Fluorescent sterol probes for intracellular transport, imaging, and therapeutics.

Sterols play a significant role in many physiological processes affecting membrane organization, transport, permeability, and signal transduction. The development of fluorescent sterol analogs that have immediate functional relevance to the natural biomolecules is one approach to understanding the sterol-driven physiological processes. Visualizing cellular compartments with tailor-made fluorescent molecules through specific labeling methods enables organelle targeting and reveals dynamic information.

Stress-responsive rhodamine bioconjugates for membrane-potential-independent mitochondrial live-cell imaging and tracking.

The 'powerhouses' of cell, mitochondria have seen an upsurge of interest in investigations pertaining to the imaging and mapping of physiological processes. By utilizing sterol-modified rhodamine, we have performed the live-cell imaging of mitochondria without dependence on a membrane potential. The sterol probes are highly biocompatible, and they can track the mitochondrial live-cell dynamics in a background-free manner with improved brightness and impressive contrast.

Probing Variations of Reduction Activity at the Plasma Membrane Using a Targeted Ratiometric FRET Probe.

Plasma membrane (PM) is the turntable of various reactions that regulate essential functionalities of cells. Among these reactions, the thiol disulfide exchange (TDE) reaction plays an important role in cellular processes. We herein designed a selective probe, called membrane reduction probe (MRP), that is able to report TDE activity at the PM.

Live-cell imaging of the nucleolus and mapping mitochondrial viscosity with a dual function fluorescent probe.

Visualization of sub-cellular organelles allows the determination of various cellular processes and the underlying mechanisms. Herein, we report a fluorescent probe, bearing push-pull substituents emitting at 600 nm and its application in cellular imaging. The probe shows dual imaging of mitochondria and nucleoli and maps mitochondrial viscosity in live cells under various physiological variations and show minimum cytotoxicity.

Imaging mitochondria and plasma membrane in live cells using solvatochromic styrylpyridines.

Investigating the dynamics of different biomolecules in the cellular milieu through microscopic imaging has gained paramount importance in the last decade. Continuous developments in the field of microscopy are paralleled by the design and synthesis of fluorophores that target specific compartments within a cell. In this study, we have synthesized four fluorescent styrene derivatives, a neutral styrylpridine, three cationic styrylpyridinium probes with and without cholesterol tether, and investigated their absorption, emission, and cellular imaging properties.