Rhodamine 101 (inner salt)

Rhodamine 101 (inner salt) (CAS No.: 116450-56-7) is a xanthene-based fluorescent dye widely utilized as a high-performance probe in biomedical research, characterized by excitation and emission maxima at approximately 565 nm and 595 nm, respectively. As a synthetic fluorophore, it does not exert biological activity through specific molecular targets or signaling pathways but instead functions via its photophysical properties, enabling sensitive detection and visualization in complex biological systems. Its strong fluorescence intensity and photostability make it particularly suitable for applications such as fluorescence microscopy, flow cytometry, fluorescence correlation spectroscopy, and enzyme-linked immunosorbent assays, where it facilitates precise cell labeling, protein localization, and quantitative analysis. In vitro, its use is typically defined by concentration ranges optimized for signal intensity and minimal background interference rather than pharmacological potency, generally falling within low micromolar to nanomolar levels depending on assay conditions. Rhodamine 101 (inner salt) is commonly employed in cell-based imaging and analytical platforms in drug discovery workflows to enhance detection sensitivity and assay robustness, with experimental concentrations tailored to specific probe loading requirements and instrument configurations.