- Staining of viable and dead cells
- Detection of cellular structures
- Suited for e.g. fluorescence microscopy/flow cytometry
- High quality
- Thoroughly tested
- Highly sensitive
Lipophilic Carbocyanine Dyes
Carbocyanine dyes with long hydrocarbon chains were initially used for imaging neuronal cells in tissue preparations via retrograde labeling. Now they are widely used to label both neurons in tissues and cells in suspensions. Carbocyanine dyes have some of the highest absorbativity among fluorescent dyes and are highly fluorescent in lipid bilayers, while they are essentially non-fluorescent or only weakly fluorescent in aqueous phase. These spectral properties and the long lipophilic chains make this class of dyes ideal for staining the cytoplasmic membranes of the cells. The membrane staining is highly stable with very little dye transfer in between cells. The orange-red fluorescent DiI and its longer wavelength derivatives DiD and DiR belong to the sub-class of indocarbocyanine dyes and are far more widely used than the green fluorescent DiO, which belongs to the sub-class of oxacarbocyanine dyes. The primary reason for this is that DiO tends to be much less soluble than DiI and its derivatives. This problem has been solved by developing a new DiO derivative that is called Neuro-DiO. Neuro-DiO is an excellent green fluorescent membrane dye that can be optimally excited by the 488 Ar laser line and is more photostable than DiO. Finally, PromoKine also offers dilinoleyl carbocyanine dyes, in which two unsaturated hydrocarbon chains are attached to the nitrogens of the dyes. Dilinoleyl carbocyanines have much faster lateral diffusion rate than regular carbocyanine dyes with saturated C18 chains and thus are excellent for labeling neurons in tissues.
To facilitate the labeling of cells in suspension, a series of ready-to-use Cytoplasmic Membrane Labeling Kits with fluorescent colors from green to the infrared region are available. The labeling kits offer fast and intensely bright labeling of cells without dye precipitation.