so far for Nd(3+)-based nanothermometers enlarging, therefore, the potential of using Nd(3+) ions in luminescence thermal sensing and deep-tissue imaging.
authors.affiliation: Department of Physics and CICECO Aveiro Institute of Materials, University of Aveiro, 3810-193 Aveiro, Portugal. lcarlos@ua.pt.
authors.forename: Sangeetha
authors.initials: S
authors.lastname: Balabhadra
authors.forename: Mengistie L
authors.initials: ML
authors.lastname: Debasu
authors.forename: Carlos D S
authors.initials: CD
authors.lastname: Brites
authors.forename: Luís A O
authors.initials: LA
authors.lastname: Nunes
authors.forename: Oscar L
authors.initials: OL
authors.lastname: Malta
authors.forename: João
authors.initials: J
authors.lastname: Rocha
authors.forename: Marco
authors.initials: M
authors.lastname: Bettinelli
authors.forename: Luís D
authors.initials: LD
authors.lastname: Carlos
mesh_terms: D008163:Luminescent Measurements / Q000379:methods*; D053758:Nanoparticles / Q000737:chemistry*; D009354:Neodymium / Q000737:chemistry*; D012680:Sensitivity and Specificity; D013821:Thermometers
chemical_list: D009354:Neodymium