abstract
Selecting a suitable host matrix to perform temperature sensing in biomedical applications requires low cytotoxicity, facile synthesis, and an ability to be doped with light-emitting ions. With this perspective, indium-based halide double perovskites, specifically Cs2AgIn0.9Bi0.1Cl6, Cs2Ag0.6Na0.4InCl6, and Cs2Ag0.6Na0.4In0.9Bi0.1Cl6, were chosen as host materials to develop lanthanide-based primary thermometers due to their low phonon energy and ease of synthesis. The incorporation of Na+ and Bi3+ into the perovskite cubic crystal lattice was confirmed by X-ray diffraction and Raman spectroscopy while the optical properties of both the undoped and Yb3+/Er3+ co-doped perovskites were assessed by diffuse reflectance and photoluminescence spectroscopies. The obtained perovskite samples demonstrated excellent thermal stability, with the ability to withstand temperatures as high as 500 degrees C. A temperature-dependent green emission of Er3+ was observed in the co-doped samples upon 980 nm irradiation, yielding a relative thermal sensitivity and uncertainty in temperature values of 1.3% K-1 and 0.3 K, respectively. Incorporating the obtained perovskites (0.05 to 0.20 mg mL(-1)) into L2929 cells as an in vitro model resulted in high cell viability, underscoring the benefits of selecting such a low-cytotoxicity material for applications in biological media.
keywords
NEAR-INFRARED EMISSION; UP-CONVERSION; BAND; NANOPARTICLES; THERMOMETERS; LANTHANIDE; NANOPROBES; ENERGY
subject category
Materials Science; Physics
authors
Passini, LN; Maturi, FE; Pugina, RS; Hilário, EG; Fontes, M; Barud, HS; Carlos, LD; Caiut, JMA; Manzani, D
our authors
acknowledgements
The authors acknowledge the financial support provided by the Brazilian research grants from Sao Paulo Research Foundation - FAPESP (2018/16126-7, 2021/08111-2, and 2019/18828-1), CAPES, and CNPq-Universal (424917/2018-1 and 405048/2021-1). F. E. M. acknowledges the funding received from the European Union's Horizon 2020 research and innovation programme under the Marie Sklodowska-Curie grant agreement no. 823941 (FUNGLASS) and the financial support from the Foundation for Science and Technology (FCT) through the Portuguese research grant UI/BD/151445/2021.