Abstract：
Optical bioimaging is an ever-growing field that benefits both from the fast progress of optical instrumentation and modalities, and from the development of light-emitting probes. The efficacy of molecular fluorescent dyes is crucial, yet hindered by limited brightness and hydrophilicity. Addressing these challenges, self-stabilized fluorogenic organic nanoparticles only made of pure dyes (dFONs) are introduced in this work. Comprising thiol-sensitive fluorogenic chromophores, these dFONs exhibit enhanced brightness exclusively in the presence of biological thiols, notably glutathione, overcoming the need for water-solubilizing moieties. Importantly, these nanoparticles demonstrate large fluorescence and one- and two-photon brightness, enabling sensitive bioimaging of intracellular thiols at micromolar concentrations. Notably, only the pristine fluorogenic nanoparticles can penetrate the cells and does not require to wash the cells before imaging, emphasizing their unique role as dye carriers, fluorogenic probes and ease of use. This work highlights the transformative potential of dFONs in advancing optical bioimaging, paving the way for the use of dFONs not just as tracers, but also now as biosensors and ultimately in the future as biomarkers.
摘要：
光学生物成像是一个不断发展的领域，受益于光学仪器和模态的快速发展，以及发光探针的发展。分子荧光染料的功效至关重要,但受到有限的亮度和亲水性的阻碍。应对这些挑战，在这项工作中引入了仅由纯染料（dFONs）制成的自稳定的荧光有机纳米颗粒。包括巯基敏感的荧光发色团，这些DFON仅在生物硫醇的存在下表现出增强的亮度，尤其是谷胱甘肽,克服了对水溶性部分的需要。重要的是,这些纳米粒子表现出大的荧光和单光子和双光子亮度，能够在微摩尔浓度下对细胞内硫醇进行灵敏的生物成像。值得注意的是,只有原始荧光纳米粒子才能穿透细胞，不需要在成像前清洗细胞，强调它们作为染料载体的独特作用，荧光探针和易用性。这项工作突出了dFONs在推进光学生物成像方面的变革潜力，为DFON的使用铺平了道路，而不仅仅是作为示踪剂，但现在也作为生物传感器，并最终在未来作为生物标志物。
