Rhod-3 Calcium Imaging Kit (Invitrogen™)

The novel Rhod-3 Calcium Imaging Kit is designed for live-cell imaging of cytosolic calcium signaling in combination with green-fluorescent dyes or proteins.The red-fluorescent Rhod-3 AM dye supplied in the Rhod-3 Calcium Imaging Kit offers significant improvements over existing Ca²⁺-sensing dyes. The uptake into organelles has been reduced, which translates into better cytosolic localization. Also, Rhod-3 AM exhibits a large increase in fluorescence emission upon binding to calcium, making it more sensitive than other red-fluorescent calcium dyes.

Learn more about ion indicators including calcium, potassium, pH, and membrane potential indicators ›

• Compared to existing red calcium dyes, Rhod-3 AM exhibits a large increase (>2.5 fold) in fluorescence upon binding Ca²⁺ and very low fluorescence at rest (without Ca²⁺ binding).

• Narrow emission enables simultaneous detection with GFP or other dyes.

• Enhanced cytosolic localization for better detection of cytosolic transients

For easy cell loading, the Rhod-3 Calcium Imaging Kit contains PowerLoad™ Concentrate. Due to the unique nature of the PowerLoad™ solution, it can be used in the presence of complete culture media, thus reducing the negative effects of replacing media or loading in serum-free media.

A proprietary, water-soluble form of probenecid (which is commonly used to inhibit cellular transport and thus reduces the baseline signal) is also supplied with the Rhod-3 Calcium Imaging Kit.

Calcium indicators are important tools in signal transduction and cell-based pharmacological screening. In cells and tissues with blue or green autofluorescence, long-wavelength (i.e., red-shifted) calcium indicators provide a means to bypass this overlapping autofluorescence. Additionally, red-shifted calcium dyes are well suited for calcium imaging experiments multiplexed with green-fluorescent protein (GFP) or other green fluorescent dyes.

The Rhod-3 AM dye (included in the Rhod-3 Calcium Imaging Kit) is an improved red-shifted rhodamine-based calcium dye with an attached AM ester group. Once inside the cell, intracellular esterases cleave the AM group, trapping the dye in the cell and rendering the dye fluorescent. As calcium binds, the fluorescence intensity of the dye is enhanced. The spectral properties of Rhod-3 AM (ex/em = ∼560/600 nm) and strong fluorescence upon calcium binding provide an excellent signal window and make it our brightest red calcium dye. Additionally, Rhod-3 AM displays a more uniform cytosolic distribution and improved signal compared to existing red calcium dyes such as Rhod-2.