RHOD 2 triammonium salt (CAS 129787-65-1)

RHOD 2 triammonium salt is a potent fluorescent dye used extensively in cell biology research to monitor and measure intracellular calcium (Ca²⁺) levels, crucial for understanding cellular signaling and function. Unlike some other calcium indicators, RHOD 2 is characterized by its red fluorescence, which allows researchers to use it in combination with other fluorophores like GFP (green fluorescent protein) without spectral overlap, facilitating multi-parameter imaging studies. The triammonium salt form of RHOD 2 enhances its water solubility, making it easier to load into cells. Once inside the cell, RHOD 2 is typically esterified to enable cell membrane permeability. Cellular esterases then cleave these ester groups, trapping the active dye within the cell where it can bind to calcium ions. This binding significantly enhances the dye′s fluorescence intensity, which is directly proportional to the concentration of calcium within the cell. This characteristic makes RHOD 2 invaluable for real-time studies of dynamic calcium signaling events such as muscle contraction, neuronal activity, and various cellular response mechanisms to physiological or pharmacological stimuli. The use of RHOD 2 in research has been pivotal for dissecting the intricacies of calcium-mediated intracellular processes, offering insights into the complex and vital roles of calcium as a key secondary messenger in cellular physiology.