Institut de Chimie Moléculaire, ICMUB CNRS UMR6302, University of Burgundy Franche-Comté, 9 avenue Alain Savary, 21078, Dijon, France.
Centre George-François Leclerc (CGFL), 1 rue du Professeur Marion, 21079, Dijon, France.
Sci Rep. 2017 Mar 24;7:45063. doi: 10.1038/srep45063.
Cherenkov Radiation (CR), this blue glow seen in nuclear reactors, is an optical light originating from energetic β-emitter radionuclides. CR emitter Y triggers a cascade of energy transfers in the presence of a mixed population of fluorophores (which each other match their respective absorption and emission maxima): Cherenkov Radiation Energy Transfer (CRET) first, followed by multiple Förster Resonance Energy transfers (FRET): CRET ratios were calculated to give a rough estimate of the transfer efficiency. While CR is blue-weighted (300-500 nm), such cascades of Energy Transfers allowed to get a) fluorescence emission up to 710 nm, which is beyond the main CR window and within the near-infrared (NIR) window where biological tissues are most transparent, b) to amplify this emission and boost the radiance on that window: EMT6-tumor bearing mice injected with both a radionuclide and a mixture of fluorophores having a good spectral overlap, were shown to have nearly a two-fold radiance boost (measured on a NIR window centered on the emission wavelength of the last fluorophore in the Energy Transfer cascade) compared to a tumor injected with the radionuclide only. Some CR embarked light source could be converted into a near-infrared radiation, where biological tissues are most transparent.
切伦科夫辐射（CR），这种在核反应堆中看到的蓝色辉光，是源自高能β发射放射性核素的光学光。CR 发射器 Y 在混合荧光团（彼此匹配其各自的吸收和发射最大值）存在的情况下引发能量转移级联：首先是切伦科夫辐射能量转移（CRET），然后是多个Förster 共振能量转移（FRET）：CRET 比被计算以粗略估计转移效率。虽然 CR 是蓝色加权的（300-500nm），但这种能量转移级联允许 a）荧光发射高达 710nm，这超出了主要的 CR 窗口，并且在近红外（NIR）窗口中，生物组织最透明，b）放大这种发射并增强该窗口上的辐射：已经证明，用放射性核素和具有良好光谱重叠的荧光团混合物注射 EMT6 肿瘤-bearing 小鼠，与仅用放射性核素注射的肿瘤相比，近红外窗口（以能量转移级联中最后一个荧光团的发射波长为中心）的辐射增强了近两倍。一些携带切伦科夫辐射的光源可以转化为近红外辐射，在该区域生物组织最透明。
