Fluorescence ratiometry and fluorescence lifetime (FLIM) imaging: Dual mode imaging cellular viscosity by a single molecular rotor

Abstract

Intracellular viscosity strongly influences transportation of mass and signal, interactions between the biomacromolecules, and diffusion of reactive metabolites in live cells such as ROS and RNS. Intracellular viscosity changes relate to a number of diseases and pathologies. So it is meaningful to investigate the microviscosity at cellular level. Fluorescent molecular rotors are recently developed sensors used to determine the environmental viscosity. Due to the complexity of live cells, it is important to carry out the viscosity determinations in multimode for high reliability and accuracy. The first molecular rotor (RY) capable of dual mode fluorescence imaging (ratiometry imaging and fluorescence lifetime imaging) of intracellular viscosity is reported.[1]