Amphiphilic coumarin-based probes for live-cell STED nanoscopy of plasma membrane

• Published in: Bioorganic chemistry Vol. 150; pp. 107554 - 107563
• Main Authors: Kokot, Hana, Kokot, Boštjan, Pišlar, Anja, Esih, Hana, Gabrič, Alen, Urbančič, Dunja, El, Rojbin, Urbančič, Iztok, Pajk, Stane
• Format: Journal Article
• Language: English
• Published: SAN DIEGO Elsevier Inc 01.09.2024; Elsevier
• Subjects: Biochemistry & Molecular Biology; Cell Membrane - chemistry; Cell Survival - drug effects; Chemistry; Chemistry, Organic; Coumarins - chemistry; Coumarins - pharmacology; Fluorescence; Fluorescent Dyes - chemical synthesis; Fluorescent Dyes - chemistry; Humans; Life Sciences & Biomedicine; Membrane probe; Microscopy, Fluorescence; Molecular Structure; Photostability; Physical Sciences; Science & Technology; STED; Surface-Active Agents - chemistry; Surface-Active Agents - pharmacology; Two-photon excitation; Membrane probe; Fluorescence; Two-photon excitation; STED; Photostability; EMISSION; Two -photon excitation
• ISSN: 0045-2068; 1090-2120; 1090-2120
• DOI: 10.1016/j.bioorg.2024.107554

[Display omitted] •SHE-2N provides quick and stably stable labeling of plasma membrane.•No cytotoxicity detected for SHE-2N at concentrations used for imaging.•Suitable for STED nanoscopy and two-photon excitation microscopy.•SHE-2N offers high photostability.•Lipid composition does not affect emission or fluorescence lifetime of SHE-2N. Plasma membranes are vital biological structures, serving as protective barriers and participating in various cellular processes. In the field of super-resolution optical microscopy, stimulated emission depletion (STED) nanoscopy has emerged as a powerful method for investigating plasma membrane-related phenomena. However, many applications of STED microscopy are critically restricted by the limited availability of suitable fluorescent probes. This paper reports on the development of two amphiphilic membrane probes, SHE-2H and SHE-2N, specially designed for STED nanoscopy. SHE-2N, in particular, demonstrates quick and stable plasma membrane labelling with negligible intracellular redistribution. Both probes exhibit outstanding photostability and resolution improvement in STED nanoscopy, and are also suited for two-photon excitation microscopy. Furthermore, microscopy experiments and cytotoxicity tests revealed no noticeable cytotoxicity of probe SHE-2N at concentration used for fluorescence imaging. Spectral analysis and fluorescence lifetime measurements conducted on probe SHE-2N using giant unilamellar vesicles, revealed that emission spectra and fluorescence lifetimes exhibited minimal sensitivity to lipid composition variations. These novel probes significantly augment the arsenal of tools available for high-resolution plasma membrane research, enabling a more profound exploration of cellular processes and dynamics.