Suchergebnisse

The implementation of in vivo fluorescence imaging as a reliable diagnostic imaging modality at the clinical level is still far from reality. Plenty of work remains ahead to provide medical practitioners with solid proof of the potential advantages of this imaging technique. To do so, one of the key objectives is to better the optical performance of dedicated contrast agents, thus improving the resolution and penetration depth achievable. This direction is followed here and the use of a novel AgInSe2 nanoparticle-based contrast agent (nanocapsule) is reported for fluorescence imaging. The use of an Ag2Se seeds-mediated synthesis method allows stabilizing an uncommon orthorhombic crystal structure, which endows the material with emission in the second biological window (1000–1400 nm), where deeper penetration in tissues is achieved. The nanocapsules, obtained via phospholipid-assisted encapsulation of the AgInSe2 nanoparticles, comply with the mandatory requisites for an imaging contrast agent—colloidal stability and negligible toxicity—and show superior brightness compared with widely used Ag2S nanoparticles. Imaging experiments point to the great potential of the novel AgInSe2-based nanocapsules for high-resolution, whole-body in vivo imaging. Their extended permanence time within blood vessels make them especially suitable for prolonged imaging of the cardiovascular system ; J.Y. acknowledges the support from the China Scholarship Council (CSC File No. 201704910867). R.M. acknowledges the support of the European Commission through the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant Agreement No. 797945 (LANTERNS). P.R. is grateful for a Juan de la Cierva – Incorporación scholarship (IJC2019-041915-I). This work was supported by the Ministerio de Ciencia e Innovación de España under projects MAT2016-75362-C3-1-R, MAT2017-83111R, and MAT2017-85617-R, by the Instituto de Salud Carlos III (PI16/00812), by the Comunidad Autónoma de Madrid (B2017/BMD3867/RENIM-CM, PID2019-106211RB-I00), and cofinanced by the European Structural and investment fund. Additional funding was provided by the European Union Horizon 2020 FETOpen project NanoTBTech (801305), the Fundación para la Investigación Biomédica del Hospital Universitario Ramón y Cajal project IMP18_38 (2018/0265), and also by COST action CA17140. E.X. is grateful for a Juan de la Cierva Formación scholarship (FJC2018-036734-I)

Deliberate and local increase of the temperature within solid tumors represents an effective therapeutic approach. Thermal therapies embrace this concept leveraging the capability of some species to convert the absorbed energy into heat. To that end, magnetic hyperthermia (MHT) uses magnetic nanoparticles (MNPs) that can effectively dissipate the energy absorbed under alternating magnetic fields. However, MNPs fail to provide real-time thermal feedback with the risk of unwanted overheating and impeding on-the-fly adjustment of the therapeutic parameters. Localization of MNPs within a tissue in an accurate, rapid, and cost-effective way represents another challenge for increasing the efficacy of MHT. In this work, MNPs are combined with state-of-the-art infrared luminescent nanothermometers (LNTh; Ag2S nanoparticles) in a nanocapsule that simultaneously overcomes these limitations. The novel optomagnetic nanocapsule acts as multimodal contrast agents for different imaging techniques (magnetic resonance, photoacoustic and near-infrared fluorescence imaging, optical and X-ray computed tomography). Most crucially, these nanocapsules provide accurate (0.2 °C resolution) and real-time subcutaneous thermal feedback during in vivo MHT, also enabling the attainment of thermal maps of the area of interest. These findings are a milestone on the road toward controlled magnetothermal therapies with minimal side effects ; E.X. and R.M. contributed equally to this work. Work partially supported by the Ministerio de Ciencia, Innovación y Universidades (PID2019-106301RB-I00 and PID2019-105195RA-I00), by the Spanish Ministry of Economy and Competitiveness (MAT2017-85617-R, SEV-2016-0686), by the Comunidad de Madrid (RENIM-CM, B2017/BMD-3867, co-financed by the European Structural and Investment Fund; NANOMAGCOST-CM P2018/NMT-4321), by the European COST Actions CA17115 (MyWave) and CA17140 (Nano2Clinic), by the Spanish Scientific Network HiperNano (RED2018-102626-T) and by the European Commission Horizon 2020 project NanoTBTech (Grant Number: 801305). D.G.-C. acknowledges CAM for funding PEJ-2018-AI/IND-11245. A.B. acknowledges funding from Comunidad de Madrid through TALENTO grant ref. 2019-T1/IND 14014. E.X. is grateful for a Juan de la Cierva Formación scholarship (FJC2018-036734-I). R.M. acknowledges the support of the European Commission through the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant agreement N 797945 (LANTERNS). A. E. acknowledges the support from Comunidad de Madrid (Talento project 2018-T1/IND-1005) and from AECC (Ideas Semilla 2019 project). P.R.S. is grateful for a Juan de la Cierva Incorporación scholarship (IJC2019-041915-I). Procedures involving animal experiments were approved by the regional authority for animal experimentation of the Comunidad de Madrid and were conducted in agreement with the Universidad Autónoma de Madrid Ethics Committee, in compliance with the European Union directives 63/2010UE and Spanish regulation RD 53/2013