From Live Cells to Caenorhabditis elegans: Selective Staining and Quantification of Lipid Structures Using a Fluorescent Hybrid Benzothiadiazole Derivative.

The current article describes the synthesis, characterization, and application of a designed hybrid fluorescent BTD-coumarin (2,1,3-benzothiadiazole-coumarin) derivative (named BTD-Lip). The use of BTD-Lip for live-cells staining showed excellent results, and lipid droplets (LDs) could be selectively stained. When compared with the commercially available dye (BODIPY) for LD staining, it was noted that the designed hybrid fluorescence was capable of staining a considerable larger number of LDs in both live and fixed cells (ca. 40% more). The new dye was also tested on live Caenorhabditis elegans (complex model) and showed an impressive selectivity inside the worm, whereas the commercial dye showed no selectivity in the complex model.

Preferential Mitochondrial Localization of a Goniothalamin Fluorescent Derivative.

A fluorescent 2,1,3-benzothiadiazole-containing goniothalamin derivative, BTD-GTN (1), has been synthesized and successfully tested in bioimaging experiments in live cells. The fluorescent compound proved to be capable of transposing the cell membranes, indicating its subcellular localization. The use of the benzothiadiazole core as the fluorophore revealed the favored localization of the GTN analogue 1 in the cytoplasm of live cells, preferentially in the mitochondria, in line with previous results that indicated the loss of mitochondrial transmembrane potential upon treatment with GTN. The results described herein highlight the potential of the BTD-GTN hybrid structures for future studies regarding the cellular mechanism of action of this family of compounds.