Department of Chemistry, Pohang University of Science and Technology, Pohang 37673, Republic of Korea.
Center for Self-assembly and Complexity, Institute for Basic Science (IBS), Pohang 37673, Republic of Korea.
ACS Sens. 2020 Mar 27;5(3):731-739. doi: 10.1021/acssensors.9b01951. Epub 2020 Feb 27.
Viscosity in the intracellular microenvironment shows a significant difference in various organelles and is closely related to cellular processes. Such microviscosity in live cells is often mapped and quantified with fluorescent molecular rotors. To enable the rational design of viscosity-sensitive molecular rotors, it is critical to understand their working mechanisms. Herein, we systematically synthesized and investigated two sets of BODIPY-based molecular rotors to study the relationship between intramolecular motions and viscosity sensitivity. Through experimental and computational studies, two conformations (i.e., the planar and butterfly conformations) are found to commonly exist in BODIPY rotors. We demonstrate that the transformation energy barrier from the planar conformation to the butterfly conformation is strongly affected by the molecular structures of BODIPY rotors and plays a critical role in viscosity sensitivity. These findings enable rational structure modifications of BODIPY molecular rotors for highly effective protein detection and recognition.
细胞内微环境的粘度在各种细胞器中存在显著差异，与细胞过程密切相关。这种活细胞中的微观粘度通常使用荧光分子转子进行映射和量化。为了实现对粘度敏感的分子转子的合理设计，理解它们的工作机制至关重要。在此，我们系统地合成并研究了两组基于 BODIPY 的分子转子，以研究分子内运动与粘度敏感性之间的关系。通过实验和计算研究，发现 BODIPY 转子中通常存在两种构象（即平面构象和蝴蝶构象）。我们证明，从平面构象到蝴蝶构象的转变能垒强烈受到 BODIPY 转子分子结构的影响，并在粘度敏感性中起着关键作用。这些发现为 BODIPY 分子转子的合理结构修饰提供了依据，以实现对蛋白质的高效检测和识别。
