Designing a green-emitting viscosity-sensitive 4,4-difluoro-4-bora-3a,4a-diaza-<i>s</i>-indacene (BODIPY) probe for plasma membrane viscosity imaging
Artūras Polita, Milda Stancikaitė, Rokas Žvirblis, Karolina Maleckaitė, Jelena Dodonova‐Vaitkūnienė, Sigitas Tumkevičius, Arun Prabha Shivabalan, Gintaras Valinčius
Abstract
suffers from poor integration into liquid-ordered lipid phases and lack of water solubility. Here, we investigate the photophysical characteristics of BODIPY-PM and demonstrate that solvent polarity only slightly affects the viscosity-sensing qualities of BODIPY-PM. In addition, with fluorescence lifetime imaging microscopy (FLIM), we imaged microviscosity in complex biological systems - large unilamellar vesicles (LUVs), tethered bilayer membranes (tBLMs) and live lung cancer cells. Our study showcases that BODIPY-PM preferentially stains the plasma membranes of live cells, equally well partitions into both liquid-ordered and liquid-disordered phases and reliably distinguishes lipid phase separation in tBLMs and LUVs.