resumo
The application of nanoparticles in the biological context generally requires their dispersion in aqueous media. In this sense, luminescent nanoparticles are an excellent choice for minimally invasive imaging and local temperature sensing (nanothermometry). For these applications, nanoparticles must operate in the physiological temperature range (25-50 degrees C) but also in the near-infrared spectral range (750-1800 nm), which comprises the three biological windows of maximal tissue transparency to photons. In this range, water displays several absorption bands that can strongly affect the optical properties of the nanoparticles. Therefore, a full understanding of the temperature dependence of water absorption in biological windows is of paramount importance for applications based on these optical properties. Herein, the absorption spectrum of water in the biological windows over the 25-65 degrees C temperature range is systematically analyzed, and its temperature dependence considering the coexistence of two states of water is interpreted. Additionally, to illustrate the importance of state-of-the-art applications, the effects of the absorption of water on the emission spectrum of Ag2S nanoparticles, the most sensitive luminescent nanothermometers for in vivo applications to date, are presented. The spectral shape of the nanoparticles' emission is drastically affected by the water absorption, impacting their thermometric performance.
palavras-chave
SPECTRUM
categoria
Chemistry; Science & Technology - Other Topics; Materials Science
autores
Munoz-Ortiz, T; Abiven, L; Marin, R; Hu, J; Ortgies, DH; Benayas, A; Gazeau, F; Castaing, V; Viana, B; Chaneac, C; Jaque, D; Maturi, FE; Carlos, LD; Rodriguez, EM; Sole, JG
nossos autores
Fernando Eduardo Maturi
Bolseiro de investigação
Luís Carlos
Professor Catedráticoagradecimentos
This work was financed by the Spanish Ministerio de Ciencia e Innovacion under project PID2019-106211RB-I00, by the Instituto de Salud Carlos III (PI19/00565), by the Comunidad Autonoma de Madrid (S2017/BMD3867 RENIM-CM) and co-financed by the European structural and investment fund. Additional funding was provided by the European Union Horizon 2020 FETOpen project NanoTBTech (801305), the Fundacion para la Investigacion Biomedica del Hospital Universitario Ramon y Cajal project IMP21_A4 (2021/0427), and by COST action CA17140. A.B. acknowledges funding support through the TALENTO 2019T1/IND14014 contract (Comunidad Autonoma de Madrid). F.E.M. and L.D.C. acknowledge the financial support received from the project Shape of Water (PTDC/NAN-PRO/3881/2020) through Portuguese funds.