Fluorescence imaging is a major driver of discovery in biology, and an invaluable asset in clinical diagnostics. To overcome quenching limitations of conventional fluorescent dyes and further improve intensity, nanoparticle-based constructs have been the subject of intense investigation, and within this realm, dye-doped silica-coated nanoparticles have garnered significant attention. Despite their growing popularity in research, fluorescent silica nanoparticles suffer from a significant flaw. The degradation of these nanoparticles in biological media by hydrolytic dissolution is underreported, leading to serious misinterpretations, and limiting their applicability for live cell and in vivo imaging. Here, the development of an ultra-stable, dye-embedded, silica-coated metal nanoparticle is reported, and its superior performance in long-term live cell imaging is demonstrated. While conventional dye-doped silica nanoparticles begin to degrade within an hour in aqueous media, by leveraging a modified liquid calcination process, this new construct is shown to be stable for at least 24 h. The stability of this metal-enhanced fluorescent probe in biologically relevant temperatures and media, and its demonstrated utility for cell imaging, paves the way for its future adoption in biomedical research.

荧光成像是生物学发现的主要驱动力，也是临床诊断中的宝贵资产。为了克服传统荧光染料的淬灭限制并进一步提高强度，基于纳米粒子的结构一直是深入研究的主题，在这个领域内，染料掺杂的二氧化硅涂层纳米粒子已经引起了极大的关注。尽管它们在研究中越来越受欢迎，但荧光二氧化硅纳米粒子仍存在重大缺陷。这些纳米颗粒在生物介质中通过水解溶解降解的报道不足，导致严重的误解，并限制了它们在活细胞和体内成像中的适用性。在这里，报道了一种超稳定、染料嵌入、二氧化硅包覆的金属纳米颗粒的开发，并证明了其在长期活细胞成像中的卓越性能。虽然传统的掺杂染料的二氧化硅纳米粒子在水性介质中在一小时内开始降解，但通过利用改进的液体煅烧工艺，这种新结构显示出至少 24 小时是稳定的。这种金属增强型荧光探针在生物相关温度和介质中的稳定性及其在细胞成像中的实用性，为其未来在生物医学研究中的应用铺平了道路。