Nano-Science Center & Department of Chemistry, University of Copenhagen, Copenhagen, Denmark.
PLoS One. 2020 Mar 16;15(3):e0230441. doi: 10.1371/journal.pone.0230441. eCollection 2020.
Intrinsic fluorescence of biological material, also called auto-fluorescence, is a well-known phenomenon and has in recent years been used for imaging, diagnostics and cell viability studies. Here we show that in addition to commonly observed auto-fluorescence, intrinsic anti-Stokes emission can also be observed under 560 nm or 633 nm excitation. The anti-Stokes emission is shown to be spatially located on/in the mitochondria. The findings presented here show that sensitive imaging experiments e.g. single molecule experiments or two-photon excitation imaging can be compromised if intracellular anti-Stokes emission is not accounted for. On the other hand, we suggest that this anti-Stokes emission could be exploited as an additional modality for mitochondria visualization and cell viability investigation even in systems that are already labeled with commonly used fluorophores that rely on normal Stokes-based detection.
生物材料的固有荧光，也称为自发荧光，是一种众所周知的现象，近年来已被用于成像、诊断和细胞活力研究。在这里，我们表明，除了常见的自发荧光之外，在 560nm 或 633nm 激发下也可以观察到固有反斯托克斯发射。反斯托克斯发射被证明是位于线粒体内部或之上。这里提出的发现表明，如果不考虑细胞内反斯托克斯发射，敏感的成像实验（例如单分子实验或双光子激发成像）可能会受到影响。另一方面，我们建议，即使在已经用依赖于正常斯托克斯检测的常用荧光染料进行标记的系统中，这种反斯托克斯发射也可以被用作线粒体可视化和细胞活力研究的另一种方式。
