Live bio-imaging with fully bio-compatible organic fluorophores

Area of Science:

• Organic chemistry
• Biophysics
• Cell biology

Background:

• Resveratrol glucoside is a naturally occurring phytoalexin found in plants like berries and grapes.
• Resveratrone, a precursor molecule, exhibits favorable optical properties and low cytotoxicity.
• There is a need for biocompatible, water-soluble organic fluorophores for advanced biological imaging.

Purpose of the Study:

• To synthesize and characterize a novel organic fluorescent dye, resveratrone glucoside.
• To evaluate the optical properties and biocompatibility of resveratrone glucoside.
• To demonstrate its utility in various fluorescence microscopy and live imaging applications.

Main Methods:

• Photoreaction of resveratrol glucoside to synthesize resveratrone glucoside.
• Assessment of optical properties: fluorescence quantum yield, Stokes' shift, and two-photon absorption cross section.
• Cytotoxicity evaluation using cell morphological studies, trypan blue exclusion assay, and Western blot analysis.
• Fluorescence microscopic imaging and live imaging of biological specimens (E. coli, yeast, mammalian cells, zebrafish embryos).

Main Results:

• Resveratrone glucoside was successfully synthesized from resveratrol glucoside.
• The new dye possesses excellent optical properties, including high fluorescence quantum yield and large Stokes' shift.
• Resveratrone glucoside demonstrated remarkably low cytotoxicity and superior aqueous solubility compared to its predecessor.
• Effective one- and two-photon fluorescence imaging was achieved in various cell lines and live zebrafish embryos.

Conclusions:

• Resveratrone glucoside is a highly promising, biocompatible organic fluorophore with excellent optical characteristics.
• Its enhanced water solubility makes it particularly suitable for in vivo imaging applications.
• The simple synthesis from readily available, inexpensive starting materials facilitates its accessibility for research.