Sun Mingqi, Meng Jiaqi, Bao Weier, Liu Ming, Li Xiaojuan, Wang Zicheng, Ma Zhecheng, Wang Xuefei, Tian Zhiyuan
School of Chemical Sciences, University of Chinese Academy of Sciences (UCAS), Beijing, 100049, China.
Chemphyschem. 2023 Mar 14;24(6):e202200716. doi: 10.1002/cphc.202200716. Epub 2022 Dec 13.
Room temperature phosphorescence (RTP) materials are characterized with emission after removing the excitation source. Such long-lived emission feature possesses great potential in biological fluorescence imaging because it enables a way regarding temporal dimension for separating the interference of autofluorescence and common noises typically encountered in conventional fluorescence imaging. Herein, we constructed a new type of mesoporous silica nanoparticles (MSNs)-based composite nanoparticles (NPs) with dual-color long-lived emission, namely millisecond-level green phosphorescence and sub-millisecond-level delayed red fluorescence by encapsulating a typical RTP dye and Rhodamine dye in the cavities of the MSNs with the former acting as energy donor (D) while the latter as acceptor (A). Benefiting from the close D-A proximity, energy match between the donor and the acceptor and the optimized D/A ratio in the composite NPs, efficient triplet-to-singlet Förster resonance energy transfer (TS-FRET) in the NPs occurred upon exciting the donor, which enabled dual-color long-lived emission. The preliminary results of dual-color correlation imaging of live cells based on such emission feature unequivocally verified the unique ability of such NPs for distinguishing the false positive generated by common emitters with single-color emission feature.
室温磷光（RTP）材料的特征在于在去除激发源后仍有发射。这种长寿命发射特性在生物荧光成像中具有巨大潜力，因为它为在时间维度上分离传统荧光成像中常见的自发荧光和普通噪声的干扰提供了一种方法。在此，我们通过将一种典型的RTP染料和罗丹明染料封装在介孔二氧化硅纳米颗粒（MSNs）的孔穴中，构建了一种具有双色长寿命发射的新型基于MSNs的复合纳米颗粒（NPs），即毫秒级绿色磷光和亚毫秒级延迟红色荧光，其中前者作为能量供体（D），后者作为受体（A）。得益于复合纳米颗粒中供体-受体的紧密接近、供体与受体之间的能量匹配以及优化的D/A比，在激发供体时，纳米颗粒中发生了有效的三线态到单线态福斯特共振能量转移（TS-FRET），从而实现了双色长寿命发射。基于这种发射特性的活细胞双色相关成像的初步结果明确验证了此类纳米颗粒区分具有单色发射特性的普通发射体产生的假阳性的独特能力。
