Rhodamine 6G

Technical Specifications

Product Description & Scientific Applications

Rhodamine 6G (R6G; Basic Red 1) is a cationic xanthene dye used as a high-brightness fluorophore, classical dye-laser gain medium, and reference/test probe in fluorescence photophysics, SERS, bioanalytical, and materials research. In ethanol it shows a visible absorption maximum near 530 nm, emission near 552 nm, ε ≈ 116 000 M⁻¹cm⁻¹, and a fluorescence quantum yield close to 0.95 — making it an important quantum-yield reference standard, alongside fluorescein and quinine sulfate. It is also highly photostable.

Tunable dye lasers and quantitative photophysics. R6G is a classical gain medium for tunable liquid dye lasers in the yellow-orange. The emission window is system-dependent (solvent, dye salt, concentration, pump, cavity), typically centred 560–610 nm with peaks near 575–590 nm. It combines strong pump absorption matching common sources (frequency-doubled Nd:YAG 532 nm, copper-vapour 511 nm, argon-ion 514 nm), high fluorescence efficiency, broad emission bandwidth, and good photostability — supporting high-resolution atomic and molecular spectroscopy, laser-induced fluorescence, beam diagnostics, and work needing continuous wavelength tunability. It is also a standard in fluorescence-correlation-spectroscopy calibration and diffusion-coefficient method development.

Mitochondrial membrane potential and ABC-transporter research. As a lipophilic cation, R6G accumulates in mitochondria in a membrane-potential-dependent manner, supporting ΔΨm-linked bioenergetics readouts; rhodamine 123, TMRM, and TMRE are the more standard ΔΨm probes, with TMRM and TMRE showing lower potential-independent binding than R6G, and as with all cationic potential-sensitive dyes, accumulation, quenching, efflux, concentration, and cell-type effects demand calibration and controls. It is also a fluorescent substrate for ATP-binding-cassette transporters including P-glycoprotein/ABCB1 and MRP1, supporting flow-cytometric, imaging, and kinetic characterisation of dye accumulation and efflux; MRP1-mediated transport is glutathione-dependent in living cells, useful in mechanistic transporter and substrate-modulator studies.

SERS, TERS, and plasmonic substrate characterisation. R6G is the benchmark SERS analyte: strong visible absorption compatible with resonant or near-resonant 514/532 nm excitation, while 633 nm is also widely used in R6G SERS; high resonance-Raman/SERRS response; and a well-characterised vibrational fingerprint of multiple distinct intense peaks. It is routinely used to evaluate silver and gold colloids; electrodeposited, printed/flexible, nanoimprinted, or lithographically patterned substrates; plasmonic metasurfaces; and TERS systems, comparing enhancement factors, hot-spot behaviour, reproducibility, and detection limits. Foundational single-molecule SERS and modern ultrasensitive demonstrations use R6G as test analyte; reported enhancements and detection limits — including sub-femtomolar (~10⁻¹⁶ M) on optimised silver colloids — are strongly substrate-dependent, not intrinsic to the dye.

Tracer, photocatalysis, and materials research. Its intense fluorescence makes R6G a convenient visible-light tracer in microfluidics, environmental hydraulics, flow visualisation, mixing, and droplet analysis, and a latent-fingerprint visualisation reagent in forensic surface-treatment workflows. It is also a model cationic dye in adsorption, photocatalytic-degradation, and dye-removal studies on TiO₂, ZnO and other metal oxides, activated carbons, clays, MOF-based materials, and engineered nanomaterials, giving convenient absorbance or fluorescence readouts for degradation kinetics, adsorption capacity, surface interaction, and catalyst-performance comparison.

Shipping Destinations

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