Suchergebnisse

The exciting advancements that we are currently witnessing in terms of novel materials and synthesis approaches are leading to the development of colloidal nanoparticles (NPs) with increasingly greater tunable properties. We have now reached a point where it is possible to synthesize colloidal NPs with functionalities tailored to specific societal demands. The impact of this new wave of colloidal NPs has been especially important in the field of biomedicine. In that vein, luminescent NPs with improved brightness and near-infrared working capabilities have turned out to be optimal optical probes that are capable of fast and high-resolution in vivo imaging. However, luminescent NPs have thus far only reached a limited portion of their potential. Although we believe that the best is yet to come, the future might not be as bright as some of us think (and have hoped!). In particular, translation of NP-based fluorescence imaging from preclinical studies to clinics is not straightforward. In this Perspective, we provide a critical assessment and highlight promising research avenues based on the latest advances in the fields of luminescent NPs and imaging technologies. The disillusioned outlook we proffer herein might sound pessimistic at first, but we consider it necessary to avoid pursuing "pipe dreams"and redirect the efforts toward achievable - yet ambitious - goals ; This work has been cofinanced by European Structural and Investment Fund and by the European Union's Horizon 2020 FET Open program under grant agreement no. 801305 (NanoTBTech). E.X. is grateful for a Juan de la Cierva Formacion scholarship (FJC2018-036734-I). A.B. acknowl- ́ edges funding from Comunidad de Madrid through TALENTO grant ref. 2019-T1/IND-14014. D.J

This is the peer reviewed version of the following article: Marin, R., Lifante, J., Besteiro, L. V., Wang, Z., Govorov, A. O., Rivero, F., . & Jaque, D. (2020). Plasmonic Copper Sulfide Nanoparticles Enable Dark Contrast in Optical Coherence Tomography. Advanced Healthcare Materials 2020 9.5 (2020): 1901627, which has been published in final form at https://onlinelibrary.wiley.com/doi/full/10.1002/adhm.201901627. This article may be used for non-commercial purposes in accordance with Wiley Terms and Conditions for Use of Self-Archived Versions ; Optical coherence tomography (OCT) is an imaging technique affording noninvasive optical biopsies. Like for other imaging techniques, the use of dedicated contrast agents helps better discerning biological features of interest during the clinical practice. Although bright OCT contrast agents have been developed, no dark counterpart has been proposed yet. Herein, plasmonic copper sulfide nanoparticles as the first OCT dark contrast agents working in the second optical transparency window are reported. These nanoparticles virtually possess no light scattering capabilities at the OCT working wavelength (≈1300 nm); thus, they exclusively absorb the probing light, which in turn results in dark contrast. The small size of the nanoparticles and the absence of apparent cytotoxicity support the amenability of this system to biomedical applications. Importantly, in the pursuit of systems apt to yield OCT dark contrast, a library of copper sulfide nanoparticles featuring plasmonic resonances spanning the three optical transparency windows is prepared, thus highlighting the versatility and potential of these systems in light-controlled biomedical applications ; This project was partially funded by the European Commission through the European Union's Horizon 2020 research and innovation program under the Marie Skłodowska-Curie Grant agreement No. 797945 "LANTERNS". This work was partially supported by the Ministerio de Economía y Competitividad de España (MAT2016-75362-C3-1-R) and (MAT2017-83111R), by the Instituto de Salud Carlos III (PI16/00812), by the Comunidad Autónoma de Madrid (B2017/BMD-3867RENIMCM), and co-financed by the European Structural and investment fund. Additional funding was provided by the European Commission Horizon 2020 project NanoTBTech. L.V.B was supported by the Institute of Fundamental and Frontier Sciences, University of Electronic Science and Technology of China and China Postdoctoral Science Foundation (2017M622992 and 2019T120820). Z.W. was supported by the National Basic Research Program of China (Project 2013CB933301) and the National Natural Science Foundation of China (Project 51272038). A.G. was funded via the 1000-talent Award of Sichuan and by the Volkswagen Foundation. Prof. Jorge Rubio-Retama is gratefully acknowledged for granting access to the dynamic light scattering instrument and for the fruitful discussion

Temperature of tissues and organs is one of the first parameters affected by physiological and pathological processes, such as metabolic activity, acute trauma, or infection-induced inflammation. Therefore, the onset and development of these processes can be detected by monitoring deviations from basal temperature. To accomplish this, minimally invasive, reliable, and accurate measurement of the absolute temperature of internal organs is required. Luminescence nanothermometry is the ideal technology for meeting these requirements. Although this technique has lately undergone remarkable developments, its reliability is being questioned due to spectral distortions caused by biological tissues. In this work, how the use of bright Ag2S nanoparticles featuring temperature-dependent fluorescence lifetime enables reliable and accurate measurement of the absolute temperature of the liver in mice subjected to lipopolysaccharide-induced inflammation is demonstrated. Beyond the remarkable thermal sensitivity (≈ 3% °C–1 around 37 °C) and thermal resolution obtained (smaller than 0.3 °C), the results included in this work set a blueprint for the development of new diagnostic procedures based on the use of intracorporeal temperature as a physiological indicator ; Y.S. J.L., and I.Z.-G. contributed equally to this work. This work was supported by the Spanish Ministerio de Ciencia under project PID2019-106211RB-I00 and Ministerio de Economía y Competitividad under project MAT2017-83111R, by the Comunidad Autónoma de Madrid (B2017/BMD-3867 RENIM-CM), and co-financed by the European Structural and Investment fund. Additional funding was provided by the European Union's Horizon 2020 FET Open program (Grant Agreement No. 801305, NanoTBTech), and also by COST action CA17140. Y.S. acknowledges a scholarship from the China Scholarship Council (No. 201806870023). I.Z.-G. thanks UCM-Santander for a predoctoral contract (CT63/19-CT64/19). M.F was funded by a research contract from the Community of Madrid (PEJ-2018-AI/SAL-11315). E.X. is grateful for a Juan de la Cierva Formación scholarship (FJC2018-036734-I). J.L. is grateful for FPI scholarship PID2019-106211RB-100. A. B. acknowledges funding from Comunidad de Madrid through TALENTO grant ref. 2019-T1/IND-14014

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